Environment, 8th Edition Solution Manual

Environment, 8th Edition By Raven, Hassenzahl, Berg

Chapter 1 Introducing Environmental Science and Sustainability Lecture Outline: I. Human Impacts on the Environment A. Increasing human numbers i. Although several million species inhabit Earth, the human species is the most significant agent of environmental change on the planet ii. Over 6 billion people currently inhabit planet Earth iii. Human activities, such as overpopulation, deforestation, pollution and species eradication are disrupting global systems B. The gap between rich and poor countries i. 81% of the world’s population live in poor countries 1. Poor countries fall into two subcategories: moderately developed countries (Mexico, South Africa, Thailand) and less developed countries (LDCs - Bangladesh, Ethiopia, Laos) 2. Nearly one in four people lives in extreme poverty which is associated with low life expectancy, illiteracy, and inadequate access to health services, safe water, and balanced nutrition ii. Countries with complex industrialized bases, low rates of population growth, and high per capita incomes are considered highly developed countries (HDCs - Canada, Japan, the United States, and most of Europe) II. Population, Resources, and the Environment A. Types of resources i. Nonrenewable resources are present in limited supplies and are depleted by use (aluminum, tin, copper, fossil fuels) ii. Renewable resources are replaced by nature fairly rapidly and can be used forever as long as they are not overexploited in the short term (trees, animals, soils, fresh water) B. Resource consumption i. Consumption is the human use of materials ii. A single child born in a HDC causes a greater impact on the environment and on resource depletion than 12 or more children born in a developing country C. People overpopulation and consumption overpopulation i. A country is overpopulated if the level of demand on its resource base results in damage to the environment ii. A country can be overpopulated in two ways: people overpopulation (LDCs) and consumption overpopulation (HDCs) iii. The amount of productive land, fresh water, and ocean required on a continuous basis to supply a person food, wood, energy, water, housing, clothing, transportation, and waste disposal is termed an ecological footprint D. The IPAT model i. The IPAT model shows the mathematical relationship between environmental impacts and the forces driving them: I = P x A x T

Chapter 1 ii. The three most important factors in determining environmental impact (I) are: number of people (P), the affluence per person (A), and the environmental effects of the technologies used to obtain and consume resources (T) III. Environmental Sustainability A. When the environment is used sustainably, humanity’s present needs are met without endangering the welfare of future generations B. Inadequate understanding of how the environment works and how human choices affect the environment is a major reason that problems of environmental sustainability are difficult to resolve C. Sustainability and the Tragedy of the Commons i. Proposed by Garrett Hardin in 1968, he postulates that our inability to solve many environmental problems is the result of a struggle between short-term individual welfare and long-term environmental sustainability and societal welfare ii. Effective legal and economic policies are needed to prevent the short-term degradation of our global commons iii. The shared responsibility for the sustainable care of our planet is termed stewardship D. Global plans for sustainable development i. The goals of Agenda 21 are achieving improved living conditions for all people while maintaining a healthy environment in which natural resources are not overused and excessive pollution is not generated iii. Three factors interact to promote sustainable development: environmentally sound decisions, economically viable decisions, and socially equitable decisions IV. Environmental Science A. Environmental science encompasses the many interconnected issues involving human population, Earth’s natural resources, and environmental pollution B. Earth systems and environmental science i. Understanding how systems that consist of many interacting parts function as a whole help scientists gain valuable insights that are not obvious when looking at system components ii. Environmental scientists often use models to describe the interaction within and among environmental systems iii. Many aspects of Earth’s systems are in a steady state of dynamic equilibrium 1. Feedback occurs when a change in one part of the system leads to a change in another part 2. A negative feedback mechanism works to keep an undisturbed system in dynamic equilibrium, and occurs when a change in some condition triggers a response that counteracts, or reverses, the changed condition 3. A positive feedback mechanism leads to greater change from the original condition, and occurs when a change in some condition triggers a response that intensifies the changing condition C. Science as a process i. There is no absolute certainty or universal agreement about anything in science; it is self-correcting over time

Chapter 1 ii. The established processes scientists use to answer questions or solve problems are collectively called the scientific method 1. The scientific method involves five steps: recognize a problem or unanswered question, develop a hypothesis, design and perform an experiment to test the hypothesis, analyze and interpret the data to reach a conclusion, share new knowledge 2. Scientists collect objective data by observation and experimentation a. Inductive reasoning is the basis of modern experimental science b. Deductive reasoning is used to determine the type of experiment or observations necessary to test a hypothesis 3. Controls and variables are accounted for in experimental design 4. Scientific theories are integrated explanations of numerous hypotheses, each supported by a large body of observations and experiments and evaluated by the peer review process V. Addressing Environmental Problems A. There are five stages in addressing an environmental problem: scientific assessment, risk analysis, public education and involvement, political action, evaluation B. The reversal of the pollution of Lake Washington is a clear example of how environmental science identifies and addresses environmental problems (read and discuss CASE IN POINT: Lake Washington)

Chapter 1

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Student Resource Use and IPAT

Time: Materials:

10 minutes prep; 15 – 20 OR 40 – 50 minutes in class Paper for class, or print instructions on worksheets. Post the instructions on a PowerPoint or overhead as an alternative to printing out instructions.

Either provide paper for students or let them bring their own.

Optional. See below.

Handouts: Procedures:

Divide class into at least five groups of two to four students. Assign each group of students to one of the five categories. Each group of students will try to estimate how much of one of five categories of resources a typical student uses in a single day. The categories are: 1. Agricultural 2. Consumer goods 3. Infrastructure 4. Water 5. Energy Notes to instructor: 1. Give the students the next following “challenge” after they have spent some time working on their lists 2. Keep in mind that there should be overlap in these lists. For example, energy is needed to provide any of the other four categories; agriculture is the source of multiple types of resources, and so on.

3. Use this lesson to emphasize that everything is either matter or energy 4. To shorten the exercise, omit the IPAT part, or assign as homework Next, have them evaluate the “technology” component of each, in the context of IPAT. Do this by having them assume that world Population will stabilize at about twice the current size, and all of those people will seek Affluence like that found in highly developed countries. What types of technologies would be required to keep Impacts constant? Is that even possible?

Student Instructions:

1. Estimate how much of the resource type assigned to you (Agricultural, consumer goods, infrastructure, water and energy) a typical student uses in a day. Think broadly!

2. Next, evaluate the “technology” component of your resource, in the IPAT model. Assume that world Population will stabilize at about twice the current size, and all of those people will seek Affluence like that found in highly developed countries. What

Chapter 1 types of Technologies would be required to keep Impacts constant? Is that even possible?

Specific Suggestions:

If more than 16 students are in your class, have more than one group work on each category. You may be able to skip the “thinking broadly”

Objectives:

• • •

Describe the resource use by students in highly developed countries Contrast this with resource use by people in less developed countries.

Describe the three most important factors that determine human impact on the environment.

Chapter 1 In-Class Activity 1: Handout 1. Estimate how much of the resource type assigned to you (Agricultural, consumer goods, infrastructure, water and energy) a typical student uses in a day. Think broadly!

2. Next, evaluate the “technology” component of your resource, in the IPAT model.

Assume that world Population will stabilize at about twice the current size, and all of those people will seek Affluence like that found in highly developed countries. What types of Technologies would be required to keep Impacts constant? Is that even possible?

Chapter 1

Instructor Notes for In-Class Activity 2 Title:

Do Americans Use Too Much?

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR (Americans Use Too Much) group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST (American Resource Use is Reasonable) group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

Student See above Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

Chapter 1 3. Be sure students argue their points forcefully, whether or not they believe them personally.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Describe the resource use by students in highly developed countries.

Chapter 1

Instructor Notes for In-Class Activity 3 Title:

Exploring Sustainability Efforts on Campus

Time: Materials: Handouts:

10 – 30 Minutes prep; full class period (assuming 50 – 75 minute period) None None

Procedures:

Divide students into groups of 3 – 6. Have each assess the extent to which your campus (or other relevant location) engages in sustainability efforts.

Student A campus cannot be a closed system. It requires inputs such as energy, Instructions: food, and water. It must export its wastes, including garbage and sewage.

Many campuses, whether for ethical, legal, financial, or other reasons, have sustainability efforts. These can range from the disjointed efforts of a few individuals and groups to centrally coordinated sustainability institutes. Use the internet to research and/or tour your campus with an eye to sustainability efforts.

Answer the following questions: 1. What types of efforts did you find?

2. Who is running them, and why?

3. Are they coordinated?

4. How effective do you think they are, and why?

5. Are there any simple, low cost things your campus could do to decrease its footprint? Why aren’t these things being done?

Specific Suggestions:

Instructor: you should be sure to do some prior investigation into what is being done. Note that if you are teaching a course for majors, this could be a useful thesis (or even several theses).

Objectives:

Define environmental sustainability.

Chapter 1

Instructor Notes for In-Class Activity 4 Title:

Final Good bye to Natural Resources

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

Have the students either individually or in small groups write an obituary on our natural resources. You could assign one natural resource for each group or have them write on “Natural Resources” in general and see what they come up with in their own selection for all.

Student Write out a 1-page obituary for the Natural Resources.

Instructions: Specific Suggestions: Objectives:

Discuss the importance of Natural Resources and what we would be like without them.

Chapter 1

Instructor Notes for In-Class Activity 5 Title:

Exclusive Environmental Problems

Time: Materials: Handouts:

10 minutes explanation time with 1 week prep time for the students None

Procedures:

Divide the students into groups and have them come up with an environmental problem that is exclusive to the area they live in. This could be different in the same class as some students live near railroads, some live near highways, new housing construction, old buildings etc. It would be good if the students lived close to their partners so they would have basically the same problem.

Student Working in groups of 3 or 4 have the students present to the rest of the Instructions: class their exclusive problem using the Figure 1.14 steps for the framework on addressing environmental problems.

Specific Suggestions: Objectives:

• • • .

Identify and Describe an environmental problem or condition that is exclusive to the living environment of the students.

Discuss the ways the problem can be solved or changed to make the area better environmentally.

Present ideas and solutions to the class in a systemic and scientific approach.

Chapter 1

Answers to Critical Thinking and Review End of Chapter Questions: 1. Why does a single child born in the United States have a greater effect on the environment than 12 or more children born in a developing country?

Ans: A single child born in a highly developed country such as the United States causes a greater impact on the environment and on resource depletion than do 12 or more children born in a developing country. Many natural resources are used to provide the automobiles, air conditioners, disposable diapers, cell phones, DVD players, computers, clothes, newspapers, athletic shoes, furniture, boats, and other “comforts” of life in highly developed nations.

Consumer goods, such as these, require vast materials and energy for production and distribution. Thus, the disproportionately large consumption of resources by the United States affects natural resources and the environment as much as or more than the population explosion in the developing world.

2. Do you think it is possible for the world to sustain its present population of more than 6.9 billion indefinitely? Why or why not?

Ans: The current global ecological footprint of each person is about 2.7 hectares (6.7 acres), which means humans have overshot our allotment. We can see the short-term results around us—forest destruction, degradation of croplands, loss of biological diversity, declining ocean fisheries, and local water shortages. The long-term outlook, if we do not seriously address our consumption of natural resources, is potentially disastrous. Therefore, it is not likely that we can maintain 6 billion people indefinitely.

3. Is consumption driven more by population than affluence in highly developed countries? Less developed countries? Explain the difference.

Ans: Consumption is the human use of materials and energy. In general the use of resources by consumers in highly developed countries is greatly out of proportion to their numbers. A single child born in a highly developed country may have a greater impact on the environment than 12 children born in developing countries. Many natural resources are required to provide automobiles, air conditioners, disposable diapers, cell phones, DVDs, computers, clothing, etc. in highly developed countries.

4. In this chapter we said the current global ecological footprint is 2.7 hectares (6.7 acres) per person. Do you think it will be higher, lower, or the same in 15 years? Explain your answer.

Ans: Answers will vary 5. How are the concepts of ecological footprint and the IPAT model similar? Which concept do you think is easier for people to grasp?

Ans: An ecological footprint is an average amount of productive land, fresh water, and ocean required on a continuous basis to supply a person food, wood, energy, water, housing, clothing,

Chapter 1 transportation, and waste disposal. The IPAT model, shows the mathematical relationship between environmental impacts and the forces driving them.

6. Explain the following ancient proverb as it relates to the concept of environmental sustainability: We have not inherited the world from our ancestors; we have borrowed it from our children.

Ans: Environmental sustainability is the ability to meet the current human need for natural resources without compromising the ability of future generations to meet their needs.

Sustainability implies that humans can manage natural resources indefinitely without the environment going into a decline from the stresses imposed by human society on natural systems that maintain life. When the environment is used sustainably, humanity's present needs are met without endangering the welfare of future generations.

7. Name an additional example of a common-pool resource other than those mentioned in this chapter.

Ans: Answers will vary 8. Explain why economic well-being, environment, and ethics all contribute to sustainable development.

Ans: Sustainability implies that humans can have economic development and fair allocation of resources without the environment going into decline. When the environment is used sustainably, humanity’s present needs are met without endangering the welfare of future generations. The goal of sustainable development is to ensure future economic development while protecting the environment. To ensure sustainability environmentally sound decisions, economically viable decisions, and socially equitable decisions must be thought of as a part of a complex and interlinked system.

9. Give an example of an Earth system?

Ans: At a global level are Earth systems, which include Earth’s climate, atmosphere, land, coastal zones, and the ocean. Environmental scientists use a systems approach to try to understand how human activities are altering global environmental parameters such as temperature, carbon dioxide concentration in the atmosphere, land cover, changes in nitrogen levels in coastal waters, and declining fisheries in the ocean.

10. Thomas Henry Huxley once wrote, “The great tragedy of science—the slaying of a beautiful hypothesis by an ugly fact.” Explain what he meant, based on what you have learned about the nature of science.

Ans: A hypothesis is an educated guess, an explanation of a problem. A good hypothesis will make predictions about how the natural world works. These predictions can then be tested and possibly disproved. Sometimes a seemingly sound hypothesis is disproved by experimental data.

Chapter 1 Some people have strong beliefs about how the world should work but the scientific facts don’t always support those beliefs.

11. In the chapter, the term model is defined as a formal statement that describes a situation and can be used to predict the future course of events. On the basis of this definition, is a model the same thing as a hypothesis? Explain your answer.

Ans: A model is not the some thing as a hypothesis. A hypothesis is an educated guess that tries to explain the natural world. It breaks down complex systems into testable processes in order to explain the bigger picture. Many of models are computer simulations that represent the overall effect of competing factors to describe an environmental situation in numerical terms. Models help us understand how a present situation developed from the past or how to predict the future course of events.

12. Some people want scientists to give them precise, definitive answers to environmental problems. Explain why this is not possible.

Ans: Science is a dynamic process, a systematic way to investigate the natural world. Science seeks to reduce the apparent complexity of our world to general scientific laws. Scientific laws are then used to make predictions, solve problems, or provide new insights. There is no absolute certainty or universal agreement about anything in science. Science is an ongoing enterprise, and generally accepted ideas must be reevaluated in light of newly discovered data. Scientists never claim to know the “final answer” about anything because scientific understanding changes.

However, this must not prevent us from using current knowledge in environmental science to make environmental decisions.

13. Explain why it might be difficult to make a decision about whether or not to allow farmers to spray pesticides even if we all agree about negative health effects of the pesticides.

Ans: Answers will vary but should include economic impact on farmer and local community, importance of crop being grown, viability and availability of alternative crops that could be grown, availability and effectiveness of alternative pesticides or use of natural predators.

14. Place the following stages in addressing environmental problems in order and briefly explain each: long-term evaluation, public education and involvement, risk analysis, scientific assessment, political action.

Ans: 1. Scientific assessment involves identifying a potential environmental problem and collecting data to construct a model.

2. Risk analysis evaluates the potential effects of intervention.

3. Public education and involvement occur when the results of scientific assessment and risk analysis are placed in the public arena.

4. Political action is the implementation of a particular risk-management strategy by elected or appointed officials.

5. Long-term evaluation monitors the effects of the action taken.

Chapter 1 15. What does the term system mean in environmental science?

Ans: A system is set of components that interact and function as a whole. A natural system, consisting of a community of organisms and its physical environment, is known as an ecosystem.

Ecosystems are organized into larger systems that interact with one another. Natural ecosystems are the foundation for our concept of environmental sustainability.

16. In what ways do decisions about energy use and climate change that we make today limit the possibilities available to the next generation? Explain your answer.

Ans: In order to live in a sustainable way, we must make smart choices about energy use. If we use energy in excess, the environment will be degraded for future generations. In order to not affect future generations, humans must manage natural resources without the environment going into a decline from the stresses imposed by society.

17. Examine the graph, which shows and estimate of the discrepancy between the wealth of the world’s poorest countries and that of the richest countries.

a. How has the distribution of wealth changed from the 1880’s to the present? What explains this difference? b. Based on the trend evident in the graph, predict what the graph might look like in 100 years. c. Some economists think that our current path of economic growth is unsustainable. Are the data consistent with this idea? Explain your answer.

Ans: a) Wealth has increase significantly in developed countries and remained essential unchanged in developing countries. The majority of the manufacturing and industrial infrastructure is concentrated in developed countries. Developing countries normally provide the raw materials and not the final product. b) Significant increases in wealth in developed countries and essentially no net increase in developing countries. The gap between developed and developing countries will increase substantially. c) Yes – currently highly developed countries represent less than 20% of the world’s population, yet they consume significantly more than half of the earth’s resources. If long-term consumption of natural resources is not decreased the outlook could be disastrous.

Answers to Review Questions

Chapter 1 Human Impacts on the Environment 1. What is poverty?

Poverty is the condition in which people cannot meet their basic needs for adequate food, clothing, shelter, education, or health. Having a per capita income of less than $2 (U.S.) a day is one measure of poverty. It is estimated that more than 2.5 billion people currently live at this level of poverty; nearly 40% of the total world population.

2. What is a highly developed country? A moderately developed country? A less developed country?

Highly developed countries have complex industrialized bases, low rates of population growth, and high per capita incomes. Highly developed countries (i.e., the United States, Canada, and Japan) represent approximately 19% of the world’s population. Moderately developed countries are developing countries with a medium level of industrialization and average per capita incomes lower than those of highly developed countries.

Examples of moderately developed countries include Mexico, Turkey, South Africa, and Thailand. Less developed countries are developing countries with high poverty rates, low levels of industrialization, high fertility rates, high infant mortality rates, and very low per capita incomes (relative to highly developed countries). Less developed countries include Bangladesh, Mali, Ethiopia, and Laos.

Population, Resources, and the Environment 1. How are human population growth and affluence related to natural resource depletion?

As population increases, the sheer number of people can exceed the capacity of a region to support basic needs for food, shelter, and clean water. Additionally, when greater affluence is exhibited by individuals in a given population, the resources in that region will be exceeded even more quickly. In either case, consumption that exhausts both nonrenewable and renewable resources is unsustainable.

2. What is an ecological footprint?

The concept of an ecological footprint was developed by environmental scientists Mathis Wackernagel and William Rees. It is defined as the amount of productive land, fresh water, and ocean required on a continuous basis to supply an individual with food, energy, water, housing, material goods, transportation, and waste disposal.

3. What does the IPAT model demonstrate?

The IPAT model was first proposed by biologist Paul Ehrlich and physicist John Holdren.

It demonstrates the mathematical relationship between environmental impacts and the forces driving them (i.e., number of people, affluence per person, and the environmental

Chapter 1 effect of the technologies used to obtain and consume those resources). It is a valuable model because it helps identify what we do not know or understand about consumption and its environmental impact.

Sustainability 1. What is sustainability?

Sustainability is the ability to meet current human economic and social needs without compromising the ability of the environment to support future generations. The concept of environmental sustainability applies at many levels (i.e., from individual to global levels) and requires a long-term perspective to protect human welfare and natural resource assets. Efforts focused towards sustainability include stabilization of the human population, protection of natural ecosystems, education, pollution prevention, restoration of degraded environments, waste prevention and reduction, eradication of hunger and poverty, and efficient use of resources.

2. What is the tragedy of the commons?

“The Tragedy of the Commons” was an essay published in the journal Science by Garrett Hardin. In it he contended that our inability to solve many environmental problems is the result of a struggle between short-term individual welfare and long-term environmental sustainability and societal welfare.

3. What are the three foundations of sustainable development?

The three foundations of sustainable development are environmentally sound decisions, economically viable decisions, and socially equitable decisions.

Environmental Science 1. What is environmental science? Why is a systems perspective so important in environmental science?

Environmental science is the interdisciplinary study of humanity’s relationship with other organisms and the nonliving physical environment. It encompasses many interconnected issues (i.e., human population, environmental pollution, etc.), and combines information from many disciplines (i.e., biology, geology, chemistry, economics, etc.). Therefore, due its large scope, it is important that a systems perspective is used to analyze hypotheses in environmental science. A systems perspective provides a broad look at overall processes, as opposed to the details of individual parts or steps.

2. What are the steps of the scientific method? Does the scientific process usually follow these steps? Why or why not?

Chapter 1 The established processes scientists use to answer questions or solve problems are collectively called the scientific method. It basically involves five steps: (1) recognize a question or unexplained occurrence in the natural world; (2) develop a hypothesis to explain the problem; (3) design and perform an experiment to test the hypothesis; (4) analyze and interpret the data to reach a conclusion; (5) share the knowledge. The scientific process does not always follow these steps as science is rarely as straightforward or tidy as the scientific method implies.

Addressing Environmental Problems 1. What are the steps used to solve an environmental problem?

In general, there are five steps used in addressing environmental problems: (1) scientific assessment; (2) risk analysis; (3) public education and involvement; (4) political action; and (5) long-term evaluation.

2. What was the Lake Washington pollution problem of the 1950s? How was it addressed?

Lake Washington exemplifies a successful approach to addressing a relatively simple environmental problem. In the 1950s, suburban sewage treatment plants were releasing their effluent (treated sewage) into the lake. This, in turn, raised the lake’s level of nutrients to the point where the lake supported excessive growth of cyanobacteria. The subsequent decomposition of cyanobacteria eventually led to an inhospitable environment for the lake’s fish and small invertebrates. Scientists predicted that the lake’s decline could be reversed if the pollution was stopped. They were correct; disposal of the sewage in another way solved the lake’s pollution problem.

Chapter 2 Environmental Laws, Economics, and Ethics Lecture Outline: I. A Brief Environmental History of the United States A. During the 18th and 19th centuries, most Americans had a frontier attitude toward nature and its resources B. Protecting forests i. Numerous men contributed to the protection of American forests throughout the 19th and 20th centuries 1. Influential artists and authors (i.e., John James Audubon, Henry David Thoreau, George Perkins Marsh) aroused widespread public interest in wildlife, ecology, and environmental change 2. Theodore Roosevelt designated 21 new national forests and removed 43 million acres of forest from logging as per the General Revision Act of 1891 ii. Utilitarian conservationists are those who view forests in terms of their usefulness for people – such as in providing jobs C. Establishing and protecting national parks and monuments i. In 1916 Congress created the National Park Service (NPS) to manage the national parks and monuments for the enjoyment of the public “without impairment” 1. Yellowstone National Park, the world’s first national park, was established in 1872 2. Today there are 58 national parks and 73 national monuments under NPS management ii. John Muir, a biocentric preservationist, was largely responsible to the establishment of Yosemite and Sequoia National Parks in California D. Conservation in the mid-20th century i. Franklin Roosevelt was an influential advocate for conservation 1. During the Great Depression he established the Civilian Conservation Corps, employing more than 175,000 men to perform various activities to protect natural resources 2. In 1935 he formed the Soil Conservation Service in response to the American Dust Bowl ii. Aldo Leopold argued persuasively for a land ethic and the sacrifices such an ethic requires in numerous writings (i.e., Game Management and A Sand County Almanac) iii. An essay written by Wallace Stegner helped create support for passage of the Wilderness Act of 1964 iv. Rachel Carson’s writings (Silent Spring) led to restrictions on the use of certain pesticides

Chapter 2 v. Paul Ehrlich’s book (The Population Bomb) raised public awareness of the dangers of overpopulation and triggered debates on how to deal effectively with population issues E. The environmental movement of the late 2oth century i. The first Earth Day, held in 1970, awakened U.S. environmental consciousness to population growth, overuse of resources, and pollution and degradation of the environment ii. Environmental awareness and the belief that individual actions could repair the damage humans were doing to Earth became a pervasive popular movement iii. By the end of the 20th century, the focus had shifted from the importance of individual actions to pressuring governments and large corporations to make environmentally appropriate decisions II. U.S. Environmental Legislation A. The Environmental Protection Agency (EPA) was formed in 1970 B. The National Environmental Policy Act (NEPA) was also signed into law in 1970 i. NEPA requires the federal government to consider the environmental impact of any proposed federal action 1. NEPA provides the basis for developing detailed environmental impact statements (EIS’s) 2. NEPA established the Council on Environmental Quality to monitor the required EISs and report directly to the president ii. NEPA revolutionized environmental protection in the United States C. Environmental policy since 1970 i. Congress has passed many environmental laws that address a wide range of issues, such as endangered species, clean water, clean air, energy conservation, hazardous wastes, and pesticides ii. Through the late 1980s and early 1990s, EPA and a number of states engaged in environmental prioritization exercises (aka, Comparative Risk Analyses), that evaluate the health, economic, and ecosystem impacts of a range of environmental issues iii. In 1994, Executive Order 12898 required that all new environmental regulations take environmental justice issues into account iv. Implementation and enforcement of environmental regulations often fall to state governments, which must send the EPA detailed plans showing how they plan to achieve regulatory goals an standards v. The last decade has witnessed increased interest in regulatory reform, in which environmental health, safety, and other regulations are selected based on cost-effectiveness III. Economics and the Environment A. Economics is the study of how people use their limited resources to try and satisfy unlimited wants i. Economists who work on environmental problems must take a systems perspective ii. Economics, as applied to public policy, relies on several precepts 1. Economics is utilitarian

Chapter 2 2. Economists assume that all individuals know what goods and services are worth to them, and spend their limited resources in a way that provides them the most utility (rational actor model) 3. In an ideal economy, resources will be allocated efficiently iii. Environmental problems arise when market failures occur due to inefficiencies and/or externalities iv. Externalities occur when the producer of a good or service does not have to pay the full costs of production B. Strategies for pollution control i. Historically, many environmental regulations have been command and control solutions 1. The EPA or other government agency requires a particular piece of equipment to be installed to limit emissions to water, air, or soil 2. Industries object that this discourages development of lower-cost alternatives that would achieve the same level of pollution control for less money ii. Preference among economists is for incentive-based or cost-benefit-based regulation such as environmental taxes, tradable permits, and emission charges 1. Environmental taxes are designed to identify and replicate the social cost of pollution 2. Tradable permits rely on identifying the optimal level of pollution 3. Emission charges are a tax on pollution (i.e., “green taxes”) iii. Cost-effectiveness analysis is an increasingly common regulatory tool and evaluates how much an established regulation will cost to achieve an outcome C. Critiques of environmental economics i. It is difficult to assess the true costs of environmental damage by pollution and the cost of abatement ii. It is not agreed upon that economics is an appropriate decision tool for environmental science 1. The risks of unanticipated environmental catastrophes may not be taken into account 2. Dynamic changes over time may not be considered D. Natural resources, the environment, and the national income accounts i. National income accounts represent the total income of a nation for a given year 1. Gross domestic product (GDP) and net domestic product (NDP) provide estimates of national economic performance used to make important policy decisions 2. These measures (GDP and NDP) are misleading and incomplete because they do not account for environmental factors, costs and benefits of pollution control and depletion of natural capital ii. Economic development experts have expressed concern that some poor countries, in attempting to raise their GDPs as quickly as possible, overexploit their natural resources and impair the environment

Chapter 2 iii. One tool that may be used alongside the GDP is the Environmental Performance Index (EPI) 1. EPI assesses a country’s commitment to environmental and resource management 2. To date, 133 countries have been assessed using EPI, the U.S. ranks 28th IV. Environmental Ethics, Values, and Worldviews A. Ethics is the branch of philosophy that is derived through the logical application of human values i. Values are the principles that an individual or society considers important or worthwhile and change as societal, cultural, political, and economic priorities change ii. Environmental ethics examines moral values to determine how humans should relate to the natural environment 1. It considers the rights of people living today, both individually and collectively, and also the rights of future generations 2. Addressing issues of environmental ethics puts us in a better position to use science, government policies, and economics for long-term environmental sustainability B. Human-centered and life-centered worldviews i. Environmental worldviews lead to behaviors and lifestyles that may or may not be compatible with environmental sustainability 1. The western worldview (expansionist worldview) is anthropocentric and utilitarian a. It aims to conquer and exploit nature as quickly as possible b. It advocates the inherent rights of individuals, accumulation of wealth, and unlimited consumption of goods and services to provide material comforts 2. The deep ecology worldview is biocentric and represents a radical shift in how humans relate themselves to the environment a. It stresses that all forms of live have a right to exist b. It advocates that humans have an obligation to themselves and to the environment, and to sharply curb human growth

Chapter 2

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

What is a life worth?

Time: Materials: Handouts:

5 minutes prep; 20 – 30 minutes in class Internet access desirable None

Procedures:

Students will explore the range of values that economists find to be implicit or regulators state as implicit in various cost-benefit calculations.

Divide students into groups of 3 – 4. First, they will try to come up with a dollar value for human lives. Each group should think about how much value society puts on a human life. Note that not all students will accept that this is a valid way to think about human lives—indeed, not all academics who work on regulatory issues think it’s valid, although most economists do. Some examples they might want to draw on are insurance settlements they may have heard of, or tradeoffs they might be familiar with. Second, they will go on-line to explore the range of values used by regulators or calculated by economists/policy analysts. Finally, they will report their findings back to the class.

Student Economists often argue that any regulation that saves lives puts an Instructions: implicit value on human lives. For example, if 100 steel mills are required to spend $10,000 on a scrubber, and those scrubbers are expected to save 2 lives, then the implicit value of one life is 100 times $10,000 divided by 2, or $500,000. Economists also estimate the value of human lives from insurance settlements—for example, how much people win or accept in wrongful death lawsuits.

Working with the assumption that this is a valid way to think about statistical lives (note that you need not believe this—just work with it for now), what value do you think an American life is worth? Are all lives “worth” the same? If not, what would make a life worth more or less?

Give examples that you think would stand up in a court of law.

After you have come up with a value or range of values, go to the internet and search for values placed on human lives. Economics and policy literature, and EPA / OSHA / FDA websites might be particularly fruitful resources. What values or ranges did you find? What do you think might account for these differences?

Specific Suggestions:

None

Objectives:

Describe how human lives are valued in regulatory policy making.

Chapter 2

Instructor Notes for In-Class Activity 2 Title:

Should Trees Have Standing?

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For/Against/Jury standard procedure. Divide class into 3 groups.

Statement: An endangered tree species has as much right to continue to exist as does the human species.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time:

Chapter 2 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Distinguish between utilitarian conservationists and biocentric preservationists.

Chapter 2

Instructor Notes for In-Class Activity 3 Title:

Satish, Kia and Marco: Who is the Environmentalist?

Time: Materials: Handouts:

5 minutes prep; 10 minutes in class None Character Descriptions

Procedures:

Hand out the three character descriptions, or post them. Have students spend 5 – 10 minutes working individually to answer the question. Then have students discuss their answers. You may want to try a vote or tally for each of the hypothetical individuals.

Student Consider the character descriptions on the handout or posted on Instructions: PowerPoint. Which of these individuals, if any, is an “environmentalist?”

Why? What does this imply about environmentalism?

Specific Suggestions:

Make your own examples, especially real people that your students may know.

Objectives:

Describe the complexity of environmental ethics and the meaning of “environmentalism.”

Chapter 2 In-Class Activity 3: Handout Consider the three character descriptions below. Which of these individuals, if any, is an “environmentalist?” Why do you think so? Who has done the most to reduce environmental degredation? What does this imply about environmentalism?

1. Marco is an environmental studies major at a local College. He is active in the two campus student environmental organizations, and is trying to set up a recycling center on campus. He has been saving up his income from working at a bookstore to take a two week ecotourism trip to Costa Rica after graduation.

2. Kia is a stock analyst. She has a 40 minute commute each way to her job in the city. She carpools with one other person in a Chevy Suburban. She makes a decent salary, and every year sends donations to Greenpeace, the Sierra Club, and several local environmental groups. She always recycles cans, bottles and newspapers, and as a vegetarian tries to buy organic foods when possible.

3. Satish is an engineer at a pulp and paper mill. He can often be heard grumbling about the environmental regulations his plant faces, and the government agents who come in to inspect. He recently won an award for figuring out a way to divert waste heat from the plants power generation system to assist in drying out the paper as is goes though the system. This saves the company about $50,000 per year, mostly in reduced energy costs and fees for avoided heat pollution in the local river. Several years ago he won a similar award for finding that some of the pulp waste could be used to fertilize orchards.

Chapter 2

Instructor Notes for In-Class Activity 4 Title:

Political Environmental Cartoon Time

Time: Materials: Handouts:

5 minutes prep; 60-90 minutes outside of class time Internet access desirable None

Procedures:

Students will explore the world of political cartoons.

This activity can be done in groups or by an individual. Have the students search the internet, news papers, books or other information sources for cartoons dealing with the environment and the area politics play in making environmental policy. Students are to mount their cartoons, you can determine if you want 1, 5 or 10 and have them mount them on a poster board and then you have a poster session involving cartoons and the environment. A variation of this activity would be to divide the student into groups of 4 or 5 and have the students put together a cartoon notebook. These notebooks will be graded by the classroom and could be on display in the library for other students to enjoy.

Student Our society often finds humor in issues and the environment is a great Instructions: place to find humorous cartoons. It is your mission to search for the internet, books, newspapers and other sources for cartoons pertaining to the environment, environmental policies etc After you have come up with (x number) of cartoons, you need to put a poster presentation together for display in the school library. Each team (or individual) will be responsible for one poster.

The alternative presentation would be to either have them put them into a power point presentation or in a notebook that will also be displayed in the library.

This is an activity the students can have fun with and also use their creative ways to present their finding.

Specific Suggestions:

None

Objectives:

Relate how the public views and sees this type of media on the environment.

Chapter 2

Answers to Critical Thinking and Review End of Chapter Questions: 1. Briefly describe each of the following aspects of U.S. environmental history: protection of forests; establishment and protection of national parks and monuments, conservation in the mid20th century; and the environmental movement of the late 20th century.

Ans: During the 19th century, many U.S. naturalists began to voice concerns about conserving natural resources. In 1875 a group of public-minded citizens formed the American Forestry Association, with the intent of influencing public opinion against the wholesale destruction of America's forests. Sixteen years later, in 1891, the General Revision Act gave the president the authority to establish forest reserves on federally owned land. Roosevelt appointed Gifford Pinchot (1865-1946) as the first head of the U.S. Forest Service. Pinchot supported expanding the nation's forest reserves and managing forests scientifically.

Congress established the world's first national park (Yellowstone National Park) in 1872 after a party of Montana explorers reported on the natural beauty of the canyon and falls of the Yellowstone River. In 1906 Congress passed the Antiquities Act, which authorized the president to set aside, as national monuments sites, areas that had scientific, historic, or prehistoric importance. By 1916 there were 13 national parks and 20 national monuments.

During his administration Franklin Roosevelt (1882-1945) established the Civilian Conservation Corps, which employed more than 175,000 men to plant trees, make paths and roads in national parks and forests, build dams to control flooding, and perform other activities to protect natural resources. In 1935 President Roosevelt formed the Soil Conservation Service in response to drought conditions across the Great Plains. Other people that had a profound effect in this time period include, Aldo Leopold who wrote about humanity's relationship with nature, Wallace Stegner, who helped create support for passage of the Wilderness Act of 1964, Rachel Carson, who published Silent Spring, alerting the public to the dangers of uncontrolled pesticide use, and Paul Ehrlich, who wrote The Population Bomb, which raised the public's awareness of the dangers of overpopulation.

There was no generally perceived environmental movement until the spring of 1970, when the first nationally celebrated Earth Day event took place. This event awakened U.S. environmental consciousness to population growth, overuse of resources, and pollution and degradation of the environment. On Earth Day 1970, an estimated 20 million people in the United States demonstrated their support of environmental quality by planting trees, cleaning roadsides and riverbanks, and marching in parades.

2. Describe the environmental contributions of two of the following: George Perkins Marsh, Theodore Roosevelt, Gifford Pinchot, John Muir, Aldo Leopold, Wallace Stegner, Rachel Carson, and Paul Ehrlich.

Ans: George Perkins Marsh wrote about humans as agents of global environmental change.

Theodore Roosevelt removed millions of areas of forest from logging and appointed Gifford Pinchot as the first head of the U.S. Forest Service. Pinchot supported expanding the nation's forest reserves and managing forests scientifically. The Yosemite and Sequoia National Parks

Chapter 2 were established, largely in response to the efforts of naturalist John Muir. In A Sand County Almanac, Aldo Leopold wrote about humanity's relationship with nature. Wallace Stegner helped create support for passage of the Wilderness Act of 1964. Rachel Carson published Silent Spring, alerting the public to the dangers of uncontrolled pesticide use. Paul Ehrlich wrote The Population Bomb, which raised the public's awareness of the dangers of overpopulation 3. If you were a member of Congress, what legislation would you introduce to deal with each of these problems? a. Toxic materials from a major sanitary landfill are polluting rural drinking water wells. b. Acid rain from a coal-burning power plant in a nearby state is harming the trees in your state. Loggers and foresters are upset. c. Oceanfront property is at risk from sea-level rise caused by global warming.

Ans: Answers will vary 4. Following the 2010 oil platform collapse and associated oil spill in the Gulf of Mexico, Congress began considering new laws regulating deep-ocean oil drilling. Do you think command and control or incentive-based regulations would be more effective? Explain Ans: Answers will vary but should include (Historically command and control solutions have been used by the EPA to require the installation of a particular piece of equipment to limit emissions. Incentive-based regulations have taken the approach of using environmental taxes or tradable permits.)

5. Based on what you have learned in this chapter, do you think the economy is part of the environment, or is the environment part of the economy? Explain your answer.

Ans: Answers will vary.

6. Explain how environmental taxes can be revenue neutral.

Ans: Many countries in Europe have placed taxes on non-renewable resources, such as heating oil, gasoline, and natural gas. At the same time income taxes in these countries were lowered.

Increases in taxes on carbon emissions and fuel resources are usually “revenue neutral,” since they are offset by reductions in other taxes or rebates.

8. Can economic approaches to environmental management adequately account for the complex interactive systems that make up the environment? Why or why not?

Ans: Answers will vary.

9. The Environmental Performance Index has detractors among both environmentalists and industry groups. Based on what you’ve learned in this chapter, suggest reasons for each.

Ans: Answers will vary.

Chapter 2 10. Graph the marginal cost of pollution, the marginal cost of pollution abatement, and the optimum amount of pollution.

11. Describe how environmental destruction in formerly communist countries relates to natural capital.

Ans: Natural capital is all of Earth’s resources and processes that sustain living organisms, including humans. Natural capital includes minerals, forests, soils, groundwater, clean air, wildlife, and fisheries. Over the previous decades, formerly communist countries have ignored the value of natural capital. Water was so poisoned from raw sewage and chemicals that it could not be used for industrial purposes. Unidentified chemicals leaked out of dumpsites into the surrounding soil and water, while nearby, fruits and vegetables were grown in chemical-laced soil. Power plants emitted soot and sulfur dioxide into the air, producing a persistent chemical haze. Buildings and statues eroded, and entire forests died because of air pollution and acid rain.

Crop yields fell despite intensive use of chemical pesticides and fertilizers. One of the most polluted areas in the world was the “Black Triangle,” which consists of the bordering regions of the former East Germany, northern Czech Republic, and southwest Poland.

12. State whether each of the following statements reflects the Western worldview, the deep ecology worldview, or both: a. Species exist for humans to use. b. All organisms, humans included, are interconnected and interdependent. c. There is a unity between humans and nature. d. Humans are a superior species capable of dominating other organisms. e. Humans should protect the environment. f. Nature should be used, not preserved. g. Economic growth will help Earth manage an expanding human population. h. Humans have the right to modify the environment to benefit society. i. All forms of life are intrinsically valuable and have the right to exist.

Ans: Western worldviews include a, d, f, g, h Deep ecology worldviews include b, c, e, i 13. What is this cartoon trying to say? When do you think this cartoon was published?

Chapter 2

Ans: Answers will vary.

14. Do you agree or disagree with the idea that climate change is an environmental justice issue?

Explain your position.

Ans: Answers will vary.

Answers Review Questions A Brief Environmental History of the United States 1. Which occurred first in the U.S. environmental movement: concerns about forest conservation or concerns about pollution?

Concerns about forest conservation preceded concerns about pollution in the U.S. environmental movement.

2. Describe how an individual can influence U.S. environmental history or policy.

Over the course of history, individuals have greatly influenced U.S. environmental policy. For example, John Muir led the way in establishing some of the country’s first national parks, and the writings of Aldo Leopold helped establish taxes which went towards funding wildlife management and research. Aldo Leopold’s work also had a profound influence on another influential individual, Wallace Stegner. Stegner can be credited with creating support for the passage of the Wilderness Act of 1964. Likewise, the writings of Rachel Carson heightened public awareness and concerns about the dangers of uncontrolled use of DDT and other pesticides. This eventually led to government restrictions on the use of certain pesticides in the United States.

3. Explain how the attitudes of utilitarian conservationists toward environmental policy differ from those of biocentric preservationists.

Chapter 2 A utilitarian conservationist is a person who values natural resources because of their usefulness for practical purposes, but uses them sensibly and carefully. Examples of utilitarian conservationists include Theodore Roosevelt and Gifford Pinchot, both of whom were instrumental in conserving our nation’s forests. Their views have led to modern day national forests that are managed for multiple uses (i.e., biological habitats, recreation, timber harvest, and cattle grazing). On the other hand, biocentric preservationists (i.e., John Muir) do not believe in conserving wild areas for practical purposes. They believe in protecting nature because all forms of life deserve respect and consideration.

U.S. Environmental Legislation 1. Which law is the cornerstone of U.S. environmental law? Why? The National Environmental Policy Act (NEPA), passed in 1970, is the cornerstone of U.S. environmental law, and revolutionized environmental protection in the United States. NEPA states that the federal government must consider the environmental impact of any proposed federal action. It also provides the basis for developing detailed environmental impact statements (EISs) to accompany every federal recommendation or legislative proposal. While legislation to manage many environmental problems existed before 1970, NEPA provided the regulatory system necessary to create and enforce effective environmental policy.

2. In what ways has the U.S. environment improved as the result of regulations?

Despite imperfections, U.S. environmental legislation has had overall positive effects on the environment. Since 1970: (1) twenty-three national parks have been established; (2) soil erosion has been reduced by nearly 60%; (3) many previously endangered species are better off, including the American alligator and the California gray whale; (4) energy efficiency and conservation technology have improved markedly for buildings, vehicles, and consumer products; (5) both emissions and ambient concentrations of six important air pollutants have dropped by at least 25%; (6) levels of wet sulfate, a major component of acid rain, have dropped by about 33%; (7) violations of EPA drinking water standards have decreased; (8) greater amounts of municipal solid waste was combusted for energy recovery or recovered for composting or recycling; and (9) the human exposures to contamination by hazardous waste sites have been reduced.

Economics and the Environment 1. What do economists mean by “efficient” regulation?

Economists assume that individuals behave as rational actors who seek to minimize utility. Groups of individuals behaving according to these assumptions result in economic efficiency, the greatest possible total societal benefit. Solutions that are inefficient will spend more on abatement than the pollution costs or will spend less on abatement than pollution reductions are worth. Optimal efficiency would be at the point in which the marginal cost of pollution is equal to the marginal cost of abatement.

Chapter 2

2. When might command and control regulations be more or less effective than economicsbased policies?

In command and control regulations, the EPA or other government agency usually requires a particular piece of equipment to be installed to limit emissions to water, air, or soil. In effect, they are pollution-control laws that require specific technologies. This type of regulation may be more or less effective than economics-based policies when the assessment of the true cost of environmental damage by pollution and pollution abatement is incorrect in economics-based policies.

3. What does the EPI measure that the GDP does not?

The Environmental Performance Index (EPI) assesses a country’s commitment to environmental and resource management. The EPI is a more comprehensive measure of national income accounting than the Gross Domestic Product (GDP) because it includes estimates of both natural resource depletion and the environmental costs of economic activities. Environmental factors are not incorporated into the assessment of the GDP. Environmental Justice 1. Is environmental justice a local issue, an international issue, or both? Explain.

Environmental justice is both a local issue and an international issue. It applies to all countries as well as to individuals. For example, it was necessary to develop the Basal Convention to restrict the export of solid and hazardous waste from highly developed countries to developing nations. Additionally, climate change is an international environmental justice issue. While highly developed countries are responsible for the majority of fossil fuel consumption, the adverse effects are felt by the entire world’s population (which includes a large percentage of very poor populations).

Environmental Ethics, Values, and Worldviews 1. What is environmental ethics?

Environmental ethics is a field of applied ethics that considers the moral basis of environmental responsibility and the appropriate extent of this responsibility. It examines moral values to determine how humans should relate to the natural environment.

2. What are worldviews? How do Western and deep ecology worldviews differ?

Worldviews are commonly shared perspectives based on a collection of our basic values that help us make sense of the world, understand our place and purpose in it, and determine right and wrong behaviors. The Western worldview is an understanding of our place in the world based on human superiority and dominance over nature, the unrestricted use of natural resources, and increased economic growth to manage an

Chapter 2 expanding industrial base. It is an anthropocentric and utilitarian worldview.

Conversely, the deep ecology worldview is an understanding of our place in the world based on harmony with nature, a spiritual respect for life, and the belief that humans and all other species have an equal worth. It is a biocentric worldview, and views humans as one species among others.

Chapter 3 Ecosystems and Energy Lecture Outline: I. What is Ecology?

A. Ernst Haeckel developed the concept of ecology in the 19th century i. Ecology literally means “the study of one’s house”; it is the broadest field within the biological sciences , and is linked to many other disciplines (i.e., geology, earth science, chemistry, physics) ii. It examines the systems that include interactions among organisms and between organisms and their abiotic environment 1. The biotic environment includes all living organisms 2. The abiotic environment includes living space, temperature, sunlight, soil, wind and precipitation B. Ecologists are most interested in the levels of biological organization that include or are above the level of the individual organism i. A group of similar organisms whose members freely interbreed with one another in the wild to produce fertile offspring is termed a species ii. A population is a group of organisms of the same species that live in the same area at the same time iii. A natural association that consists of all the populations of different species that live and interact within an area at the same time is called a community iv. A community and its physical environment comprise an ecosystem 1. An ecosystem is a system in which all of the biological, physical, and chemical components of an area form a complex, interacting network of energy flow and materials cycling 2. Ecosystem processes collectively regulate global cycles of water, carbon, nitrogen, phosphorus, and sulfur essential to the survival of humans and all other organisms C. Landscape ecology is a subdiscipline of ecology i. It studies ecological processes that operate over large areas ii. A landscape is a region that includes several interacting ecosystems D. Ecologists who study the biosphere examine global interrelationships among Earth’s atmosphere, land, water, and organisms i. The parts of Earth’s atmosphere, ocean, land surface, and soil that contain all living organisms is termed the biosphere ii. The atmosphere is a gaseous envelope surrounding Earth iii. The hydrosphere is Earth’s supply of water iv. The lithosphere is the soil and rock of Earth’s crust II. The Energy of Life A. Energy is the capacity or ability to do work i. Energy exists in several forms: chemical radiant, thermal, mechanical, nuclear, and electrical

Chapter 3 ii. Energy can exist as stored energy (potential) or as the energy of motion (kinetic) B. The study of energy and its transformations is called thermodynamics i. In thermodynamics, the word system is used to refer to a group of atoms, molecules, or objects being studied 1. A closed system is self-contained and isolated; it does not exchange energy with its surroundings 2. An open system exhibits an exchange of energy with its surroundings ii. The first law of thermodynamics holds that energy cannot be created or destroyed, although it can change from one form to another iii. The second law of thermodynamics holds that when energy is converted from one form to another, some of it is degraded into heat, a less usable form that disperses into the environment 1. The less usable energy is more diffuse, or disorganized; entropy is a measure of this disorder or randomness 2. No process requiring an energy conversion is ever 100% efficient because much of the energy is dispersed as heat, resulting in an increase in entropy C. Photosynthesis and cellular respiration i. Photosynthesis is the biological process in which light energy from the sun is captured and transformed into the chemical energy of carbohydrate (glucose) molecules 1. 6CO2 + 12H2O + radiant energy --> C6H12O6 + 6H2O +6O2 2. Plants, some bacteria, and algae perform photosynthesis ii. The chemical energy that plants store in carbohydrates and other molecules is released within cells of plants, animals, or other organisms through cellular respiration 1. In aerobic cellular respiration, molecules such as glucose are broken down in the presence of oxygen and water a. C6H12O6 +6O2 + 6H2O --> 6CO2 + 12H2O + energy 2. Anaerobic bacteria that live in waterlogged soil, stagnant ponds, or animal intestines respire in the absence of oxygen D. Chemosynthesis is the process by which energy produced from inorganic raw materials such as enzymes, hydrogen sulfide and oxygen; water and sulfur/sulfate are additional byproducts III. The Flow of Energy Through Ecosystems A. Energy flow is the passage of energy in a one-way direction through an ecosystem B. Producers, consumers, and decomposers i. Producers (aka autotrophs) 1. In photosynthesis, producers use the energy from sunlight to make organic molecules from carbon dioxide and water 2. Plants, algae and certain types of bacteria are important producers ii. Consumers (aka heterotrophs) 1. Consumers obtain energy when they eat producers or other consumers a. Consumers that eat producers are primary consumers (herbivores)

Chapter 3 b. Secondary consumers (carnivore) eat primary consumers c. Tertiary consumers (top carnivores) eat secondary consumers 2. Omnivores eat a variety of organisms 3. Detritus feeders (detritivores) consume organic matter that includes animal carcasses, leaf litter, and feces iii. Decomposers (aka saprotrophs) 1. Wastes and dead organic material from producers and consumers supply decomposers (i.e., bacteria, fungi) with energy 2. Bacteria and fungi are important decomposers C. The path of energy flow: who eats whom in ecosystems i. In an ecosystem, energy flow occurs in food chains, in which energy from food passes from one organism to the next in a sequence 1. Energy enters ecosystems from an external source (the sun), flows linearly, and exits as heat loss 2. Each level in a food chain is termed a trophic level a. Producers (photosynthetic organisms) form the first trophic level b. Primary consumers (herbivores) form the second trophic level c. Secondary consumers (carnivores) form the third trophic level d. Decomposers occur at every step in a food chain ii. Simple food chains rarely occur in nature, a food web is a more realistic model D. Ecological pyramids i. Ecological pyramids graphically represent the relative energy values of each trophic level 1. A pyramid of numbers show the number of organisms at each trophic level in a given ecosystem 2. A pyramid of biomass illustrates the total biomass at each successive trophic level a. Biomass is a quantitative estimate of the total mass of living material b. Biomass indicates the amount of fixed energy at a particular time 3. A pyramid of energy illustrates the energy content, often expressed as kilocalories per square meter per year, of the biomass at each trophic level E. Ecosystem productivity i. The gross primary productivity (GPP) of an ecosystem is the rate at which energy is captured during photosynthesis ii. Net primary productivity (NPP) is the energy in plant tissues after cellular respiration has occurred 1. Only the energy represented by NPP is available as food for an ecosystem’s consumers 2. Ecosystems differ strikingly in their productivities (NPP) iii. Human impact on NPP

Chapter 3 1. Humans consume far more of Earth’s resources than any other of the millions of animal species (approximately 32% of the annual NPP of land-based ecosystems) 2. Humans only represent 0.5% of the total biomass of all consumers on Earth

Chapter 3

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Where Does the Energy Go?

Time: Materials: Handouts:

1 minute prep; 5 – 10 minutes in class Superball None

Procedures:

Bring a large superball to class. Drop it from as high as you can reach.

Ask students to describe where the energy came from, and what happened to the energy over time. (Note: always be sure to give students a minute or two to think before responding!)

Special notes: it is often useful to be very specific when describing the process to students. Note that the overall result is that ALL of the energy (at least from the Terran perspective) began as insolation, and ended as waste heat in the ground. Some plants absorbed the insolation, photosynthesis stored the energy in chemical bonds, you ate some toast that contained the chemical bonds, your body moved the energy into other chemical bonds and then to kinetic energy. Once you held the ball up high, it represented potential energy. You dropped the ball, and the potential energy converted into kinetic energy, with graduate losses through friction and inelastic collisions with the ground. Eventually, the ball lies still on the floor. At each step, energy became less useful, but was never destroyed.

Student None Instructions: Specific For spryer instructors, jump down from a chair, and ask the same Suggestions: question.

Objectives:

To describe the implications of the second law of thermodynamics

Chapter 3

Instructor Notes for In-Class Activity 2 Title:

Depicting an Energy System

Time: Materials: Handouts:

5 minutes prep; 10 minutes in class None None

Procedures:

None

Student Working in groups of 3-4, create a drawing that depicts how energy gets Instructions: from the sun to an eagle in mid-flight. Be specific about the different forms of energy—potential, chemical bonds, kinetic, waste heat.

Be sure to account for all energy, keeping in mind that energy is neither created nor destroyed, but does become less useful with each step.

Finally, if energy is neither created nor destroyed, and energy comes in constantly from the sun, why doesn’t the system keep getting hotter and hotter?

Specific None Suggestions: Objectives:

Describe energy flow through an ecosystem.

Chapter 3

Instructor Notes for In-Class Activity 3 Title:

How Much Acreage of Grain is Needed to Feed a Barn Owl?

Time: Materials: Handouts:

10 minutes prep; 20 minutes in class None None

Procedures:

Have students solve the problem below, which requires that they calculate the amount of grain that is needed to keep a barn owl alive.

Use this as a basis for discussing trophic levels and pyramids of energy and numbers.

Student Working in groups of 3-4, answer the following question: Instructions: Suppose that you discover that a farmer’s barn has an owl living in it. The owl is full grown, and weighs about 2 kg. It lives entirely on small animals which in turn feed on grain stored in the barn.

How much acreage of grain is required to keep this barn owl fed?

Some things for which you will have to either make assumptions or find data: • How much does a 2 kg barn owl eat?

• How much do the mice and other grain eating creatures eat • How much grain can be raised on a give area of farmland?

Specific Suggestions:

If you have time, have students then estimate the area that might be required to maintain a pair of predatory birds. What additional assumptions / data do they need?

Objectives:

Describe how trophic levels relate to each other

Chapter 3

Instructor Notes for In-Class Activity 4 Title:

Producers, Consumers and Decomposers Identification Game

Time: Materials:

60 minutes; 20 – 30 minutes in class Pictures of animals, plants, worms, bacteria etc. (the classes of producers, consumers and decomposers None

Handouts: Procedures:

Cut out pictures from the internet, magazines and other sources of pictures of different plants, fruit, worms, birds, animals, fish etc. It would be helpful to laminate these pictures. The second part would be to laminate the sets of titles: Producers, Consumers and Decomposers. You should make enough for 20 pictures a team. A team would consist of 4 or five individuals.

Divide the students into teams of 4 or 5 students. Have the pictures in a folder along with the three titles (Producers, Consumers and Decomposers). When you say go, the students must sort the pictures under the three titles. The team who finishes first wins. However, if they don’t have the pictures under the right title, they receive points off. The team who correctly places the pictures under the correct titles the quickest wins the game. The Point system is as follows: • 1 point for correct answer • 1 point off for no answer (this would be pictures that were not placed when the first team all stood up) • 2 points off for wrong answer.

Student When the teacher says “GO” the students are to take the file from the Instructions: center of the table and place all the pictures under the correct titles (Producers, Consumers and Decomposers). After all the pictures in the folder have been placed under the titles the students all stand up. The first team with all students standing up wins if they have correctly placed the pictures under the correct category.

Specific Every team member must stand when the task is complete. The first team Suggestions: with all members standing will be the one to win if they have the most points. A team who stands up second or third could still win because the teams finished before them might have some misplaced pictures.

Before the activity, make sure the students understand the difference between a Consumer, Producer and a Decomposer. For example if a student puts an Eagle in the Decomposer pile that would be a wrong answer. However, there maybe an instance where a picture falls within two different categories at this point the students can make a case why they chose their picture as a consumer or a producer etc. If they have a valid case, points should be awarded.

Objectives:

Identify different producers, consumers and decomposers.

Chapter 3

Instructor Notes for In-Class Activity 5 Title:

Creative Categories

Time: Materials: Handouts:

10 minutes prep; 60 – 90 minutes outside of class None None

Procedures:

Divide the class into three groups, each group will be a class either a Consumer, Producer or Decomposer. Assign each group to search out for pictures of animals, plants, bacteria, worms, fish, birds that would be classified as a consumer, producer or decomposer. When each team collects about 20 pictures they are to mount them on a poster board colleague and present their poster to their fellow classmates.

Student Working in three groups of equal number of students Instructions: It is your mission to find pictures of animals, birds, fish, bacteria, worms, plants that would fall into the classification of your category which would be either a producer, consumer or decomposer. After you find the necessary pictures please mount them on a poster board for a poster presentation to the class. Be creative.

Specific Suggestions:

For extra suggestion the group should define their category and what makes an organisms a consumer, producer or a decomposer.

Objectives:

Describe and identify the different organism as a consumer, producer or decomposer.

Chapter 3

Answers to Critical Thinking and Review End of Chapter Questions: 1. Draw a food web containing organisms found in a Chesapeake Bay salt marsh.

Ans: Answers will vary 2. Describe the science of ecology?

Ans: Ecology is the study of systems that include interactions among organisms and between organisms and their abiotic environment.

3. Which scientist—a population ecologist or a landscape ecologist—would be most likely to study broad-scale environmental issues and land management problems? Explain your answer.

Ans: Landscape ecology is a subdiscipline of ecology that studies ecological processes that operate over large areas. Landscape ecologists examine the connections among ecosystems found in a particular region. Landscapes are based on larger land areas that include several ecosystems. Population ecologists work on a smaller scale. A population ecologist might study a population of polar bears or a population of marsh grass.

4. What is energy? How are the following forms of energy significant to organisms in ecosystems: (a) radiant energy, (b) mechanical energy, (c) chemical energy?

Ans: Energy is the capacity or ability to do work. Radiant energy is energy, such as radio waves, visible light, and X rays, which is transmitted as electromagnetic waves. Radiant energy is significant for providing energy for photosynthesis and visible light for sight. Mechanical energy is energy in the movement of matter, necessary for animals capturing food. Chemical energy is energy stored in the bonds of molecules; for example, food contains chemical energy. Thermal energy is heat energy that flows from an object with a higher temperature (the heat source) to an object with a lower temperature (the heat sink). Within ecosystems and organisms the different forms of energy are necessary for biological work such as growing, moving, reproducing, and maintaining and repairing damaged tissues.

5. Give two examples of potential energy, and in each case tell how it is converted to kinetic energy.

Ans: Energy can exist as stored energy—called potential energy—or as kinetic energy, the energy of motion. Think of potential energy as an arrow on a drawn bow, which equals the work the archer did when drawing the bow to its position. When the string is released, the bow's potential energy is converted to the arrow's kinetic energy of motion. Similarly, the cordgrass that a meadow vole eats has chemical potential energy in the bonds of its molecules; as molecular bonds are broken, this energy is converted to kinetic energy and heat as the meadow vole swims in the salt marsh. Thus, energy changes from one form to another.

Chapter 3 6. Is this an example of an open system or a closed system? Explain your answer.

Ans: This is an example of an open system because an open system exhibits an exchange of energy with its surroundings.

7. How is the first law of thermodynamics related to the movement of an automobile?

Ans: The gasoline that you put in your automobile has potential energy stored as chemical energy in its molecular bonds. As gasoline is burned it releases energy, part of this energy is captured and transformed into mechanical energy to move the car forward. The remainder of the energy is lost as heat energy. The first law of thermodynamics explains how chemical energy converts to mechanical energy.

8. Give an example of a natural process in which order becomes increasingly disordered.

Ans: As a result of the second law of thermodynamics, no process requiring an energy conversion is ever 100% efficient because much of the energy is dispersed as heat, resulting in an increase in entropy. An automobile engine, which converts the chemical energy of gasoline to mechanical energy, is between 20 and 30% efficient. That is, only 20 to 30% of the original energy stored in the chemical bonds of the gasoline molecules is actually transformed into mechanical energy, or work. In our cells, energy use for metabolism is about 40% efficient, with the remaining energy given to the surroundings as heat.

9. How are photosynthesis and cellular respiration related? Write the overall equation for both processes.

Ans: Photosynthesis is the biological process in which light energy from the sun is captured and transformed into the chemical energy of carbohydrate molecules. The chemical energy that plants store in carbohydrates and other molecules is released within the cells of plants, animals, and other organisms through cellular respiration.

Chapter 3 Photosynthesis 6CO2 +12H2O + radiant energy yields C6H12O6 + 6H2O + 6 O2 Cellular respiration C6H12O6 + 6H2O + 6 O2 yields 6CO2 +12H2O

10. Why is the concept of a food web generally preferred over a food chain?

Ans: Simple food chains rarely occur in nature because few organisms eat just one kind of organism. More typically, the flow of energy and materials through an ecosystem takes place in accordance with a range of food choices for each organism involved. In an ecosystem of average complexity, numerous alternative pathways are possible. A hawk eating a rabbit is a different energy pathway than a hawk eating a snake. A food web is a more realistic model of the flow of energy and materials through an ecosystem.

11. Could you construct a balanced ecosystem that contained only producers and consumers? only consumers and decomposers? only producers and decomposers? Explain the reasons for your answers.

Ans: Ecosystems must contain a balanced representation of producers, consumers, and decomposers, all of which have indispensable roles in ecosystems. Producers provide both food and oxygen for the rest of the community. Consumers play an important role by maintaining a balance between producers and decomposers. Detritus feeders and decomposers are necessary for the long-term survival of any ecosystem because, without them, dead organisms and waste products would accumulate indefinitely.

12. Label these parts in the following simple ecosystem: producer, primary consumer, secondary consumer, decomposer. Which of these organisms photosynthesizes? Which carry out cellular respiration? Which give off heat into their surroundings?

Ans: The plant is a producer and carries out both photosynthesis and cellular respiration. The Bird can be either a primary consumer when it eats the berries on the plant or a secondary consumer when it eats insects. The bird only carries out cellular respiration. The earthworms are decomposers and only carryout cellular respiration. All release heat into their environments.

13. Suggest a food chain with an inverted pyramid of numbers—that is, greater numbers of organisms at higher than at lower trophic levels.

Ans: Inverted pyramids of numbers, in which higher trophic levels have more organisms than lower trophic levels, are often observed among decomposers, parasites, tree-dwelling herbivorous insects, and similar organisms.

Chapter 3

14. Is it possible to have an inverted pyramid of energy? Why or why not?

Ans: It is not possible to have an inverted pyramid of energy. Energy pyramids show that most energy dissipates into the environment when going from one trophic level to the next. Less energy reaches each successive trophic level from the level beneath it because organisms at the lower level use some energy to perform work, and some is lost.

15. Relate the pyramid of energy to the second law of thermodynamics.

Ans: According to the second law of thermodynamics, when energy is converted from one form to another, some of it is degraded into heat. No biological process is ever 100% efficient so as energy is transferred from one trophic level to the next there is less energy available to the higher trophic level. Energy pyramids show that most energy dissipates into the environment when going from one trophic level to the next.

16. What is NPP? Do humans affect the global NPP? If so, how? If not, why?

Ans: NPP is net primary productivity. Energy in plant tissues after cellular respiration has occurred is net primary productivity. NPP is productivity after respiration losses are subtracted.

Humans consume far more of earth’s resources than any other of the millions of animal species.

It is estimated that humans use 32% of the annual NPP of land-based ecosystems. That is a huge amount considering that humans represent about 0.5% of the total biomass of all consumers on earth.

17. Alcohol fuels produced from corn are often considered a climate friendly answer to our energy needs. Explain why a large-scale increase in the production of corn to provide fuel could have a negative or even catastrophic impact on ecosystems.

Ans: If we grow corn and other biomass crops on a large scale for fuel, then we will be taking an even larger share of global NPP, which would leave even less for the planet’s organisms. At some point, our use of global NPP will compromise Earth’s systems that sustain us. Indeed, we may have already exceeded the sustainable consumption of NPP.

Answers to Review Questions What is Ecology?

1. What is ecology?

Ernst Haeckel, a 19th century scientist, developed the concept of ecology. Ecology is the study of systems that include interactions among organisms and between organisms and their abiotic environment.

Chapter 3

2. What is the difference between a community and an ecosystem? Between an ecosystem and a landscape?

A community is defined as a natural association that consists of all the populations of different species that live and interact within an area at the same time. An ecosystem is a more inclusive term than community; it includes all the biotic interactions of a community as well as the interactions between organisms and their abiotic environment.

A landscape encompasses a region that includes several interacting ecosystems.

The Energy of Life 1. Distinguish among energy, work, and heat.

Energy is the capacity or ability to do work, and is required for biological work such as growing, moving, reproducing, and maintaining and repairing damaged tissues. Energy exists in several forms: chemical, radiant, thermal, mechanical, nuclear, and electrical.

Biologists generally express energy in units of work (kilojoules, kJ) or units of heat (kilocalories, kcal).

2. Is water stored behind a dam an example of potential or kinetic energy? What would cause the water to convert to the other form of energy?

Water stored behind a dam is an example of potential energy. The water could convert to kinetic energy (i.e., the energy of motion) if the dam were to break or be opened and water was released.

3. Is a rabbit an example of a closed system or an open system? Why? A rabbit is an example of an open system because it exchanges energy with its surroundings. It receives energy from the food it eats, and releases energy in the form of cellular respiration and other waste products. Closed systems are very rare in nature.

4. When coal is burned in a power plant, only 3% of the energy in the coal is converted into light in a lightbulb. What happens to the other 97% of the energy? Explain your answer using the laws of thermodynamics.

There are two laws regarding energy that apply to all things in the universe, the first and second laws of thermodynamics. The first law of thermodynamics states that energy cannot be created or destroyed, although it can change from one form to another.

Therefore, according to the first law of thermodynamics, the energy that is released when coal is burned in a power plant is converted into electricity, and again converted into the light that shines in a the lightbulb. However, when this energy is converted from the burning coal, to electricity, to light, some of it is degraded into heat. In the case of the

Chapter 3 lightbulb, 97% of this energy actually disperses into the environment as heat. This supports the second law of thermodynamics which states that when energy is converted from one form to another, some of it is degraded into heat, a less usable form that disperses into the environment.

5. Distinguish between photosynthesis and cellular respiration. Which organisms perform each process?

Photosynthesis is the biological process in which light energy from the sun is captured and transformed into the chemical energy of carbohydrate molecules. It is performed by plants, some bacteria, and algae. Cellular respiration makes the chemical energy stored in carbohydrate molecules available to the cell for biological work. All organisms, including plants, use cellular respiration to obtain energy.

The Flow of Energy Through Ecosystems 1. What is a food web?

A food web is a representation of the flow of energy and materials through an ecosystem.

It represents the interlocking food chains and feeding relationships that indicate how a community is organized.

2. How does energy flow through a food web consisting of producers, consumers, and decomposers?

Energy that enters an ecosystem from the sun always flows linearly. During every energy transaction, some energy is lost to biological systems as it disperses into the environment as heat. Yet, organisms within this energy transaction each have a range of food choices available to them, so simple food chains (i.e., producer -> consumer -> decomposer) rarely occur in nature. More typically, in an ecosystem of average complexity, numerous pathways are possible and the flow of energy takes place in accordance. For example, a consumer may consume a producer or another consumer.

That consumer may be consumed by decomposers or another consumer. And so on.

3. What is a pyramid of energy?

A pyramid of energy illustrates the energy content of the biomass of each trophic level in an ecosystem. It demonstrates that most energy dissipates into the environment when going from one trophic level to the next. Energy pyramids help explain why there are so few trophic levels, and that food webs are short because of the dramatic reduction in energy content at each trophic level.

4. What is gross primary productivity? Net primary productivity?

Chapter 3 Gross primary productivity (GPP) is the total amount of photosynthetic energy that plants capture and assimilate in a given period. Net primary productivity (NPP) is the productivity after respiration losses are subtracted. NPP represents the rate at which organic matter is actually incorporated into plant tissues for growth. NPP = GPP – plant cellular respiration

Chapter 4 Ecosystems and the Physical Environment Lecture Outline: I. Biogeochemical cycles A. The carbon cycle i. The global movement of carbon between organisms and the abiotic environment is known as the carbon cycle 1. Carbon is present in the atmosphere as carbon dioxide(CO2), the ocean as carbonate and bicarbonate (CO32-, HCO3-) and sedimentary rock as calcium carbonate (CaCO3) 2. Proteins, carbohydrates, and other molecules essential to life contain carbon 3. Carbon makes up approximately 0.04% of the atmosphere as a gas ii. Carbon primarily cycles through both biotic and abiotic environments via photosynthesis, cellular respiration and combustion (CO2) 1. Photosynthesis incorporates carbon from the abiotic environment (CO2) into the biological compounds of producers (sugars) 2. Producers, consumers and decomposers use sugars as fuel and return CO2 to the atmosphere in a process called cellular respiration 3. Carbon present in wood and fossil fuels (coal, oil, natural gas) is returned to the atmosphere by the process of combustion (burning) 4. The carbon-silicate cycle (which occurs on a geological timescale involving millions of years) returns CO2 to the atmosphere through volcanic eruptions and both chemical and physical weathering processes B. The nitrogen cycle i. The global circulation of nitrogen between organisms and the abiotic environment is know as the nitrogen cycle 1. Atmospheric nitrogen (N2) is so stable that it must first be broken apart in a series of steps before it can combine with other elements to form biological molecules 2. Nitrogen is an essential part of proteins and nucleic acids (DNA) 3. The atmosphere is 78% nitrogen gas (N2) ii. Five steps of the nitrogen cycle 1. Nitrogen fixation a. Conversion of gaseous nitrogen (N2) to ammonia (NH3)

Chapter 4 b. Nitrogen-fixing bacteria (including cyanobacteria) fixes nitrogen in soil and aquatic environments (anaerobic process) c. Combustion, volcanic action, lightning discharges, and industrial processes also fix nitrogen 2. Nitrification a. Conversion of ammonia (NH3) or ammonioum (NH4+) to nitrate (NO3-) b. Soil bacteria perform nitrification in a two-step process (NH3 or NH4+ is converted to nitrite (NO2-) then to NO3-) c. Nitrifying bacteria is used in this process 3. Assimilation a. Plant roots absorb NO3-, NO3 or NO4+ and assimilate the nitrogen of these molecules into plant proteins and nucleic acids b. Animals assimilate nitrogen by consuming plant tissues (conversion of aminio acids to proteins) c. This step does not involve bacteria 4. Ammonification a. Conversion of biological nitrogen compounds into NH3 and NH4+ b. NH3 is released into the abiotic environment through the decomposition of nitrogen-containing waste products such as urea and uric acid (birds), as well as the nitrogen compounds that occur in dead organisms c. Ammonifying bacteria is used in this process 5. Denitrification a. Reduction of NO3- to N2 b. Anaerobic denitrifying bacteria reverse the action of nitrogen-fixing and nitrifying bacteria C. The phosphorus cycle i. Phosphorus cycles from land to sediments in the ocean and back to land 1. Phosphorus erodes from rock as inorganic phosphates and plants absorb it from the soil 2. Animals obtain phosphorus from their diets, and decomposers release inorganic phosphate into the environment ii. Once in cells, phosphates are incorporated into biological molecules such as nucleic acids and ATP (adenosine triphosphate) iii. This cycle has no biologically important gaseous compounds D. The sulfur cycle i. Most sulfur is underground in sedimentary rocks and minerals or dissolved in the ocean ii. Sulfur gases enter the atmosphere from natural sources in both ocean and land

Chapter 4 1. Sea spray, forest fires and dust storms deliver sulfates (SO42-) into the air 2. Volcanoes release both hydrogen sulfide (H2S) and sulfur oxides (Sox) iii. A tiny fraction of global sulfur is present in living organisms 1. Sulfur is an essential component of proteins 2. Plant roots absorb SO42- and assimilate it by incorporating the sulfur into plant proteins 3. Animals assimilate sulfur when they consume plant proteins and covert them to animal proteins iv. Bacteria drive the sulfur cycle E. The hydrologic cycle i. The hydrologic cycle is the global circulation of water for the environment to living organisms and back to the environment 1. It provides a renewable supply of purified water for terrestrial organisms 2. the hydrologic cylce results in a balance between water in the ocean, on the land, and in the atmosphere ii. Water moves from the atmosphere to the land and ocean in the form of precipitation iii. Water enters the atmosphere by evaporation and transpiration iv. The volume of water entering the atmosphere each year is about 389,500 km3 II. Solar Radiation A. The sun powers biogeochemical cycles (i.e., hydrologic, carbon) and is the primary determinant of climate B. Most of our fuels (i.e., wood, oil, coal, and natural gas) represent solar energy captured by photosynthetic organisms C. Approximately one billionth of the total energy released by the sun strikes our atmosphere i. Clouds, snow, ice, and the ocean reflect about 31% of the solar radiation that falls on Earth ii. Albedo is the proportional reflectance of solar energy from the Earth’s surface 1. Glaciers and ice sheets have a high albedo and reflect 80 to 90% of the sunlight hitting their surfaces 2. Asphalt pavement and buildings have a low albedo (10 to 15%) 3. Forests have a low albedo (about 5%) iii. 69% of the solar radiation that falls on the Earth is absorbed and runs the hydrologic cycle, drives winds and ocean currents, powers photosynthesis, and warms the planet D. Temperature changes with latitude i. Near the equator, the sun’s rays hit vertically 1. Energy is more concentrated 2. Produces higher temperatures 3. Rays of light pass through a shallower envelope of air

Chapter 4 ii. Near the poles, the sun’s rays hit more obliquely 1. Energy is spread over a larger surface area (less concentrated) 2. Produces lower temperatures 3. Rays of light pass through a deeper envelope of air, causing the sun’s energy to scatter and reflect back to space E. Temperature changes with season i. Season’s are determined primarily by Earth’s inclination on its axis ii. March 21 to September 22 the Northern Hemisphere tilts toward the sun (spring/summer) iii. September 22 to March 21 the Northern Hemisphere tilts away from the sun (fall/winter) III. The Atmosphere A. The atmosphere is an invisible layer of gases that envelops Earth and protects it’s surface from lethal amounts of high energy radiation (i.e., UV rays, X rays and cosmic rays) i. 99% of dry air is composed of oxygen (21%) and nitrogen (78%) ii. Argon, carbon dioxide, neon, and helium make up the remaining 1% B. The interaction between atmosphere and solar energy is responsible for weather and climate C. Layers of the atmosphere vary in altitude and temperature with latitude and season i. Troposphere 1. Closest layer to Earth’s surface 2. Temperature decreases with increasing altitude 3. Extends to a height of approximately 10 km 4. Weather, including turbulent wind, storms, and most clouds occurs in the troposphere ii. Stratosphere 1. Temperature is more or less uniform, but does increase with increasing altitude 2. Extends from 10 to 45 km above Earth's surface 3. Steady wind, but no turbulence (commercial jets fly here) 4. Contains ozone layer iii. Mesosphere 1. Temperatures drop steadily (to lowest temperature in atmosphere) 2. Extends from 45 to 80 km above Earth's surface iv. Thermosphere 1. Very hot (nearly 1000˚C or more) 2. Extends from 80 to 500 km 3. Aurora borealis occurs in this level of the atmosphere v. Exosphere 1. The outermost layer of the atmosphere 2. Begins about 500 km above Earth's surface 3. The exosphere continues to thin until it converges with interplanetary space

Chapter 4 D. Differences in temperature caused by variations in the amount of solar energy reaching different locations on Earth drive the circulation of the atmosphere i. Air is heated by warm surfaces near the equator cause it to rise and expand ii. Due to subsequent chilling, air tends to sink to the surface at about 30 degrees north and south latitudes iii. Similar upward movements of warm air and its subsequent flow toward the poles occur at higher latitudes, farther from the equator iv. This continuous turnover moderates temperatures over Earth's surface E. Surface winds i. Horizontal movements resulting from differences in atmospheric pressure and from the Earth's rotation are called winds ii. Winds tend to blow from areas of high atmospheric pressure to areas of low pressure (greater difference = stronger winds) ii. The influence of Earth's rotation, which tends to turn fluids (air and water) toward the right in the Northern Hemisphere and toward the left in the Southern Hemisphere is called the Coriolis effect iv. The atmosphere has three prevailing winds 1. Polar easterlies blow from the northeast near the North Pole or from the southeast near the South Pole 2. Westerlies generally blow in the midlatitudes from the southwest in the Northern Hemisphere or the northwest in the Southern Hemisphere 3. Trade winds (tropical winds) generally blow from the northeast in the Northern Hemisphere or the southeast in the Southern Hemisphere IV. The Global Ocean A. The global ocean is a single, continuous body of salt water that covers nearly ¾ of the Earth's surface B. Geographers divide it into four sections separated by continents (Pacific, Atlantic, Indian, and Arctic oceans) C. Prevailing winds blowing over the ocean's surface and the position of land masses influence patterns of circulation i. Currents are mass movements of surface-ocean water ii. Gyres are large, circular ocean current systems that often encompass an entire ocean basin iii. The Coriolis effect also influences the paths of surface-ocean currents B. The varying density of seawater affects deep-ocean currents and creates a vertical mixing of ocean water i. The ocean conveyor belt moves cold, salty deep-sea water from higher to lower latitudes ii. The ocean conveyor belt affects regional and possibly global climate and shifts from one equilibrium state to another in a relatively short period (years to decades) C. Ocean interactions with the atmosphere are partly responsible for climate variability

Chapter 4 i. El Niño-Southern Oscillation (ENSO) is a periodic, large scale warming of surface waters of the tropical eastern Pacific Ocean that temporarily alters both ocean and atmospheric circulation patterns 1. Most ENSOs last 1 to 2 years 2. ENSO has a devastating effect on fisheries off South America and alters global air currents (causing severe and unusual weather worldwide) ii. La Niña occurs when the surface water temperature in the eastern Pacific Ocean becomes unusually cool, and westbound trade winds become unusually strong 1. La Nina often occurs after an ENSO 2. La Nina also affects weather patterns around the world, but its effects are more difficult to predict V. Weather and Climate A. Weather i. Weather refers to the conditions in the atmosphere at a given place and time ii. Weather includes temperature, atmospheric pressure, precipitation, cloudiness, humidity, and wind iii. Weather is continuously changing (hour to hour, day to day) B. Climate i. The average weather conditions that occur in a place over a period of years is termed climate ii. Climate is determined by temperature and precipitation iii. Other climate factors include wind, humidity, fog, cloud cover, and occasionally lightning C. Precipitation i. Precipitation refers to any form of water that falls from the atmosphere ii. Examples of precipitation include rain, snow sleet and hail iii. Precipitation has a profound effect on the distribution and kinds of organisms present D. Rain shadows, tornadoes and tropical cyclones (hurricanes/typhoons) are extreme forms of weather that can have a significant impact on regional climate VI. Internal Planetary Processes A. Plate tectonics i. Plate tectonics is the study of the dynamics of Earth’s lithosphere (outermost rigid rock layer) 1. The lithosphere is composed of seven large plates, plus a few smaller ones 2. The plates float on the asthenosphere (the region of the mantle where rocks become hot and soft) ii. Plate boundaries are typically sites of intense geologic activity – earthquakes and volcanoes are common in such a region B. Earthquakes

Chapter 4 i. Forces inside Earth sometimes push and stretch rocks in the lithosphere 1. The energy is released as seismic waves causing earthquakes 2. Most earthquakes occur along fault zones 3. More than 1 million earthquakes are recorded each year ii. Landslides and tsunamis are some of the side effects of earthquakes E. Volcanoes i. When one plate slides under or away from an adjacent plate, magma may rise to the surface, forming a volcano ii. Volcanoes occur at subduction zones, spreading centers, and above hot spots

Chapter 4

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Anthropogenic Changes to the Hydrologic Cycle

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: We need not be terribly concerned about human-caused changes to the hydrologic cycle, since most or all of these changes are local, occasional regional, and rarely global Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Chapter 4 Student See above Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Discuss human-caused changes to the hydrologic cycle.

Chapter 4

Instructor Notes for In-Class Activity 2 Title:

A Three Dimensional Look at the Planet

Time: Materials: Handouts:

10 – 25 minutes prep (practice); 15 – 25 minutes in class Large globe (inflatable is handy), flashlight None

Procedures:

Bring a large globe to class. Put Figures 5.13, 5.14 and 5.15 up (projector or overhead). Use the globe to describe the various land masses and ocean water flows depicted in these slides. Have students locate New York City, and follow the latitude across the Atlantic to Europe. What major European city is at the same latitude as New York City? What part of North America is at the same latitude as Oslo? Describe how prevailing winds crossing the Atlantic from East are warmed by ocean currents, thereby warming Europe. Next, describe how the El Nino and La Nina phenomena can have impacts in places thousands of miles apart.

Finally, use the flashlight to demonstrate the phenomena described in figure 5.8

Student Working in groups of 3-4, answer the following questions: Instructions: Note to instructor: Give the students the next two questions only after they have generated hypotheses.

Specific Suggestions:

Be sure to practice this first!

Remember to bring notes along.

Objectives:

• • •

Describe the influences of the oceans on climate.

Discuss the roles of solar energy and the Coriolis effect in producing global water flow patterns Define El-Nino Southern Oscillation and La Nina and describe some of their effects.

Chapter 4

Instructor Notes for In-Class Activity 3 Title:

Perturbing the carbon cycle

Time: Materials: Handouts:

5 minutes prep; 15 minutes in class Projection of Figure 5.2 None

Procedures:

Have students get together in groups of 3 -5 and discuss the topics below for 10 – 15 minutes. Then have them regroup and compare their answers.

Students will evaluate the long-term impacts of a quadrupling of carbon released through fossil fuel combustion, and the alternatives to that combustion.

Student Consider Figure 5.2. Assume that currently, most of the 6 x 1015 of Instructions: carbon released through combustion is produced by the energy demand of only 1/3 of the 6 billion people now on the planet. Consider a time in the next century when the population is 10 billion, and 2/3 of the population want energy at current demand levels.

1. If all of this comes from fossil fuel combustion, how much more carbon will be released to the atmosphere?

2. What changes would have to take place elsewhere in the carbon cycle 3. Are there any ways that humans could intervene elsewhere in the carbon cycle to accommodate this production? If so, how, and how difficult do you think it would be?

4. In the IPAT model, if P and A (here, energy use) both go up as described above, what changes in T would be required to keep I constant? Do you think these changes are feasible? Why or why not?

Specific Suggestions:

None

Objectives:

Describe the carbon cycle, and human impacts on the carbon cycle.

Chapter 4

Instructor Notes for In-Class Activity 4 Title:

The Cycling of Materials within Ecosystems

Time:

40 – 60 minutes prep: 60 minutes in class(or can assign research between class periods) 100 piece or less puzzle (kids puzzle), paint, varnish or laminate if desired 1 copy of each of the cycles. See below Activity 5 for handouts.

Materials: Handouts: Procedures:

1. Divide the students into equal groups, give each group a cycle: carbon, nitrogen, phosphorus, sulfur and hydrologic. Give them the corresponding handout of the figure that represents their group.

2. Have them put the puzzle together and paint over the picture part of the puzzle. You can assign the different color for each group or they can choose a color but each cycle will be a different color.

For example the carbon cycle is yellow, nitrogen cycle blue, etc.

Set the puzzles out to dry…

3. After the puzzles are dry have the students paste pictures of their Cycle on the puzzle. Each will be similar but different according to the cycle.

4. Use laminate or a sealant to seal the pictures to the puzzle.

Student After each group has finished making their puzzle, exchange puzzles Instructions: with the other groups and have them put the puzzles together. While they are putting the puzzles together they are reviewing the differences between the cycles and also the components in them.

Specific Suggestions:

The teacher could make the puzzles as far as painting them, but have the students put the pictures of their cycle on them.

Objectives:

Discuss each cycle and why they are different from each other. Can the students identify the need for each cycle? How do they interrelate with each other?

Chapter 4

Instructor Notes for In-Class 5 Title:

Cycles of the Ecosystems

Time: Materials: Handouts:

10 minutes prep Copies of the Figures for each cycle 1 copy per group of one of the Cycles

Procedures:

1. Divide the class into equal groups 2. Let one student of the group pick from the stack of Figures (5.2-5.6) face down so they cannot choose their cycle.

3. After the groups have their cycle explain to them they are the components of their cycle. They must come up with a community flag, set of rules or procedures on how they will have an impact on the ecosystem. What are their components? Do they have a mascot?

Cheer? Fight Song? Etc. 4. During the weeks of this chapter have the students present their cycle to the class. Let them be creative…..

Student Students are to research their cycle: nitrogen, carbon, sulfur, phosphorus Instructions: etc. They will present their cycle with a flag, mascot, fight song or other creative way. In defining their cycle, they must describe the cycle, its impact on the ecosystem and how does it make it different to the other cycles.

Specific Suggestions: Objectives:

Make the teams equal and promote creativity.

• • • •

Describe the influences the components of each cycle.

Discuss the roles of each cycle on the ecosystem.

Compare and contrast each cycle and its impact to the environment List the differences in each cycle.

Chapter 4

Chapter 4

Chapter 4

Chapter 4

Chapter 4

Chapter 4

Answers to Critical Thinking and Review End of Chapter Questions: 1. Briefly describe some of the long-term ecological research conducted at Hubbard Brook Experimental Forest (HBEF). What are some of the environmental effects observed in the deforestation study at HBEF? Ans: HBEF has conducted long-term studies that have addressed hydrology, biology, geology, and chemistry of forests and associated aquatic life. The effects of deforestation have also been studied. Deforestation studies have shown that there is an increase in soil erosion and leaching of essential minerals which results in decreased soil fertility.

2. What is a biogeochemical cycle? Why is the cycling of matter essential to the continuance of life?

Ans: Biogeochemical cycles move matter from one organism to another and from living organisms to the abiotic environment and back again. The cycles of matter- carbon, nitrogen, phosphorus, sulfur and hydrologic- involve biological, geologic and chemical interactions. These five cycles are particularly important to organisms, because these materials make up the chemical compounds of cells.

3. Describe how organisms participate in each of these biogeochemical cycles: carbon, nitrogen, phosphorus, and sulfur.

Ans: In the carbon cycle organisms fix, or incorporate, carbon from the atmosphere into chemical compounds through photosynthesis. Organisms also release carbon during cellular respiration. Other biological molecules that are not release during cellular respiration can be stored as fossil fuels for millions of years. Aquatic organisms incorporate Ca2+ and HCO3- into their shells. When these organisms die, their shells sink to the ocean floor and become part of the sedimentary rock layer. The CO2 in these rock layers will later be released due to weathering or subduction.

Atmospheric nitrogen is very stable and must be broken apart in order to combine with other elements. Bacteria are exclusively involved in all five steps of the nitrogen cycle, except assimilation. Nitrogen-fixing bacteria carry out biological nitrogen fixation in soil and aquatic environments. Soil bacteria perform nitrification, a two step process. First soil bacteria convert ammonia or ammonia to nitrite. Then other soil bacteria oxidize nitrite to nitrate. The process of nitrification furnishes these bacteria with energy.

Ammonification begins when organisms produce nitrogen-containing waste products such as urea and uric acid. These substances, as well as the nitrogen compounds that occur in dead organisms, are decomposed, releasing nitrogen into the abiotic environment. Finally, denitrifying bacteria reverse the action of nitrogen-fixing and nitrifying bacteria by returning nitrogen to the atmosphere.

In the phosphorus cycle, plants roots absorb inorganic phosphates. Animals obtain most of their required phosphate from the foods they eat. Phosphorus is then released back into the soil when organisms die and decompose. In aquatic environments, phosphorus is

Chapter 4 absorbed and assimilated by algae and plants, which are then consumed by plankton and larger organisms. A small portion of phosphate in the aquatic food web finds its way back to the land in the manure of sea birds.

A tiny fraction of the global sulfur is present in living organisms. Plant roots absorb sulfate and assimilate it by incorporating the sulfur into plant proteins. Animals assimilate sulfur when they consume plant proteins and convert it to animal proteins.

Sulfur is returned to the atmosphere by bacteria which converts sulfates to hydrogen sulfide gas.

4. What is the basic flow path of the nitrogen cycle?

Ans: There are five steps to the nitrogen cycle, in which nitrogen cycles between the abiotic environment and organisms: nitrogen fixation, nitrification, assimilation, ammonification and denitrification. Bacteria are exclusively involved in all of these steps except assimilation.

5. A geologist or physical geographer would describe the phosphorus cycle as a “sedimentary pathway.” Based on what you have learned about the phosphorus cycle in this chapter, what do you think that means?

Ans: Phosphorus does not form compounds in the gaseous phase and does not appreciably enter the atmosphere. In the phosphorus cycle, phosphorus cycles from the land to sediments in the ocean and back to the land. Phosphorus in plants comes from weathered sedimentary rock layers and returns to the ocean floor to be incorporated back into rock.

6. Explain why Earth’s temperature changes with latitude and with the seasons.

Ans: Temperature changes with Latitude On average the sun’s rays hit vertically near the equator, making the energy more concentrated and producing higher temperatures. At higher latitudes, the sun’s rays hit more obliquely, making the sun’s energy to be scattered and the temperatures are lower.

Temperature with seasons Seasons are determined primarily by Earth’s inclination on its axis. During half of the year the Northern Hemisphere tilts toward the sun and the temperature is warmer. During the other half it tilts away and the temperature is colder. The orientation in the Southern Hemisphere is the opposite of the Northern.

7. What are the two lower layers of the atmosphere? Cite at least two differences between them.

Ans: The layer of the atmosphere closest to the Earth is the troposphere. The troposphere extends to a height of approximately 10km (6.2mi). The temperature of the troposphere decreases with increasing altitude about -6°C (-11oF) for every kilometer. Weather,

Chapter 4 including turbulent wind, storms and most clouds, occur in the troposphere. The layer directly above the troposphere is the stratosphere. The stratosphere extends from 10-45 km (6.2 to 28 mi) above the Earth’s surface and contains the ozone critical to life because it absorbs much of the sun’s damaging ultraviolet radiation. There is a steady wind but no turbulence. There is little water, and temperature is more or less uniform (-45°C to 75°C), however, the absorption of ultraviolet radiation by the ozone layer heats the air, and so temperature increases with increasing altitude in the stratosphere.

8. Describe the general directions of atmospheric circulation.

Ans: Differences in temperature are caused by variations in the amount of solar energy reaching different locations on Earth, and drive the circulation of the atmosphere. The warm surface near the equator heats the air in contact with it, causing this air to expand and rise. As the warm air rises, it cools and then sinks again. Much of it re-circulates almost immediately to the same areas it has left, but the remainder of the heated air splits and flows in two directions, toward the poles. The air chills enough to sink to the surface at about 30 degrees north and south latitudes. This descending air splits and flows over the surface in two directions. Similar upward movements of warm air and its subsequent flow toward the poles occur at higher latitudes, farther from the equator. At the poles, the cold polar air sinks and flows toward the lower latitudes, generally beneath the sheets of warm air that simultaneously flow toward the poles. The constant motion of air transfers heat from the equator toward the poles, and as the air returns, it cools the land over which it passes. This continuous turnover moderates temperatures over Earth’s surface.

9. What is a gyre, and how are gyres produced?

Ans: Gyres are large, circular ocean current systems that often encompass an entire ocean basin. Gyres are produced by persistent prevailing winds that blow over the oceans.

10. How does ENSO affect climate on land?

Ans: ENSO are periodic, large-scale warming of surface waters of the tropical eastern Pacific Ocean that affects both ocean and atmospheric circulation patterns. The heat from the ocean can affect atmospheric circulation. ENSO alters global air currents that can result in sometimes dangerous weather.

11. What are some of the environmental factors that produce areas of precipitation extremes, such as rain forests and deserts?

Ans: Answers will vary but should include: rain shadow and Hadley cells 12. The system encompassing Earth’s global mean surface temperature can be diagrammed as follows:

Chapter 4

Explain each part of this system.

Ans: The sun releases energy into space in the form of electromagnetic radiation. A small fraction of this energy reaches the Earth’s surface and is absorbed and runs the hydrologic cycle, drives winds and ocean currents, powers photosynthesis and warms the plant. The amount of energy absorbed is affected by albedo. Albedo is the proportional reflectance of solar energy from Earth’s surface, commonly expressed as a percentage.

Glaciers and ice sheets have high albedo, whereas ocean and forests have low albedo.

The more energy that is absorbed the greater the Earth’s global mean temperature will be.

Aerosols are tiny particles of air pollution consisting mostly of sulfates, nitrates, carbon, mineral dusts, and smokestack ash. Once in the atmosphere, aerosols enhance the scattering and absorption of sunlight in the atmosphere and cause brighter clouds to form.

Both the clouds and the light-scattering effect in the atmosphere cause a warming of the atmosphere and a threefold reduction in the amount of solar radiation reaching Earth's surface, including the ocean. Ultimately, all of this energy is lost by the continual radiation of long-wave infrared energy into space.

13. How are tornadoes and tropical cyclones alike? How do they differ?

Ans: A tornado is a powerful, rotating funnel of air associated with severe thunderstorms.

Tornadoes form when a mass of cool, dry air collides with warm, humid air, producing a strong up-draft of spinning air. Tropical cyclones are giant, rotating tropical storms with winds of at least 118 km per hour. Tropical cyclones form as strong winds pick up moisture over warm surface waters of the tropical ocean and starts to spin as a result of the Earth’s rotation.

14. Relate the locations of earthquakes and volcanoes to plate tectonics.

Ans: Most earthquakes occur along faults, fractures where rock moves forward and backward, up and down, or from side to side. Fault zones are often found at plate boundaries- any area where two plates meet. Therefore, earthquakes are very common at plate boundaries. Understanding plate tectonics has increased our knowledge of earthquakes and predicting where they may occur.

Chapter 4 15. Examine the following changes that have been identified in the arctic hydrologic system in the past few decades. Predict the effect of these changes on the salinity in the North Atlantic Ocean.

Ans: Due to increased precipitation, melting of artic glaciers, and decreasing extent and thickness of artic sea ice the salinity in the North Atlantic Ocean is likely to decrease.

Cold, salty warm is less dense than warm, less salty water. This physical property drives the deep ocean conveyor. Scientists are therefore concerned that this decrease in salinity could alter the ocean conveyor and the global climate.

16. How have global air temperatures changed in the recent past? How is this change related to the carbon cycle?

Ans: Globally average air temperatures have increased during the past century. The increase in air temperature has been accompanied by a corresponding increase in atmospheric carbon dioxide. As humans demand for fossil fuels increase the amount of carbon dioxide being released into the atmosphere has also increased.

Answers to Review Questions The Cycling of Materials Within Ecosystems 1. What roles do photosynthesis, cellular respiration, and combustion play in the carbon cycle?

The global movement of carbon between organisms and the abiotic environment is known as the carbon cycle. Photosynthesis incorporates carbon from the abiotic environment into the biological compounds of producers. Those compounds are then used as fuel for cellular respiration, and as a result, CO2 is returned to the atmosphere. Similarly, carbon is also returned to the atmosphere through combustion (i.e., burning of coal, oil, natural gas, or wood).

2. What are the five steps of the nitrogen cycle?

The five steps of the nitrogen cycle are nitrogen fixation, nitrification, assimilation, ammonification, and denitrification.

3. How does the phosphorus cycle differ from the carbon, nitrogen, and sulfur cycles?

Chapter 4 Unlike the carbon, nitrogen, and sulfur cycles, phosphorus does not form compounds in the gaseous phase and does not appreciably enter the atmosphere (except during dust storms).

4. What sulfur-containing gases are found in the atmosphere?

While sulfur gases comprise only a minor part of the atmosphere, they are released by many different processes. For example, sea sprays, forest fires, and dust storms deliver sulfates (SO2-4) into the air. Additionally, volcanoes release both hydrogen sulfide (H2S) and sulfur oxides (SOx) into the atmosphere.

Solar Radiation 1. How does the sun affect temperature at different latitudes? Why?

Variation in Earth’s temperature is produced because the sun’s energy does not reach all places uniformly. More specifically, the angle at which the sun’s rays strike Earth varies from one geographic location to another owing to Earth’s spherical shape and its inclination on its axis. On average, the sun’s rays hit vertically near the equator, making the energy more concentrated and producing higher temperatures. At higher latitudes, the sun’s rays hit more obliquely. This results in the energy being spread over a larger surface area. Additionally, rays of light entering the atmosphere obliquely near the poles pass through a deeper envelope of air than does light entering near the equator. This causes more of the sun’s energy to be scattered and reflected back to space, and lessens the concentration of solar energy reaching polar areas; thus, creating lower temperatures near the poles.

2. What is albedo?

Albedo is the proportional reflectance of solar energy from Earth’s surface. It is commonly expressed as a percentage. Glaciers and ice sheets tend to have high albedos, while oceans and forests exhibit low albedos.

The Atmosphere 1. What is the innermost layer of the atmosphere? Which layer of the atmosphere contains the ozone that absorbs much of the sun’s ultraviolet radiation?

The innermost layer of the Earth’s atmosphere is the troposphere. The stratosphere, found directly above the troposphere, contains a layer of ozone that absorbs much of the sun’s damaging ultraviolet radiation.

2. What basic forces determine the circulation of the atmosphere?

Variations in the amount of solar energy reaching different places on Earth largely drive atmospheric circulation. Likewise, atmospheric heat transfer from the equator to the poles produces a movement of warm air toward the poles and a movement of cool air toward the equator, moderating the climate. The

Chapter 4 atmosphere also exhibits surface winds, complex horizontal movements that result in part from differences in atmospheric pressure and from the Coriolis effect.

The Global Ocean 1. How are the sun’s energy, prevailing winds, and surface-ocean currents related?

The heat from solar energy is partly responsible for the major surface winds that blow continually across the Earth; it is these persistent prevailing winds, which blow over the ocean and produce surface-ocean water currents.

2. What is the El Niño-Southern Oscillation (ENSO)? What are some of its global effects?

The El Niño-Southern Oscillation (ENSO) is a periodic, large-scale warming of surface water of the tropical eastern Pacific Ocean that affects both ocean and atmospheric circulation patterns. Globally, ENSO is often correlated with fishery devastation due to the lack of upwellings of colder, nutrient rich deep water during an ENSO event. ENSO also alters global air currents, directing unusual and sometimes dangerous weather to areas far from the tropical Pacific. It has been associated with torrential rains, snows, ice storms, floods, fires and droughts in parts of the world unprepared for such weather events.

Weather and Climate 1. How do you distinguish between weather and climate? What are the two most important climate factors?

Weather refers to the conditions in the atmosphere at a given place and time, whereas climate refers to the average weather conditions that occur in a place over a period of years. Temperature and precipitation largely determine an area’s climate.

2. Distinguish between tornadoes and tropical cyclones.

A tornado is a powerful, rotating funnel of air associated with severe thunderstorms. Tornados form when a mass of cool, dry air collides with warm, humid air, producing a strong updraft of spinning air on the underside of a cloud.

When this funnel makes contact with the ground it is considered a tornado. A tropical cyclone is a giant, rotating tropical storm with high winds. Tropical cyclones forms as strong winds pick up moisture over warm surface waters of the tropical ocean and start to spin as the result of Earth’s rotation. Tropical cyclones are called hurricanes in the Atlantic, typhoons in the Pacific, and cyclones in the Indian Ocean.

Internal Planetary Processes 1. What are tectonic plates and plate boundaries?

Chapter 4 Plate tectonics is the study of the processes by which the lithospheric plates move over the asthenosphere. Earth’s lithosphere (outermost rock layer) consists of seven large plates and a few smaller ones. Any area where two plates meet is termed a plate boundary. Plate boundaries are sites of intense geologic activity, such as mountain building, volcanoes, and earthquakes.

2. Where are earthquakes and volcanoes commonly located, and why?

Earthquakes and volcanoes are commonly located along plate boundaries due to the events that occur when plates meet. Three types of plate boundaries exist: divergent plate boundaries (when two plates move apart); convergent plate boundaries (when two plates collide); and transform plate boundaries (when plates move horizontally in opposite but parallel directions.

Chapter 5 Ecosystems and Living Organisms Lecture Outline: I. Evolution: How Populations Change Over Time A. Natural selection i. Darwin proposed the theory of evolution by natural selection in 1859 ii. Natural selection is the process in which better-adapted individuals – those with a combination of genetic traits better suited to environmental conditions – are more likely to survive and reproduce, increasing their proportion in the population 1. An evolutionary modification that improves the chances of survival and reproductive success of the population in its environment is referred to as an adaptation 2. Evolution by natural selection consists of four observations about the natural world a. Overproduction b. Variation c. Limits on population growth d. Differential reproductive success iii. Evolution is defined as the cumulative genetic changes that occur over time in a population of organisms 1. A vast body of evidence supports evolution a. Observations from the fossil record b. Comparative anatomy c. Biogeography d. Molecular biology 2. The modern synthesis, postulated in the late 1930s/early 1940s combined the principles of genetics with Darwin’s theory of natural selection; it explains Darwin’s observation of variation among offspring in terms of mutation B. Evolution of biological diversity: the domains and kingdoms of life i. Biologists use a three domain/six kingdom system of classification to arrange living organisms ii. Prokaryotic organisms fall into two domains/kingdoms 1. Domain Archaea: Kingdom Archaea - frequently live in oxygendeficient environments; often adapted to harsh conditions (hot springs, salt ponds, hydrothermal vents in ocean floor) 2. Domain Bacteria: Kingdom Bacteria – all other prokaryotes – thousands of species; most are decomposers, some are parasites; some cause disease; some are photosynthetic; important in biogeochemical cycles iii. Eukaryotic organisms fall into one domain/four kingdoms 1. Domain Eukarya

Chapter 5 a. Kingdom Protista – unicellular or relatively simple multicellular organisms, (i.e., algae, protozoa, slime molds, and water molds); important in aquatic food chains; algae are important producers b. Kingdom Plantae – complex multicellular, most use radiant energy to manufacture food molecules by photosynthesis; play important role as producers and source of atmospheric oxygen c. Kingdom Fungi – most are complex multicellular, secrete digestive enzymes into their food and then absorb the predigested nutrients; decomposers; some are parasites; some cause disease d. Kingdom Animalia – complex multicellular, ingest their food and then digest it inside their bodies; consumers-herbivores, carnivores, omnivores, and detritivores II. Biological Communities A. A biological community and its abiotc environment comprise an ecosystem i. A community is an association of different populations of organisms that live and interact in the same place at the same time ii. Unraveling of the many positive and negative, direct and indirect interactions of organisms living as a community is one of the goals of community ecologists B. Succession: how communities change over time i. Succession is the process of community development over time, in which species in one stage are replaced by different species ii. Primary succession occurs when the change is species composition over time takes place in a previously uninhabited environment 1. Recently formed volcanic lava and rock scraped clean by glaciers represent previously uninhabited environments 2. The initial community that develops during primary succession is termed a pioneer community 3. Primary succession takes hundreds or thousands of years to occur iii. Secondary succession begins in an environment following destruction of all or part of an earlier community 1. Abandoned farmland and open areas caused by forest fires are common examples of secondary succession sites 2. Each stage of succession supports its own characteristic animal life III. Interactions Among Organisms A. Symbiosis defines any intimate relationship or association between members of two or more species i. The partners of a symbiotic relationship are termed symbionts ii. Thousands, even millions, of symbiotic associations that result from coevolution fall into three categories 1. Mutualism - both partners benefit (+,+) 2. Commensalism – one organism benefits and the other one is neither harmed nor helped (+,0)

Chapter 5 3. Parasitism – one organism benefits and the other is adversely affected (+,-) a. When a parasite causes disease and/or death of a host, it is known as a pathogen b. Parasitism is a successful lifestyle; more than 100 parasites live in or on the human species alone B. Predation is defined as the consumption of one species (the prey) by another (the predator) i. Includes both herbivore-carnivore interactions and producer-herbivore interactions ii. Predation has resulted in an evolutionary “arms race” with the coevolution of predator and prey strategies 1. Pursuit and ambush 2. Plant defenses against herbivores 3. Defensive adaptations of animals C. Competition occurs when two or more individuals attempt to use an essential common resource such as food, water, shelter, living space, or sunlight i. Intraspecific competition occurs among individuals within a population ii. Interspecific competition occurs between species IV. The Ecological Niche A. The ecological niche is defined as the totality of an organisms adaptations, its use of resources, and the lifestyle to which it is fitted i. An ecological niche is basically determined by all a species’ structural, physiological, and behavioral adaptations ii. It includes the local environment in which an organism lives, its habitat, as well as the abiotic components of its environment (i.e., light, temperature, moisture) 1. The potential, idealized ecological niche of an organism is its fundamental niche 2. The lifestyle an organism actually pursues and the resources it actually uses make up its realized niche B. Limiting resources i. Any resource at a suboptimal level relative to an organism’s need for it or at a level in excess of an organism’s tolerance for it is a limiting resource ii. Limiting resources restrict the ecological niche of an organism, and often affect only one part of an organism’s life cycle C. Competitive exclusion and resource partitioning i. The idea of competitive exclusion holds that no two species indefinitely occupy the same niche in the same community due to competition between species; however, coexistence can occur if the overlap in the two species niches is reduced ii. Competition has an adverse effect on all species that use a limited resource iii. In resource partitioning, coexisting species’ niches differ from each other in one or more ways (i.e., timing and/or location of feeding, nest sites, etc.)

V. Keystone Species

Chapter 5 A. A keystone species is a species, often a predator, that exerts a profound influence on a community in excess of that expected by it s relative abundance B. Keystone species are vital in determining the nature and structure of the entire ecosystem VI. Species Richness A. Species richness is defined as the number of species in a community B. Important factors determining species richness include: the abundance of potential ecological niches, closeness to the margins of adjacent communities, geographic isolation, dominance of one species over others, habitat stress, and geologic history i. Species richness is usually greater at the margins of adjacent communities than in the centers 1. Species richness is usually greater at the margins of adjacent communities than in their centers a. An ecotone is the transitional zone where two or more communities meet b. Ecotones contain all or most of the ecological niches of the adjacent communities as well as some niches unique to the ecotone 2. The change in species composition produced at ecotones is known as the edge effect ii. Species richness is inversely related to the environmental stress of a habitat iii. Species richness, ecosystem services, and community stability 1. Conservationists maintain that ecosystems with greater species richness better supply ecosystem services than ecosystems with lower species richness 2. Ecosystem services are important environmental benefits that ecosystems provide to people (i.e., clean air, water and fertile soil) 3. Community stability, the ability of a community to withstand environmental disturbances, is also thought to directly correlate with community complexity

Chapter 5

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Producer, Consumer…Predator, Prey

Time: Materials: Handouts:

5 minutes prep; 20 – 30 minutes in class None Enough copies of each handout for everyone in the class.

Procedures:

Divide class into 3, 6, 9 etc. groups of two to five people. Have them organize into clusters of three groups; for each cluster, assign one group to be producers, one to be the consumers/prey, and one to be predators.

Each group will read its group’s description.

Next, each group will make one small change to its description: 1. The producer group should make a small change that helps it avoid the consumer.

2. The consumer will make one small change to EITHER better get the producer or better avoid the predator.

3. The predator will make one small change to better catch the prey The groups should then reveal their changes, and discuss how this impacts each of the three.

Repeat this process at least three times, each time reacting to the new situation.

Then have all the groups describe the “new” plants / creatures they have found, paying attention to a) how different they have become over time and b) how different the driving forces were.

Student You will be assigned as a producer, consumer/prey or predator in a Instructions: simple ecosystem. You will then have the opportunity to make one small change that improves your chances vis a vis whatever eats you and or is eaten by you. At the same time, the other creatures/plant will be changing. You will repeat this several times, and at the end will compare your “evolved” plant / creature to the original, as well as to groups “evolving” in parallel to yours. Note that you need not only make “reactive” changes; you may also make more “cooperative” changes.

Specific Suggestions:

None

Objectives:

• • •

Describe producer, consumer, predator and prey relationships Describe the process of natural selection.

Define production, consumption and predation

Chapter 5 In-Class Activity 1: Handout Original animal descriptions Producer. You are a small plant that grows in some shade. You grow quickly into a small, stocky shape, and have some short spines to limit the extent to which your consumer can eat you.

Consumer/Prey You have a short snout that means that you can eat part of the producer, but cannot eat too deeply into the delicious fleshy part because you get poked by the spikes. You can run short distances quickly into a small hole to avoid the predator; you curl into a hard-to-see ball if it gets too close.

Predator You catch the prey by sneaking up quickly. You only see it well when it is moving. When it runs, you need to catch it fast; you are too small to get into its lair, and it is a quick escape artist.

Chapter 5

Instructor Notes for In-Class Activity 2 Title:

Designing a Closed Aquarium

Time: Materials: Handouts:

5 minutes prep; 20 – 30 minutes in class None None

Procedures:

None

Student Normally, when people design aquaria, they expect to provide a variety Instructions: of inputs. These include energy (food), air (bubblers), temperature and chemical control, and occasional cleaning. It is possible, however, to design a “closed” aquarium, provided that it has an external source of light.

• Working in groups of 3-4, draw and describe a simple “closed” aquarium. This will require at minimum a producer and a decomposer, but that would be rather boring. Include at least one primary consumer. Explain what role each organism will perform.

• What do you think will be the biggest threat to the system’s stability?

• If you were to get the system to work for a year, do you think it will change over time?

• Why and in what way?

Choose one member of you group to report back to the class. Discuss how your group’s aquarium differs from that of another group.

Finally, get back together with your group and discuss whether you can improve your design.

Specific Suggestions:

None

Objectives:

Describe how producers, consumers and decomposers interact in a closed system.

Chapter 5

Instructor Notes for In-Class Activity 3 Title:

Exploring Niches on Campus

Time: Materials: Handouts:

0 – 30 minutes prep; Full class period.

None None

Procedures:

Most campuses harbor any number of species. A few of these may have been in place before the campus opened. Most, however, have either moved in or have adapted substantially to the campus setting.

First, have students develop lists of aspects of niches.

Next, have them tour your campus (or other suitable location), looking for animals and plants that live there. Have students take notes on the niches of one or more of these animals. Pay particular attention to 1. Living space 2. Predators (if any…look up, you may find birds of prey!). Sources of protection from prey 3. Sources of food Return to class and compare notes. Discuss: How have animals adapted to life on campus?

How similar / different do you think species interactions are to / from conditions before the campus was opened?

Student First, create a list of items or conditions associated with an organism’s Instructions: niche.

Next, explore your campus, looking for plants and animals that live there (these may or may not be intentionally maintained). Take notes on the niches of these plants or animals Return to class, and discuss how animals have adapted to these niches. In what ways are they similar to or different from “natural” settings?

Specific Suggestions:

None

Objectives:

Describe the factors that contribute to an organism’s ecological niche.

Chapter 5

Instructor Notes for In-Class Activity 3 Title:

Humans in Ecological Relationships

Time: Materials: Handouts:

5 minutes prep; 15 – 25 minutes in class.

None None

Procedures:

Have students describe, in ecological terms, our relationships with each of the following: • Potatoes • Aphids • Weeds • Shade Trees • Cockroaches • Lawns • Honeybees • Beef cattle • Dairy cattle Use this as a springboard to discuss ecological relationships, and the challenges are advantages to thinking about human-environment relationships in ecological terms.

Student Describe, using ecological terminology, human relationships with each of Instructions: the following: • Potatoes • Aphids • Weeds • Shade Trees • Cockroaches • Lawns • Honeybees • Beef cattle • Dairy cattle Which of these fit cleanly into one of the categories typically used by ecologists?

Specific Suggestions: Objectives:

What are the implications of this for “sustainability” None • •

Explain ecological terms for interactions among organisms Describe interactions among humans and other organisms in ecological terms

Chapter 5

Instructor Notes for In-Class Activity 4 Title:

Succession

Time:

5 minutes prep; 60 minutes out of class time and 5 minute per group presentation time None None

Materials: Handouts: Procedures:

Dive the students into teams and have them search the internet for “Succession Pictures”. Each team should come up with at least three different succession pictures. Have them put them into a power point presentation and present to the class.

Student As a team you are to surf the internet and look for three different types Instructions: of “Succession Pictures”. Put them in a power point presentation and make sure you reference them and title them according to the succession.

A minimum of 10 slides per power point.

Optional activity Suggestion:

Instead of a power point presentation all the pictures can be brought to the class and a calendar for a year can be made with the pictures. If some students brought in winter type pictures they could be used for the winter months etc. This calendar could be displayed throughout the year using the succession pictures.

Objectives:

• •

Explain the process of succession as it deals with the environment.

Describe the process of succession and how communities change over time.

Chapter 5

Answers to Critical Thinking and Review End of Chapter Questions: 1. Charles Darwin once said, “It is not the strongest of the species that survive, nor the most intelligent, but the ones most responsive to change.” How does this statement relate to the definition of evolution?

Ans: Natural selection is the mechanism of evolution. Organisms that are the most fit are the most likely to survive to the age of reproduction and pass those advantages traits on to their off springs. Fittest does not necessarily mean the strongest or the most intelligent but instead the traits that give the best advantage for survival in a particular environment.

2. During mating season, male giraffes slam their necks together in fighting bouts to determine which male is stronger and can mate with females. Explain how long necks may have evolved under this scenario, using Darwin's theory of evolution by natural selection.

Ans: Darwin recognized that, from one generation to the next, inherited traits favorable to survival in a given environment would be preserved, whereas unfavorable ones would be eliminated. The result would be adaptation, evolutionary modification that improves the chances of survival and reproductive success of the population in its environment. If male giraffes with long necks gained more mates they would leave more offspring, thereby, increasing the number of long necked giraffes in the population.

3. How do the three domains relate to the six kingdoms of classification?

Ans: Prokaryotes are organisms that lack membrane bound organelles, including a nucleus.

Prokaryotes are classified into two domains, Archaea and Bacteria. Archaea are normally found in oxygen-deficient environments and are often adapted to harsh environments. The remaining prokaryotes are classified as Bacteria. Eukaryotes are organisms that have membrane bound organelles and a nucleus surrounded by a nuclear membrane. Eukaryotes are classified in the domain Eukarya and include the kingdoms Protista, Fungi, Plantae, and Animalia.

4. How are the following factors related in determining the growth rate: birth rate, death rate, immigration, and emigration?

Ans: Birth rates and immigration results in an increase in the growth rate. Death rate and emigration cause a reduction in the growth rate. If the Birth rate and immigration is equal to the death rate and emigration there will be a net zero change in the growth rate. If the Birth rate and immigration is greater than the death rate and emigration the growth rate will be positive. If the birth rate and immigration is less than the death rate and emigration the growth rate will be negative.

5. Draw a graph to represent the long-term growth of a population of bacteria cultured in a test tube containing a nutrient medium that is replenished. Now draw a graph to represent the growth in a test tube when the nutrient medium is not replenished. Explain the difference.

Chapter 5 Ans: Bacteria that are grown in a test tube in which the nutrient medium is replenished will enter a stable or carrying capacity stage of a population growth cycle. Since the medium is being replaced there will be available nutrients for the bacteria to consume and toxic by-products will be removed when the nutrient media is replenished. Bacteria growing in a test tube in which the nutrient medium is not replaced will enter into a death phase as the supply of nutrients is depleted and toxic wastes accumulate.

6. Which of the following are density-dependent factors, and why: a hurricane, disease, and competition?

Ans: Density dependent factors are any environmental factor whose effect on a population changes as its population density changes.

I. Hurricane – is not a density dependent factor since the effect of a hurricane on a population does not change based on the population size. A hurricane is a densityindependent factor.

II. Disease – is a density dependent factor since the occurrence of a disease within a population normally increases as the population grows dues to stress and the members of a population encountering each other more frequently and the chance of transmitting an infectious disease more likely.

III. Competition- is a density dependent factor. As population size increases competition for resources also increase.

7. How do survivorship curves relate to r selection and K selection in animals.

Ans: Populations described as r selection have traits that contribute to a high population growth rate. Small body size, early maturity, short life spans, large broods, and little or no parental care is typical of r strategies. K selection maximizes the chance of surviving in an environment where the number of individuals is near the carrying capacity. K selected species do not produce large numbers of offsprings, they have late reproduction, long life spans, low reproductive rates, and invest a lot of resources into parental care.

8. What is the difference between a source habitat and a sink habitat in terms of birth rates and death rates?

Ans: A source habitat is any habitat that increases the likelihood of survival and reproductive success for an individual living there. A sink habitat is a lower quality habitat where the local birth rate is less than the local death rate. Without immigration from other areas a sink population will decline and become extinct.

9. What is an organism’s ecological niche, and why is a realized niche usually narrower, or more restricted, than a fundamental niche?

Ans: The potential, idealized ecological niche of an organism is its fundamental niche. Various factors such as competition with other species usually exclude it from part of its fundamental niche. The lifestyle an organism actually pursues, and the resources it actually uses, make up its

Chapter 5 realized niche. Put differently, an organism is potentially capable of using much more of its environment's resources or of living in a wider assortment of habitats than it actually does.

10. What portion of the human's fundamental niche are we occupying today? Do you think our realized niche has changed over the past 200 years? Why or why not?

Ans: Answers will vary 11. What is the most likely limiting resource for plants and animals in deserts? How are limiting resources related to competition? Explain your answer.

Ans: Most limiting resources that scientists have investigated are simple variables such as the mineral content of soil, extremes of temperature, and amount of precipitation. Such investigations have disclosed that any resource that exceeds an organism's tolerance or is present in quantities smaller than the minimum required limits the occurrence of that organism in an ecosystem. In a desert the limiting resource for most plants and animals is available water. Many plants and animals that live in the desert have developed adaptations to conserve water.

12. What type of symbiotic relationship—mutualism, commensalism, or predation—do you think exists between the pygmy seahorse and the gorgonian coral pictured in Figure 5.22?

Explain your answer.

Ans: The pygmy seahorse and the gorgonian coral live in a commensalism. A commensalism is a type of symbiosis in which one organism benefits and the other one is neither harmed nor helped.

13. How is predation related to the concept of energy flow through ecosystems (covered in Chapter 3)?

Ans: Predation transfers energy form a lower trophic level to a higher trophic level. Energy is transferred when animals eat other animals (for example, herbivore-carnivore interactions) and when animals eat plants (producer-herbivore interactions). The transfer of symbiotic relationships will vary depending on the nature of the relationship. In mutualism, energy may flow back and forth between the symbionts; in commensalism, no energy flow may take place, and in a parasitism energy is only flowing in one direction.

14. Some biologists think that protecting keystone species would help preserve biological diversity in an ecosystem. Explain.

Ans: Keystone species are vital in determining the nature and structure of the entire ecosystem— that is, its species composition and its ecosystem functioning. For this reason, identifying and protecting keystone species are crucial goals of conservation biologists because if a keystone species disappears from an ecosystem, many other organisms in that ecosystem may become more common, rare, or even disappear.

Chapter 5 15. Why does species richness vary from one community to another?

Ans: Species richness is the number of species in a community. Species richness is determined by several factors, including abundance of potential ecological niches, closeness to the margins of adjacent communities, geographic isolation, dominance of one species over others, habitat stress, and geologic history.

16. What kinds of ecosystem services does a forest provide?

Ans: Services provided by forests include: purify air and water; produce and maintain soil; absorb carbon dioxide; provide wildlife habitat; and provide humans with wood and recreation.

17. Describe an example of secondary succession. Begin your description with the specific disturbance that preceded it.

Ans: Answers will vary. Disturbance may be a fire or abandoned farmland. Secondary succession on abandoned farmland in the southeastern United States proceeds in this sequence: crabgrass → horseweed → broomsedge and other weeds → pine trees → hardwood trees.

18. Draw a diagram of three concentric circles and label the circles to show the relationships among species, ecosystems, and communities. If you were adding symbiosis, predation, and competition to the simple system you have depicted, in which circle(s) would you place them?

Ans: Answers will vary 19. Study the graph and determine the overall trend in biological diversity of vertebrate species from 1970 to 2000. Sociobiologist E. O. Wilson says that the five forces responsible for this trend are habitat loss, invasive species, pollution, population growth, and overconsumption. Pick any two of these forces and relate them to energy use and/or climate change.

Chapter 5 Ans: The overall trend is a decrease in the number of species. Part two answers will vary.

Answers to Review Questions Evolution: How Populations Change Over Time 1. How do biologists define evolution?

Biologists define evolution as the cumulative genetic changes that occur over time in a population of organisms. Charles Darwin, a 19th century naturalist, proposed that the evolution of species resulted from the process of natural selection; a theory widely supported by the biologists today.

2. What are Darwin’s four premises of evolution by natural selection?

Evolution by natural selection consists of four observations about the natural world: (1) high reproductive capacity (i.e., each species produces more offspring than will survive to maturity); (2) inheritable variation (i.e., the individuals in a population exhibit inheritable variation in their traits); (3) limits on population growth (i.e., organisms compete with one another for the resources needed to survive); and (4) differential reproductive success (i.e., those individuals with the most favorable combination of traits are most likely to survive and reproduce, passing their genetic characters on to the next generation).

3. What are the three domains of life? To which domain do you belong?

The three domains of life are Archaea, Bacteria, and Eukarya. Humans belong to the domain Eukarya.

Principles of Population Ecology 1. What is the effect of each of the following on population size: birth rate, death rate, immigration, and emigration?

Populations change over time. On a global scale, this change is due to the rate at which individuals produce offspring (the birth rate, b) and the rate at which organisms die (the death rate, d). Therefore, the growth rate of the global population (r) is equal to the birth rate minus the death rate (r = b - d). In local populations, however, the movement of individuals from one region to another [immigration (i) and emigration (e)] factor into estimates of population size. Thus, the growth rate of a local population equals the (birth rate minus the death rate) plus (immigration minus emigration) or r = (b-d) + (i-e).

2. How do intrinsic rate of increase and carrying capacity produce the J-shaped and Sshaped population growth curves?

Chapter 5 The exponential growth of a population that occurs under ideal conditions (i.e., unlimited resources) is referred to as the intrinsic rate of increase. If you plot the population number versus time of a population exhibiting a large intrinsic rate of increase, the graph will produce a J shape curve. If, however, the population size reaches its carrying capacity (i.e., the limit of the environment’s ability to support a population), a characteristic S-shaped curve will result when the same variables are plotted.

3. What are two examples of density-dependent factors that affect population growth?

What are two examples of density-independent factors?

Density-dependent factors are environmental factors whose effects on a population change as population density changes. Examples of density-dependent factors that affect population growth include predation, disease, and competition. Density-independent factors are environmental factors that affect the size of a population but are not influenced by changes in population density. Examples of density-independent factors that affect population growth include random weather events, such as blizzards, hurricanes and fires.

4. What are the three main survivorship curves?

Survivorship is the probability that a given individual in a population will survive to a particular age. The three main survivorship curves are: (1) type I survivorship, in which death is greatest in old age; (2) type II survivorship, in which death is spread evenly across all age groups; and (3) type III survivorship, in which death is greatest among the young. Type I survivorship is typically exhibited by humans and elephants, while type III survivorship is typically exhibited by many fish species. Type II survivorship, however, is relatively rare in nature (i.e., only a few species of lizards are known to exhibit this type of survivorship).

5. How does a metapopulation differ from a local population?

A metapopulation is a set of local populations among which individuals are distributed in distinct habitat patches across a landscape. The distribution of local populations across the landscape occurs because of local differences in elevation, temperature, amount of precipitation, soil moisture, and availability of soil minerals.

Biological Communities 1. What is an ecological niche?

An ecological niche is the totality of an organism’s adaptations, its use of resources, and the lifestyle to which it is fitted. It is the organism’s role within the structure and function of an ecosystem. More specifically, the potential, idealized ecological niche of an organism is its fundamental niche; while the lifestyle an organism actually pursues and the resources it actually uses make up its realized niche.

Chapter 5 2. What is the principle of competitive exclusion? Of resource partitioning?

The principle of competitive exclusion holds that no two species can indefinitely occupy the same niche in the same community because one species will eventually exclude the other as a result of competition for limited resources. However, coexistence can occur if the overlap in the two species’ niches is reduced. When resources are used differently by various species, competition is reduced. This is referred to as resource partitioning.

3. What is symbiosis? What are the three kinds of symbiosis?

Symbiosis is any intimate relationship or association between members of two or more species. The three kinds of symbiosis include mutualism (both partners benefit), commensalism (one organism benefits and the other is neither harmed nor helped), and parasitism (one organism benefits while the other is adversely affected.

4. Describe how evolution has affected predator-prey relationships.

Predation, the consumption of one species by another, has resulted in the coevolution of both predator and prey strategies. Predators have evolved greater efficiencies in ways to catch prey, while prey has evolved better ways to escape from predators. Adaptations related to predator-prey interactions include predator strategies such as pursuit and ambush, and prey strategies such as plant defenses (spines, thorns, thick wax, etc.) and animal defenses (warning coloration, cryptic coloration, etc.).

5. What is a keystone species? Why do we consider the wolf a keystone species?

A keystone species is a species, often a predator, which exerts a profound influence on a community in excess of that expected by its relative abundance. The gray wolf is considered a keystone species because, in their absence, an entire ecosystem can significantly diminish in terms of biological diversity.

Species Richness in a Community 1. What are two determinants of species richness? Give an example of each.

Species richness is the number of species in a community. Determinants of species richness include: the abundance of potential ecological niches, closeness to the margins of adjacent communities, geographic isolation, dominance of one species over others, habitat stress, and geologic history. When the abundance of potential ecological niches is sizable (for example, in a complex community such as a tropical rain forest), species richness is usually greater. Likewise, species richness is usually greater at the margins of adjacent communities rather than in their centers, due to the variety of ecological niches available (for example, in ecotones). Species richness is inversely related to the geographic isolation of a community (as in isolated island communities), and reduced when any one species occupies a position of dominance within a community (i.e., species competition). Additionally, species richness tends to be inversely related to the

Chapter 5 environmental stress of a habitat (i.e., low species richness in a polluted stream), and greatly affected by the geological history of an area (i.e., large species richness in old, stable ecological communities such as tropical rain forests).

2. What are ecosystem services? Describe some ecosystem services a forest provides.

Ecosystem services are important environmental benefits that ecosystems provide to people. Ecosystem services provided by forests include: purification of air and water; production and maintenance of soil; absorption of carbon dioxide; wildlife habitats; wood production; and recreational areas for humans.

Community Development 1. What is ecological succession? How do primary and secondary succession differ?

The process of community development over time, which involves species in one stage being replaced by different species, is called ecological succession. When ecological succession begins in an environment that has not been inhabited before (i.e., on bare rock surfaces or recently formed volcanic lava), it is referred to as primary succession.

Secondary succession is the change in species composition that takes place after some disturbance destroys the existing vegetation. In secondary succession soil is already present.

Chapter 6 Major Ecosystems of the World Lecture Outline: I. Earth’s Major Biomes A. A biome is a large, relatively distinct terrestrial region with a similar climate, soil, plants, and animals i. It encompasses many interacting ecosystems ii. It is considered the next level of ecological organization above those of community, ecosystem, and landscape B. Tundra (arctic tundra): cold boggy plains of the far north i. Tundra is a treeless biome consisting of boggy plains covered by lichens and small plants such as mosses 1. It has harsh, cold winters and extremely short summers 2. It is characterized by little precipitation (4-10 inches/yr), permafrost, low species richness, and low primary productivity ii. Animal life includes lemmings, voles, weasels, arctic foxes, snowshoe hairs, ptarmigan, snowy owls, and musk oxen C. Boreal forests (taiga): conifer forests of the north i. Boreal forest is a region of coniferous forest (such as pine, spruce, and fir) in the Northern Hemisphere; located just south of the tundra 1. It has extremely cold, severe winters 2. It is characterized by little precipitation (20 inches/year), acidic/mineral poor soil, ponds, lakes, and cone-bearing evergreens ii. Animal life includes caribous, wolves, bears, moose, rodents, rabbits, lynx, sable and mink D. Temperate rain forest: lush temperate forests i. Temperate rain forest occurs on the northwest coast of North America, southeastern Australia and southern South America, and consists mostly of large evergreen trees, mosses, lichens, and ferns 1. Seasonal fluctuation is narrow; winters are mild and summers are cool 2. It is characterized by high precipitation (50 inches/year), dense fog, high species richness, and high primary productivity ii. Animal life includes squirrels, wood rats, mule deer, elk, birds, and several amphibian and reptile species E. Temperate deciduous forest: broad-leaved trees that shed their leaves i. Temperate deciduous forest occurs in temperate areas with a moderate amount of precipitation 1. It has wide seasonal fluctuation with hot summers and cold winters 2. It is characterized by moderate precipitation (30 – 60 inches/year), rich top soil, and broad-leaf hardwood trees that lose their foliage annually ii. Animal life includes large mammals (puma, wolves, bison, deer, bears) and many small mammals and birds F. Grasslands (tallgrass prairies): temperate seas of grass

Chapter 6 i. Temperate grasslands contain a profusion of grasses and other herbaceous flowering plants and few trees 1. It has wide seasonal fluctuation with hot summers and cold winters 2. It is characterized by moderate precipitation (10-30 inches/yr) and a mineral rich top layer of soil ideal for agriculture ii. Animal life includes grazing mammals such as pronghorn elk and bison, wolves, coyotes, prairie dogs, foxes, ferrets, birds of prey, grouse, reptiles, and insects G. Chaparral (mediterranean climates): thickets of evergreen shrubs and small trees i. Chaparral is a hilly temperate biome located around the Mediterranean Sea as well as in the North American southwest, southwestern and southern Australia, central Chile, and southwestern South Africa 1. It has mild winters with abundant rainfall combined and dry summers; files are common during summer months 2. It is characterized by low precipitation (mostly in winter),dense growth of evergreen shrubs, small trees, and thin, unfertile soil ii. Animal life includes mule deer, wood rats, chipmunks, lizards, and many species of birds H. Deserts: arid life zones i. Deserts are dry areas found in both temperate (cold deserts) and subtropical regions (warm deserts) usually with sparse plant cover of cacti, yuccas, Joshua trees and sagebrushes 1. The low water vapor content of the desert atmosphere results n daily temperature extremes of heat and cold; 2. They are characterized by low precipitation (less than 10 inches/yr), very little plant life, low species richness, and soil low in organic material but high in mineral content ii. Animal life includes small mammals, insects amphibians, and reptiles (most are desert adapted) I. Savanna: tropical grasslands i. Savannas are tropical grasslands with widely scattered trees or clumps of trees 1. They usually occur in areas of low and/or seasonal rainfall with prolonged dry periods, temperature varies little throughout the year, and seasons are regulated by precipitation 2. Annual precipitation is moderate (30-60 inches/yr), soil is low in nutrient minerals, both trees and grasses have fire-adapted features and protection against herbivores ii. Animal life includes hoofed mammals (antelope, giraffe, zebra elephants), large predators (lions and hyenas), many bird species, and cattle (present rangeland grazing is leading to desertification of savannas) J. Tropical rain forests: lush equatorial forests i. Tropical rain forests are lush, species-rich forest biomes that occur where the climate is warm and moist throughout the year 1. They are found in Central and South America, Africa, and Southeast Asia and are typically home to evergreen flowering plants, epiphytes, tall trees, and three distinct layers of vegetation

Chapter 6 2. It is characterized by high annual precipitation (80 – 180 inches/yr), ancient, highly weathered mineral-poor soil, high productivity, and high species richness ii. Animal life includes an enormous array of insects, reptiles, amphibians, birds, and mammals (sloths and monkeys) K. Vertical zonation: the distribution of vegetation on mountains i. The cooler temperatures at higher elevations of a mountain produce a series of ecosystems similar to the biomes encountered when going toward the North Pole (deciduous/temperate forest, subalpine coniferous/boreal forest, alpine/arctic tundra) ii. Types of organisms living on the mountain change as the temperature changes II. Aquatic Ecosystems A. Determinants of species composition in aquatic ecosystems include salinity, dissolved oxygen, light, temperature, pH, and presences or absence of waves and currents B. Aquatic ecosystems contain three main ecological categories of organisms i. Free-floating plankton 1. Phytoplankton are free-floating photosynthetic algae and cyanobacteria that form the base of most aquatic food webs 2. Zooplankton are nonphotosynthetic organisms that include protozoa, crustaceans, and the larval stages of many animals ii. Strongly swimming nekton (fishes, turtles, whales) iii. Bottom-dwelling benthos (sponges, oysters, barnacles, worms, clams, sea cucumbers, crawfish, insect larvae, brittle stars) C. Freshwater ecosystems (occupy only about 2% of Earth’s surface) i. Rivers and streams: flowing-water ecosystems 1. The concept of a river system as a single ecosystem with a gradient in physical features from headwaters to mouth is known as the river continuum concept 2. This gradient results in predictable changes in the organism inhabiting different parts of the river system ii. Lakes and ponds: standing-water ecosystems 1. A large lake has three zones a. The littoral zone is a shallow-water area along the shore of a lake or pond where light reaches the bottom; it is the most productive section of the lake b. The limnetic zone is the open water beyond the littoral zone; it extends down as far as sunlight penetrates to permit photosynthesis c. The profundal zone is beneath the limnetic zone; light does not penetrate effectively to this depth (no plants or algae found here) iii. Thermal stratification and turnover in temperate lakes 1. Thermal stratification is the marked layering of large temperate lakes caused by how far light penetrates it, causing temperature to change sharply with depth

Chapter 6 2.

Falling temperatures in fall, and rising temperatures in spring cause turnover, a mixing of the layers of lake water iv. Marshes and swamps: freshwater wetlands 1. Grasslike plants dominate in marshes, while woody trees and/or shrubs dominate in swamps 2. Wetlands are valued wildlife habitat for migratory birds, beaver, otters, muskrats, and game fishes 3. They provide natural flood control and serve as groundwater recharging areas D. Estuaries: where fresh and salt water meet i. Estuaries are among the most fertile ecosystems in the world ii. Temperate estuaries usually contain salt marshes which are important in preventing flood damage during storm surges iii. Mangrove forests are the tropical equivalent of salt marshes; they cover nearly 70% of tropical coastlines 1. Mangroves are breeding ground and nurseries for several commercially important fishes, shellfish, and birds 2. They also help prevent coastal erosion and provide a barrier against the ocean during storms/hurricanes E. Marine ecosystems i. The intertidal zone is the area of shore line between low and high tides ii. The benthic environment: seagrass beds, kelp forests, and coral reefs 1. The benthic environment consists of sediments (mostly sand and mud) where many animals burrow 2. Shallow benthic communities are particularly productive a. Seagrass beds are flowering plants adapted to complete submersion in salty ocean water; they are areas of high primary productivity and help stabilize sediments, reducing surface erosion b. Kelp forests provide habitats for many marine animals; the diversity of life supported by kelp forests rivals that found in coral reefs c. Coral reefs are found in warm shallow seawater; they consist of colonies of millions of tiny coral animals, which require light for zooxanthellae (the symbiotic algae that live and photosynthesize in their tissues) i. Coral reefs are ecologically important because they provide a habitat for many kinds of marine organisms and protect coastlines from shoreline erosion ii. There are three main types of coral reefs 1. Fringing reefs are directly attached to the shore of a volcanic island or continent 2. Atolls are circular coral reefs that surround a central lagoon of quiet water 3. Barrier reefs are separated from nearby land by a lagoon of open water

Chapter 6 iii. Various human activities cause serious threats to the health of coral reefs (runoff, overfishing, disease, etc.)

3. Deeper parts of the benthic environment are divided into three zones a. Bathyal benthic zone – 200m to 4000m b. Abyssal benthic zone – 4000m to 6000m c. Hadal benthic zone – 6000m to the bottom of the deepest trenches iii. The pelagic environment: the vast marine system 1. The pelagic environment consists of all of the ocean water, from the shoreline down to the deepest ocean trenches a. The upper reaches of the pelagic environment comprise the euphotic zone b. The euphotic zone spans from the surface to 150m deep 2. The two main divisions of the pelagic environment are the neritic and oceanic provinces a. The part of the pelagic environment that overlies the ocean floor from the shoreline to a depth of 200m is referred to as the neritic province b. The part of the pelagic environment that overlies the ocean floor at depths greater than 200m is referred to as the oceanic province iv. A national marine sanctuary is a marine ecosystem set aside to minimize human impacts and protect unique natural resources and historical sites 1. The U.S. has 14 national marine sanctuaries along the Atlantic, Pacific, and Gulf of Mexico coasts 2. They include kelp forests, coral reefs, fishing grounds, deep submarine canyons and shipwrecks

Chapter 6

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Recognizing Biomes

Time: Materials: Handouts:

0 minutes prep; 15 – 25 minutes in class None None

Procedures:

First, have students vote (anonymously) for the kind of biome your campus is located in. First, have them make a guess, then have them do research on the internet to find exact climate data for your area.

Discuss: was your intuitive sense accurate? Why or why not.

Next, have each student identify the farthest away location that they have visited. What sort of biome was it? How do we know? Again, use the internet to find the data you would need to confirm this biome. Discuss how plant and animal life (including behavior of humans in that location) differ from those in your region.

Student See above Instructions:

Specific Suggestions:

None

Objectives:

Define biome and describe some of the major terrestrial biomes.

Chapter 6

Instructor Notes for In-Class Activity 2 Title:

Drilling for Oil in the Tundra

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) Internet access None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: Extracting Oil from the Alaskan National Wildlife Refuge will have a minimal impact on local plants and animals.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions: Specific

The instructor is likely to have to serve as a facilitator or moderator from

Chapter 6 Suggestions:

time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Relate human effects on biomes.

Chapter 6

Instructor Notes for In-Class Activity 3 Title:

Field Trip: Zoo, Botanical Gardens, Natural History Museum or Campus

Time: Materials: Handouts:

5 – 30 minutes prep; Full class period None Printed materials from the destination, if available

Procedures:

Visit a local zoo, botanical garden, natural history museum or even your campus. Have students take notes on the types of animals and plants from biomes other than your regions biome. In the cases of living organisms, discuss what steps people have to take to maintain those organisms.

Upon returning to class, discuss your findings.

Student Prepare your own definition of a biome. Then, during the field trip, think Instructions: about how completely your definition captures the examples you encounter. Adapt your definition as necessary.

Specific Suggestions:

Have specific students assigned to discuss and then look into a specific biome.

Objectives:

Define biome and describe at least one of the major terrestrial or aquatic biomes.

Chapter 6

Instructor Notes for In-Class Activity 4 Title:

Travel to a Biome

Time:

5 minutes prep; 60 minutes out of class time; one class period for presentations None None

Materials: Handouts: Procedures:

Divide the class into groups of two or three individuals. If there are 30 in the class have groups of three, if there are fewer students, groups of two work best.

Have each group draw a biome out of a hat. This way you are not assigning a biome and the student have more control over what they putting together. Each student group is to come up with a travel agency name and they will try and recruit their classmates to go on a trip to their biome. Artic biome and Aquatic biomes are great challenges. The students will then go and put a presentation with flyers, prices, a power point presentation explaining their biome and why we would want to vacation at this particular biome. They must put the temperatures, conditions, what we need to bring, what kind of activities take place, what animals or plants live in this biome etc.

On the presentation day, they will be presenting this biome as a marketing tool to get us to venture to the desert, mountains, tropical rain forests etc.

At the end of the presentations, the student group with the most votes to travel to that biome will receive additional 25 points for the assignment.

Other rewards could be given, like a travel bag from a travel agency etc.

Student You and your team will need to come up with the ideal vacation to go to Instructions: your chosen biome. You will make a power point presentation on your biome giving information on the temperatures, activities, who and what lives there, what we need to bring, how much it will cost and why we should choose your biome over the other biomes that will be presenting.

Specific Suggestions:

None

Objectives:

Describe the different biomes and their impact on our ecology.

Identify different characteristics of a biome and the impact to living organism in that biome.

Chapter 6

Instructor Notes for In-Class Activity 5 Title:

Finger shuffle board

Time: Materials:

25 minutes prep; 15 – 25 minutes in class.

Blow up Figure 6.2 to 8x11 size put shuffle board points on each shelf and laminate it. Have enough for each student.

Each student can supply their own penny but you should have enough for each student if needed.

Hand out Figure 6.2 which is laminated with points on it.

Handouts: Procedures:

Pass out the shuffle boards to each student, they will pair up into two students per group. They will sit across from each other with their laminated shuffle board paper, a penny each.

Each student takes a turn and shoots their penny toward the board with the blue point facing them. They must describe the biome they hit and list some benefits of that biome. If they state one point they get the points they hit. If they cannot describe the biome, or give a point not given they will lose that number of points. The person who has the most points in a 15-minute period advances to the next level. This is a good way to study for the biomes.

Student Have your biome shuffleboard pictures pointing away from you.

Instructions: Face your partner.

Decide who goes first and that person will then flick his/her penny towards the board across from them.

When the penny falls on a field or biome, they are to describe one point of that biome. It could be the average temperature, type of animals or plants that live in that biome, why this particular biome is good for our environment etc. If they state one fact, they get the points on the board.

Specific Suggestions: Objectives:

Each person keeps track of their points and after 15 minutes the person with the most points advances to the next level which is another class member that has the most point. The game is then started all over until there is a classmate with the top points. You carry your points from one game to the next.

None • •

Describe the different biomes.

List or describe the benefits of the biomes in our environment.

Chapter 6

Answers to Critical Thinking and Review End of Chapter Questions: 1.What two climate factors are most important in determining an area’s characteristic biome?

Ans: Biomes are primarily determined by temperature and precipitation.

2. Offer a possible reason why the tundra has such a low species richness.

Ans: The limited precipitation in combination with low temperatures, flat topography (surface features), and permafrost all provide reasons for the tundra’s low species richness. Few species have adapted to this environment. Another reason for low species richness may be the short growing season which results in low primary productivity.

3. Describe representative organisms of the forest biomes discussed in the text: boreal forest, temperate deciduous forest, temperate rain forest, and tropical rain forest.

Ans: Black and white spruces, balsam fir, eastern larch, and other conifers (cone-bearing evergreens) dominate the boreal forest. Conifers have many drought-resistant adaptations, such as needlelike leaves with a minimal surface area for water loss. Such adaptations let conifers withstand the “drought” of the northern winter months when roots cannot absorb water because the ground is frozen. Being evergreen, conifers resume photosynthesis as soon as warmer temperatures return. Animals in the boreal forest include; caribou, which migrate from the tundra in the summer, wolves, bears, moose, lynx, sable, and mink. Most species of birds are abundant in the summer but migrate to warmer climates for winter.

The temperate deciduous forest is dominated by broad-leaved hardwood trees, such as oak, hickory, maple, and beech; all of which lose their foliage annually. The trees of the temperate deciduous forest form a dense canopy that overlies saplings and shrubs.

Temperate deciduous forests originally contained a variety of large mammals, such as puma, wolves, and bison, which are now absent, plus deer, bears, and many small mammals and birds.

The dominant plants in the North American temperate rain forest are large evergreen trees such as western hemlock, Douglas fir, western red cedar, Sitka spruce, and western arborvitae.

Temperate rain forests are rich in epiphytic vegetation—smaller plants that grow on the trunks and branches of large trees. Epiphytes in this biome are mainly mosses, club mosses, lichens, and ferns; all of which also carpet the ground. Deciduous shrubs such as vine maple grow wherever a break in the overlying canopy occurs. Squirrels, wood rats, mule deer, elk, numerous bird species, and several species of amphibians and reptiles are common temperate rainforest animals.

No single species dominates the tropical rain forest. The trees of tropical rain forests are typically evergreen flowering plants. Their roots are often shallow and concentrated near the surface in a mat. The root mat catches and absorbs almost all nutrient minerals released from leaves and litter by decay processes. Swollen bases or braces called buttresses hold the trees upright and aid in the extensive distribution of the shallow roots. Little light penetrates to the understory, and many plants living there are adapted to climb already established host trees. Not counting bacteria and other soil-dwelling organisms, about 90% of tropical rainforest organisms live in the upper canopy. Rainforest animals include the most abundant and varied insects, reptiles, birds and

Chapter 6 amphibians on Earth. Most rainforest mammals, such as sloths and monkeys, live only in the trees and rarely climb to the ground.

4. Which biome discussed in this chapter is depicted by the information given below? Explain your answer?

Ans: Tropical Rainforests. Tropical Rainforests are characterized by abundant year-round rainfall, warm year-round temperatures, and mineral poor soils.

5. In which biome do you live? If your biome does not match the description given in this book, how do you explain the discrepancy?

Ans: Answers will vary 6. Which biomes are best suited for agriculture? Explain why each of the biomes you did not specify is less suitable for agriculture.

Ans: The biomes most suited for agriculture are temperate deciduous forest and grasslands.

Tundra is not suitable for agriculture because it is to cold and has water logged soil. Boreal forest is not suitable because it has a short growing season and mineral poor soil. Chaparral and savanna biomes have evolved with fire and need frequent fires to release nutrients back into the soil. Desert biomes are too dry for most agricultural products. Tropical rain forests are not good for agriculture because little organic matter accumulates in the soil.

7. What human activities are harmful to deserts? To grasslands? To forests?

Ans: Off-road vehicles damage desert vegetation, which sometimes takes years to recover. When the top layer of desert soil is disturbed, erosion occurs more readily, and less vegetation grows to support native animals. In some savanna grasslands, severe overgrazing and harvesting of trees

Chapter 6 for firewood have converted savanna to desert, a process called desertification. In all forests, overharvesting leads to deforestation and lost of species habitat.

8. Which biome do you think is in the greatest immediate danger from human activities? Why? Ans: Answers will vary 9. As you walk from the bottom to the top of a mountain, what changes in vegetation would you expect to see?

Ans: Hiking up a mountain is similar to traveling toward the North Pole with respect to the major ecosystems encountered. This change occurs due to the drop in temperature as one travels up the mountain. At the base of the mountain one would encounter vegetation normally found in Temperate forests. Moving up the mountain you would pass through vegetation representative of a Boreal forest followed by Artic tundra and finally at the top of the mountain a polar region.

10. What are two important abiotic factors that affect aquatic ecosystems?

Ans: The two most important factors that affect aquatic ecosystems are salinity and dissolved oxygen. Salinity and dissolved oxygen levels will determine what organisms will be found in the aquatic ecosystem.

11. Explain the role of freshwater wetlands in water purification.

Ans: One of freshwater wetlands most important roles is to help cleanse water by trapping and holding pollutants in the flooded soil. Wetlands also provide natural flood control because they are holding areas for excess water when rivers flood their banks. The floodwater stored in wetlands then drains slowly back into the rivers, providing a steady flow of water throughout the year. Wetlands serve as groundwater recharging areas.

12. If you were to find yourself on a boat in the Chesapeake Bay, what aquatic ecosystem would you be in? What ecosystem would you be in if you were in the middle of Everglades National Park?

Ans: The Chesapeake Bay is an estuary- a coastal body of water, partly surrounded by land, with access to the open ocean and a large supply of fresh water from a river. Everglades National Park is a salt marsh- shallow wetlands dominated by salt-tolerant grasses.

13. Which aquatic ecosystem is often compared to a tropical rain forest? Why? Ans: Coral reef ecosystems are the most diverse of all marine environments. They contain thousands of species of fishes and invertebrates, such as giant clams, snails, sea urchins, sea stars, sponges, flatworms, brittle stars, sea fans, shrimp, and spiny lobsters. The Great Barrier Reef occupies only 0.1% of the ocean's surface, but 8% of the world's fish species live there. The multitude of relationships and interactions that occur at coral reefs is comparable only to tropical rain forests among terrestrial ecosystems.

Chapter 6

14. What is the largest marine environment, and what are some of its features?

Ans: The oceanic province is the largest marine environment, comprising about 75% of the ocean's water; the oceanic province is the open ocean that does not overlie the continental shelf.

Most of the oceanic province is loosely described as the “deep sea.” All but the surface waters of the oceanic province have cold temperatures, high hydrostatic pressure, and an absence of sunlight. These environmental conditions are uniform throughout the year.

15. Which of the ocean zones shown would be home to each of the following organisms: lobster, coral, mussel, porpoise, and dragonfish. For those organisms you identify as living in the pelagic environment, are they most likely found in the neritic or oceanic province? Explain your answers.

Ans: Lobsters are found in the Benthic environment and can be found anywhere from the shoreline to beyond the edge of the continental shelf. Mussels are also found in the Benthic environment and can be found in low and mid intertidal zones, some mussels live in salt marshes, bays and even the surf. Coral is found in the Benthic environment and can be found in both tropic and subtropical waters. Porpoise live in the Pelagic environment. Most Porpoises live near shores in the neritic province but can also be found in the oceanic provinces. Dragonfish live in deep water in the oceanic provinces.

16. What would happen to the organisms in a river, with a fast current, if a dam were built?

Explain your answer.

Ans: In streams with fast currents, the inhabitants may have adaptations such as hooks or suckers to attach themselves to rocks so that they are not swept away. A dam causes water to back up, flooding large areas of land and forming a reservoir, which destroys terrestrial habitat. Below the dam, the once-powerful river is often reduced to a relative trickle, which alters water temperature, sediment transport, and delta replenishment and prevents fish migrations. The

Chapter 6 organisms that are adapted for fast currents will be out competed by species better suited for the new conditions.

17. Explain how coral reefs are vulnerable to human activities.

Ans: Globally, many coral reefs are at risk. In some areas, silt washing downstream from clearcut inland forests has smothered reefs under a layer of sediment. In addition to pollution from coastal runoff, overfishing, fishing with dynamite or cyanide, disease, and coral bleaching are serious threats. Land reclamation, tourism, oil spills, boat groundings, anchor draggings, hurricane damage, ocean dumping, and the mining of corals for building material also take a toll.

18. Briefly discuss two major human-caused problems in the ocean.

Ans: Answers may include any two of the following: Coastal and marine ecosystems receive pollution from land, from rivers emptying into the ocean, and from atmospheric contaminants that enter the ocean via precipitation. Disease-causing viruses and bacteria from human sewage contaminate seafood, such as shellfish, and pose an increasing threat to public health. Millions of tons of trash, including plastic, fishing nets, and packaging materials, find their way into coastal and marine ecosystems. Less visible contaminants of the ocean include fertilizers, pesticides, heavy metals, and synthetic chemicals from agriculture and industry. Offshore mining and oil drilling pollute the neritic province with oil and other contaminants. Millions of ships dump oily ballast and other wastes overboard in the neritic and oceanic provinces. Fishing is highly mechanized, and new technologies detect and remove every single fish in a targeted area of the ocean.

19. Scientists report that in recent years tropical ocean waters have become saltier, whereas polar ocean waters have become less salty. What do you think is a possible explanation for these changes?

Ans: As the global climate changes, evaporation around the equator has increased, leading to saltier water. At the poles, warmer temperatures have led to increases in glacial melting and runoff into the oceans, decreasing the salinity.

Answers to Review Questions Earth’s Major Biomes 1. What is a biome? What climate and soil factors produce each of the major terrestrial biomes?

A biome is a large, relatively distinct terrestrial region with similar climate, soil, plants, and animals, regardless of where it occurs in the world.

Tundra: The general climate in the tundra is characterized by low temperatures and little precipitation; only 4 to 10 inches per year. Most tundra soils are geologically young, nutrient-poor, and have little organic litter. Due to the tundra’s characteristic long, harsh

Chapter 6 winters, most of the tundra is enveloped by a layer of permafrost. The soil does however melt at the surface during the short summers.

Boreal Forests: Climate in boreal forests is generally characterized by extremely cold and severe winters, and summers a bit longer than in the tundra. Boreal forest receives little precipitation (20 in. per year), and its soil is typically acidic and mineral-poor with a deep layer of partly decomposed pine and spruce needles at the surface. Permafrost is patchy, and is often only found deep under the soil.

Temperate Rain Forests: Annual precipitation in this biome is high (more than 50 in. per year), and is augmented by condensation of water from coastal fogs. The proximity of temperate rain forest to the coastline moderates the temperature. Because of this, seasonal fluctuation is narrow and winters remain mild while summers stay cool.

Temperate rain forests typically exhibit relatively nutrient-poor soil, although its organic content may be high.

Temperate Deciduous Forest: Hot summers and cold winters are characteristic of the temperate deciduous forest, which occurs in temperate areas with moderate to high precipitation (30 to 60 in. per year). Typically, the soil of a temperate deciduous forest consists of a topsoil rich in organic material and a deep, clay-rich lower layer.

Grasslands: In grasslands, summers are hot, winters are cold, and rainfall is often uncertain. Annual precipitation averages between 10 to 30 inches annually. Grasslands have characteristically rich soil that has considerable organic material.

Chaparral: Chaparral biomes exhibit mild winters with abundant rainfall combined with hot, dry summers. Precipitation is moderate to low. Chaparral soil is thin and often not fertile.

Deserts: Deserts are dry areas found in both temperate (cold deserts) and subtropical regions (warm deserts). The low water vapor content of the desert atmosphere results in daily temperature extremes of heat and cold. Deserts vary depending on the amount of precipitation they receive, which is generally less than 10 inches per year. As a result of sparse vegetation, desert soil is low in organic material but is often high in mineral content. In some desert regions, the concentration of certain soil minerals reaches levels toxic to many plants.

Savanna: Savanna biomes occur in areas of low rainfall or seasonal rainfall with prolonged dry periods. Temperatures in tropical savannas vary little throughout the year, and seasons are regulated by precipitation, not by temperature as they are in temperate grasslands. Annual precipitation is 30 to 60 inches. Savanna soil is somewhat low in essential nutrient minerals, but rich in aluminum.

Tropical Rain Forests: Tropical rain forests occur where temperatures are warm throughout the year and precipitation occurs almost daily. The annual precipitation of a tropical rain forest is typically 80 to 180 inches per year. Much of this precipitation comes from locally recycled water that enters the atmosphere by transpiration of the forest’s own trees. Tropical rain forest commonly occurs in areas with ancient, highly weathered, mineral-poor soil. The nutrient minerals of these forests are tied up in the vegetation rather than the soil.

2. Which biome, in your opinion, has suffered the most deleterious effects from human activities? Explain your answer.

Chapter 6 Answers will vary.

In my opinion, tropical rain forests have suffered the most deleterious effects from human activities. In fact, human population growth and industrial expansion in tropical countries could spell the end of tropical rain forests during the 21st century. Biologists recognize that many rainforest species will become extinct before they are even identified and scientifically described.

3. How does vegetation change with increasing elevation and latitude?

There is an elevation-latitude similarity that occurs as one ascends a mountain and/or travels north due to the drop in temperature associated with both. Respective vegetation also changes with both an increase in elevation and latitude. For example, at the base of a mountain one would find deciduous trees. At higher elevations, where the climate is colder and more severe, this vegetation changes to coniferous subalpine forest (similar to the boreal forest of the north). Higher still, where climate is quite cold, alpine tundra occurs (similar to the arctic tundra found north of the boreal forest), and the top of the mountain might have a permanent ice or snow cap, similar to that in polar areas.

Aquatic Ecosystems 1. What environmental factors are most important in determining the kinds of organisms found in aquatic environments?

In aquatic ecosystems, important environmental factors include salinity, amount of dissolved oxygen, and availability of light for photosynthesis.

2. How do you distinguish between freshwater wetlands and estuaries? Between flowingwater and standing-water ecosystems? Between the neritic and oceanic provinces?

Freshwater wetlands are lands that shallow fresh water covers for at least part of the year, while an estuary is a coastal body of water, partly surrounded by land, with access to the open ocean and a large supply of fresh water from a river.

Flowing-water ecosystems are freshwater ecosystems such as rivers or streams in which the water flows in a current. Standing-water ecosystems are bodies of fresh water that are surrounded by land and do no flow (i.e., lakes or ponds).

The pelagic environment consists of all the ocean water, from the shoreline down to the deepest ocean trenches. The two main divisions of the pelagic environment are the neritic and oceanic provinces. The neritic province is the part of the pelagic environment that overlies the ocean floor from the shoreline to a depth of 200 m. The oceanic province is the part of the pelagic environment that overlies the ocean floor at depths greater than 200 m.

3. In your opinion, which aquatic ecosystem is most vulnerable to human activities?

Explain your answer.

Answers will vary.

Chapter 6 In general, all aquatic ecosystems are subject to human-produced pollution (i.e., sewage, discharge, agricultural runoff, oil spill, and trash). However, in my opinion, freshwater wetlands are the most vulnerable to human activities. Over the last century, freshwater wetlands have been filled in or drained so that farms, housing developments, and industrial plants could be built. They have also been threatened by agriculture, pollution, and dam construction. This is tragic, considering the numerous ecosystem services provided by naturally occurring freshwater wetlands.

Chapter 7 Human Health and Environmental Toxicology Lecture Outline: I. Human Health A. Two indicators of human health in a given country are life expectancy (how long people are expected to live) and infant mortality (how many infants die before the age of one) B. Health issues in highly developed countries i.

Average life expectancy for American women is 80 and 75 for American men ii. A significant fraction of premature deaths in the United States is caused in part by individual lifestyle habits (poor diet, lack of exercise, smoking) iii. Healthcare professionals use the body mass index (BMI) to determine whether a person is overweight and/or obese C. Health issues in developing nations i.

Malnutrition, unsafe water, poor sanitation, and air pollution still prevail in many less developed countries despite gradual improvements in sanitation and drinking water ii. Average overall life expectancy for developing countries is 65 iii. Average overall life expectancy for the very poorest developing countries is <45 iv.

18% of the 57 million deaths that occur worldwide each year are children less than 5 years of age D. Emerging and reemerging diseases i.

Emerging diseases are infectious diseases that were not previously found in humans; they typically jump from an animal host to the human species (i.e., HIV/AIDS, Lyme disease, West Nile virus, influenza (new strains), SARS, Ebola) ii. Reemerging diseases are infectious diseases that existed in the past but for a variety of reasons are increasing in incidence or in geographic range (i.e., tuberculosis, yellow fever, malaria, dengue fever) iii. The main factors involved in the emergence or reemergence of infectious diseases include 1. Evolution of the infectious organisms 2. Evolution of antibiotic resistance 3. Urbanization (overcrowding, poor sanitation) 4. An increase in elderly who are more susceptible to infection 5. Pollution, environmental degradation, changing weather patterns 6. Growth in international travel and commerce 7. Poverty and social inequality II. Environmental Pollution and Disease A. Persistence, bioaccumulation, and biological magnification of environmental contaminants

Chapter 7 i.

Persistence is a characteristic of certain chemicals that are extremely stable and may take years to be broken down in to simpler forms by natural processes ii. Bioaccumulation is the buildup of a persistent toxic substance iii. Biological magnification is the increased concentration of toxic chemicals in the tissues of organisms that are at higher levels in food webs 1. Toxic substances that exhibit all three of these characteristics include certain pesticides (DDT), radioactive isotopes, heavy metals (lead/mercury), flame retardants (PBDEs), and industrial chemicals (PCBs) 2. Natural decomposers (bacteria) have not yet evolved ways to degrade many synthetic pesticides, therefore leading to the accumulation of pesticides in the environment and food web B. Endocrine disrupters are chemicals that mimic or interfere with the actions of the endocrine systems in humans and wildlife 1. Examples include chlorine-containing industrial compounds (PCBs and dioxins), heavy metals (lead and mercury), pesticides (DDT, kepone, dieldrin, chlordane, endosulfan), flame retardants (PBDEs), and certain plastics and plastic additives such as phthalates a. Phthalates are ingredients in cosmetics, fragrances, nail polish, medications, and common plastics used in food packaging, toys and household products b. Phthalates have been implicated in birth defects and reproductive abnormalities c. Like hormones, they are active at very low concentrations and appear to alter reproductive development in males and females of various animal species 2. Hormones are chemical messengers produced by organism in minute quantities to regulate growth, reproduction and other important biological functions III. Determining Health Effects of Environmental Pollution A. All chemicals, even “safe” chemicals such as sodium chloride (table salt), are toxic if exposure is high enough B. The study of toxicants, or toxic chemicals, is called toxicology i.

Toxicity is measured by the extent to which adverse effects are produced by various doses of a toxicant 1. Acute toxicity, which ranges from dizziness and nausea to death, occurs immediately to within several days following a single exposure 2. Chronic toxicity generally produces damage to vital organs, following a long-term, low-level exposure to chemicals ii. One complication of toxicology is that each individual’s genes largely determine that person’s response to a specific toxicant 1. Environmental susceptibility genes affect how the body metabolizes toxicants 2. Other gene variations allow certain toxicants to bind strongly – or less so – to DNA

Chapter 7 iii.

Children and chemical exposure 1. Children are more susceptible to most chemicals than are adults because their bodies are still developing and are not as effective in dealing with toxicants 2. Pesticides and children a. The EPA estimates that 84% of U.S homes use pesticide products b. More than 65,000 reports of exposure and possible poisoning from household pesticides, involving children, occur each year 3. Identifying cancer-causing substances a. Toxicology and epidemiology are the two most common methods for determining whether a chemical causes cancer b. Although epidemiological studies have the advantage that they look at people who were actually exposed to the chemical, several limitations still exist i. It is difficult to reconstruct, or estimate, historical doses ii. Various confounding factors exist (additional exposures) iii. Individuals respond differently iv.

Chemical mixtures interact by additivity, synergy, or antagonism 1. Additivity – the effect is exactly what one would expect, given the individual effects of each component of the mixture (1+1=2) 2. A synergistic chemical mixture has a greater combined effect than expected (1+1=3) 3. An antagonistic interaction in a chemical mixture results in a smaller combined effect than expected (1+1=1.3) IV. Ecotoxicology: Toxicant Effects on Communities and Ecosystems A. There has been a paradigm shift in the way people think about toxicant effects on communities and ecosystems i.

People used to think - and some still do – that “the solution to pollution is dilution” (the dilution paradigm) ii. Today virtually all environmental scientists have rejected the dilution paradigm in favor of the boomerang paradigm – “what you throw away can come back and hurt you” B. Ecotoxicology (aka environmental toxicology) studies contaminants in the biosphere, including their harmful effects on ecosystems i.

Its scope is broad – from molecular interactions to global climate change ii. It helps policymakers determine the costs and benefits of the many industrial and technological “advances” that affect us and the ecosystems 1. Obtaining higher-level information is complicated because natural systems are exposed to many environmental stressors 2. Also, natural systems must be evaluated for extended periods to establish trends, and results must be clear enough for evaluation by policymakers and the public V. Decision Making and Uncertainty: Assessment of Risks A. Risk management is the process of identifying, assessing, and reducing risks

Chapter 7 i.

Risk is the probability that a particular adverse effect will result from some exposure or condition ii. A hazard is a condition that has the potential to cause harm iii. Effective risk management cannot be based on calculated risks alone, but must also account for intuition, trust, and social conditions B. Cost-benefit analysis of risks analyzes the estimated cost of some regulation to reduce risk compared with potential benefits associated with that risk reduction C. The precautionary principle is the idea that no action should be taken or product introduced when the science is inconclusive and unknown risks may exist; it puts the burden of proof on the developers D. Ecological risk assessment involves hazard identification, dose-response assessment, exposure assessment, and risk characterization

Chapter 7

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Contrasting Human Health Issues in the Developed and Developing World

Time: Materials: Handouts:

5 – 10 minutes prep; 15 – 20 minutes in class Tally master sheet or template (see below) One

Procedures:

Distribute handouts to all students. Students will spend one or two minutes filling out a worksheet that assesses the types of diseases and other causes of death they have encountered at a personal level. They will then tally their results in small groups, and discuss any uncertainties they may have encountered. One student will then report back to the larger group, and the instructor or a student will tally the list for the full class.

This list will represent diseases familiar to the US. The instructor can then challenge the students to think about rates of the same diseases and causes of death in less developed countries.

Student Fill out the worksheet. Then, working in groups of 3 - 4, tally your Instructions: group’s results, and talk about any uncertainties you may have. Choose one member of your group to report back to the class.

After full class has been tallied, ask students to return to their group of 3 – 4, and discuss this question: how do you think these numbers would differ in a less developed country (perhaps Bangladesh or Zaire). Why? Would the differences be more pronounced among the young, middle aged, or old?

Have groups take turn reporting their ideas back to the full class (number of ideas per group will depend on total size of class).

Specific Suggestions:

Objectives:

1. Prepare a master tally sheet for the classroom—whether an overhead, PowerPoint slide or template to copy onto the board.

2. Feel free to add other “conditions” to the table below, or allow students to add other conditions by adding blank lines.

3. Be sure to ask whether any students are from or have personal contacts in developing countries.

Contrast health issues in highly developed and developing countries

Chapter 7 In-Class Activity 1: Handout

Condition

Malaria Obesity Heart Disease Diarrhea (infant) Tuberculosis Car accident Polio HIV / AIDS Starvation

Know someone who has or has had the condition

Know someone who has died from the condition

Have heard of someone in US with the condition

Have heard of someone in US who has died from the condition

Chapter 7

Instructor Notes for In-Class Activity 2 Title:

Estimating Bioaccumulation: DDT in a lake

Time:

5 - 10 minutes prep; 15 - 25 minutes in class (depends on students’ math skills) Calculators or computers with spreadsheets One (see below)

Materials: Handouts: Procedures:

Students will calculate a hypothetical bioaccumulation of the common lipophilic pesticide DDT as it progresses through the food chain from algae to fish to humans. First, students will work through an example calculation: a starting concentration of DDT found in algae is used that to calculate the total amount of DDT consumed by a shrimp. The amount consumed by the shrimp divided by the weight of the shrimp will yield an approximate concentration of DDT in the shrimp. A similar calculation will yield the concentration of DDT in a fish, and another will yield the concentration in an adult human.

Student Complete the calculations on the worksheet below.

Instructions: Specific Suggestions:

Objectives:

1. Assess the math skills of your students before doing this exercise.

If they have solid basic math skills, they should be able to do this alone. Alternatively, have them work in small groups.

2. If you have access to computers, these equations can easily be set up in a spreadsheet program.

3. For advanced students, consider varying the various consumption rates and body weights, consider the case of children, and / or plot the bioaccumulation in humans as they age.

Demonstrate how bioaccumulation can lead from small exposures to large exposures through the food chain.

Chapter 7 In-Class Activity 2: Handout Estimating Bioaccumulation: DDT in a Lake (Note: this is a hypothetical example.)

A medium sized lake can serve as a major food source for a subsistence community. Suppose that a community of about 100 people gets much of its protein from fishing on such a lake. Every day, each person eats one or two fish, which weigh on average about 150 grams. The fish feed primarily on shrimp, as well as insects and other small animals. You have learned that an alga that is one of the primary food sources for shrimp in the lake is contaminated with DDT, a persistent organic pesticide that farmers upstream have begun using to control ants in food crops.

You want to know how much of this DDT might eventually end up in members of the community.

The following shows how to calculate the concentration of DDT in the shrimp, given the concentration in algae and the eating habits of the shrimp.

Knowns: ▪ Algae contain about 0.0002 mg of DDT per gram of algae. That is about 0.2 parts per million (ppm).

▪ Over its (short) life, a shrimp will grow to weigh about 1 gram ▪ The average shrimp eats about 10 grams of contaminated algae during its life.

The amount of DDT consumed by the shrimp can then be calculated: DDT consumed by shrimp = amount algae consumed × concentration of DDT in algae So ▪ DDT consumed by shrimp = 10 galgae × 0.0002 mgDDT per galgae = 0.002 mgDDT ▪ ▪

Since a shrimp weighs 1 gram, the concentration of DDT in the shrimp is 0.002 mgDDT / gshrimp, or about 2 ppm

▪

This assumes that ALL of the DDT consumed by the shrimp stays in its body (a “worst case” assumption that is probably not true).

Now, use this same method to estimate the eventual concentration of DDT in fish and in humans, given the following information: ▪ The average fish eats about 1.7 kg of shrimp as it grows to weigh 150 g.

▪ The average person eats 1 – 2 fish per day over a 60 year life.

▪ The average adult weighs about 70 kg.

▪ Note that you will have to compute the total amount of fish eaten by multiplying the amount eaten per day by the number of days in the individual’s life.

Chapter 7

Instructor Notes for In-Class Activity 3 Title:

Creating and Interpreting Dose-Response Curves

Time: Materials: Handouts:

10 minutes prep; 15 - 25 minutes in class None Instruction sheet, graphs

Procedures:

Students will chart

Student Working in groups of 3-4, create a Dose-Response curve given the data Instructions: and instructions on the worksheet. Use this dose-response curve to answer the questions on the worksheet. Discuss as a class.

Specific Suggestions:

Provide students with multiple copies of the graph sheet.

Consider using additional real or hypothetical dose-response data so that students will see a range of possible curves, including thresholds and even hormetic (beneficial) effects as shown in the Environmental news clip.

Objectives:

Describe how a dose-response curve helps determine the health effects of environmental pollutants.

Chapter 7 In-Class Activity 3: Handout 1 Suppose that some mice are fed a chemical called EMBS every day for about two years. They are then tested for cancer. The results of this test are listed in the table below. Note that animals are usually given doses based on their body weights, so smaller animals would get relative small total doses, but still the same in proportion to their weights.

Dose (mg EMBS / kgmouse body weight / day) 0 3 6 12

Number of mice 73 69 75 75

Number of mice with tumors 0 7 16 30

P(Cancer)

0.10

 7 / 69

1. What do these data tell us about the carcinogenic potential of EMBS? a. Can it cause cancer in mice? b. Can it cause cancer in humans?

2. Fill in the fourth column, using the example provided as a guide 3. Graph the EMBS dose-response curve on the following page. Does EMBS appear to have a threshold for mice?

4. Suppose you fed another group of mice 24 mg EMBS / kgmouse body weight / day. How many would you expect to get cancer? Why? 5. Suppose you fed yet another group of mice 1 mg EMBS / kgmouse body weight / day. How many would you expect to get cancer? Why?

Chapter 7

Instructor Notes for In-Class Activity 4 Title:

Populations and disease

Time: Materials: Handouts:

5 minutes prep; 60 minutes in or out of class Internet access None

Procedures:

Divide the students into groups and assign them a continent of the world.

They can either draw their continent out of a hat or sign up for one. The continents are Australia, North America, South America, Africa, Asia, Europe instead of Antarctic use the islands of the word.

After the students are divided into continents have them research the populations for their continents and the various diseases for the current time period. Have them make a graft or some visual to explain to the class their findings. A second part to this activity is to go back 100 years and find the population and what disease have gone through their continent. Have the diseases changed, have the populations increased or decreased etc. When they come up with these facts they can superimpose them over the previous graft and relate the difference, if significant.

Student Instructions:

Choose a continent from the following: Australia Asia Africa Europe North America South America World islands (this is not a continent, but is full of information) Research the population of your continent and the diseases of this time period.

After completion draw a graph or some visual and present to the class stating what the current population of your continent is and what are the major diseases plaguing the population of your continent.

Second Step: Now research the above by going back 100 years and has the population increased or decreased? What were the diseases back then? Are the disease today mostly environmentally induced or are they the same disease have evolved from one hundred years ago. Again after completion put a visual, a graph, poster presentation, power point together to present to the class.

Specific Suggestions:

None

Chapter 7 Objectives:

• • •

Define the population for a specific continent.

Define the disease of that population.

Describe the difference of population and disease from present time to one hundred years ago.

Chapter 7

Instructor Notes for In-Class Activity 4 Title:

Cataloging Toxins in the Home

Time: Materials: Handouts:

0 minutes prep; 15 - 25 minutes in class Internet access None

Procedures:

Have students catalog toxins found in their living environments, and discuss how well prepared they are to manage them.

Options: go on the internet to find “Material Safety Data Sheets” (MSDS’s) for these substances Have students check the lists they generate at home after they have returned to their homes.

• Were they fairly accurate?

• Did they omit entire classes of materials?

• Did they consistently omit the same types of substances?

Student Working in groups as assigned by your instructor, generate a list of toxic Instructions: substances you have in your home. It may be useful to do this by thinking room by room. If you live in a dorm, consider other toxic substances that you might come in contact with.

1. How well do you understand the potential effects of these substances 2. To what extent are you prepared to handle these materials, including cleanup after spills?

3. How many of these do you know how to dispose of properly?

Specific Suggestions:

None

Objectives:

Describe common but potentially toxic household materials and appropriate management practices.

Chapter 7

Answers to Critical Thinking and Review End of Chapter Questions: 1. What are the three leading causes of death in the United States? How are they related to lifestyle choices?

Ans: The three leading causes of death in the United States are cardiovascular diseases (of the heart and blood vessels), cancer, and chronic obstructive pulmonary disease (of the lungs); these diseases are noninfectious chronic health problems, and many are associated with aging. A significant fraction of premature deaths in the United States are caused in part by individual lifestyle habits involving poor diet, lack of exercise, and smoking.

2. Why are public health researchers concerned about “exporting” health problems associated with developed countries to less developed countries?

Ans: Research suggests that many unhealthy lifestyles associated with developed countries, including smoking, obesity and diabetes, are increasingly common in less developed countries.

As people in less developed countries adopt unhealthly lifestyles the rate of cardiovascular diseases (of the heart and blood vessels), cancer, and chronic obstructive pulmonary disease (of the lungs) increases.

3. What accounts for the much lower infant mortality rates in highly developed countries as compared to less developed countries?

Ans: Children in highly developed countries receive good healthcare, including vaccinations, and have sufficient nutrition for growth and development. In addition, the average woman in these countries gives birth to one or two children and during her pregnancies can eat well, rest when necessary, and receive medical attention as needed.

4. What was the first viral disease to be globally eradicated? What disease do health officials hope will be eradicated soon?

Ans: During the 20th century smallpox was eliminated worldwide. Health officials hope that polio will be eradicated soon.

5. What is a pandemic, and why does the potential for pandemics trouble many public health officials?

Ans: A pandemic is a disease that reaches nearly every part of the world, and has the potential to infect almost every person. A pandemic could kill millions or billions of people within a single year. In an era of global travel a virus could be spread around the world very quickly.

6. Distinguish among persistence, bioaccumulation, and biological magnification.

Ans: Chemicals that exhibit persistence are extremely stable and may take many years to be broken down into simpler forms by natural processes. Bioaccumulation is the buildup of a

Chapter 7 persistent toxic substance in an organism's body, often in the fatty tissues. Biological magnification is the increased concentration of toxic chemicals in the tissues of organisms that are at higher levels in food webs.

7. How do acute and chronic toxicity differ?

Ans: Acute toxicity is adverse effects that occur within a short period after exposure to a toxicant. Chronic toxicity is adverse effects that occur some time after exposure to a toxicant, or after extended exposure to the toxicant.

8. What is a dose-response curve? What can it tell us about effects at low doses if experimental information is on high doses?

Ans: A dose of a toxicant is the amount that enters the body of an exposed organism. A doseresponse curve shows the effect of different doses on a population. Typically, scientists first test the effects of high doses and then work their way down to a threshold level, the maximum dose with no measurable effect (or, alternatively, the minimum dose with a measurable effect). It is assumed that doses lower than the threshold level will not have an effect on the organism and are safe. However, if experimental information only exists for high doses the curve will not tell us how small doses effect a population.

9. Examine this cartoon criticizing cutbacks in pollution testing in the mid-1990s. What does the cartoon suggest about the relative value of toxicological information and epidemiological testing? Do you think this is a reasonable comparison? Explain your answer.

Ans: Answers will vary.

10. Describe the common methods for determining whether a chemical causes cancer.

Chapter 7 Ans: Toxicologists expose laboratory animals such as rats to varying doses of the chemical and see whether they develop cancer. Usually, two, three or four groups of animals are exposed to different amounts or doses, including a “control group” that is not exposed. At the end of the experiment (about two years for mice and rats), the animals are dissected, and the ratio of animals with tumors to animals without in each group is recorded. Epidemiologists look at historical exposures of humans to the same chemical, and see whether exposed groups show increased cancer rates. Ideally, a cohort or group of individuals who were exposed to the chemical are compared to an otherwise similar group who were not exposed.

11. Select one of the two choices to complete the following sentence, and then explain your choice: The absence of certainty about the health effects of an environmental pollutant (is/is not) synonymous with the absence of risk.

Ans: Answers will vary.

12. For each of the following scenarios, suggest whether it would be more appropriate to use cost-benefit analysis, the precautionary principle, or fractional risk attribution. Explain your answers. a. b. c. d. e.

Regulating risk associated with mercury from coal-fired power plants Compensating cancer patients who were exposed to chemicals on the job 20 years earlier Preparing for climate change-related illnesses in the year 2050 Creating a new policy for nanomaterials in cosmetics and medicines Preparing for diseases that might transfer from animals to humans in the future

Ans: A. Cost-benefit analysis. In a cost-benefit analysis, the estimate of some regulation to reduce risk is compared with potential benefits associated with that risk reduction.

B. Fractional risk attribution. Fractional risk attribution allocates the likelihood of each of two or more different possible causes.

C. Precautionary principle. When a new technology or chemical product is suspected of threatening health or the environment, precautionary measures should be undertaken even if there is uncertainty about the scope of the danger.

D. Precautionary principle E. Precautionary principle 13. How are risk assessments for human health and ecological risk assessments for environmental health alike? How do they differ?

Ans: Risk assessment involves using statistical methods to quantify the risks of a particular action so that they can be compared and contrasted with other risks. Like human health risk assessment, ecological risk assessment involves hazard identification, dose-response assessment, exposure assessment, and risk characterization. Human health risk assessment may look at the increased risk of developing cancer after exposure to contaminants in drinking water. In contrast

Chapter 7 ecological risk assessment works on a wide scale, from individual animals or plants in a local area to ecological communities across a large region.

14. Do you expect that a warmer world will improve or worsen human health? Explain your answer.

Ans: Answers will vary

Answers to Review Questions Human Health 1. What is the average life expectancy for a woman in Japan? A woman in Zambia?

Explain the difference.

The average life expectancy for a woman in Japan is 86. In contrast, the average life expectancy for a woman in Zambia is only 42. This health indicator (i.e., life expectancy), vividly demonstrates the contrasts in healthcare between highly developed countries and less developed countries; that is, the availability of quality healthcare, nutrition, and prenatal care.

2. How can a disease go from being emerging to being endemic in a population?

Emerging diseases are infectious diseases that were not previously found in humans; they typically jump from animal host to the human species. Endemic diseases are diseases that are constantly present in a population or region. AIDS is an example of an emerging disease that has become endemic. Epidemiologists think the HIV virus that causes AIDS jumped from nonhuman primates to humans as long ago as 100 years ago; but, has become widespread in only the last 30 years. To date, it has killed over 27 million people, and 34 million people currently live with the disease. AIDS is now known to be endemic in many regions in Africa.

Environmental Pollution and Disease 1. What are the differences among persistence, bioaccumulation, and biological magnification? How are these chemical characteristics interrelated?

Persistence is a characteristic of certain chemicals that are extremely stable and may take many years to break down into simpler forms through natural processes. Often times, persistent chemicals bioaccumulate (buildup) in an organism’s fatty tissues. If a persistent chemical bioaccumulates in the tissues of an organism that occupies a higher level in a food web, it is called biological magnification. This increased concentration of toxic chemicals, such as PCBs, heavy metals, and certain pesticides, in the tissues of an organism can be extremely harmful to its overall health.

Chapter 7

2. How did the 1980 chemical spill in Lake Apopka affect alligators?

In 1980, a chemical spill of DDT and other agricultural chemicals with estrogenic properties occurred in Lake Apopka, Florida. In the years following the spill, male alligators living in the lake exhibited low levels of testosterone and elevated levels of estrogen. Their reproductive organs were often feminized or abnormally small, and the mortality rate for eggs was extremely high.

Determining Health Effects of Environmental Pollution 1. What are toxicology and epidemiology, and how do they differ?

Toxicology studies the effects of toxic chemicals on human health, while epidemiology studies the effects of toxic chemicals and diseases on human populations. A toxicologist would most likely conduct a laboratory experiment to uncover a chemical’s toxic effects, while an epidemiologist might examine the historical exposures of humans to the same chemical in order to evaluate its toxicity. In general, epidemiology may be more representative than toxicology, but toxicology is usually more precise.

2. How are potentially toxic chemicals identified?

One way to determine the toxicity of a chemical is to administer various doses to populations of laboratory animals, measure the responses, and use the data to predict the chemical effects on humans. From this data a dose-response relationship could be created, and a threshold level for the respective chemical could be established.

3. Why are children particularly susceptible to environmental contaminants such as pesticides?

Children are more susceptible to most chemicals than are adults because their bodies are still developing and are not as effective in dealing with toxicants. Additionally, they weigh less than adults, so the same dose of a chemical can be more potent. More than half of all reports of exposure and possible poisoning from household pesticides involve children. These findings could be influenced by the fact that children tend to play on floors, and put items in their mouths more frequently than do adults.

Ecotoxicology: Toxicants Effects on Communities and Ecosystems 1. What environmental catastrophe was largely responsible for replacement of the dilution paradigm by the boomerang paradigm?

The discovery that the pesticide DDT was accumulating in birds at the top of the food web, and implications that DDT represented an unacceptable threat to ecosystem health and human health was largely responsible for replacement of the dilution paradigm by the boomerang paradigm.

Chapter 7

2. What is ecotoxicology?

Ecotoxicology is the study of contaminants in the biosphere, including their harmful effects on ecosystems. Ecotoxicology helps policymakers determine the costs and benefits of the many industrial and technological “advances” that affect humans and the ecosystems on which they depend.

Decision Making and Uncertainty: Assessment of Risks 1. What is risk assessment?

Risk assessment is the process of estimating the probability that a particular adverse effect will result from some exposure or condition, and the consequences of the particular adverse effect. Risk assessments, when properly performed, can provide information about the probability and severity of a risk or set of risks.

2. How does cost-benefit analysis differ from the precautionary principle?

In a cost-benefit analysis, the estimated cost of some regulation to reduce risk is compared with potential benefits associated with the risk reduction. It is an important mechanism to help decision makers formulate environmental legislation. The precautionary principle is the idea that no action should be taken or product introduced when the science is inconclusive and unknown risks may exist. The precautionary principle puts the burden of proof on the developers of the new technology or substance, who must demonstrate safety beyond a reasonable doubt. Advocates of cost-benefit analysis note that the precautionary principle may be extremely expensive or may cause us to hold off on new technologies that are much safer than those already in place.

3. When is an ecological risk assessment undertaken?

The Environmental Protection Agency and other federal and state environmental monitoring groups are increasingly trying to evaluate ecosystem health by using risk methods developed for assessing risks to human health. These ecological risk assessments estimate the ecological consequences of a range of human-induced stressors.

Ecological risk assessment is increasingly used to manage the diverse threats to watersheds.

Chapter 8 The Human Population Lecture Outline: A. The Science of Demography a. Demography-The applied branch of sociology that deals with population statistics and provides information on the populations of various countries or groups of people b. Current and future population Numbers i. World population has increased 82 million from 2009 to 2010 Not due to higher birth rate but to a lower death rate/higher life expectancy ii. Zero population growth-when the birth rate equals the death rate iii. Carrying capacity-The maximum number of individuals of a population that a particular environment can support for an indefinite period, assuming no changes in the environment iv. It is estimated the Earth can support a range from 4 billion to 16 billion v. Current population is about 6.0 billion vi. Human Migration 1. Has increased dramatically during the past few decades 2. Job searching, improving living standards, escape war or persecution all causes of migration 3. Deteriorating environmental conditions brought on my unsustainable population growth cause of migration 4. Not enough jobs in many countries’ economies to support population growth B. Demographic of Countries a. Highly developed countries have low rates of population growth, lowest birth rates and are highly industrialized relative to the rest of the world b. Highly developed countries have lowest infant mortality rate-the number of infant deaths under age 1 per 1000 live births c. Developing countries fall into 2 subcategories i. Moderately developed-Mexico, Turkey, Thailand 1. Infant mortality rates and birth rates are higher than highly developed countries but are declining ii. Less developed-Bangladesh, Niger, Laos, Ethiopia 1. Highest birth rates, highest infant mortality rates, and shortest life expectancy d. Replacement-level Fertility-The number of children a couple must produce to “replace” them. e. Total Fertility Rate-The average number of children born per woman, given the populations birth rate f. Demographic Stages i. Preindustrial Stage-birth and death rates were high, population grows at a modest rate

Chapter 8 ii. Transitional Stage-lowered death rate, rapid growth rate due to high birth rate iii. Industrial Stage-decline in birth rate, slower growth rate, relatively low death rate iv. Postindustrial Stage-low birth and death rates due to improved living standards g. Population growth momentum-The potential for future increases or decreases in a population based on the present age structure h. Aging population-higher percentage of people who are chronically ill or disabled, require more health care and social services i. Produce less wealth increasing a countries tax burden, strains social security, health and pension plans C. Population and Quality of Life a. Sustainability of the 9.15 billion population projected for the year 2050 is unknown b. Population and Chronic Hunger i. Food security-condition in which people do not live in hunger or in fear of starvation. ii. Food insecurity-condition in which people live with chronic hunger and malnutrition iii. Economic development-an expansion in a governments economy, viewed by many as the best way to raise standards of living 1. Politicians and economists view as the best way to tackle the worlds food problems D. Reducing the Total Fertility Rate a. Culture and Fertility i. Culture-the ideas and customs of a group of people at a given period; culture which is passed on from generation to generation, evolves over time ii. High total fertility rates are tradition in many cultures iii. For a society to endure it must produce enough children who can survive to reproductive age b. The Social and Economic Status of Women i. Gender Inequality-The social construct that results in women not having the same opportunities or privileges as men/exists in most societies ii. In most countries women are not guaranteed equality in legal rights, education, employment and earnings or political participation iii. Gender Parity-in education is the right of every child boy or girl to attend school-181 countries currently participate iv. Laws, customs and lack of education often limit women to low-skilled, low-paying jobs c. Marriage Age and Fertility i. Generally there is a correlation between marriage age and total fertility i.e.: In Pakistan the average age of marriage is 17 and the total fertility rate is 4.0. In Denmark the average age of marriage is 30 and the total fertility rate is 1.8.

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Chapter 8 ii. Education increases a women’s options and decrease total fertility rate d. Family Planning Services i. Services that enable men and women to limit family size, safeguard individual health rights, and improve the quality of life for themselves and their children ii. Provide information on reproductive physiology and contraceptive use iii. Contraceptive use is strongly linked to lower total fertility rates E. Government Policies and Fertility a. In recent years the governments of at least 78 developing countries have prioritized population growth i. Sponsoring family planning projects b. China and Mexico: Contrasting Population Growth Measures i. China has largest population in the world 1. Introduces aggressive plan to lower population-offered incentives to couples having only one child per family 2. Births dropped from 5.8 births per woman in 1970 to 2.1 births per woman in 1981 3. Plan was controversial because it compromised individual freedom of choice ii. Mexico was traditionally a pro-population growth government.

1. In the 1960s government became alarmed at fast rate of population growth 2. Introduced educational reform, family planning and healthcare programs 3. Birth rates reduced from 6.7 births per woman in 1970 to 2.2 births per woman in 2010 F. Millennium Development Goals a. Eradicate extreme hunger and poverty b. Achieve universal primary education c. Promote gender equality and empower women d. Reduce child mortality e. Improve maternal health f. Combat HIV/AIDS, malaria and other diseases g. Ensure environmental sustainability h. Develop a global partnership for economic development G. Achieving Population Stabilization a. Developing countries should increase the amount money allotted to public health and family planning services b. Governments should take steps to increase the average level of education, especially of women and women must be given more employment opportunities c. Highly developed nations should face their own population problems, unsustainable consumptions by affluent people and increase the reuse and recycling of materials

Chapter 8

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Did Malthus Get it Wrong?

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: Malthus’ Predictions about human population growth will prove correct in the next two decades.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions:

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Chapter 8 Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Identify Thomas Malthus, relate his ideas on human population growth, and explain why he may or may not be wrong.

Chapter 8

Instructor Notes for In-Class Activity 2 Title:

Household Pets, Household Pests

Time: Materials: Handouts:

0 minutes prep; 10 – 20 minutes in class None None

Procedures:

Have students make lists of the most common household pets and pests.

For each, have them list the characteristics that make them attractive or distasteful to their human hosts.

Then, as a class, discuss: Are pets or pests more likely to be K strategists? Is this universally true?

Is a relationship between reproductive strategy and the pet-human / pesthuman relationship.

Student Make a list of the most common household pets and household pests.

Instructions: For each, list the characteristics that make them attractive or distasteful to their human hosts.

Specific Suggestions:

None

Objectives:

• •

Differentiate between K- and r-strategists.

Describe density dependent and density independent influence on population growth.

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Chapter 8

Instructor Notes for In-Class Activity 3 Title:

Demographic Transition Model and Determinism

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: The demographic transition model is deterministic, so government sponsored population control measures are not necessary to limit human population growth.

(See figure 8.14) Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 4. Which, if either, provided the most credible INFORMATION 5. Which provided the most compelling overall argument.

6. Be sure students argue their points forcefully, whether or not they believe them personally.

Chapter 8 Student See above Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 3. Do not allow personal assaults 4. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

• •

Explain how highly developed and developing countries differ in population characteristics such as infant mortality rate, total fertility rate and age structure.

Describe the Demographic Transition Model.

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Chapter 8

Instructor Notes for In-Class Activity 4 Title:

Changes in Population

Time: Materials: Handouts:

5 minutes prep; 60 minutes out of class time None None

Procedures:

In chapter 7 the students were assigned continents to see what is the population of that continent or islands. Now have the students take the same continent or island and bread down the population in to adult, infant or child, senior citizen and also into culture or race. It will be interesting for each group to define what they think is an adult, infant, or senior citizen. Have them make a collage of their continent with the faces of pictures cut out of magazines portraying their continent. Questions they could research is: how many births in the last 100 years? What is the mean age of the continent? What is the average income? What is the ratio between men and women, senior citizens and children etc. Have the students put all their facts on a graph and present to the class.

Student Using the continent you were assigned in chapter 7, break down the Instructions: population in to ages, race, male/female etc. Present your data to the class in the form of a graph.

Specific Suggestions:

None

Objectives:

• •

Define population and diversity.

Describe the population on a specific continent or island.

Chapter 8

Answers to Critical Thinking and Review End of Chapter Questions: 1. What are some of the factors that have contributed to the huge increase in the incidence of AIDS in sub-Saharan Africa?

Ans: People in sub-Saharan Africa have little access to prevention information; knowledge about how the virus is spread and how to protect oneself must reach at-risk populations. People in this region also have little access to effective treatment, such as anti-retroviral drugs.

2. What is demography?

Ans: Demography is the applied branch of sociology that deals with population statistics and provides information on the populations of various countries or groups of people.

3. What was the human population when you were born? When your parents were born?

Ans: Answers will vary.

4. Some people suggest that Malthus’s ideas about human population growth outrunning the environment’s ability to support it could happen on a global level. How might this happen in developing countries? In highly developed countries?

Ans: Answers will vary but should include.

Developing countries: Applying Malthus’s principles to developing countries would suggest that food production will not keep pace with population growth and developing countries will experience food shortages with increases chances of wars erupting over food supplies.

Highly developed countries: Highly developed countries will probably not suffer from food shortages since their populations are not growing at a rapid pace. Instead highly developed countries might see a reduction in their standard of living as other finite resources become scarce and the price of those resources and material increase dramatically.

5. Why is it so difficult to apply the biological concept of carrying capacity directly to the human population?

Ans: It is difficult to apply the concept of carrying capacity directly to humans because humans have the ability to alter the environments in which they live. Additionally the improvements and increases in food production, medicine, etc. can significantly impact carrying capacity. Humans have the ability to live in almost any environment on Earth.

6. What are total fertility rate and infant mortality rate? Which group of countries has the highest total fertility rates? Which group has the highest infant mortality rates?

Ans:

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Chapter 8 Infant mortality rate is the number of infant deaths (under age 1) per 1000 live births.

Highly developed countries have low infant mortality rates. Moderately developed countries have infant mortality rates that are higher than those of highly developed countries, but they are declining. Less developed countries have the highest infant mortality rates.

Total fertility rate is the average number of children born to each woman. Less developed countries have high total fertility rates compared low rates in highly developed counties.

7. Which population is more likely to have a positive population growth momentum? Which is more likely to have a negative population growth momentum? Explain your answers?

Ans: Age structure A has the largest group of individuals in the prereproductive group (0-14 years) and will have the fastest population growth among the three. The last age structure C (smallest prereproductive group) is the one most likely to experience negative population growth since it’s prereproductive group is smaller than the group it will be replacing.

8. How is carrying capacity of the Earth system related to land degradation and agricultural productivity?

Ans: In this chapter we have learned that carrying capacity is the maximum number of individuals of a given species that a particular environment can support for an indefinite period, assuming there are no changes in the environment. If, however; the environment changes (or technology changes) and agricultural productivity is increased then the carrying capacity for that environment will increase. The opposite is also true, it agricultural productivity declines then the carrying capacity will decline in that environment.

9. What is food insecurity? What regions of the world have the greatest food insecurity?

Ans: Food insecurity is the condition in which people live with chronic hunger and malnutrition. . South Asia and sub-Saharan Africa are the two regions of the world with the greatest food insecurity.

10. How are population growth and economic development related?

Ans: As economic development increases population growth normally decreases.

11. How do cultural values affect fertility rate?

Ans: A society's culture exerts a powerful influence over individuals by controlling their behaviors With respect to fertility and culture, a couple is expected to have the number of children determined by the cultural traditions of their society. Having large families change

Chapter 8 traditional values may take longer than expected. Religious values are another aspect of culture that affects total fertility rates. Different religions place different values on family size.

12. This photograph shows Nigerian students in a classroom. Why do you think the school has many more boys than girls? How is fertility rate related to educational opportunities for women?

Ans: Answers will vary but should include: cultural/traditional values or roles for boys versus girls, education opportunities for boys versus girls, value placed on boys versus girls. It has been shown repeatedly that the more education opportunities for girls the lower the fertility rate will be.

13. What is family planning? Is family planning effective in reducing fertility rates?

Ans: Family planning services are services that enable men and women to limit family size, safeguard individual health rights, and improve the quality of life for themselves and their children. The governments of most countries recognize the importance of educating people about basic maternal and child health care. Developing countries have had success in significantly lowering total fertility rates, and credit many of these results to effective family planning programs.

14. Health experts are concerned that the surplus of men in China will lead to an increase in AIDS, particularly in cities. Explain the link.

Ans: Demographers estimate that by the mid 21st century, marriageable males will outnumber marriageable females by 1 million. If men that are concentrated in cities are not able to marry they may visit prostitutes. If safe sex practices are not followed the rate of HIV/AIDS transmission could increase rapidly among this group.

15. Why does Mexico have a positive population growth momentum?

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Chapter 8

Ans: Even with a low birth rate, positive population growth momentum will cause the population to continue to increase in the future because of the large number of young women having babies.

Mexico has a tremendous potential for growth because 32% of its population is less than 15 years of age.

16. What are four Millennium Development Goals that the nations of the world have aspired to?

What is the target date for these goals?

Ans: Any four of the following goals. The target date is 2015.

Goal 1: Eradicate extreme hunger and poverty.

Goal 2: Achieve universal primary education. All boys and girls, regardless of where they live, should enroll in and complete a primary education (grades 1 through 5).

Goal 3: Promote gender equality and empower women. This goal is also based on education—by 2015, gender disparity should be eliminated in all levels of education.

Goal 4: Reduce child mortality. The target is to reduce the mortality rate of infants and children under five years of age by two-thirds.

Goal 5: Improve maternal health. By 2015, the maternal mortality ratio should be reduced by two-thirds.

Goal 6: Combat HIV/AIDS, malaria, and other diseases.

Goal 7: Ensure environmental sustainability. This is a multi-part goal that includes reversing the loss of natural resources, halving the number of people without sustainable access to safe drinking water and basic sanitation, and improving the lives of at least 100 million people living in slums.

Goal 8: Develop a global partnership for development. The financial aspects of the MDGs are encompassed in this goal. Among the seven targets are providing measures for debt relief for the external debts in developing countries, creating productive jobs for young people, and providing access to affordable medicines in developing countries.

17. What is voluntary simplicity? How is it related to resource consumption?

Ans: Voluntary simplicity is a way of life that involves wanting and spending less. Individual efforts to reduce material consumption are effective for their collective effects and because they may influence additional people to reduce unnecessary consumption. Voluntary simplicity involves desiring less of what money can buy. Each person who scales back his or her consumption benefits the environment.

18. Discuss this statement: The current human population crisis causes or exacerbates all environmental problems, including energy issues and climate change.

Ans: As our numbers increase during the 21st century, environmental degradation, hunger, persistent poverty, economic stagnation, urban deterioration, and health issues will continue to challenge us. Already the need for food for the increasing numbers of people living in environmentally fragile arid lands, such as parts of sub-Saharan Africa, has led to overuse of the land for grazing and crop production. The need to grow more food and to build more houses for a growing population leads to habitat destruction for potential endangered and threatened

Chapter 8 species. A larger population consumes more energy which leads to more pollution and carbon emissions which have been linked to climate change. Increases in population will lead to an increase in environmental problems.

Answers to Review Questions The Science of Demography 1. Describe human population growth for the past 200 years.

Up until the 1800’s, it had taken thousands of years for the human population to reach 1 billion. Since 1800, it took only 130 years for the population to reach 2 billion (in 1930), 30 years for the population to reach 3 billion (in 1960), 15 years to reach 4 billion (in 1975), 12 years to reach 5 billion (in 1987), and 12 years to reach 6 billion (1999). In general, human population growth has exponentially increased over the past 200 years.

2. Who was Thomas Malthus, and what were his views on human population growth?

Thomas Malthus was a 19th-century British economist who pointed out that the human population can increase faster than its food supply, and that such an increase would most likely result in famine, disease, and war.

3. When determining Earth’s carrying capacity for humans, why is it not enough to just consider human numbers? What else must be considered?

Carrying capacity is the maximum number of individuals of a given species that a particular environment can support for an indefinite period, assuming there are no changes in the environment. However, when considering the carrying capacity for humans, one must also consider standard of living, resource consumption, technological innovations, and waste generation.

Demographics of Countries 1. What is infant mortality rate? Why do highly developed countries have low infant mortality rates?

Infant mortality rate is the number of infant deaths (under age 1) per 1000 live births.

Highly developed countries tend to have low infant mortality rates due to medical advances and availability of quality healthcare.

2. What is population growth momentum?

Population growth momentum is the potential for future increases or decreases in a population based on the present age structure.

Population and Quality of Life

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Chapter 8 1. How is agricultural productivity related to carrying capacity?

Agricultural productivity is one of many factors positively correlated with the global carrying capacity for humans. Likewise, when land overuse occurs, often in combination with an extended drought, formerly productive lands may decline in agricultural productivity – that is, their carrying capacity may decrease.

2. How is human population growth related to chronic hunger?

One of the many causes of chronic hunger is insufficient food to feed all the world’s peoples. Unfortunately, chronic hunger has been exacerbated by the rapid increase in human population growth over the last 200 years.

3. How is human population growth related to economic development?

Economic development is an expansion in a government’s economy, viewed by many as the best way to raise the standard of living. Most economists think that slowing population growth promotes economic development.

Reducing the Total Fertility Rate 1. How are high total fertility rates related to the economic roles of children in certain cultures?

Higher total fertility rates in some developing countries are due to the important economic and societal roles of children. For example, in some societies, children usually work in family enterprises such as farming or commerce, contributing to the family’s livelihood. Additionally, when these children become adults, they provide for their aging parents. Worldwide, nearly 176 million children between the ages of 5 and 14 work fulltime; of these, 53 million do hazardous work, such as mining and construction.

2. What appears to be the single most important factor affecting high TFRs? The single most important factor affecting high total fertility rates is the low status of women in many societies.

3. How do family planning services influence TFR? Family planning services are services that enable men and women to limit family size, safeguard individual health rights, and improve quality of life for themselves and their children. Total fertility rates tend to decrease where family planning services are available.

Government Policies and Fertility

Chapter 8 1. What are the successes and failures of China and Mexico in slowing human population growth?

China: In 1971, China began to pursue the goal of reducing its national total fertility rate.

It began by urging couples to marry later, increase spacing between children, and limit the number of children to two. However, this was not enough. Then, in 1979, China began a coercive one-child family policy to reduce total fertility rate. They began providing incentives in the form of medical care, schooling, cash bonuses, preferential housing, and retirement funds to promote later marriages, and one-child families. While this plan brought about the most rapid and drastic reduction in fertility in the world (i.e., from 5.8 births per woman in 1970 to 2.1 in 1981), it was controversial and unpopular because it compromised individual freedom of choice. Moreover, it is suspected that many expectant parents aborted female fetuses or killed or abandoned newborn baby girls as sons are valued more highly than daughters in the Chinese culture. The program is now relaxed throughout rural China; education and publicity campaigns are used today.

Mexico: Traditionally, the Mexican government supported rapid population growth, but in the late 1960s the government became alarmed at how rapidly the population was increasing. In 1974, the Mexican government instigated several measures to reduce population growth, such as educational reform, family planning, and healthcare. Mexico has had great success in reducing its fertility level, from 6.7 births per woman in 1970 to 2.2 births in 2010. However, Mexico still has a tremendous potential for growth because 29% of its population is less than 15 years of age. Even with a low birth rate, positive growth momentum will cause the population to continue to increase in the future because of the large number of young women having babies. Mexico’s recent efforts at population control include multimedia campaigns.

2. What is population growth momentum?

Population growth momentum is the potential for future increases or decreases in a population based on the present age structure.

3. What are the Millennium Development Goals?

The U.N. Millennium Summit formed a global partnership with a plan of action, known as the Millennium Development Goals. The goals are to eradicate extreme hunger and poverty; achieve universal primary education; promote gender equality and empower women; reduce child mortality; improve maternal health; combat HIV/AIDS, malaria, and other diseases; ensure environmental mental sustainability; and develop a global partnership for economic development.

Achieving Population Stabilization 1. How does voluntary simplicity mitigate the effects of population growth?

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Chapter 8 Voluntary simplicity is a way of life that involves wanting and spending less. Each person who scales back upon unnecessary consumption lessens the effects of population growth.

Chapter 9 The Urban Environment Lecture Outline: I. Population and Urbanization A. Urbanization is the process in which people increasingly move from rural areas to densely populated cities i.

Cities have traditionally provided more jobs because cities are the sites of industry, economic development, educational and cultural opportunities, and technology advancements – all of which generate income ii. The continued rapid growth of cities has the potential to cause additional human suffering and poverty as well as environmental problems B. The geographic distribution of people in rural areas, town, and cities significant influences the social, environmental, and economic aspects of population growth C. Characteristics of the urban population i.

There is usually far greater heterogeneity with respect to race, ethnicity, religion, and socioeconomic status in urban areas ii. Urban areas are generally younger due to the influx of many young adults from rural areas iii. Cities in developing nations tend to have more males; cities in highly developed countries often have a higher ratio of females to males D. Urbanization trends i.

48% of the world population currently lives in urban areas ii. Urbanization is increasing rapidly in developing countries 1. Almost 400 cities worldwide have a population of at least one million inhabitants, and 284 of these cities are in developing countries 2. Megacities are cities with more than 10 million inhabitants; in 2005 eight of the 10 world’s largest cities were in developing countries iii. Urban agglomerations are urbanized core regions that consist of several adjacent cities or megacities and their surrounding developed suburbs (for example, Tokyo-Yokohama-Osaka-Kobe agglomeration in Japan is home to nearly 50 million people) iv.

The recent fast paced urban growth in developing countries has outstripped the limited capacity of many cities to provide basic services 1. Challenges include poverty, high unemployment, heavy pollution, and inadequate (nonexistent) water, sewage, and waste disposal 2. Rapid urban growth strains schools, medical, and transportation systems II. The City as an Ecosystem A. Urban ecologists study urban trends and patterns in the context of four variables (POET); these four variables doe not function independently of one another: i.

Population – number of people, factors that change this number, and composition of the city by age, sex, and ethnicity

Chapter 9 Organization – social structure of the city, including its economic policies, method of government, and social hierarchy iii. Environment – considers both the natural environment and the city’s infrastructure (road, bridges, buildings); also, environmental changes caused by humans (air and water pollution) iv.

Technology – human inventions that directly affect the urban environment (aqueducts, air conditioning) B. Phoenix, Arizona: long-term study of an urban ecosystem i.

Long-Term Ecological Research (LTER) sites gather extensive data on various ecosystems ii. Knowledge gained in urban ecology could increase public awareness and eventually influence policy decisions C. Environmental problems associated with urban areas i.

Growing urban areas affect land use patterns and destroy or fragment wildlife habitat by suburban development 1. Brownfields are urban areas of abandoned, vacant factories, warehouses, and residential sites that may be contaminated from past use 2. Reuse of brownfields is complicated due to environmental contamination ii. Cities affect water flow by covering the rainfall-absorbing soil with buildings and paved roads iii. Heavy dependence on motor vehicles increases air pollution and causes other environmental problems iv.

Urban heat islands are created by local heat buildup in areas of high population density 1. They affect local air currents and weather conditions, particularly by increasing number of thunderstorms 2. They also contribute to the buildup of pollutants, especially particulate matter, in the form of dust domes v.

Sound is called noise pollution when it becomes loud or disagreeable, resulting in physiological or psychological harm D. Environmental benefits of urbanization i.

A solution to urban growth is compact development, which uses land efficiently ii. Public transportation is an important part of compact development III. Urban Land Use Planning A. Land use in many cities is based on economic concerns (i.e., taxes, income, etc.) i.

Land use planning is the process of deciding the best uses for undeveloped land in a given area ii. Economic institutions, such as banks and multinational corporations, influence land use in cities iii. Cities regulate land use mainly through zoning, in which the city is divided into use zones B. Transportation and urban development ii.

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Transportation and land use are inextricably linked because as cities grow, they expand along public transportation routes ii. Many people live in suburbs far from their place of employment, and daily commutes of 20 miles or more each way are commonplace C. Suburban sprawl i.

Suburban sprawl is defined as a patchwork of vacant and developed tracts around the edges of cities, typically low in population density 1. This pattern of land use has increased the economic disparity between older neighborhoods and newer suburbs 2. U.S. voters have grown increasingly concerned about the unrestricted growth of suburban sprawl ii. Smart growth is an urban planning and transportation strategy that mixes land uses (commercial, manufacturing, entertainment, and a range of housing types) IV. Making Cities More Sustainable A. A city with a livable environment, a strong economy, and a social and cultural sense of community is known as a sustainable city B. Sustainable cities enhance the well-being of current and future generations of urban dwellers

Chapter 9

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Designing a City

Time: Materials: Handouts:

10 minutes prep; One class period (at least) None Yes

Procedures:

Suppose the Chinese Government has decided to create a new “model city” to be open by the 2008 Olympics. They would like it to have 3 – 5 million people by 2010. It will serve as a port city, a center for tourism, and (they expect) will house high tech / telecommunications industry.

The Chinese government would like reasonable access to energy, clean air and safe water, adequate housing.

Keep in mind: “New China” is a difficult mix of public and private. They do NOT want the city to grow at the whims of the private sector, turning into sprawl, urban center decay, etc. But at the same time, they recognize that there will be income disparities and powerful market forces. They are, therefore, willing to invest in initial infrastructure, but would like a “self-sustaining” design. If you over-plan, the infrastructure may cost too much; households, for example, may be hooked to the electrical grid but unable to afford electrical rates! If you under-plan, the city may grow into a mighty chaos.

Big picture items: • What services / infrastructure does this city need? (Exhaustive list) • How will it get these, and who will provide them? (Which should be central, which could be supplied through markets, which will require a combination).

More focus: • What are some options for the physical design of this city. How might you limit, for example, transportation energy usage or emissions?

• Would it be best to grow outward or upward? Should there be one city center or multiple city centers? How will people from outside get to the city?

Student Working in groups of 3-4, design a city as described in the worksheet Instructions: After you have created your city, have one of your members report your findings to the class.

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Specific Suggestions:

None

Objectives:

• •

Discuss the use of zoning in land use planning Define compact development

Chapter 9 Assignment One Handout (Worksheet) Suppose the Chinese Government has decided to create a new “model city” to be open by the 2008 Olympics. They would like it to have 3 – 5 million people by 2010. It will serve as a port city, a center for tourism, and (they expect) will house high tech / telecommunications industry.

The Chinese government would like reasonable access to energy, clean air and safe water, adequate housing.

Keep in mind: “New China” is a difficult mix of public and private. They do NOT want the city to grow at the whims of the private sector, turning into sprawl, urban center decay, etc. But at the same time, they recognize that there will be income disparities and powerful market forces. They are, therefore, willing to invest in initial infrastructure, but would like a “self-sustaining” design.

If you over-plan, the infrastructure may cost too much; households, for example, may be hooked to the electrical grid but unable to afford electrical rates! If you under-plan, the city may grow into a mighty chaos.

Big picture items: • What services / infrastructure does this city need? (Exhaustive list) • How will it get these, and who will provide them? (Which should be central, which could be supplied through markets, which will require a combination).

• What are some options for the physical design of this city? How might you limit, for example, transportation energy usage or emissions?

• Would it be best to grow outward or upward? Should there be one city center or multiple city centers? How will people from outside get to the city?

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Instructor Notes for In-Class Activity 2 Title:

Riding Public Transit

Time: Materials: Handouts:

0 minutes prep; 15 – 20 minutes in class None None

Procedures:

Ask for a show of hands for those students who ride public transit locally, and who have taken public transit in other locations. Have them write down: • What factors would make them more willing to ride on busses, subways, or other forms of transit?

• What factors would make them less willing?

• Where does public transit work well? Why? Give examples.

• Where does public transit not work well? Why? Use this information to discuss the interactions between urbanization, population density, and opportunities to reduce impact.

Student Instructions:

Also, use this as an opportunity to revisit the IPAT model.

• How does using public transit fit in the model?

• Does riding public transit represent a change in affluence?

Explain.

• Does public transit represent a Technological difference? Again, explain and discuss.

See above

Specific Suggestions:

An alternative, depending on your location, would be to assign students to ride on public transit, or even have the class ride local public transit as a field trip.

Objectives:

Relate how a city’s transportation infrastructure affects urban development.

Chapter 9

Instructor Notes for In-Class Activity 3 Title:

Homelessness and the Urban Environment

Time: Materials: Handouts: Procedures:

5 – 15 minutes prep; 15 – 30 minutes in class Internet access None Have students

Student The homeless in America’s urban areas interact with their environments Instructions: in substantially different ways than do people with homes.

Spend some time researching the number of homeless in your areas, or in a nearby urban area.

Generate a list of interactions between the homeless and their environment that differ from those of people who have homes. Think of this in terms of “niches” (keep in mind that all organisms, including all humans, occupy niches. That is to say, what is their physical environment, where do they obtain food, what happens to their wastes?

Consider the implications of these interactions on the urban environment.

Do the homeless have a larger or smaller impact on the urban environment than do others? What about the broader environment that supports an urban area?

Specific Suggestions:

Be sure not to let students make stereotypical assumptions about the homeless. This can be an extremely sensitive issue, especially since some students may know homeless, or may be homeless themselves.

Objectives:

• • •

Explain how human interactions with their environments can be described in ecological terms.

Describe some of the problems associated with the rapid growth of large urban areas.

Describe the factors that contribute to an organism’s ecological niche.

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Instructor Notes for In-Class Activity 4 Title:

Sustainable Cities

Time: Materials: Handouts:

5 minutes prep; 60 minutes out side of class None None

Procedures:

This is a two-part activity. The first part of this activity is to assign students working individually or in groups of two or three to research cities around the world. The choices might be Hong Kong, Sidney, London, Toyko, Moscow also cities that are much smaller like Waco, Texas, Bloomington, Illinois, Madison, Wisc. Etc. It would even be fun if the students chose their own city or the city they were born. There should be at least 10 or 15 different cities all over the world. After the selection for the cities has been made have the students research their city for the problems the city is having which may include health problems, financial problems, crime rate, housing, also look for solutions to the problems, the benefits for living in that city for example location, view, climate, natural resources etc. Then look at the downfalls of the city which may also include climate, natural resources etc. Each city should have a profile, from the population, natural resources, health issues, financial stability etc. Then let the students report their findings to the class.

The second part of this activity is for the students to build a monopoly type of game using the information gathered from the above part one assignment.

Student Part 1 Instructions: Pick a city from the list of cities available and research the benefits and problems this city has or is facing. Some of the issues would be health issues, natural resources, financial stability, crime, over population, climate, location, standard of living, jobs available, general environmental issues etc.

After you have completed your research report to the class.

Part 2 Compile all the information from the class and use an old monopoly board and re-title the board to fit the cities you have researched. For the chance cards, use the problems you encountered in your research study and for the community chest cards you can put the benefits. Use money stock, environmental coins for the good environmental issues and establish laws and penalties when going around the boards. You could mix monopoly, cutes and ladders, sorry, trivia or other games to center around the sustainability of the cities involved. Be creative and have fun.

Chapter 9 Specific Suggestions:

Do not tell the students they will be collectively building a monopoly game until after part one of these assignments is over. This will have the students take the information gathered and apply it and if they have to go back to the research they may do so, but this way the students might realize what other information is needed.

Objectives:

• •

List at least five characteristics of an ideal sustainable city Define suburban sprawl and discuss a problem caused or exacerbated by sprawl.

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Answers to Thinking About the Environment End of Chapter Questions: 1. Which countries are the most urbanized? The least urbanized? What is the urbanization trend today in largely rural nations?

Ans: The percentage of people living in cities compared with rural settings currently is greater in highly developed countries than in developing countries. In 2006, urban inhabitants comprised 77% of the total population of highly developed countries but only 41% of the total population of developing countries. Currently, most urban growth in the world is occurring in developing countries, whereas highly developed countries are experiencing little urban growth 2. Generally, the higher a country's level of urbanization, the lower its level of poverty. Suggest a possible explanation for this observation.

Ans: Answers will vary 3. What is an urban agglomeration? Give an example.

Ans: Urban agglomeration is an urbanized core region that consists of several adjacent cities or megacities and their surrounding developed suburbs. An example is the Tokyo-YokohamaOsaka-Kobe agglomeration in Japan, which is home to about 50 million people.

4. Why are the U.S. urban agglomerations shown in Figure 9.3 each considered a functional system?

Ans: The flow of goods and services within each agglomeration links the entire area into a single functional system.

5. What are some of the problems brought on by rapid urban growth in developing countries?

Chapter 9 Ans: Cities in developing nations generally face more serious challenges than cities in highly developed countries. These challenges include poverty; exceptionally high unemployment; heavy pollution; and inadequate or nonexistent water, sewage, and waste disposal. Rapid urban growth strains school, medical, and transportation systems.

6. Suggest a reason why many squatter settlements are built on floodplains or steep slopes.

Ans: Land that is not desirable to developers may be claimed as temporary shelter for the poorest member of society.

7. What are the four variables that urban ecologists study?

Ans: Urban ecologists study urban trends and patterns in the context of four variables: population, organization, environment, and technology. Population refers to the number of people; the factors that change this number (births, deaths, immigration, and emigration); and the composition of the city by age, sex, and ethnicity. Organization is the social structure of the city, including its economic policies, method of government, and social hierarchy. Environment considers both the natural environment, such as if the city is situated near a river or in a desert, and the city's physical infrastructure, including its roads, bridges, and buildings. Technology refers to human inventions that directly affect the urban environment.

8. What is a brownfield? Why is it challenging to redevelop brownfields?

Ans: A brownfield is an urban area of abandoned, vacant factories, warehouses, and residential sites that may be contaminated from past uses. The biggest challenge to the redevelopment of brownfields is the environmental contaminates that must be cleaned up before redevelopment can proceed.

9. What is an urban heat island? A dust dome?

Ans: An urban heat island is a local heat buildup in an area of high population density. A dust dome is a dome of heated air that surrounds an urban area and contains a lot of air pollution.

10. How can land use planning promote compact development?

Ans: Land use planning is the process of deciding the best uses for undeveloped land in a given area. Cities regulate land use mainly through zoning, in which the city is divided into use zones, areas restricted to specific land uses, such as commercial, residential, or industrial. Property owners can develop their properties as long as they meet the zoning ordinances in which the property is located. Often these rules are very specific, regulating building height, how the building is situated on the property, and what the property can be used for. Zoning has largely resulted in separate industrial parks, shopping centers, apartment districts, and the like. By separating areas where people work, shop and live people need to travel further distances. If compact development is a goal, areas need to be zoned to contain all aspects of daily life or easily linked by public transportation.

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Chapter 9 11. Why is good governance so important in increasing sustainability in cities?

Ans: Cities do not exist as separate entities; they are part of larger political organizations, including counties, states or provinces, and countries, all of which affect urban development.

Economic institutions, such as banks and multinational corporations, also influence land use in cities. If policy makers make good planning decisions, cities can become more sustainable.

According to social scientists, the most effective urban, regional, and national governments are democratic and participatory, in which local citizens are encouraged to work together to address local problems.

12. Examine the cartoon. What point is the cartoonist making?

Ans: Answers may vary.

13. How has transportation affected the spatial structure of cities?

Ans: Transportation and land use are inextricably linked because as cities grow, they expand along public transportation routes. The kinds of transportation available at a particular period in history affect a city's spatial structure. During the 1700s to the 1850s, transportation in the city was limited to walking, horse-drawn carriages, and ships. Technological advances enabled fixed transportation routes (railroads and electric street trolleys) to spread out of the city from the central business district during the 1870s to 1910s. People could move beyond the city limits quickly and inexpensively. Even though the first suburbs clustered around railway stations, the city was relatively contained. An example, the average commute was only about 1.5 miles in the 1920s. Cars and trucks forever changed the city, increasing its spatial scale. With the advent of the automobile era during the 20th century, roads expanded the access to undeveloped areas between the “arms” of prior metropolitan development, filling in the wild spaces. Construction of the interstate highway system and outer-city beltway “loops,” beginning in the 1950s, encouraged development even farther from the city's central business district. Today, many people live in suburbs far from their place of employment, and daily commutes of 20 or more miles each way are commonplace.

Chapter 9 14. How has Curitiba, Brazil, been designed to incorporate sustainability?

Ans: The city developed an inexpensive, efficient mass transit system that uses clean, modern buses that run in high-speed bus lanes. High-density development was largely restricted to areas along the bus lines, encouraging population growth where public transportation was already available. Curitiba was the first city in Brazil to use a special low-polluting fuel that contains a mixture of diesel fuel, alcohol, and soybean extract. In addition to burning cleanly, this fuel provides economic benefits for people in rural areas who grow the soybeans and grain (used to make the alcohol). Over several decades, Curitiba purchased and converted flood-prone properties along rivers in the city to a series of interconnected parks crisscrossed by bicycle paths. Another example of Curitiba's creativity is its labor-intensive Garbage Purchase program, in which poor people exchange filled garbage bags for bus tokens, surplus food (eggs, butter, rice, and beans), or school notebooks.

15. The following graph shows projected CO2 emissions in India based on the level of urbanization that occurs in the 21st century. Why do you think a higher level of urbanization will result in greater CO2 emissions? How might India reduce its CO2 emissions without reducing its energy consumption (which is necessary as India develops economically)?

Ans: Answers may vary.

Answer to Review Questions Population and Urbanization 1. What is urbanization? What parts of the world have the fastest current rates of urbanization?

Urbanization is the process in which people increasingly move from rural areas to densely populated cities. Typically, as a nation develops economically, the proportion of the population living in cities increases. Consequently, the fastest current rates of urbanization are occurring in developing countries.

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2. What is a megacity? An urban agglomeration?

Megacities are cities with more than 10 million inhabitants. In some places, separate urban areas have merged into an urban agglomeration. Urban agglomerations are urbanized core regions that consist of several adjacent cities or megacities and their surrounding developed suburbs.

3. What are some of the problems encountered when large urban areas experience rapid growth?

Rapid urban growth often outstrips the capacity of cities to provide basic services.

Challenges include substandard housing; poverty; high unemployment; pollution; and inadequate or nonexistent water, sewage, and waste disposal. Rapid urban growth also strains school, medical, and transportation systems.

The City as an Ecosystem 1. How is a city system analyzed from an ecosystem perspective?

Studying urban areas as urban ecosystems helps to better understand how ecosystem services, including the cycling of matter and flow of energy, connect the urban population and its surrounding environment. Urban ecology uses the methods of both natural science and the social sciences to study urban processes, trends, and patterns in the context of four variables: population, organization, environment, and technology.

These variables do not function independently of one another; they are interrelated and interact much like the parts of natural ecosystems. Moreover, like natural ecosystems, cities are open systems. The human population in an urban environment requires inputs from the surrounding countryside and produces outputs that flow into surrounding areas.

2. What are brownfields?

A brownfield is an urban area of abandoned, vacant factories, warehouses, and residential sites that may be contaminated from past uses.

3. Why are cities associated with urban heat islands and dust domes?

Streets, rooftops, and parking lots in areas of high population density absorb solar radiation during the day and radiate heat into the atmosphere at night. Heat released by human activities such as fuel combustion is also highly concentrated in cities. The air in urban areas is therefore warmer than the air in the surrounding suburban and rural areas and is known as an urban heat island. The local air circulation patterns of urban heat islands contribute to the buildup of pollutants, especially particulate matter, in the form of dust domes over cities. Pollutants concentrate in a dust dome because convection lifts

Chapter 9 pollutants into the air, where they remain because of somewhat stable air masses produced by the urban heat island.

4. What is compact development?

Compact development is the design of cities in which tall, multiple-unit residential buildings are close to shopping and jobs, and all are connected by public transportation.

Urban Land Use Planning 1. How does zoning help regulate urban land use?

Land use planning is the process of deciding the best uses for land in a given area. The main way that cities regulate land use is by zoning, in which the city is divided into use zones, areas restricted to specific land uses (i.e., commercial, residential, industrial).

Zoning has largely resulted in separation of industrial parks, shopping centers, apartment districts, and other land uses.

2. How are transportation and land use linked?

Transportation and land use are inextricably linked, because as cities grow, they expand along public transportation routes. Automobiles have increased the city’s spatial scale: The interstate highway system and beltway “loops” have encouraged development far from the city’s central business district.

3. What is suburban sprawl?

Suburban sprawl is a patchwork of vacant and developed tracts around the edges of cities; sprawl contains a low population density. Sprawl cuts into the surrounding rural land and causes environmental problems such as loss of wetlands, loss of biological habitat, air pollution, and water pollution.

Making Cities More Sustainable 1. What features does a sustainable city possess?

A sustainable city is a city with a livable environment, a strong economy, and a social and cultural sense of community. Sustainable cities: (1) enhance the well-being of current and future generations of urban dwellers; (2) have clear, cohesive urban policies that enable the government infrastructure to manage it effectively; (3) use energy and other resources efficiently and make use of renewable energy as much as possible; (4) reduce pollution and wastes by reusing and recycling materials; (5) have large areas of green space; and (6) are people-centered, not automobile centered.

2. Why is Curitiba, Brazil, a model of sustainability in the developing world?

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Chapter 9 Curbita, Brazil is a model of sustainability in the developing world because it developed an inexpensive, efficient mass transit system that uses clean, modern buses that run in high-speed bus lanes. Additionally, high-density development was largely restricted to areas along the bus lines. Curbita uses a special low-polluting fuel in its automobiles. It has also purchased and converted flood-prone properties along rivers in the city to a series of interconnected parks crisscrossed by bicycle paths. This has helped reduce flood damage and increased the per capita amount of green space.

Chapter 10 Energy Consumption Lecture Outline: I.

Categories of Energy a. Transportation b. Industry (including agriculture) c. Buildings II. While technological improvements can reduce the amount of energy consumed by any of the three categories, recent developments show that it is possible to design commercial and residential buildings that require no energy beyond that provided by the sun.

III. The Omega Center for Sustainable Living in New York a. Represents the promise of technologies b. Green design c. Completed in 2009 d. Building operated for its first year with no net energy use e. Natural filters and a designed wetland processes the waste water not only for the building but for the rest of Omega campus f. First ever to be certified by LEED Platinum and a Living Builder IV. LEED (Leadership in Energy and Environmental Design) a. Certification was first developed in 1998 b. US Green Building Council c. Has changed the way thousands of buildings are designed d. LEED certified buildings i. Use far less energy ii. Provides better living and working conditions iii. In order to qualify for different certifications 1. must have sustainable design features in categories a. energy b. materials c. indoor air quality iv. designers need to demonstrate a building perform as intended over time v. Living Building Challenge 1. all energy is generated on site from renewable resources 2. all waste water is treated on site using natural processes 3. no hazardous materials or chemicals are used in construction or operation 4. Not awarded until building has operated successfully for at least one year 5. only a few buildings are recognized under this new standard 6. several new projects are in design or in the construction phase 7. builders need to obtain to have green design features V. Energy Consumption and Policy a. Many energy sources have been described recently as clean, including: i. Coal ii. Solar iii. Nuclear power b. No energy source is clean c. Energy sources vary in their advantages and disadvantages d. Everything humans do require energy i. We use energy to move and build things

Chapter 10 ii. Heat, cool and illuminate our living and work spaces iii. Plant, water, harvest, process, ship and store food iv. Energy is required to capture energy 1. drill and pump oil 2. mine coal and uranium 3. build solar panels 4. install wind turbines e. A few hundred years ago almost all energy used by people was derived by agricultures i. Including wood, dung, and peat, wind or water f. Energy sources were local g. Activities were limited by the amount of useful energy that could be extracted from them h. Small amount of useful energy can be extracted from a bucket full of wood compared to the same amount of gasoline i. A few thousand years ago: i. The discovery of fire ii. Domestication of animals iii. Later the invention of windmills iv. Sailing ships significantly increased people’s ability to manipulate their environment. v. These were minor compared to how we can capture from 1. fossil fuels 2. nuclear 3. large-scale use of hydropower 4. solar 5. wind 6. biomass j. Advantages of energy sources include: i. How concentrated they are ii. Availability iii. Safety iv. Versatility k. Disadvantages include: i. Hazard potential ii. Environmental damage iii. Cost VI. Energy Consumption a. A conspicuous difference in per capita energy consumption exists between highly developed and developing countries i. Highly developed countries consume much more energy per person than developing countries ii. Although less than 20% of the world’s population lived in highly developed countries in 2010, they used 60% of the commercial energy consumed worldwide. iii. World energy consumption has increased every year since 1982. iv. A goal of many developing countries is to improve their standard of living.

1. one way to achieve this goal is through economic development a. A process usually accompanied by a rise in per capita energy consumption. v. China’s population is much larger than that of the United States, so its per capita energy use- the amount used per person-is considerably smaller

Chapter 10

VII.

VIII.

vi. The United States has one of the world’s highest per capita energy use per person per year.

Energy Efficiency and conservation a. Energy efficiency measures include designing and manufacturing more fuel-efficient automobiles, where energy conservation measures include carpooling and reducing trips i. Both efficiency and conservation accomplish the same goal---saving energy b. Efficiency and conservation can cost less than development of new sources of supplies of energy i. They improve the economy’s productivity ii. The adoption of energy-efficient technoloies generates new business opportunities 1. including research 2. development 3. manufacture 4. and marketing of those technologies iii. Many technologies and practices are already known but are slow to be adopted to both habit and relatively low energy prices iv. Some economic benefits and energy resources savings environmental benefits results from greater energy efficiency and conservation 1. using more energy-efficient appliances could cut CO2 emissions by millions of tons each year 2. slowing global climate change 3. Energy conservation and energy efficiency reduce air pollution 4. acid precipitation 5. and other environmental damage related to energy production and consumption Energy Efficiency a. Energy efficiency is a measure of the amount of available energy in a source that is transformed into useful work b. Energy efficiency ranges from 0 to 100% i. For example burning natural gas for household cooking has an efficiency of close to 100%--almost all the energy contained in the natural gas can be converted into heat in a stove or oven ii. In contrast, burning natural gas to generate electricity has a maximum efficiency of about 60%.

1. This means we would need almost twice as much natural gas to generate electricity to cook at home as we would if we burned the gas at the same home. iii. Lightening has become significantly more efficient over the 100 years since Thomas Edison invented the first incandescent (glowing wire) light bulb.

1. Current incandescent bulbs convert only 2-3% of the energy they receive into useful light, the other 97-98 % is wasted as heat.

2. In contrast, compact fluorescent light bulbs are about 10% efficient in converting electricity into light, while light emitting diodes (less common, but increasing in popularity) convert up to 20% of electricity into light. iv. Given the amount of lighting in use worldwide, the five-fold increase in efficiency gained by shifting from incandescent to compact fluorescent lighting could mean substantial reduction in energy use to gain the same energy service. v. Switching to different light bulbs can have some downsides 1. Compact fluorescents cost much more than do incandescent bulbs

Chapter 10 2. Light they put out is not as pleasant as that from an incandescent bulb

In Class Activities Instructor Notes for In-Class Activity 1 Title:

Examples of Fossil Fuels.

Time: Materials:

10 minutes prep; 15 – 25 minutes in class Samples of fossil fuels (and charcoal, firewood, candles, etc). This can include camping propane, vials of different sorts of crude, diesel and gasoline (be sure to used approved containers!), pieces of coal (more than one kind, ideally), different sorts of charcoal, pressed firewood and other firewood.

Alternatively, you may wish to bring images that can be accessed at industry websites.

None

Handouts: Procedures:

Have students inspect the different sorts of fossil and biomass fuels. Then have them, in groups of 3 -5, make notes about color, weight, fluidity. Then have them research (using the text and internet resources) the advantages and disadvantages of the different fuels for different purposes.

Some relevant attributes of fuels: • Energy density • Transportability • Volatility • Storability Some uses • Vehicle fuel (cars, trucks, busses, ships, trains) • Electricity generation • Industrial heating and manufacture Have students think about and discuss why coal became the first major industrial fuel.

Student Instructions: Specific Suggestions:

See above

Objectives:

Define fossil fuel, and distinguish between coal, oil and natural gas.

Be sure student understand what charcoal is, how it is created. In particular, be sure that they are aware that it is NOT a fossil fuel.

Instructor Notes for In-Class Activity 2 Title:

Diary of the energy you use

Time: Materials: Handouts:

5 – 10 minutes prep; 1 week out of class time Notebook None

Procedures:

Discuss with students the amount of energy used for an average household. Can

Chapter 10 we live without certain forms of energy produced from coal, oil and natural gas?

Have the students keep a diary of the energy they use from the time they get up to the time they go to bed. They may need a small pocket notebook to keep with them so they can keep track of the energy they use not only at home but in school, to and from school, at their jobs etc.

Student Instructions:

Take a small notebook that is easily kept with you and every time you use any form of energy by natural gas, coal, or oil, you will write it down with the time use and estimate how much was used. Note: You might check and see if your electricity is fueled by gas, coal or oil. Or you could put another line to monitor the amount of electricity used and do your calculations later. After you spend a week collecting data on your use of gas, oil

Specific Suggestions:

None

Objectives:

• •

Describe the dependency on oil, natural gas and coal is it a reality in your area.

Compare per capita energy consumption in highly developed and developing countries.

Instructor Notes for In-Class Activity 3 Title:

Wood: Renewable or Non-Renewable Resource?

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) Internet access a plus None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: Because new trees can be grown to replace cut trees, they should be thought of primarily as a renewable resource Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

Chapter 10 The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which, if either, provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student Instructions:

See above

Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

• •

Describe the difference between renewable and non-renewable resources Explain how wood can be used as a source of energy

Instructor Notes for In-Class Activity 4 Title:

Fueling a Hydrogen Vehicle Fleet

Time: Materials: Handouts:

10 minutes prep; 20 - 30 minutes in class Internet access None

Procedures:

In order for fuel cells to serve as a substantial substitute for internal combustion engines, the fuel cells need to run on a readily available fuel. It is possible to build gasoline fuel cells, but hydrogen is typically considered the best alternative. Unfortunately, in order for hydrogen to be readily available, an enormous amount of infrastructure must be developed. Our current gasoline station network has grown and evolved along with motor vehicles over the past century. It is not clear how easy it will be to develop hydrogen vehicles and a hydrogen supply infrastructure.

In this exercise, students will explore what if any hydrogen fueling opportunities exist in your area.

Student Instructions:

Working in groups of 3-4, answer the following questions: 1. How many gasoline stations are there within 5 miles of campus?

2. About how many vehicles would you estimate use these stations each day? This will provide a rough context for the number of hydrogen fueling stations that would be needed in order to switch over to fuel cell

Chapter 10 vehicles 3. How much do hydrogen fuel cell vehicles currently cost? How much do people expect them to cost in the next 20 years? What are the main advantages and limitations for hydrogen fuel cell vehicles?

4. Try to find out whether there are any hydrogen fueling stations within 50 miles of your campus. Check newspaper reports, government fleet centers. If you do find a nearby hydrogen station, estimate how far you would be able to drive on one tank with current technology. Is there another fueling station within that range (in other words, could you take a trip!)

5. Find out how hydrogen is delivered to hydrogen fueling station. Would delivery create any problems in your area?

Write up a summary of your findings. What do you think will be the biggest hurdles to a shift to a national hydrogen fuel cell fleet? Based on your research, do you think it’s likely that we will have a substantial number of hydrogen fuel cell vehicles in the next 20 years?

Specific Suggestions: Objectives:

If there is a hydrogen facility in your area, try to visit it, and see how an actual fuel cell vehicle works.

Describe the advantages and limitations of a fuel cell fleet.

Instructor Notes for In-Class Activity 5 Title:

Energy Conservation on Campus

Time: Materials: Handouts:

10 minutes prep; 30 – 50 minutes in class Access to internet, campus map None

Procedures:

Have students generate a list of the biggest things that a campus could do to conserve energy, and compare these to the other groups’ observations.

Next, tour the campus and evaluate the extent to which conservation measures could be improved. Have students go to different parts of campus and mark these on the campus map. Have them keep in mind that campus energy use can involve not only heating, cooling and lighting, but also such things as transportation (including parking lots for students driving alone), watering, and deliveries.

Finally, have them regroup and discuss their findings.

1. How many improvements could be made at little or no financial cost?

2. How many improvements could be made with little or no impact to student or faculty/staff lifestyles? (And of these, how many are aesthetic impacts, and how many require substantial behavioral changes?)

3. Do any items from 1 or 2 overlap, or must there be sacrifices for conservation?

Student Instructions:

Working in groups of 3-4, generate a list of the biggest things that a campus could do to conserve energy.

Compare these to the other groups’ observations.

Next, go to the part of campus you are assigned by your instructor, and evaluate the extent to which conservation measures could be improved.

▪ Keep in mind that campus energy use can involve not only heating,

Chapter 10 cooling and lighting, but also such things as transportation (including parking lots for students driving alone), watering, and deliveries.

Return to class when assigned, and discuss your findings with the rest of the class Specific Suggestions:

If possible, bring in someone from the energy / facilities group on campus to discuss conservation measures.

Objectives:

Describe conservation opportunities and their financial and cultural implications.

Answers to End of Chapter Critical Thinking Questions 1. Why is it useful to know both per capita energy use and total energy use for a country?

Ans: Per capital energy use is the amount of energy used per person. It is important when examining a countries total energy use to also determine how much energy is being used per person. The goal of many developing countries is to improve the standard of living of their citizens. Normally this is accomplished through economic development which is usually accompanied by a rise in per capita energy consumption.

For example in 2008 China consumed 90 billion GJ of the world’s total energy compared to 105 billion GJ for the US but since China’s population is so much larger than the US its per capital energy use is considerably smaller.

2. Which has a higher energy density: wood or a car battery?

Ans: Energy density is the amount of energy stored per unit volume of a region of space or a given system. Often only the useful energy is quantified. Only a small amount of useful energy can be extracted from wood compared to the amount that can be extracted from a car battery.

3. What are the relative advantages and disadvantages of fluorescent and incandescent lighting?

Ans: Lighting has become significantly more efficient over the past 100 years. Incandescent bulbs convert only about 2-3% of the energy they receive into useful light; the rest is wasted as heat. Incandescent bulbs are normally less expensive than fluorescent lighting but they normally do not last as long. Fluorescent bulbs convert about 10% of the energy they receive into useful light but cost considerably more than incandescent. Fluorescent bulbs normally last longer than incandescent bulbs but some people do complain that the light produce by fluorescent bulbs is not as pleasing as the light from incandescent.

4. List energy conservation measures you could adopt for each of the following aspects of your life: washing laundry, lighting, bathing, cooking, buying a car, and driving a car.

Ans: Washing laundry: Purchasing and using a new washing machine. Appliances built since 2001 consume 75% less energy than models built in the mid-1970s. Use only the cold cycle and make sure that the washing machine is filled to recommended capacity instead of washing loads at less than capacity.

Decide to purchase a front-loading washing machine over a traditional top-loader to save on water and detergent.

Lighting: Replace incandescent bulbs with fluorescent or light emitting diodes. Make sure you turn off the lights when you leave the room.

Bathing: Instead of bathing you can shower conserving water and energy. Replace your traditional hot water tank with an instant on water heater to save even more energy.

Cooking: Replace your old stove with a newer more efficient unit.

Chapter 10 Car: You can purchase a vehicle that is fuel efficient and/or you can buy a hybrid vehicle to improve your gas mileage.

Driving a car: Plan your route and trip out before so you make the least amount of stops. Accelerate slowly at stop signs and red lights so you conserve gas and drive within the speed limit and maintain proper tire pressure and engine maintenance to maximize fuel efficiency.

5. How would the list in item 4 differ if you were to take a systems perspective rather than a short-term perspective? Would it be easy to implement these changes? Why or why not?

Ans: Answers will vary but will focus on integrating the individual components into a more efficient system. A system approach will shift the focus from the individual parts to the whole allowing a better understanding of the connections between all of the different components. System perspectives can be applied successfully to improve energy efficiencies but careful planning must be done in advance to ensure that all of the individual components are design and located to maximize efficiency. If careful planning and research is conducted to maximize interaction of the various components before building them greater overall efficiency can be obtained.

6. What energy sources are used to generate electricity where you live, work, or go to school? This information is usually available on utility bills or at the utility website.

Ans: Answers will vary but will normally include coal, oil, natural gas, nuclear, geothermal, wind, and solar.

7. When are electricity and hydrogen “climate-neutral”? Can electricity or hydrogen produced using the energy of coal be climate-neutral? Why or why not?

Ans: Climate-neutral refers to achieving a net zero emission by offsetting the amount of emissions release with an equal amount sequestered. Climate neutral reflects the fact that it is not just carbon dioxide that is driving climate change but also includes methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulphur hexafluoride. Energy produced using renewable sources are normally considered climateneutral. Energy produced using non-renewable sources can be considered climate-neutral if offset with renewable energy that creates a similar amount of useful energy. An alternative approach that is critized by some is the practice of carbon offsetting in which the emissions produced from non-renewable energy sources is offset by planting trees or by funding projects that will lead to the prevention of greenhouse gases or through carbon trading.

8. What forms of energy storage do you use? What are the benefits of this energy storage?

Ans: Answers will vary but will normally include batteries, potential energy, thermal energy, chemical energy, electrochemical energy, kinetic energy, and superconducting magnets.

The benefit of storing energy is that it will be available when it is needed. By storing unused energy until it is needed there will be less chance of intermittent or reduction in available energy. The negative of all energy storage technologies is that they are less than 100% efficient. Whenever energy is converted from one energy form to another some of the useful energy is lost in the conversion.

9. What is the national energy policy of the United States? Does it include subsidies? Does it promote efficiency and/or conservation?

Ans: The energy policy of the United States is determined by federal, state, and local public entities. The energy policy addresses the issues of energy production, distribution, and consumption. The United States has not adopted a comprehensive long-term energy policy. The national policy does include acts that provide provisions for energy conservation including the energy star program and grants and tax

Chapter 10 incentives for both renewable energy and non-renewable energy. The national energy policy does include subsidies for biofuels, consumer subsidies (hybrid vehicles, insulation, solar, etc.) and subsidies for nuclear, fossil fuel production, clean coal technologies, conservation and efficiency improvements.

10. The German Federal Ministry for Economic Development and Cooperation use gasoline policies to classify countries into four categories: 1. Very high subsidies; 2. Subsidies; 3. Taxation; 4.Very high taxation. The November 2008 retail cost to consumers of regular gasoline in representative countries is found in the figure below. How do you think these prices impact conservation and efficiency for passenger vehicles in those countries?

Ans: There is usually an inverse relationship between the amount of subsidy a country does to keep gasoline prices artificially low and the effort of conservation and fuel efficiencies in vehicles driven in those countries, (i.e. more subsidy results in more vehicles being driven with lower m.p.g.). Alternatively the higher the taxation on gasoline normally results in more fuel efficient vehicles being driven, better mass transit and more effort to conserve energy.

Answers to Review Questions Energy Consumption and Policy, pg. 198 1. How does the concentration of energy in a source affect how people can use energy?

The concentration of energy in a source determines the amount of useful energy that can be extracted from a given volume or mass of fuel. The concentration of energy has increased people’s ability to manipulate their environment. Concentrated fuels typically have greater potential for geographic distribution, portability, and versatility. In addition, electricity and, increasingly, hydrogen have allowed for the concentration of large amounts of useful energy to be obtained from a wide range of sources. Modern transportation, industry, agriculture, and buildings rely on highly concentrated fuels like coal and gasoline.

2. How do the United States, China, and Kenya compare in total energy consumption? In per capita energy consumption?

In general, energy consumption in highly developed countries (i.e., the United States) is much greater than it is in developing countries (i.e., Kenya); and, in moderately developed countries (i.e., China), energy consumption is rapidly increasing due to greater industrialization and economic development. In fact, China has more than doubled its energy consumption over the past decade. In terms of energy supply and use, both the United States (at 22%) and China (at 17%) are responsible for large portions of total world energy consumption, while Kenya is only responsible for 0.04%. However, when analyzing energy consumption in terms of the amount used per person, the United States far outweighs China’s consumption. The per capita energy use in the United States is about 56 GJ per person per year; nearly 6 times as much as is used in China and about 60 times as much as is used by the average Kenyan.

Energy Efficiency and Conservation, pg. 205 1. How can the same energy services be provided with less energy for lighting? For transportation?

Energy services are the benefits we get from using energy. They include transportation, industry, agriculture, commercial and household energy use. More efficient practices and technologies can

Chapter 10 allow us to get more energy services from a given amount of an energy source. For example, the simple shift from the use of incandescent to compact fluorescent lighting could result in up to a five-fold increase in lighting energy efficiency worldwide. With regards to transportation, the same energy services can be provided with less energy by using lighter materials for car bodies, frames, and engines. Additionally, designing cars to minimize wind resistance, operate electrically, and recapture energy wasted as the vehicle slows could also significantly contribute to greater energy efficiency in transportation.

2. When does conservation reduce quality of life? Improve quality of life?

Improving energy efficiency usually means changing behaviors, practices, and expectations of services derived from energy. In general, energy conservation saves money, reduces pollution, and reduces our reliance on foreign energy sources. These are, by and large, all positive aspects of energy conservation. However, some forms of energy conservation, such as maintaining a lower indoor temperature in winter, are seen by some as a reduction in quality of life. Because quality of life is a subjective idea, there will always be opposing opinions regarding this matter.

For example, a conservation measure such as switching from driving to walking can have both benefits (i.e., health and cost savings) and downsides (i.e., longer commute time).

Electricity, Hydrogen, and Energy Storage, pg. 209 1. What are some ways that electricity can be used?

Electricity has been in use for over a century and will probably play an increasing role in the future. It is a versatile form of energy, and can easily be converted into light, heat, or motion. It can be released in very small, precise amounts (i.e., in delicate electronic equipment) or with enough power to move a freight train at high speeds.

2. What are some uses for hydrogen fuel cells?

Hydrogen fuel cells can provide energy for a range of uses. In addition to powering automobiles and other forms of transportation, banks of fuel cells can provide electricity for buildings or factories. Some companies are also looking at smaller applications of the hydrogen fuel cell, such as replacing batteries in cell phones and laptop computers.

3. What are some pros and cons of storing energy as hydrogen? In batteries? In flywheels?

Hydrogen can store energy from a variety of sources and can be used to store chemical energy; but, like all energy storage technologies, it is less than 100% efficient. Flywheels can store kinetic energy which can later be recaptured by operating a motor as a generator that converts the kinetic energy into electrical energy as it slows the spin. However, friction eventually dissipates much of this kinetic energy into wasted heat. Batteries are the most common forms of electrochemical energy storage because they are typically stable and can hold a charge for an extended period. Yet, additional disadvantages to battery storage include the expense to build and maintain them, and the environmental problems created by their disposal and/or recycling.

Energy Policy, pg. 210 1. How do policy decisions affect the development of energy technologies?

Chapter 10 Energy policy decisions can encourage or discourage particular energy resources, both through subsidizing the development of some sources but not others and through funding research to develop future energy sources. Additionally, policy decisions can influence which technologies get used. For example, minimum vehicle fuel-efficiency standards promote conservation, while the planning that focuses on building large, unimpeded roadways promotes car ownership.

Chapter 11 Fossil Fuels Lecture Outline: I. Fossil Fuels A. Energy is obtained from a variety of sources, including fossil fuels (coal, oil, and natural gas), nuclear reactors, biomass, solar and other alternative energy sources (water, wind, etc.) i. Fossil fuels supply most of the energy required in North America ii. They are nonrenewable resources; formation does not keep pace with current use B. How fossil fuels are formed i. Coal was formed from the remains of ancient plants that lived millions of years ago ii. Oil was formed from the remains of ancient microscopic aquatic organisms iii. Natural gas is composed primarily of methane and was created in much the same way as oil, except at higher temperatures II. Coal A. In the 18th century, coal replaced wood as the dominant fuel in the Western world i. Coal powered the steam engine and supplied the energy for the Industrial Revolution ii. Today it is used to produce electricity and steel iii. Coal consumption has surged in recent years in China and India B. Lignite, subbituminous coal, bituminous coal, and anthracite are the four most common grades of coal i. Lignite is a soft, moist coal that produces little heat and is often used to power electric power plants ii. Subbituminous coal has a relatively low heat value and sulfur content, and is also used in coal-fired electrical power plants iii. Bituminous (soft) coal produces substantially more heat that the lignite or subbituminous, but also contains a higher sulfur content; it is used extensively in electric power plants iv. Anthracite (hard) coal is the highest grade of coal and produces the fewest pollutants per unit of heat released (due to low sulfur content); it has the highest heat-producing capacity of any grade of coal C. Coal reserves i. Coal is the most abundant fossil fuel in the world, and is found primarily in the Northern Hemisphere ii. World coal reserves could last more than 200 years at the present rate of consumption D. Coal mining i. Surface mining extracts the mineral and energy resources near Earth’s surface by first removing soil, subsoil, and overlying rock strata 1. It is used to obtain 60% of the coal mined in the U.S

Chapter 11 2. It is often cheaper, safer, and generally allows more complete removal of coal from the ground 3. It does, however, have the potential to cause more serious environmental problems ii. Subsurface mining extracts the mineral and energy resources from deep underground deposits E. Safety problems associated with coal i. During the 20th century, more than 90,000 American coal miners died in mining accidents ii. Miners have increased risk of cancer and black lung disease F. Environmental impacts of the mining process i. Prior to 1977 (SMCRA – the Surface Mining Control and Reclamation Act), abandoned surface coal mines were usually left as large open pits or trenches and streams were polluted with sediment and acid mine drainage ii. The SMCRA requires coal companies to restore areas that have been surface mined, requires permits and inspections of active coal mine operations, and prohibits coal mining in sensitive areas iii. Mountaintop removal is one of the most land-destructive types of surface mining; it uses a dragline to remove the mountain top to reach the coal below G. Environmental impacts of burning coal i. The Earth’s CO2 equilibrium has been disrupted by the enormous amounts of CO2 produced through fossil fuel consumption this past century ii. This, in turn, has lead to a rise in global temperature and various environmental issues associated with higher temperatures 1. Melting of polar ice caps 2. Rising sea levels 3. Future flooding of coastal areas, increasing coastal erosion and associated violent storms iii. Coal burning generally contributes more air pollutants (including CO2) than does burning either oil or natural gas (i.e., mercury, sulfur oxides, nitrogen oxides, and acid deposition) H. Making coal a cleaner fuel i. It is possible to reduce sulfur emissions associated with the combustion of coal by installing scrubbers to clean the power plant’s exhaust 1. Modern scrubbers remove 98% of the sulfur and 99% of the particulate matter in smokestacks 2. Desulfurization systems are very expensive ii. Selling the sulfurs or metals removed from polluted emissions as a marketable product is called resource recovery iii. The Clean Air Act Amendments of 1990 required the nation’s 111 dirtiest coalburning power plants to cut sulfur dioxide emissions 1. This cut emissions by 3.8 million metric tons nationwide 2. The second phase of this amendment called for 200 additional power plants to make SO2 cuts by 2000 a. This reduced the total annual emission by 10 million metric tons nationwide

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Chapter 11 b. A nationwide cap on SO2 emissions was imposed after 2000 iv. Clean coal technologies are new methods being developed for burning coal that will not contaminate the atmosphere with sulfur oxides and will significantly reduce nitrogen oxide contamination 1. Fluidized-bed combustion and coal gasification and liquefaction are two new clean coal technologies 2. These new technologies have little impact on reducing CO2 emissions III. Oil and Natural Gas A. Beginning in the 1940s, oil and natural gas became increasingly important as energy sources due to easier transport and cleaner burning i. In 2005, oil and natural gas supplied 63% of the energy used in the U.S. ii. In 2004, oil and natural gas supplied 60.6% of the world’s energy B. Petroleum (crude oil) is separated into gases, gasoline, heating oil, diesel oil, and asphalt during the refining process C. Oil is used to produce petrochemicals used in fertilizers, plastics, paints, pesticides, medicines, and synthetic fibers D. Natural gas is separated into propane, butane, and ethane; it costs four times more to transport through pipelines than crude oil i. Liquefied petroleum gas (propane and butane) is used as fuel for heating and cooking ii. Natural gas is used to produce both electricity and steam in a process called cogeneration iii. Natural gas as a fuel for trucks, buses, and automobiles offers significant environmental advantages over gasoline or diesel E. Exploration for oil and natural gas i. Oil and natural gas deposits are usually discovered indirectly by the detection of structural traps; geological analysis to find structural traps is extremely expensive ii. Many important oil and natural gas deposits are found in association with salt domes F. Reserves of oil and natural gas i. Distribution is uneven; a large share of total oil deposits are clustered relatively close together (Persian Gulf region, Venezuela, Mexico, Alaska, etc.) ii. Almost half of the world’s proved recoverable reserves of natural gas are located in Russia and Iran iii. Many countries engage in offshore drilling for oil despite problems such as storms at sea and the potential for major oil spills G. How long will oil and natural gas supplies last? i. Some experts think that global oil production has already reached Peak Oil (aka Hubberts Peak), others believe it will be reached around 2035 ii. About 80% of current production comes from oil fields discovered before 1973, and most of these have started to decline in production H. Global oil demand and supply i. The U.S. currently imports more than half of its oil; this dependence has potential international security implications as well as economic impacts

Chapter 11 ii. The imbalance between oil consumers and oil producers will probably worsen in the future because the Persian Gulf region has much higher proven reserves than other countries I. Environmental impacts of oil and natural gas i. Problems that result from burning fuels (combustion) 1. Every gallon of gas burned in a car releases an estimated 9kg of CO2 into the atmosphere; global warming results from increased CO2 in the atmosphere 2. Increased acid deposition, photochemical smog, and increased particulate matter result from combustion ii. Problems such as serious spills along transportation routes are involved in obtaining fuels IV. Synfuels and Other Potential Fossil Fuel Resources A. Synfuels are fuels that are similar or identical to the chemical composition of oil or natural gas (i.e., tar sands, oil shales, gas hydrates, liquefied coal, and coal gas) B. Synfuels are more expensive to produce than fossil fuels C. Environmental impacts of synfuels i. Synfuels have many of the same undesirable effects as fossil fuels 1. Release of CO2 and other pollutants into the atmosphere 2. They require large amounts of water during production; limited usefulness in arid lands ii. Large areas of land would have to be surface mined to recover the fuel in tar sands and oil shales V. The U.S. Energy Strategy A. A comprehensive national energy policy should consider the following elements i. Increase energy efficiency and conservation ii. Secure future fossil fuel energy supplies iii. Develop Alternative Energy Sources iv. Meet the first three objectives without further damage to the environment B. How politics influences the national energy policy i. The Energy Policy Act of 2005 focuses largely on supporting energy research for fossil fuels ii. Subsidies continue

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Chapter 11

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Examples of Fossil Fuels.

Time: Materials:

10 minutes prep; 15 – 25 minutes in class Samples of fossil fuels (and charcoal, firewood, candles, etc). This can include camping propane, vials of different sorts of crude, diesel and gasoline (be sure to used approved containers!), pieces of coal (more than one kind, ideally), different sorts of charcoal, pressed firewood and other firewood.

Alternatively, you may wish to bring images that can be accessed at industry websites.

None

Handouts: Procedures:

Have students inspect the different sorts of fossil and biomass fuels. Then have them, in groups of 3 -5, make notes about color, weight, fluidity.

Then have them research (using the text and internet resources) the advantages and disadvantages of the different fuels for different purposes.

Some relevant attributes of fuels: • Energy density • Transportability • Volatility • Storability Some uses • Vehicle fuel (cars, trucks, busses, ships, trains) • Electricity generation • Industrial heating and manufacture Have students think about and discuss why coal became the first major industrial fuel.

Student See above Instructions: Specific Be sure student understand what charcoal is, how it is created. In Suggestions: particular, be sure that they are aware that it is NOT a fossil fuel.

Objectives:

Define fossil fuel, and distinguish between coal, oil and natural gas.

Chapter 11

Instructor Notes for In-Class Activity 2 Title:

Geography, Fossil Fuels and the Future

Time: Materials: Handouts:

5 minutes prep; 15 – 20 minutes in class Figures depicting coal, oil and natural gas resources by country None

Procedures:

Have students, working in groups of 3 – 4, look at which countries or regions have access to ANY or SOME fossil fuels. Have them pay particular attention to which less developed countries have little or no domestic energy resources. Then have them consider these questions, and report back to the class for a larger discussion: 1. Are domestic fossil fuel resources necessary for development?

2. What are the development options for a less developed country that has few if any domestic fossil fuel resources?

3. Do all highly developed countries have domestic fossil fuel resources? If not, where and how did they access the fuels used for development?

Student See above Instructions: Specific None Suggestions: Objectives:

Compare energy use in highly developed and developing countries.

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Instructor Notes for In-Class Activity 3 Title:

Phase I and Phase II Vapor Recovery

Time: Materials:

5 – 10 minutes prep; 15 – 30 minutes in class Old nozzle from a gasoline station (or images, available at vendor websites); images of gasoline trucks unloading at a local gas station.

Better yet, get permission to tour a gas station while a truck is off-loading gasoline.

None

Handouts: Procedures:

In many areas, Phase I (capturing vapors from emptied underground tanks) and Phase II (capturing vapors in emptied automobile gas tanks) vapor recovery systems are required. Gasoline vapors can represent a significant contribution to the creation of ground level ozone.

Most students are familiar with Phase II equipment, whether or not they are aware. As gasoline goes into an empty tank, vapors are forced out of the tank. These vapors can be captured by a sheath around the nozzle, and returned through a second hose (often integrated into the main hose), and from there back into the underground tank.

Then, when the gasoline truck comes, as it empties, the vapors from the underground tank are returned to the truck. When the truck goes back to be filled, the vapors can be condensed into useable gasoline, or burned.

Assignments from students: • Inspect the nozzles and/or images.

• Take notes about the system design.

• Compare current designs with earlier designs • Estimate the amount of gasoline that is used in your area in a day. For each gallon of gas pumped, at least one gallon of vapors will be released to the atmosphere if it is not captured.

Student See above Instructions: Specific None Suggestions: Objectives:

Discuss the environmental problems of using oil.

Chapter 11

Instructor Notes for In-Class Activity 4 Title:

How much is left?

Time: Materials: Handouts:

5 – 10 minutes prep; 30 minutes None None

Procedures:

Divide the class into three groups.

Let them pick out of a hat which group they will be researching. You will have an OIL team, Natural Gas Team and a Coal Team. Their assignment is to prepare an obituary for their fuel and present it to the class. They might want to write it up in Newspaper format.

Student You have been assigned a product either OIL, Natural Gas or Coal. The Instructions: earth has just run out of this material and you are to write an obituary for this product. Be creative and informative. Some of the things you might mention in your research for this obituary is the time spent on earth, the value, who was helped or hurt by the existence of your product etc.

Specific Suggestions:

None

Objectives:

• •

Define Fossil Fuel, and distinguish among coal, oil and natural gas.

Discuss the advantages and disadvantages of coal, oil and natural gas.

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Instructor Notes for In-Class Activity 5 Title:

Diary of the energy you use

Time: Materials: Handouts:

5 – 10 minutes prep; 1 week out of class time Notebook None

Procedures:

Discuss with students the amount of energy used for an average household. Can we live without certain forms of energy produced from coal, oil and natural gas? Have the students keep a diary of the energy they use from the time they get up to the time they go to bed. They may need a small pocket notebook to keep with them so they can keep track of the energy they use not only at home but in school, to and from school, at their jobs etc.

Student Take a small notebook that is easily kept with you and every time you use Instructions: any form of energy by natural gas, coal, or oil, you will write it down with the time use and estimate how much was used. Note: You might check and see if your electricity is fueled by gas, coal or oil. Or you could put another line to monitor the amount of electricity used and do your calculations later. After you spend a week collecting data on your use of gas, oil Specific Suggestions:

None

Objectives:

• •

Describe the dependency on oil, natural gas and coal is it a reality in your area.

Compare per capita energy consumption in highly developed and developing countries.

Instructor Notes for In-Class Activity 6 Title:

Only one type of fuel to use….what would it be?

Time: Materials: Handouts:

5 – 10 minutes prep; 30 minutes None None

Procedures:

Divide the class into three groups.

Let them pick out of a hat which group they will be researching. You will have an OIL team, Natural Gas Team and a Coal Team. Their assignment is to prepare a persuasive power point presentation to use their fuel source. They should address issues like history, good, bad and ugly.

Chapter 11 Student You have been assigned a product either OIL, Natural Gas or Coal. The Instructions: earth is deciding what to use for their main source of fuel. It is your responsibility to convince all the inhabitants of earth they can only use one source of energy and it must be either OIL, Natural Gas or Coal.

Your power point will cover the history of the fuel, and also the good, bad and ugly points of this fuel. Be creative and informative. Some of the things you might mention in your research how much is available, who uses it, why would it be the best fuel to use if the only one. Each power point presentation should be at least 15 slides, with references.

Specific Suggestions:

None

Objectives:

• •

Define Fossil Fuel, and distinguish among coal, oil and natural gas.

Discuss the advantages and disadvantages of coal, oil and natural gas.

Instructor Notes for In-Class Activity 7 Title:

In the News

Time: Materials: Handouts:

5 – 10 minutes prep; 30 minutes None None

Procedures:

Divide the class into three groups.

Let them pick out of a hat which group they will be researching. You will have an OIL team, Natural Gas Team and a Coal Team. Their assignment is to watch the news, whether it is news paper, internet, TV etc. Each team will get a point for the time their product is mentioned.

For example, if the nightly news mentions they are drilling for natural gas, the natural gas team will go to that news cast web site and print out the clip of the news item. At the end of the week, see which team has the most representation from the news sources.

Student You have been assigned a product either OIL, Natural Gas or Coal. You Instructions: are to go to all the news sources available to you: TV newscast, News paper, weekly magazines, Internet etc. Whenever there is a news clip on your type of fuel, you are to note it, possibly get a copy, and bring it in.

On the last day of the week, all clips will be brought in and the team with the most news clips wins.

Specific Suggestions:

None

Objectives:

• •

Discuss the information on your fuel source which is brought to the public.

Discuss the quality of information delivered to the public about each 183

Chapter 11 type of fuel source.

Activities 5,6,& 7 could be combined. Just a thought

Chapter 11

Answers to Critical Thinking and Review End of Chapter Questions: 1. The Industrial Revolution may have been concentrated in the Northern Hemisphere because coal is located there. What is the relationship between coal and the Industrial Revolution?

Ans: Although coal was used as a fuel for centuries, not until the 18th century did it begin to replace wood as the dominant fuel in the Western world. Since then, coal has had a significant impact on human history. It was coal that powered the steam engine and supplied the energy for the Industrial Revolution, which began in the mid-18th century. Today utility companies use coal to produce electricity, and heavy industries use coal for steel production. Coal consumption has surged in recent years, particularly in the rapidly growing economies of China and India, both of which have large coal reserves.

2. Few countries in Africa have significant amounts of coal, oil and natural gas resources. What does this suggest about opportunities for financial development in those countries?

Ans: With the exception of a few countries, Africa has few fossil fuel resources. Their only options for expanding energy use will be to purchase fossil fuels from other countries or develop alterative resources. Either of these approaches requires substantial financial capital—another resource generally lacking in developing countries. This will result in limited financial development opportunities for many counties.

3. Distinguish among fluidized-bed combustion, coal liquefaction, and coal gasification.

Ans: Fluidized-bed combustion is a clean-coal technology in which crushed coal is mixed with limestone to neutralize the acidic sulfur compounds produced during combustion. A nonalcohol liquid fuel similar to oil can be produced from coal, called coal liquefaction. The liquid fuel, which is cleaned before burning, is less polluting than solid coal. Coal gasification is production of the combustible gas methane from coal by reacting it with air and steam.

4. Which contributes the most to climate change per unit of useful energy: coal, oil, or natural gas?

Ans: Burning coal generally contributes more air pollutants (including CO2) than does burning either oil or natural gas. Coal also often contains mercury that is released into the atmosphere upon combustion.

5. Which of the following do you think could most effectively reduce the use of oil in the United States: reducing subsidies on fossil fuels, changing the design of cities, or requiring vehicles to be more efficient? Explain.

Ans: Answers will vary.

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6. What impact does drilling for oil in the United States have on short-term U.S. energy supplies? Long-term supplies?

Ans: In global markets domestic oil is indistinguishable from foreign oil. So while domestic oil may increase short-term supplies, it cannot have much impact on the percentage of petroleum that the United States buys from abroad. Conservationists point out that using domestic oil is a short-term fix and will, in the long run, lead to greater dependence on foreign oil.

7. How does extraction of natural gas from shale differ from extraction from sandstone?

Ans: Shale gas is much more difficult to extract than is gas found above oil in sandstone deposits. Natural gas must be freed from shale which means after the well is drilled water is pumped down and used to break the shale apart. This process is called hydraulic fracturing.

Hydraulic fracturing produces wastewater with high concentrations of salts and hydrocarbons.

The wastewater can also contain toxic metals and radioactive uranium.

8. On the basis of what you have learned about coal, oil and natural gas, which fossil fuel do you think the United States should exploit in the short term (during the next 20 years)? Explain your rationale.

Ans: Answers will vary.

9. Explain why the United States Department of Energy describes coal as a “true measure of the energy strength of the United States.” Is this also true of China? India? Why or why not?

Ans: Answers will vary.

10. Which of the negative environmental impacts associated with fossil fuels is most serious?

Why? Ans: Answers will vary.

11. Which major consumer of oil is most vulnerable to disruption in the event of another energy crisis: electric power generation, motor vehicles, heating and air conditioning, or industry? Why? Ans: Motor vehicles are most at risk for another energy crisis because they rely so heavily on gasoline. Electric power companies use coal to produce electricity, and heavy industries use coal

Chapter 11 for steel production. The United States has 25% of the world's coal supply in its massive deposits. Natural gas efficiently fuels residential and commercial air-cooling systems and well as heating systems.

12. What are the implications of “Peak Oil” on future global energy supplies?

Ans: The most optimistic predictions are for Peak Oil at around 2035. After which point global oil supplies will decrease and energy needs will have to be met by other sources.

Natural gas is more plentiful than oil. Experts estimate that readily recoverable reserves of natural gas, if converted into a liquid fuel, would be equivalent to between 500 billion and 770 billion barrels of crude oil, enough to keep production rising for at least 10 years after conventional supplies of petroleum have begun to decline. However, if the global use of natural gas continues to increase as it has in recent years, then its life supply will be much shorter than current projections predict. Analysts say the world must move quickly to develop alternative energy sources because the global demand for energy will only continue to increase.

13. Do you think we should permit more oil drilling off the coast of the United States? Why or why not?

Ans: Answers will vary.

14. Some environmental analysts think that the latest war in Iraq was related in part to gaining control over the supply of Iraqi oil. Do you think this is plausible? Explain why or why not.

Ans: Answers will vary.

15. What are the five kinds of synfuels? Why are they not being used more extensively?

Ans: Synfuels include tar sands, oil shales, gas hydrates, liquefied coal, and coal gas. Although synfuels are promising energy sources, they have many of the same undesirable effects as fossil fuels. Their combustion releases enormous quantities of CO2 and other pollutants into the atmosphere, thereby contributing to global warming and air pollution. Some synfuels, such as coal gas, require large amounts of water during production and are of limited usefulness in arid areas, where water shortages are already commonplace. Also, enormously large areas of land would have to be surface mined to recover the fuel in tar sands and oil shales.

16. Fossil fuels are “non-renewable” resources. Why does this pose a problem from a systems perspective? (Hint: Irreversible change disrupts system stability.)

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Chapter 11 Ans: Consuming fossil fuels at the current rate is not sustainable. We will use up our supply of these resources and be unable to replace them. Taking a systems perspective—one that accounts for long term cause and effect relationships and sustainability—might lead to a more efficacious energy policy.

17. What is the relationship between fossil fuels and greenhouse gases?

Ans: The combustion of fossil fuels releases large amounts of the greenhouse gas carbon dioxide. The equilibrium among CO2 in the atmosphere, CO2 dissolved in the ocean, and CO2 in organic matter changes over long periods - thousands or millions of years. Over the past century, however, we have released so much CO2 into the atmosphere through consumption of fossil fuels that Earth’s CO2 equilibrium has been disrupted.

18. The figure below shows projected annual energy use for the United States, India, and China. How much is each country’s energy use expected to increase between 2015 and 2035? What impact will this have on total global dioxide emissions if all of the increase comes from fossil fuels?

Ans: The United States annual energy use is projected to increase from 100 GJ per year in 2015 to 110 GJ in 2035, India annual energy use is projected to increase from 22 GJ per year in 2015 to 40 GJ per year in 2035, and China’s annual energy use is projected to increase from 100 GJ in 2015 to 175 GJ in 2035. Since the majority of the increase in annual energy use will come from the burning of fossil fuels this will result in a dramatic increase in global dioxide emissions unless the countries embrace carbon capturing and carbon storage technology.

Answers to Review Questions Fossil Fuels 1. What are fossil fuels?

Fossil fuels are combustible deposits in the Earth’s crust (i.e., coal, oil, and natural gas), composed of the remnants of prehistoric organisms that existed millions of years ago.

Chapter 11 Even though natural processes are still forming fossil fuels, they are forming too slowly to replace the fossil-fuel reserves we are using, and are therefore considered nonrenewable resources.

2. How are coal, oil, and natural gas formed?

Coal is a black, combustible solid formed from the remains of ancient plants that lived millions of years ago. Coal was formed when partially decomposed plant material was exposed to heat and pressure for aeons, forcing out water and concentrating energy in chemical bonds.

Oil is a thick, yellow to black, flammable liquid hydrocarbon mixture. It was formed when large numbers of microscopic aquatic organisms died and settled in the sediments.

As they accumulated, their decomposition depleted the oxygen present in the sediments.

The resultant oxygen-deficient environment prevented further decomposition. The heat and pressure caused by burial of more sediments aided in the conversion of these remains to the mixture of hydrocarbons known as oils.

Natural gas is a mixture of gaseous hydrocarbons that often occurs with oil deposits. It is composed primarily of the simplest hydrocarbon, methane, formed in essentially the same way as oil, only at higher temperatures (greater than 100°C).

3. What is the relationship between burning fossil fuels and atmospheric carbon dioxide?

The combustion of fossil fuels releases carbon into the atmosphere. In effect, the carbon dioxide concentration of the atmosphere is rapidly increasing from levels associated with a relatively cool climate to levels associated with a substantially warmer climate. This is in part due to the fact that the energy and carbon accumulated over millions of years in fossil fuels is now being released in just a few hundred years. This rapid release of stored carbon has disrupted the Earth’s equilibrium of carbon dioxide in the atmosphere.

Coal 1. Which type of coal mining - surface or subsurface mining – is more land-intensive?

Surface mining disrupts the land much more extensively than subsurface mining, and has the potential to cause several serious environmental problems.

2. What are acid mine drainage and acid deposition?

Both acid mine drainage and acid deposition are two significant types of pollution associated with coal mining and combustion. Acid mine drainage is pollution caused when sulfuric acid and dangerous dissolved materials such as lead, arsenic, and cadmium wash from coal and metal mines into nearby lakes and streams. Acid deposition is a type of air pollution in which acid falls from the atmosphere to the surface as precipitation (acid precipitation) or as dry acid particles.

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Chapter 11 3. What are the environmental benefits of resource recovery? Of fluidized-bed combustion?

Resource recovery is the process of removing any material from polluted emissions or solid waste and selling it as a marketable product. In the case of sludge from lime scrubbers, instead of disposing this sludge in landfills, the sludge is treated as a marketable product and sold to wallboard manufacturers and farmers (for soil conditioning). Similarly, fly ash from chimney flues can be used to make lightweight concrete. This acts as a win-win for the environment, by reducing waste and providing alternative sources of materials from recycled waste.

Fluidized-bed combustion is a technology in which crushed coal is mixed with limestone to neutralize the acidic sulfur compounds produced during combustion. It is a cleaner technology used by many large power plants in the United States, and is more efficient than traditional coal burning in that it produces more heat from a given amount of coal.

This, therefore, reduces carbon dioxide emissions per unit of electricity produced and minimizes the amount released into the atmosphere. Additionally, fluidized-bed combustion releases fewer sulfur and nitrogen oxides into the atmosphere as well.

4. What is the relationship of carbon capture and storage to atmospheric CO2?

Carbon capture and storage (CCS) technology removes carbon from fossil-fuel combustion and stores it underground. This contributes to an overall reduction in the release of carbon into the atmosphere.

Oil and Natural Gas 1. What are two examples of structural traps?

Structural traps are underground geologic structures that tend to trap any oil or natural gas present. They include upward folding of sedimentary rock strata and salt domes (underground columns of salt).

2. Why do estimates of Peak Oil vary?

Peak Oil is the point at which global oil production will reach a maximum rate; once that peak is passed, less and less oil will be removed each year. Some experts think that global oil production has already reached Peak Oil, while industry analysts are generally more optimistic. They think improving technology will allow us to extract more oil out of old oil fields and help us obtain oil from fields formerly unreachable.

3. What are three environmental problems associated with using oil and natural gas as energy resources?

There are a number of environmental problems associated with using oil and natural gas as energy resources. They include: (1) threats to environmentally sensitive areas caused by oil exploration and extraction; (2) the oil spills that can occur during extraction and/or

Chapter 11 transportation; (3) the large amounts of contaminated wastewater that results from removing natural gas from shale; (4) the increased global warming associated with CO2 emissions released when oil and natural gas are burned; and (5) acid deposition associated with the production of nitrogen oxides when oil is burned.

4. What is the controversy surrounding the Arctic National Wildlife Refuge?

Supporters of drilling in the Arctic National Wildlife Refuge say that development of domestic oil would improve the balance of trade and make us less dependent on foreign countries for our oil. Conservationists think oil exploration poses permanent threats to the delicate balance of nature in the Alaskan wilderness, in exchange for a temporary (and probably relatively small) oil supply.

Synfuels and Other Potential Fossil-Fuel Resources 1. How are different synfuels formed and extracted?

Synfuels are liquids or gaseous fuels that are synthesized from coal and other naturally occurring resources and used in place of oil or natural gas. Synfuels include tar sands, oil shales, gas hydrates, liquefied coal, and coal gas. Tar sands are heated underground with steam and then pumped out. Oil shales are crushed and heated to yield their oil, gas hydrates are extracted from deep underground porous rock in the frozen arctic tundra and deep-ocean sediments. Liquefied coal is produced from coal itself, and coal gas is produced from reacting coal with air and steam. Synfuels are more expensive to produce than oil and natural gas, but may become economically competitive as fuel prices rise.

2. How do the environmental problems associated with the use of synfuels compare to those of coal, oil, and natural gas?

Synfuels have many of the same undesirable effects as fossil fuels. Their combustion releases enormous quantities of CO2 and other pollutants into the atmosphere, thereby contributing to global warming and air pollution. Some synfuels, such as coal gas, require large amounts of water during production and are of limited usefulness in arid areas. In addition, enormously large areas of land would have to be surface mined to recover the fuel in tar sands and oil shales.

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Chapter 12 Renewable Energy and Nuclear Power Lecture Outline: I. Direct Solar Energy A. Solar energy is perpetually available; it varies in intensity depending on the latitude, season of the year, time of day, and cloud cover B. Technology exists to use solar energy directly, but initial costs associated with converting to solar power are high C. Heating buildings and water i. Visible light from the sun penetrates glass and warms the surfaces of objects inside, which in turn give off infrared radiation (invisible waves of heat); heat does not escape because infrared radiation cannot penetrate glass ii. In passive solar heating, solar energy heats buildings without the need for pumps or fans to distribute the heat; it can save as much as 50% of heating costs iii. In active solar heating, a series of collection devices mounted on a roof or in a field is used to gather solar energy; it is used primarily for heating water D. Solar thermal electric generation i. Solar thermal energy systems are more efficient than other solar technologies because they concentrate the sun’s energy ii. Solar thermal plants do not produce air pollution or contribute to acid rain or global warming E. Photovoltaic solar cells i. Photovoltaic solar cells are wafers or thin films of solid state material (i.e., silicon or gallium arsenide) that are treated with certain metals so that they generate electricity when they absorb solar energy 1. They currently provide about 5000MW of electricity worldwide (equivalent to 5 nuclear power plants) and account for about 0.15% of global electricity 2. They generate electricity with no pollution and minimal maintenance ii. There are a number of disadvantages to using PV solar cells 1. They are only about 15 to 18% efficient at converting solar energy to electricity 2. The number of solar panels for large-scale use requires a great deal of land II. Indirect Solar Energy A. Combustion of biomass, wind energy and hydropower are examples of indirect solar energy B. Biomass energy i. Biomass consists of such materials as wood, charcoal, fast-growing plant and algal crops, crop wastes, sawdust, wood chips, and animal wastes 1. Biomass fuel is renewable when it is used no faster than it is produced; it cannot replace fossil fuels

Chapter 12 2. At least half of the human population relies on biomass as their main source of energy; in the U.S. it only accounts for about 3% of total energy production ii. Animal wastes are often converted to biogas; a clean fuel that can be converted into methanol and ethanol C. Wind energy i. Wind energy is an indirect form of solar energy in which the radiant energy of the sun is transformed into mechanical energy; it is the world’s fastest growing source of energy ii. Wind power is cost-competitive with many forms of conventional energy ($.40 per kilowatt/hour in 1980 to $.04 in 2004) iii. The use of wind power does not cause major environmental problems (although bird deaths have been of concern) iv. Wind produces no waste and is a clean source of energy D. Hydropower i. Hydropower is the world’s main renewable source of electrical generation; it is more efficient than any other energy source in producing electricity ii. Hydropower generates approximately 19% of the world’s electricity; with nearly 2200 plants in the U.S. iii. About 97% of existing U.S. dams currently do not generate electricity iv. Impacts of dams 1. Dams change the natural flow of rivers, altering plant and animal habitats 2. In arid regions, increases in water loss (evaporation) and salinity are problems 3. Dams are expensive to build, but inexpensive to operate; they generally have limited life spans (50 to 200 years) E. Other indirect solar i. Ocean waves have the potential to turn turbines ii. Ocean temperature gradients could produce electricity to cool buildings (through Ocean Thermal Energy Conversion - OTEC) III. Other Renewable Energy Sources A. Geothermal energy i. Geothermal energy arises from the ancient heat within the Earth’s core, from friction where continental plates slide over one another, and from the decay of radioactive elements ii. Hydrothermal reservoirs contain hot water and possibly steam; they are tapped by drilling wells and the hot fluid is brought to the surface and used to supply heat directly or to generate electricity iii. The U.S. is the world’s largest producer of geothermal electricity; it is inexpensive and reliable iv. Geothermal energy from hot, dry rock is an expensive way to produce energy, but could greatly expand the extent and use of geothermal resources v. Heating and cooling buildings with geothermal energy

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Chapter 12 1. The Environmental Protection Agency (EPA) estimates that geothermal heat pumps (GHPs) are the most efficient heating systems available 2. They are two to three times more efficient than other heating methods and produce the lowest CO2 emissions B. Tidal Energy i. Water at high tide contains enormous amounts of potential energy; it can be captured with a dam across a bay or a turbine and converted into electricity ii. Total global production is only a few MWe, and is not expected to increase much in the near future IV. Introduction to Nuclear Processes A. Nuclear energy is the energy released by nuclear fission or fusion i. In the process of a nuclear reaction, a small amount of the mass of an atom is transformed into a large amount of energy (i.e., 1lb of uranium can release as much as energy as 7,300 metric tons of TNT) ii. Today there are 440 commercial nuclear reactors in 31 countries around the world iii. In nuclear bombs, the energy from many atomic fissions is release all at once, producing a tremendous surge of heat and power that destroys everything in its vicinity B. Atoms and Radioactivity i. Forms of a single element that differ in atomic mass are known as isotopes ii. The emission of energetic particles or rays from unstable atomic nuclei is called radioactive decay; each radioisotope has its own characteristic rate of decay C. Nuclear Fission i. The steps, from mining to disposal, of the uranium fuel used in nuclear power plants are collectively called the nuclear fuel cycle 1. Uranium ore contains three isotopes: U-238, U-235 (used in conventional fission reactions), U-234 2. Uranium ore (used in the nuclear reactors of conventional power plants) is a nonrenewable resource; it must be refined (enrichment) after mining to increase the concentration of fissionable U-235 ii. The fission of U-235 releases an enormous amount of heat, used to transform water into steam – the steam, in turn, is used to generate electricity iii. How electricity is produced from conventional nuclear fission 1. A typical nuclear power plant has four main parts: a. The reactor core – where fission occurs; it contains the fuel rods/fuel assemblies b. The steam generator – uses heat produced in the reactor core is to produce steam from liquid water c. The turbine – uses steam to generate electricity d. The condenser – cools the steam, converting it back to a liquid 2. Typically three water circuits are used to heat the water, convert the water to steam, and provide cool water to the condenser

Chapter 12 3. A huge, steel reactor vessel surrounds the reactor core; it is designed to prevent the accidental release of radiation into the environment 4. Additionally, the reactor vessel and the steam generator are placed in a containment building, providing an additional line of defense against accidental radiation leaks iv. Breeder reactors and mixed oxide fuel (MOX) for nuclear fission 1. Breeder nuclear fission converts U-238 into fissionable Pu-239 a. U-238 is not fissionable and is a waste product of conventional nuclear fission b. There are both safety and weapons proliferations concerns associated with breeder fission 2. Mixed Oxide Fuel (MOX) is a reactor fuel that contains a combination of uranium oxide and plutonium oxide a. For MOX reactions, spent fuel from standard uranium-based reactors is reprocessed b. MOX is now used in about 30 European reactors compared with the operation of only about 3 breeder reactors worldwide V. Pros and Cons of Nuclear Energy A. Nuclear energy has less of an immediate environmental impact than fossil fuels, it emits fewer pollutants into the atmosphere, and does not produce CO2 B. Nuclear energy generates dangerous radioactive wastes (spent fuel, coolant fluids, gases) that must be carefully stored and disposed of, it is not climate neutral (requiring substantial amounts of gasoline and diesel), and it is expensive to create and run plants C. Electricity deregulation caused several non-competitive nuclear power plants to shut down D. Can nuclear energy decrease our reliance on foreign oil? i. Oil generates only about 3% of the electricity in the U.S. ii. However, technological advances could change nuclear power’s potential contribution in the future (electric heat pumps, electric motor vehicles) VI. Safety Issues in Nuclear Power Plants A. Meltdowns could occur, releasing dangerous levels of radiation into the environment B. While the probability of a major accident is low, the public perception of the risk is high i. Nuclear power plants are involuntary and potentially catastrophic ii. People are distrustful of the nuclear industry iii. Consequences of an accident are drastic and life threatening (both short and long term) C. Three Mile Island (1979) i. Most serious nuclear reactor accident in the U.S. resulting from both human and design errors ii. A 50% meltdown of the reactor core took place; most of the radioactivity was contained in the containment building iii. No substantial damages or human casualties resulted; it took 12 years and 1 billion dollars to repair and reopen Three Mile Island

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VII.

D. Chernobyl (1986) i. The worst accident ever to occur at a nuclear power plant; one and/or two explosions ripped apart a nuclear reactor and expelled large quantities of radioactive material into the atmosphere ii. Significant amounts of radioisotopes spread across Europe; over 170,000 people had to permanently abandon their homes iii. Even 20 years later, much of the farmland and forests are so contaminated they cannot be used for more than a century, and local peoples still cannot drink the water or consume locally produced milk, fish, meat, fruits, or vegetables 1. Mothers do not nurse their babies 2. The number of attributable deaths is estimated between 10,000 and 100,000 3. Even small doses of ionizing radiation can be harmful; nearly 400,000 adults and more than 1 million children currently receive government aid for health problems related to Chernobyl E. The link between nuclear energy and nuclear weapons i. U-235 and P-239 are the two fuels commonly used in atomic fission weapons ii. 31 countries currently use nuclear energy to generate electricity; the possession of nuclear power plants gives these countries access to the fuel needed for nuclear weapons Radioactive wastes A. Radioactive wastes are classified as either low-level or high-level B. In 2004, US Federal Courts decided that any permanent burial site must meet EPA standards for the next one million years; potential sites include i. Stable rock formations deep in the ground ii. Mausoleums built in remote locations iii. Storage in Antarctic ice sheets iv. Burial in the seabed C. Radioactive wastes with relatively short half-lives i. U-235 may split in several ways, forming smaller radioactive atoms (i.e., krypton-85, strontium-90, cesium-137 – all with relatively short half-lives) ii. In 300 to 600 years they will have decayed to the point where they are safe D. High-level radioactive liquid waste i. These wastes are dangerously unstable and difficult to monitor; they must be converted to solid form before they can be stored ii. Solidifying liquid waste into solid glass or ceramic logs is known as vitrification E. Decommissioning nuclear power plants i. Nuclear power plants are licensed to operate for a maximum of 40 years ii. Three options exist when a nuclear power plant is closed: storage, entombment, and decommissioning 1. Storage – the utility company guards it for 50 to 100 years (allowing some radioactive materials to decay) until it is dismantled 2. Entombment – permanently encases the entire power plant in concrete for at least 1,000 years

Chapter 12 3. Decommission – dismantles an old nuclear power plant after it closes iii. Worldwide, 107 nuclear power plants were permanently retired as of 2004 (23 in the U.S.); 143 operational plants were 25 years or older VIII. Fusion: Nuclear Energy for the Future?

A. In fusion, two lighter atomic nuclei are brought together under conditions of high heat and pressure so that they combine, producing a larger nucleus (30mL of fusion fuel has the energy equivalent of 266,000L of gasoline) B. Isotopes of hydrogen are the fuel for fusion C. Supporters of nuclear energy view fusion as the best possible form of energy, both because its fuel (hydrogen) is available in virtually limitless supply and because it produces no high-level radioactive waste IX. The Future of Nuclear Power A. Standardizing a “new generation” of nuclear reactors designed to be 10 times safer than current reactors could lower costs for nuclear power B. Creating new fission reactors (i.e., PBMR – pebble-bed modular reactors) are potentially much safer than the ones in current operation C. More research and training is needed for nuclear engineers to safely design, build, and operate nuclear power plants

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In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Yucca Mountain and “The Facts”

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: The following four facts are evidence that Yucca Mountain should be opened as soon as possible.

1. Yucca Mountain is located on the Nevada Test Site, 100 miles north of the City Las Vegas 2. There is already enough high level nuclear waste to cover a football field 15 feet deep.

3. Terrorists could target un-stored nuclear waste 4. Recent earthquakes at Yucca Mountain have not been large enough to cause any damage at the site.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

Chapter 12 The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which, if either, provided the most compelling overall argument?

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class is comfortable with it.

Objectives:

Relate the pros and cons of permanent storage of high-level radioactive wastes at Yucca Mountain.

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Chapter 12

Instructor Notes for In-Class Activity 2 Title:

Why Not “Too Cheap To Meter”

Time: Materials: Handouts:

0 minutes prep; 15 – 25 minutes in class Internet access None

Procedures:

In the 1950’s, many nuclear power advocates believe that it would, in the future, provide the country with an energy source that would render electricity “too cheap to meter.” Some current advocates claim that this still should be true, but that regulations and public fears have pushed up expenses. Others argue that the economics of nuclear are inherent, and that it is not a particularly competitive energy source.

In groups of 3 – 5, have students explore these two arguments 1. What are the major arguments that the two sides use 2. Who are on the two sides?

3. How credible do you find the different sources of information?

4. Does it seem to you that nuclear could be less expensive that fossil fuels? Why or why not?

5. How much cheaper would nuclear have to be for electrical vehicles to replace gasoline powered vehicles?

Student See above Instructions: Specific Suggestions:

None

Objectives:

• •

Explain why nuclear power does not have much effect on U. S. oil needs.

Evaluate the economic viability of nuclear power

Chapter 12

Instructor Notes for In-Class Activity 3 Title:

Nuclear Materials on Campus

Time: Materials: Handouts:

5 – 20 minutes prep; full class session None None

Procedures:

Contact your campus environmental management personnel (the people who manage environmental affairs, not the department). Ask them to provide you a list of types and locations of nuclear materials on your campus or, if possible, request a tour of nuclear materials on campus.

Alternatively, ask your students to look for nuclear materials warnings around campus.

Have students discuss 1. What kinds of nuclear materials are being used?

2. What are they used for?

3. Are there any alternatives to these materials?

4. How much low-level nuclear waste is generated on your campus?

5. Where is this waste eventually taken?

Student See above Instructions: Specific Suggestions:

None

Objectives:

Describe non-energy and non-weapon uses of nuclear materials.

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Chapter 12

Instructor Notes for In-Class Activity 4 Title:

Nuclear Energy in the News

Time: Materials: Handouts:

5 – 20 minutes prep; full class session None None

Procedures:

Have the students check news articles, internet information and television ads and observe: 1. What nuclear energy issues are being presented 2. Are the issues relevant to their area 3. Are the issues accurate 4. What can they as students do about these issues 5. Are they increasing or decreasing After about a week of observance, have the students get together and discuss their finding.

You can limit or expand the search to the United States, different countries, the world or just the state the student represent, depending on the amount of information gathered.

Student See above Instructions: Specific Suggestions:

None

Objectives:

• •

Discuss nuclear energy and how it pertains to the individual and their need for energy.

Discuss the safety issues with nuclear energy.

Chapter 12

Instructor Notes for In-Class Activity 5 Title:

Nuclear Energy in the Cartoons

Time: Materials: Handouts:

5 – 20 minutes prep; full class session None None

Procedures:

Have the students go out and bring in at least 5 cartoons dealing with nuclear energy. Share the cartoons with the class. How do they portray nuclear energy?

Student See above Instructions: Specific Suggestions:

None

Objectives:

• •

Identify ways nuclear energy is perceived by the public.

Identify controversial topics when dealing with nuclear energy.

Instructor Notes for In-Class Activity 5 Title:

Designing a Nuclear Energy Program

Time: Materials: Handouts:

5 – 20 minutes prep; full class session None None

Procedures:

Because of the recent events around the disaster in Japan, many different

Student See above Instructions: Specific Suggestions:

None

Objectives:

• •

Identify ways nuclear energy is perceived by the public.

Identify controversial topics when dealing with nuclear energy.

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Chapter 12

Answers to Critical Thinking and Review End of Chapter Questions: 1. Explain the following statement: Unlike fossil fuels, solar energy is not resource-limited but is technology-limited.

Ans: Solar energy is different from fossil and nuclear fuels because it is perpetually available; we will run out of solar energy only when the sun's nuclear fire burns out. Solar energy is dispersed over Earth's entire surface rather than concentrated in highly localized areas, as are coal, oil, and uranium deposits. To make solar energy useful, we must collect it. The technological challenge is to collect and utilize it in a cost effective manner.

2. Biomass is considered an example of indirect solar energy because it is the result of photosynthesis. Given that plants are the organisms that photosynthesize, why are animal wastes considered biomass?

Ans: Biomass consists of such materials as wood, fast-growing plant and algal crops, crop wastes, sawdust and wood chips, and animal wastes. Biomass contains chemical energy that comes from the sun's radiant energy, which photosynthetic organisms use to form organic molecules. Animals that eat plants do not fully digest all the plant matter and the chemical energy stored in the animal dung can be used for fuel.

3. One advantage of the various forms of renewable energy, such as solar thermal and wind energy, is that they cause no net increase in atmospheric carbon dioxide. Is this true for biomass?

Why or why not?

Ans: As trees photosynthesize, they absorb atmospheric CO2 and lock it up in organic molecules that make up the body of the tree, thereby providing a carbon “sink.” Thus, if biomass is regenerated to replace the biomass used, there is no net contribution of CO2 to the atmosphere and to global warming. Unfortunately, in many areas people burn wood faster than they replant trees.

4. Some energy experts refer to the Great Plains states as “the Saudi Arabia of wind power.”

Explain what the reference means.

Ans: Harnessing wind energy is most profitable in rural areas that receive fairly continual winds, such as islands, coastal areas, mountain passes, and grasslands. In the continental United States, some of the best locations for large-scale electricity generation from wind energy are on the Great Plains. In fact, if we developed the wind energy in North Dakota, Texas, and Kansas to their full potential, we could supply more than enough electricity to meet the current needs of the entire United States.

5. Japan wishes to make use of solar power, but it does not have extensive tracts of land for building large solar power plants. Which solar technology do you think is best suited to Japan's needs? Why? Ans: Photovoltaic solar cells would be best suited for Japan’s needs. Thin-film PVs can be produced as flexible sheets that are incorporated into building materials, such as roofing shingles, tiles, and window glass. Unlike other solar technologies that require large areas of land, the thin-films can be incorporated into all sorts of building design. More than 120,000 Japanese homes have installed PV solar-energy roofing in the past few years.

Chapter 12 6. Why is potential wind energy in the United States greater than the potential for hydropower?

Ans: Areas such as the Great Plain of the United States have large potential for wind energy development. In contrast the US has already built dams at most of its potential site.

7. How does nuclear energy differ from chemical energy?

Ans: The energy released in combustion and other chemical reactions comes from changes in the chemical bonds that hold atoms together. Chemical bonds are associations between electrons, and ordinary chemical reactions involve the rearrangement of electrons. In contrast, nuclear energy involves changes in the nuclei of atoms; small amounts of matter from the nucleus are converted into large amounts of energy. Two different nuclear reactions release energy: fission and fusion.

8. What are the main steps in the nuclear fuel cycle? Is it a true cycle? Explain your answer.

Ans: The nuclear fuel cycle is all the processes involved in producing the fuel used in nuclear reactors and in disposing of radioactive wastes (or nuclear wastes). The steps include: mining, enrichment, fission reaction, and disposal. It is not a true cycle because nuclear energy is not a renewable resource.

9. Label the following diagram of a pressurized water reactor. What are the safety features?

INSERT Figure 12.17 Ans: See figure 12.17 for labels. A huge, steel reactor vessel surrounds the reactor core where fission occurs. The reactor vessel is a safety feature designed to prevent the accidental release of radiation into the environment. The reactor vessel and the steam generator are placed in a containment building, an additional line of defense against accidental radiation leaks.

Containment buildings have steel-reinforced concrete walls.

10. How is breeder nuclear fission different from conventional nuclear fission?

Ans: In breeder nuclear fission, U-238 is converted to plutonium, Pu-239, a human-made isotope that is fissionable. Some of the neutrons emitted in breeder nuclear fission produce additional plutonium from U-238. A breeder reactor thus makes more fissionable fuel than it uses. The fuel is then reprocessed to concentrate the Pu-239 for use as fuel.

Because it can use U-238, plutonium-based breeder fission can generate much larger quantities of energy from uranium ore than nuclear fission using U-235.

11. What is spent fuel?

Ans: Spent fuel is the used fuel elements that were irradiated in a nuclear reactor.

12. Should the air pollution (including greenhouse gases) produced from fossil fuels used to mine and refine uranium, build nuclear power plants, and transport nuclear wastes be attributed to nuclear energy? Why or why not?

Ans: Answers will vary.

13. How does the disposal of radioactive wastes pose technical problems? Political problems?

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Chapter 12 Ans: Many technical challenges exist in transporting waste safely, solidifying liquid waste and securing waste sites. Everyone agrees we need safe long term storage of nuclear waste, but when it comes to identifying a specific location for the waste, there is opposition, since people oppose having transportation or storage near where they work and live. There is political opposition for storage sites to be in anyone’s “backyard”.

14. What are the main arguments for and against the United States developing additional nuclear power plants to provide us with electricity over the next several decades? Which perspective do you find most convincing?

Ans: In an effort to promote nuclear energy, nuclear and utility executives have developed a plan that addresses the safety and economic issues associated with nuclear power. They envision building a series of “new generation” nuclear reactors designed to be 10 times safer than current reactors. Costs could be held in line by standardizing nuclear power plants rather than custombuilding each one. The new generation of nuclear power plants, though smaller, simpler in design, less expensive to build, and safer to operate, will still produce high-level radioactive wastes and have a potential link to nuclear weapons. Because of this there will always be opposition to nuclear power.

Answers to Review Questions Direct Solar Energy 1. What is active solar energy? Passive solar energy?

Active solar heating is a system of putting the sun’s energy to use in which a series of collectors absorb the solar energy, and pumps or fans distribute the collected heat. The most common collection device is a panel or plate of black metal, which absorbs the sun’s energy. Active solar energy is used primarily for heating water. Passive solar heating is a system of putting the sun’s energy to use without requiring mechanical devices to distribute the collected heat. It is primarily used to heat buildings without the need for pumps or fans to distribute the heat. Examples of passive solar heating designs include south-facing windows, heavily insulated north-facing walls, overhangs that block the summer sun, vents to allow hot air to escape, and thick adobe or stone walls.

2. What are the advantages of producing electricity by solar thermal energy? By photovoltaic (PV) solar cells?

Electricity produced by solar thermal energy is more efficient than other direct solar technologies. Additionally, it does not produce air pollution or contribute to acid rain or global climate change. Photovoltaic devices (i.e., solar cells) generate electricity with no pollution and minimal maintenance, but most are only about 10% to 15% efficient at converting solar energy to electricity.

Indirect Solar Energy

Chapter 12 1. What is biomass?

Biomass consists of plant material that is used as fuel. It is an example of indirect solar energy because it includes organic materials produced by photosynthesis.

2. What are advantages and disadvantages of using wind to produce electricity? Of using hydropower to produce electricity?

Harvesting wind energy to generate electricity has great potential because it is currently the most cost-competitive of all forms of solar energy, cost-competitive with many forms of conventional energy, and is the world’s fastest-growing source of energy. Wind produces no waste and is a clean source of energy; it produces no harmful emissions.

Additionally, the use of wind power does not cause major environmental problems, although reported bird and bat kills represent one concern. The biggest constraints on wind are cost and public resistance.

Hydropower is the world’s main renewable source of electrical generation, producing about the same amount of electricity as do the world’s nuclear power plants. It is more efficient than any other energy source in producing electricity; about 90% of available hydropower energy is converted into electricity. Unfortunately, dams cost a great deal to build and only have a life span of 50 to 200 years. Moreover, most sites suitable for traditional hydropower plants are already in use. Many environmental and social problems are also associated with hydropower. They include ecological destruction upstream and downstream, increased evaporation of water, disease and pollution, displacement of people, and inundation of farmland.

Other Renewable Energy Sources 1. What are the pros and cons of using geothermal energy to produce electricity? Or using tidal power?

Geothermal energy is the use of energy from the Earth’s interior for either space heating or the generation of electricity. Geothermal energy is considered environmentally benign compared to conventional fossil-fuel-based energy technologies because it emits only a fraction of the air pollutants. The most common environmental hazard associated with geothermal energy is the emission of hydrogen sulfide (H2S) gas. A lesser concern is that the surrounding land may subside as the water from hot springs and their connecting underground reservoirs is removed. An additional drawback, is that geothermal heat pumps (commonly used to heat buildings) often have high installation costs. Benefits, however, include low operating costs and high efficiency. Furthermore, while the amount of geothermal energy is enormous, it is difficult to extract, and will therefore most likely not compete with wind, hydropower, or solar energy.

Tidal energy is a form of renewable energy that relies on the ebb and flow of the tides to generate electricity. Water at high tide contains an enormous amount of potential energy as compared to low tide. This energy can be captured and converted into electricity; however, it only occurs twice each day, and is typically not substantial unless in certain

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Chapter 12 coastal regions with narrow bays. Tidal energy is currently used on a very limited scale, and is not expected to increase much in the near future.

Nuclear Power 1. What is the difference between chemical energy and nuclear energy?

In ordinary chemical reactions, the atoms of one element do not change into atoms of another element, nor does any of their mass (matter) change into energy. In contrast, nuclear energy is the energy released by nuclear fission or fusion. In nuclear energy, small amounts of matter from atomic nuclei are converted into large amounts of energy.

2. What is the nuclear fuel cycle?

The nuclear fuel cycle includes the processes involved in producing the fuel used in nuclear reactors and in disposing of radioactive wastes (or nuclear wastes). Enrichment, which is part of the nuclear fuel cycle, is the process by which uranium ore is refined after mining to increase the concentration of fissionable U-235.

3. How does a nuclear reactor produce electricity?

A nuclear reactor is a device that initiates and maintains a controlled nuclear fission chain reaction to produce energy for electricity.

Pros and Cons of Nuclear Energy 1. In generating electricity, how do the environmental effects of coal combustion and conventional nuclear fission compare?

Nuclear power can serve as an alternative to electricity generation from coal (which contributes to greenhouse gases to the atmosphere). One reason proponents of nuclear energy argue for its widespread adoption is that it has less of an environmental impact than fossil fuels (i.e., coal). Nuclear energy emits few pollutants into the atmosphere and provides power without producing carbon dioxide. However, it generates highly radioactive waste such as spent fuel. Safety is a concern at nuclear power plants.

2. What were the effects of the nuclear power plant accidents at Three Mile Island in Pennsylvania, Chernobyl in Ukraine, and Fukushima Daiichi in Japan?

Three Mile Island was the most serious nuclear reactor accident in the United States. It occurred in 1979 at the Three Mile Island power plant in Pennsylvania. Both human and design errors were responsible for this partial meltdown of the reactor core. Luckily the containment building kept almost all the radioactivity from escaping. Three Mile Island elevated public apprehension about nuclear power, and prompted construction delays and

Chapter 12 cancellations of several new nuclear power plants across the United States. It took 12 years and $1 billion to repair and reopen the second (undamaged) reactor at Three Mile Island.

The worst accident to ever occur at a nuclear power plant took place in 1986 at the Chernobyl plant, located in the former Soviet Union (now Ukraine). A range of factors contributed to the accident (violations of safety rules, flawed design, inferior construction, and operator errors), where one or possibly two explosions ripped apart a nuclear reactor and expelled large quantities of radioactive material into the atmosphere.

This resulted in widespread environmental pollution and serious local contamination.

The Chernobyl accident affected and will continue to affect many nations. Over 100,000 residents in a 30-km radius around the plant were quickly evacuated and resettled. The power station was cleaned up and contained, highly radioactive soil was removed, and nearby buildings and roads were scrubbed down to remove radioactive dust. Many longterm problems have resulted from this nuclear meltdown: farmland and forest contamination led to reduced agricultural production; water remains contaminated; local produce remains contaminated; and high rates of various cancers in nearby inhabitants.

Nearly 400,000 adults and more than 1 million children currently receive government aid for health problems related to Chernobyl.

On March 11, 2011, a magnitude 9.0 earthquake struck Japan. A subsequent tsunami caused severe damage to the Fukushima Daiichi nuclear power station. It disrupted both the normal power supply and the two back-up systems (generators and batteries) that pump cooling water to the six reactors. Without cooling water, both the reactors and spent fuel rods are at risk of overheating and/or melting down. Radioactivity has been released into the environment, mostly through groundwater contamination. The extent of an accident remains unknown at this point, but includes an explosion, deaths, evacuations, and extensive contamination. It is likely that the entire facility will be not only inoperable but unsafe to humans for decades or centuries.

3. What is the link between nuclear energy that produces electricity and nuclear weapons?

Fission is involved in both the production of electricity by nuclear energy and in the destructive power of nuclear weapons. However, having nuclear power facilities alone does not provide the materials needed for nuclear weapons; it only provides a country with materials needed to produce enriched uranium or plutonium for weapons. Uranium235 and plutonium-239 are the two fuels commonly used in atomic fission weapons, but must be enriched substantially before they can be used for weapons.

Radioactive Wastes 1. What is low-level radioactive waste, and how is it disposed of? What is high-level radioactive waste, and how is it currently stored?

Low-level radioactive wastes are radioactive solids, liquids, or gases that give off small amounts of ionizing radiation. They are produced by nuclear power plants, university research labs, nuclear medicine departments in hospitals, and industries. Low-level

208

Chapter 12 radioactive wastes are disposed of in three designated nuclear dump sites throughout the country (Washington State, South Carolina, and Utah).

High-level radioactive wastes are solids, liquids, or gases that initially give off large amounts of ionizing radiation. They are produced during nuclear fission and the reprocessing of spent fuel. Geological burial and deep underground storage are the best solutions for this type of waste. However, an appropriate storage site must have geological stability and little or no water flowing nearby. Currently, the United States has no designated waste storage location such as this. For the mean time, most high-level radioactive waste is stored in huge indoor pools of water at the respective nuclear power plants. Some nuclear waste is then transferred from on-site wet storage to dry cask storage, large cylinders of concrete and steel that hold 10 or more metric tons of highlevel waste.

2. What are some of the advantages of storing high-level radioactive waste at Yucca Mountain? What are some of the disadvantages?

Advantages to storing high-level radioactive waste at Yucca Mountain include the fact that it is safe from volcanic eruptions and earthquakes, and its capacity to take all existing spent fuel plus the amount of spent fuel that will be produced until about 2025.

Disadvantages include public opposition and the fact that while the possibility of a volcanic eruption is considered remote, the site still lays near a volcano and active earthquake fault lines (90 miles away). Additionally, the transportation of high-level wastes from nuclear reactors and weapons sites is a major concern; the average shipment would travel 2300 miles through many states.

The Future of Nuclear Power 1. How will future nuclear power reactors differ from current plants?

The next generation of nuclear power plants is expected to be smaller, simpler, safer, and more cost-effective than the reactors currently in use around the world. The NRC has already approved four new advanced reactor designs, and more are proposed.

Chapter 13 Water: A Limited Resource A. Properties of Water a. Composed of 2 Hydrogen and 1 Oxygen b. Exists as a solid, liquid or gas c. High heat capacity d. Is polar e. Forms hydrogen bond between 2 water molecules i. Hydrogen bonds define water’s physical properties f. Water is never completely pure in nature-contains dissolved gasses from the atmosphere and dissolved mineral salts g. Many pollutants dissolve in water B. Hydrologic Cycle and our Supply of Fresh Water a. Water continuously circulates through the environment, from the ocean to the atmosphere to the land and back to the ocean. b. Only 2.5% of water on earth is fresh water and most of that is leaving only %0. 5 available fresh water c. Surface Water- Precipitation that remains on the surface and does not seep into the soil d. Runoff- Movement of surface water to lakes, rivers, etc. e. Watershed (drainage basin)- Land area that delivers water into a stream or river system f. Groundwater- Freshwater under the earth’s surface stored in aquifers g. Aquifer- Underground cavers and porous layers of sand, gravel and rock in which groundwater is stored C. Water Use and Resource Problems a. To much water i. Flooding both natural and human induced ii. Modern floods are highly destructive because humans have removed water-absorbing plant cover from the soil and construct buildings on floodplains iii. Floodplain- Area bordering a river channel that has the potential to flood b. To Little Water i. Typically found in arid land ii. Drought, overdrawing water for irrigation iii. Aquifer depletion causes subsidence and sinkholes iv. Saltwater intrusion-The movement of seawater into a freshwater aquifer located near the coast-caused by aquifer depletion D. Water Problems In US and Canada a. US has a plentiful supply of fresh water as compared to other countries b. Many areas of the US have sever shortages due to geographic location (desert) and seasonal variations in weather

Chapter 13 c. Water shortages a severe in the West and Southwest US so water is diverted and transferred via aqueducts d. Mono Lake, CA- Rivers and streams that once fed this lake are diverted to Los Angles. The lake is becoming highly saline. e. Colorado River Basin- Provides water for more then 30 million people.

Have numerous dams for hydropower. Colorado river no longer reaches the Ocean as a result of its waters diversions. f. Conservation-based Pricing- Water supply pricing structure that rewards customers for using less water. These often come in the form of low process for water uses up to some level and stepped-up prices as use increases g. Groundwater i. Aquifer depletion ii. Ogallala Aquifer- in the high planes of the US. Has the largest groundwater deposit in the world. Water is being withdrawn from it faster than nature can replace it.

E. Global Water Problems a. Amount of freshwater on the planet can meet human needs but it is unevenly distributed and some places lack stable runoff i. Stable Runoff- The share of runoff from precipitation that can be depended on every month b. Water and Climate Change i. Climate change affects the type and distribution of precipitation ii. Potential issues- reduced snowfall will impact water resources downstream and sea level rise will cause saltwater intrusion into drinking water supplies c. Drinking water Problems i. Many developing countries have insufficient water to meet drinking and household needs d. Population Growth i. Increase in population means an increase in the freshwater drinking requirements ii. Limits drinking water available iii. Limits water available for agriculture e. Sharing Water Resources Among Countries i. Rhine River Basin 1. Countries upstream discharged pollutants into river 2. Countries downstream had to pay to clean the water before they could drink ii. Aral Sea 1. Water diversion for irrigation has caused sea to become to saline f. Potential Volatile International Water Situations i. Jordan River ii. Nile River F. Water Management

Chapter 13 a. Maine goal is to provide sustainable supply of high-quality water with: i. Dams and Reservoirs 1. Ensure year round supply of water with regulated flow 2. Generate electricity 3. Provide recreational activities 4. Alter the ecosystem 5. Reduce sediment load ii. Water Diversion Projects 1. Waters are diverted to areas that are deficient 2. Much of Southern CA receives its water supply from diverted water from Northern CA. 3. Controversial and expensive iii. Desalinization 1. Removal of salt from ocean or brackish water 2. Can be done by distillation or reverse osmosis 3. Very expensive G. Water Conservation a. Reducing agricultural waste i. Agriculture is inefficient with water ii. Microirrigation- irrigation that conserves water by piping it to crops through sealed systems, Also called drip irrigation iii. Low energy precision application irrigation LEPA iv. Geographic information systems irrigation GIS b. Reducing Industrial Waste i. Stricter laws provide incentive to conserve water ii. Water scarcity encourages further industrial recycling c. Reducing Municipal Water Waste i. Gray water- Water that has already been used for relatively nonpolluting purpose such as showers, dishwashing and laundry. Can be used to flush toilets, water plants or car washing ii. Water saving household fixtures iii. Government incentives iv. Collecting and storing rainwater

Chapter 13

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Alternative Plants on Campus

Time: Materials: Handouts:

10 minutes prep; full class period Internet access and campus map.

Copies of Campus Map

Procedures:

Tour campus; if class is large enough, divide into groups to try to cover as much of the campus area as possible. List and plot on the map the plants you find. Which of these are decorative and which are functional (e.g. lawns that are used by students…although you are welcome to debate the relevance of this). Return to class and research: • Which of these plants require water, and how much?

• What alternatives to these plants are native to your area?

• What would be the aesthetic impact of changing to native or low water use plants?

• What would be the practical impacts of the change?

• How long would it take your campus to recoup the costs of redoing the landscaping?

Student See above Instructions: Specific None Suggestions: Objectives:

• • •

Define sustainable water use Describe landscape water requirements Give examples of water conservation

Chapter 13

Instructor Notes for In-Class Activity 2 Title:

Estimating Individual Water Use

Time: Materials: Handouts:

5 minutes prep; 20 minutes in class None Water Use Log

Procedures:

Have students track their personal water use for one or more days. Have them • calculate total water use, and compare this number to the minimum suggested by the World Health Organization • estimate how much water they could save by making minor lifestyle changes • estimate how much water they could save by making major lifestyle changes • discuss which of these would have aesthetic, financial and / or health implications

Student Complete the water log as assigned by your instructor.

Instructions: Estimate your average daily water use Come up with a list of changes you could make to your daily routine that would reduce your water consumptions In groups of 3 – 4, discuss the impacts of these changes on your lifestyle • Which would require major changes?

• Which would require minor changes?

• Which changes would be aesthetic?

• Which changes would entail financial costs?

• Would any of these changes have health impacts? Explain.

Specific Suggestions:

None

Objectives:

• •

Contrast water use in highly developed and developing countries Give examples of water conservation opportunities

Chapter 13 In-Class Activity 2: Handout Use this form to log your daily water use. In some cases, you will need to do some research to find out how much water is being used. Most toilets, for example, have “gallons per flush” listed. Your local water agency or hardware store should be able to tell you how much water can go through a sink pipe in a given amount of time, or you may be able to estimate this yourself.

Category

Tips

Bathroom Shower time in shower (include the time you let it run to heat up) x shower flow rate Loads of laundry loads per day x water per load Sink use washing hands, brushing teeth, other Toilet flushes see tank for information Kitchen Dishwashing By hand and dishwasher Cooking Other cleaning Drinking Household Cleaning Divide by number of people in household!

Plants Pets Drinking water and cleanup Yard Cleaning Plant maintenance Away from Home Restaurants Drinking, food prep, cleanup Toilet / wash-up Drinks Most sodas and alcoholic drinks are mostly water Other

Amount (gallons)

Chapter 13

Instructor Notes for In-Class Activity 3 Title:

Three Gorges Dam Debate

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: The Chinese government should stop filling and dismantle the Three Gorges Dam Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions: Specific The instructor is likely to have to serve as a facilitator or moderator from Suggestions: time to time

Chapter 13 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Contrast the benefits and drawbacks of dams and reservoirs

Chapter 13

Instructor Notes for In-Class Activity 4 Title:

Water Around the World

Time: Materials: Handouts:

5 – 20 minutes prep; full class session None None

Procedures:

Look over Chapter 9 in your book and have the students look at the countries they chose for population.

Each student and their population analyze the water problems for that population.

Some questions to consider: The more people the more water problems?

What is the quality of water in the chosen populations?

How is the drinking water differ in different populations?

Is there a water shortage with different populations?

How can the population your chose change the quality of their drinking water?

Is it up to them or is there a strong government who regulates the water quality?

When each student in their group evaluates their population and water they will report to the class.

Student See above Instructions: Specific Suggestions:

None

Objectives:

Briefly describe each of the following international water problems: drinking water problems, population growth and water problems, and the potentially volatile international situation over water rights.

Answers to Critical Thinking and Review End of Chapter Questions: 1. Explain why the poor in many countries have to pay more for their water than do the wealthy.

Ans: All of the same system components exist in poor and wealthy countries: water must be cleaned, transported, bought and sold. However, there is little money to develop and maintain the infrastructure, so water from pipes is sporadic, if available at all. When the water does run, it might be contaminated from holes in the pipes in contact with human waste. An alternative is to buy water from a vendor who comes by with tanks or jugs of water. But these freelance water dealers are unpredictable, the quality of the water unknown, and a different price might be negotiated each day. A consumer might boil the

Chapter 13 water to kill off biological contaminants, but this in turn requires energy, which is also in limited supply and expensive 2. What does this diagram represent? Explain how this process affects the properties of water.

INSERT FIGURE 13.2 Ans: Polarity causes hydrogen bonds (represented by dashed lines) to form between the positive areas of one water molecule and the negative areas of others.

Each water molecule forms up to four hydrogen bonds with other water molecules.

Hydrogen bonds are the basis for many of water's physical properties, including its high melting/freezing point (0°C, 32°F) and high boiling point (100°C, 212°F).

3. Describe several threats to surface water and groundwater supplies Ans: Water pollution is the contamination of water bodies. Water pollution occurs when pollutants are discharged directly or indirectly into water bodies. Point source water pollution refers to contaminants that enter a waterway from a single, identifiable source.

Non-point source pollution refers to diffuse contamination that does not originate from a single discrete source.

Surface water is water in a river, lake or fresh wetland. Surface water threats include contamination such as agricultural runoff, lawn chemicals, soil erosion, and storm water runoff.

Groundwater or sub-surface water is fresh water located in the pore space of soil and rocks. Groundwater also includes water that is flowing within aquifers below the water table. Groundwater is susceptible to contamination from sources that may not directly affect surface water bodies. A spill or the ongoing release of chemical contamination into soil could potentially contaminate the aquifer below forming a toxic plume. Ground water is also highly susceptible to over-use resulting in a removal of water from the aquifer faster than it is being replaced. If this occurs along the coastline seawater intrusion into the freshwater aquifer could occur.

4. Discuss the dissolving ability of water as it relates to ocean salinity and to water pollution.

Ans: Water is often called the universal solvent because many materials dissolve in water. In nature, water is never completely pure because it contains dissolved gases from the atmosphere and dissolved mineral salts from land. Seawater contains a variety of dissolved salts, including sodium chloride, magnesium chloride, magnesium sulfate, calcium sulfate, and potassium chloride. Water's dissolving ability has a major drawback: many of the substances that dissolve in water cause water pollution.

5. Should we allow housing on the flood plain of a river? Should taxpayers provide federal disaster assistance for those who choose to live on flood plains? Explain your answers.

Ans: Answers will vary.

Chapter 13 6. Explain the relationship between global climate change and local availability of fresh water.

Ans: Climate change is expected to play an important role in future freshwater availability. Climate change driven by increases in carbon dioxide and other greenhouse gases impacts more than just global temperatures. It has broad, systemic impacts, including the amount, type and distribution of precipitation. Precipitation is expected to increase in some areas while it drops in others. Changes in rainfall may lead to non-linear changes in available surface water since runoff is influenced by geological factors, such as permeability, and biological factors, such as amount of vegetation.

7. Are water supply problems due to too many people or too much consumption per person in the United States? In developing countries? Explain the differences (if any).

Ans: Compared with many countries the United States has a plentiful supply of fresh water. However despite the abundance of freshwater in the United States many areas have severe water shortages because of geographical and seasonal variations. Water issues in developed countries normally are the result of over consumption by the general population. The typical American uses about 90 gal of water each day. In contrast water supply problems in developing countries are usually due to population pressures. For example Asia has the world’s largest available water resource – 36% of the earth’s total but is home to 60% of the world’s population. The United nation development Program has proposed that access to at least 5.2 gal of safe water per day per person should be considered a basic human right.

8. Briefly describe the complexity of international water use, using the Rhine River, the Aral Sea or Iraq as an example.

Ans: The drainage basin for the Rhine River in Europe is in five highly developed and densely populated countries-Switzerland, Germany, France, Luxembourg, and the Netherlands. Traditionally, Switzerland, Germany, and France used water from the Rhine for industrial purposes and then discharged polluted water back into the river. The Dutch then had to clean up the water so they could drink it. Today, these countries recognize that international cooperation is essential to conserve and protect the supply and quality of the Rhine River.

In the 1950s, the Soviet Union began diverting water from the Amu Darya and the Syr Darya, the two rivers that feed into the Aral Sea, to irrigate desert areas surrounding the lake. By the early 1980s, irrigation for growing cotton had diverted more than 95% of the Aral Sea's inflow. Much of its biological diversity has disappeared-all 24 fish species originally found there are gone. Immediately following the breakup of the Soviet Union in 1991, plans to save the Aral Sea faltered as responsibility for its rescue shifted from Moscow to the five central Asian countries that share the Aral Basin: Uzbekistan, Kazakhstan, Kyrgyzstan, Turkmenistan, and Tajikistan. In 1994 the five nations established a fund to prevent the complete disappearance of the Aral Sea. The World

Chapter 13 Bank and the U.N. Environment Program approved a grant to the five countries to help address the environmental problems of the area.

In Iraq, the headwaters of both the Tigris and the Euphrates Rivers originate outside the country's borders. While current conflicts in Iraq overshadow the water issue, shortages in both quality and quantity of water remain an internal challenge. Water supply will continue to influence Iraq's relations with neighboring countries, especially those upstream, including Turkey, Syria, Jordan, and Saudi Arabia as well as Iran, with which Iraq has had armed conflicts for decades.

9. Explain how water resource problems might contribute to economic or political instability.

Ans: Consumers need to have a reliable source of water at a predictable cost. Different parts of the system need to be managed by experts, who can be held accountable. If countries fail to do this and water prices fluctuate greatly it could mean economic hardship for poor people. If managers are not held accountable mistrust of the political system may ensue. In addition, severe water shortages may lead to migrations of people to wetter regions.

10. How is water used in agriculture? Discuss two ways to use agricultural water more sustainably.

Ans: Irrigation generally makes inefficient use of water. Traditional irrigation methods practiced for more than 5000 years involve flooding the land or diverting water to fields through open channels. One of the most important innovations in agricultural water conservation is microirrigation also called drip or trickle irrigation, in which pipes with tiny holes bored in them convey water directly to individual plants. Microirrigation substantially reduces the water needed to irrigate crops. Another important water-saving measure in irrigation is the use of lasers to level fields, allowing a more even water distribution.

11. What are some of the advantages of dams? The disadvantages?

Ans: A dam is a barrier that impounds water. Dams generally serve the primary purpose of retaining water. Dams can be used to generate power(hydroelectric), as a supply of water, to stabilize water flow for agricultural and irrigation purposes, flood prevention, recreation, land reclamation (dykes) and navigation. Unfortunately dams can harm nature and wildlife (especially fish and rare species) and have an impact on the geology of an area. Water that is released from a reservoir usually contains very little suspended sediment and this can lead to scouring of river beds and loss of riverbanks. Older dams often lack fish ladders which can prevent fish from moving up stream to their natural breeding grounds resulting in failure of breeding cylces.

12. Describe several types of irrigation that reduces water use

Chapter 13

Ans: Irrigation is the artificial application of water to the land or soil to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of soils. Drip irrigation also known as trickle irrigation is one of the most water-efficient methods of irrigation. In drip irrigation tiny holes are bored into pipes that convey water to individual plants. Drip irrigation can reduce the amount of water need to irrigate the crops by 4060% compared to center-pivot irrigation or flood irrigation. A newer form of irrigation combines low-energy precision application with geographic information system(LEPA).

LEPA involves dragging hoses across fields in a computer controlled pattern. Water is only released when and where it is needed.

13. Which industries consume the most water? Discuss one way to use industrial water more sustainably.

Ans: In the United States, five major industries-chemical products, paper and pulp, petroleum and coal, primary metals, and food processing-consume almost 90% of industrial water. Water use by these industries does not include water used for cooling purposes. Stricter pollution control laws provide some incentive for industries to conserve water. Industries usually recapture, purify, and reuse water to reduce their water use and their water treatment costs. It is likely that water scarcity, in addition to more stringent pollution control requirements, will encourage further industrial recycling. The potential for industries to conserve water by recycling is enormous.

14. One strategy for inland cities like Denver or Phoenix to increase their water supply would be to fund desalinization plants hundreds of miles away in California and trade that water for an increased share of Colorado River water. Explain why this might be a cost-effective solution, and discuss whether it seems like a fair or politically viable approach.

Ans: Answers will vary.

15. Imagine you are a water manager for a southwestern metropolitan district with a severe water shortage. What strategies would you use to develop a sustainable water supply? Why would a systems perspective help you achieve this?

Ans: Management techniques may include any of the following. Dams ensure a yearround supply of water in areas with seasonal precipitation or snowmelt. Dams confine water in reservoirs, from which the flow is regulated. One way to increase the natural supply of water to a particular area is to divert water from areas where it is in plentiful supply by pumping water through a system of aqueducts. Seawater and salty groundwater are made fit to drink through desalinization (or desalination). There are two major approaches to desalinization: distillation systems and membrane/filtration systems. From a systems perspective another important approach would be water conservation and water efficiency measures.

16. Develop a brief water conservation plan for your own personal daily use.

Ans: Answers will vary.

Chapter 13

Answers to Review Questions The Importance of Water 1. How do hydrogen bonds form between adjacent water molecules?

Water molecules are polar. That is, one end of a water molecule has a positive charge and the other end has a negative charge. It is this polarity that attracts the negative end of one water molecule to the positive end of another, forming a hydrogen bond between the two.

2. What is surface water? Groundwater?

Surface water comes from precipitation that remains on the surface of the land as runoff; it does not seep down through soil. Groundwater is the supply of fresh water under the Earth’s surface; it is stored in underground aquifers.

Water Use and Resource Problems 1. Which human activity is responsible for more than 70% of global water consumption?

Agricultural irrigation accounts for approximately 71% of the world’s total water consumption.

2. How has development along the upper Mississippi River exacerbated property damage during periods of flooding?

During periods of flooding, development along the upper Mississippi River exacerbated property damage because many residents of this area built their homes on nearby floodplains and drained wetlands; both of which have a natural ability to help moderate floods.

3. What are some of the problems associated with overdrawing surface water? With aquifer depletion?

When surface water is overdrawn, the organisms in freshwater ecosystems suffer.

Also, natural wetlands dry up and estuaries become saltier. Aquifer depletion is the removal of groundwater faster than it can be recharged by precipitation or melting snow. Aquifer depletion from porous rocks can cause subsidence, or sinking land. Aquifer depletion can also cause saltwater intrusion of freshwater aquifers near the coast.

Water Problems in the United States and Canada 1. Which U. S. regions have the most severe water-scarcity problems?

Water problems are particularly severe in the American West and Southwest (i.e., arid or semiarid regions).

Global Water Problems

Chapter 13 1. What is the relationship between climate change and global water problems?

Climate change is expected to lead to changes in the amount, type, and distribution of precipitation that, due to biological and geological factors, many have severe impacts in some areas. These changes may lead to abrupt changes in the availability of surface water worldwide. Additionally, snowfall may be reduced in some areas and saltwater intrusion from sea-level rise could result.

2. Which international water problems have been most amenable to management? Least amenable?

Nearly 260 of the world’s major watershed are shared between at least two nations. Therefore, international cooperation is required to manage rivers that cross international borders. International water problems that have been most amenable to management include those of the Rhine River Basin and the Aral Sea. International water problems that have been least amenable to management include the Mekong River basin, the Indus River basin, the Jordan River and the Nile River basin.

Water Management 1. What is sustainable water use?

Sustainable water use is the use of water resources in a fashion that does not harm the essential functions of the hydrologic cycle or the ecosystems on which present and future humans depend.

2. What are some major problems and solutions associated with dams on the Columbia River?

There are over 100 dams within the Columbia River system, 19 are major generators of hydroelectric power. These dams have adversely affected fish populations, particularly salmon, by preventing them to return to their place of birth in order to reproduce and die. To protect some of the remaining natural salmon habitats, several streams in the Columbia River system are off-limits for dam development. Additionally, underwater screens and passages are being installed at dams to steer smolts away from the turbine blades. Trucks and barges have even been employed to transport some of the young fish around dams, while others swim safely over the dam because the electrical generators are periodically turned off to allow passage. Lastly, many dams have fish ladders to allow some of the adult salmon to bypass the dams and continue their upstream migration.

3. What is desalinization? Reverse osmosis?

Desalinization is the removal of salt from ocean or brackish water. Reverse osmosis is a membrane/filtration method of desalinization in which salt water is forced through a membrane permeable to water but not to salt.

Chapter 13

Water Conservation 1. What are the most promising water conservation measures for agriculture, industry, and individual homes and businesses?

Promising water conservation measures for agriculture includes both microirrigation (aka, drip or trickle irrigation) and the use of lasers to allow more even water distributions in fields. Moreover, the combination of low-energy precision application (LEPA) irrigation and geographic information systems (GIS) have allowed water to be released only when and where it is needed.

Promising water conservation measures for industry include recapturing, purifying, and reusing water. Additionally, implementing water efficiency projects within industries can also result in substantial water savings.

Promising water conservation measures for individual homes and businesses also include recycling and reuse. For example, using gray water to flush toilets, wash the car, or water the lawn can dramatically reduce water use.

Chapter 14 Soil Resources Lecture Outline: I. What is soil?

A. Soil is the relatively thin surface layer of Earth’s crust consisting of minerals and organic matter modified by the natural actions of weather, wind, water, and organisms B. Soil-forming factors i. Soil is formed from parent material, rock that is slowly broken down, or fragmented, into smaller and smaller particles by biological, chemical, and physical weathering processes in nature 1. This is a continuous process that can take thousands of years 2. Organisms and climate both play essential roles in weathering ii. Topography is also involved in soil formation C. Soil composition i. The soil system is composed of four distinct parts: mineral particles (45%), organic matter (5%), water (25%), and air (25%) 1. Humus is a mix of many organic compounds, it helps to bind to nutrient mineral ions and holds water in the soil 2. Both soil water and soil air are necessary to produce a moist, aerated soil that sustains plants and other soil-dwelling organisms D. Soil horizons i. Soils are organized into distinctive horizontal layers called soil horizons ii. A soil profile is a vertical section from surface to parent material, showing the soil horizons 1. O-horizon – uppermost layer, rich in organic material 2. A-horizon – topsoil, dark and rich in accumulated organic matter and humus 3. E-horizon – heavily leached, sometimes between the A and B-horizons 4. B-horizon – zone of accumulation in which nutrient minerals that leached out of the topsoil and litter accumulate 5. C-horizon – beneath the B-horizon, contains weathered pieces of rock; it is beneath the extent of most roots and is often saturated with groundwater E. Soil organisms i. Soil bacteria often number in the hundreds of millions per gram of soil 1. Scientists have identified about 170,000 species of soil organisms 2. They provide several essential ecosystem services a. Maintain soil fertility b. Prevent soil erosion c. Break down toxic materials d. Cleanse water

Chapter 14 ii. Worms deposit castings on the soil surface, cycling nutrient minerals and aerating the soil; ants also aerate the soil and aid in plant reproduction iii. Mycorrhizae help plants absorb adequate amounts of essential nutrient minerals from the soil F. Nutrient cycling helps cycle nutrient minerals from the soil to organisms and back again to the soil II. Soil Properties and Major Soil Types A. Texture and acidity are two parameters that characterize soils i. Texture refers to the relative proportions of different-sized inorganic mineral particles of sand, silt, and clay in soil ii. A loam (ideal agricultural soil) has an optimum combination of different soil particle sizes B. Soil acidity i. Most soils range between a pH of 4 and 8; optimum soil pH for plant growth is 6 to 7 ii. Soil pH greatly affects the leaching of nutrient minerals iii. Soil pH affects plants partly because the solubility of certain nutrient minerals varies with differences in pH C. Major soil groups i. Soil taxonomy classifies soils into 12 distinctive orders and many subsequent series using color, depth, mineral content, acidity, pore space, etc. ii. The U.S. alone has as many as 19,000 soil series iii. Five common soil orders include 1. Spodosols (coniferous forests) 2. Alfisols (temperate deciduous forests) 3. Mollisols (temperate, semiarid grasslands) 4. Aridisols (arid regions) 5. Oxisols (tropical and subtropical areas) III. Soil Problems A. Sustainable soil use is the wise use of soil resources, without a reduction in the amount or fertility of soil, so that it is productive for future generations B. Soil erosion i. Water, wind, ice, and other agents promote soil erosion ii. Erosion limits the growth of plants, causes a loss of fertility, and reduces the amount of soil in an area iii. Humans often accelerate soil erosion with poor soil management practices iv. Soil erosion results in an annual loss of as much as 75 billion metric tons of topsoil around the world C. Nutrient mineral depletion i. When organisms die and microorganisms decompose them, the essential nutrient minerals are released into the soil ii. Mineral depletion in tropical rainforest soils 1. Soils are somewhat nutrient-poor because the nutrient minerals are stored primarily in vegetation 2. When the forest is cleared, its efficient nutrient cycling is disrupted

Chapter 14 D. Soil salinization often occurs in arid and semiarid regions due to the high natural concentrations of inorganic compounds (mineral salts) in the soil E. Desertification is the degradation of once-fertile rangeland or forest into nonproductive desert caused partly by soil erosion, forest removal, overcultivation, and overgrazing IV. Soil conservation and regeneration A. Conservation tillage i. Conservation tillage is a method of cultivation in which residues from previous crops are left in the soil, partially covering it and helping to hold in place until the newly planted seeds are established ii. Conservation tillage reduces soil erosion, increases organic matter, and improves water-holding capacity iii. No-tillage leaves the soil undisturbed in the winter; it saves on fuel costs, machinery wear and tear, and labor time B. Crop rotation i. Crop rotation is the planting of a series of different crops in the same field over a period of years ii. It lessens insect damage and disease, helps retain essential nutrient minerals, decrease erosion, and helps maintains soil fertility C. Contour plowing, strip cropping, and terracing help control erosion of farmland with variable topography D. Preserving soil fertility can be accomplished through the use of both organic and commercial inorganic fertilizers E. Soil reclamation involves two steps, stabilizing the land to prevent further erosion (seeding and eventual ground cover)and restoring the soil to its former fertility i. Shelterbelts are one of the best ways to reduce the effects of wind on soil erosion ii. Agroforestry uses both forestry and agricultural techniques to improve degraded areas and offer economic benefits F. Soil conservation policies in the United States i. The Soil Conservation Act of 1935 authorized the formation of the Soil Conservation Service (now the NRCS); its mission is to work with U.S. citizens to conserve natural resources on private lands ii. The Food Security Act (Farm Bill) of 1985 contained provisions for two main soil conservation programs 1. Conservation compliance program 2. Conservation Reserve Program (CRP)

Chapter 14

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Digging a Hole

Time: Materials: Handouts:

10 minutes prep; 15 – 25 minutes in class Shovel(s), buckets or trays, picks, gloves, field bioscope None

Procedures:

Go to a place on or near campus where you have permission to dig.

Excavate, layer by layer, a 1 to 4 square foot section.

• Have students record what they find at each level.

• Keep a list of plants, animals, particle sizes, moisture. Look up close at some material to identify smaller particles and organisms.

• Have students discuss whether (and why or why not) this soil would be suitable for agriculture

Student Help your instructor dig a hole. Take notes: Instructions: • What types of organisms, organic and inorganic materials to you find as you dig down?

• Does this soil fit any of the profiles listed in chapter 15 of your book?

• Is the soil moist? Do you think it would retain moisture? Why or why not?

• Do you think this would make good agricultural soil? Why or why not?

• Do you think this soil is natural, or has it been changed by human activity? How and why?

Specific Suggestions: Objectives:

Avoid areas that might be contaminated with oils or hazardous materials…even though this could be very interesting • •

List the four components of soil Describe the various soil horizons

Chapter 14

Instructor Notes for In-Class Activity 2 Title:

Evaluating Soil Samples

Time: Materials:

15 or more minutes prep; 20 minutes in class Samples of soils from various locations, labeled with letters, in clear bags or jars Litmus paper (optional) List of sources of your soil (with spots for students to guess appropriate letters)

Handouts:

Procedures:

Preparation: 1. Gather samples of soil from various locations in clear bottles or bags.

2. Take notes on where you got the soil, including whether it has been modified by humans.

3. Label each sample with a letter.

4. Write out your notes on a sheet of paper in random order.

In class demonstration: 1. Divide class into groups of 3 – 4 2. Distribute soil samples to class. Ask them to look at the soil, and take notes about its physical characteristics (see book chapter 15).

3. Next, distribute your notes, and ask the students to match the soil samples to the notes.

4. As a class, discuss the students’ findings.

5. Present a sample of soil to the team with the most correct answers.

Student Working in groups of 3-4, evaluate the soil samples distributed by your Instructions: instructor. Take notes about its physical characteristics (see Chapter 15).

• Consider color, texture, particle size, moisture, odor and acidity.

• Describe any organic material • Is the sample homogeneous?

• Try to identify the major soil types: • spodosols, o alfisols, o mollisols, o aridosols, and o oxisols Next, compare your notes to the notes distributed by your instructor • Match the sample letters to the notes Explain why you made each match.

Specific Suggestions:

You may wish to include commercial potting soil, sand and clay.

Consider building up a collection over time as you travel.

As an option, have the students collect the soil samples

Chapter 14

Objectives:

• • •

List the four components of soil Describe soil texture Distinguish among major soil types

Chapter 14

Instructor Notes for In-Class Activity 3 Title:

Soil Amendment on Campus

Time: Materials: Handouts:

5 minutes prep; 30 + minutes in class Campus map None

Procedures:

Tour the campus as a class, looking at landscaping. Distribute campus maps to students.

Have students evaluate the following questions • What is the native soil like in your area?

• Would your native soils support the plants found around campus?

• What types of soil amendment products do you see?

• How much time does your campus grounds crew spend improving the soils?

• What happens to plant material that is trimmed or cleared from your campus? Is it composted locally, composted elsewhere, taken to landfill?

• What kinds of changes would be necessary to reduce or eliminate soil amendment on your campus?

Student See above Instructions: Specific Have someone from campus grounds crew tour with you, or come in and Suggestions: talk to your class before / after.

Consider getting permission to dig at one or more locations on campus Objectives:

• •

Define sustainable soil use Distinguish among major soil types

Chapter 14

Instructor Notes for In-Class Activity 4 Title:

A Worm’s Eye View

Time: Materials: Handouts:

0 minutes prep; 15 – 20 minutes in class None None

Procedures:

Have students select a location that they are familiar with, and recreate figure 15-5 (soil organisms) for soils in this location. Some possibilities are: deserts, lawns, flower gardens and parks.

Have them explain what animals and plants they expect to find in the soils, and what roles those organisms play.

Be sure that they include soil horizons.

Student See above.

Instructions: Specific Suggestions:

None

Objectives:

• •

Define soil and identify the factors involved in soil formation Describe the various soil horizons

Chapter 14

Instructor Notes for In-Class Activity 5 Title:

Growing Soil

Time: Materials: Handouts:

0 minutes prep; 15 – 20 minutes in class None None

Procedures:

Have the students collect soil samples from their yard. Bring them into class in baggies. Have a small pot for each of the students of a cup that they can put their soil in. Add some tomato seeds to each pot of soil and water. Each day have the students water equally and place all the pots of new tomato plants where there is sufficient sun. If the tomatoes grow see whose tomato taste the best, whose tomato is the best in color and size etc. See whose soil is the best to grow tomatoes. Does it make a difference with the soil?

Student See above.

Instructions: Specific Suggestions:

None

Objectives:

Briefly describe soil texture and soil acidity.

Chapter 14

Instructor Notes for In-Class Activity 6 Title:

Giving Back

Time: Materials: Handouts:

30 minutes prep time, up to 4 hours class time None None

Procedures:

Call your city’s planning or environmental department and find a spot of land that is at risk for soil erosion or needs to be cleaned up. Have the class raise money or get community support to plant trees on this spot of land and clean it up. This would be a great Saturday activity for the students and community. Some tree nurseries may donate trees they can’t sell to help your project. Get the news involved and see if your class can make a contribution to beautifying a spot of land.

Student See above.

Instructions: Specific Suggestions:

None

Objectives:

Explain the impacts of soil erosion and mineral depletion on plant growth and on other resources such as water.

Chapter 14

Answers to Critical Thinking and Review End of Chapter Questions: 1. Why do we consider soil to be a system?

Ans: Soil has many components, the soil system is composed of inorganic nutrient minerals, organic materials, soil air, and soil water. Human activities often cause or exacerbate soil problems, including erosion, mineral depletion of the soil, soil salinization, and desertification, all of which occur worldwide. Such activities do not promote sustainable soil use.

2. Explain the roles of weathering, organisms, climate, and topography in soil formation.

Ans: Soil is formed from parent material (rock) that is slowly broken down, or fragmented, into smaller and smaller particles by biological, chemical, and physical weathering processes in nature. The weathering of parent material beneath already-formed soil continues to add new soil.

Organisms and climate both play essential roles in weathering, sometimes working together.

When plant roots and other soil organisms respire, they produce carbon dioxide, CO2, which diffuses into the soil and reacts with soil water to form carbonic acid, H2CO3. Organisms such as lichens produce other kinds of acids. These acids etch tiny cracks in the rock; water then seeps into these cracks. If the parent material is located in a temperate climate, the alternate freezing and thawing of the water during the winter causes the cracks to enlarge, breaking off small pieces of rock. Small plants then become established and send their roots into the larger cracks, fracturing the rock further. Topography, a region's surface features, such as the presence or absence of mountains and valleys, is also involved in soil formation. Steep slopes often have little or no soil on them because soil and rock are continually transported down the slopes by gravity; runoff from precipitation tends to amplify erosion on steep slopes. Moderate slopes and valleys, on the other hand, may encourage the formation of deep soils.

3. What are the four distinct parts of the soil system?

Ans: The soil system is composed of four distinct parts: mineral particles, organic matter, water, and air.

4. Which soil horizons are most prone to erosion? How might your answer be significant to farmers?

Ans: A horizons are most prone to erosion. Although estimates vary widely depending on what assumptions are made, soil erosion results in an annual loss of as much as 75 billion metric tons (83 billion tons) of topsoil around the world. In India and China, soil experts estimate that erosion causes an annual loss of as much as 6.6 billion metric tons and 5.5 billion metric tons of soil, respectively. These two countries have 13% of the world's total land area from which they must feed 2.43 billion people—more than 37% of the world's human population. With the loss of top soil agricultural lands become less fertile which may lead to famine. Farmers need to minimize erosion to maintain soil fertility which is essential for crop production.

5. How do organisms contribute to nutrient cycling in the soil system?

Chapter 14 Ans: Millions of microorganisms, including bacteria, fungi, algae, microscopic worms, and protozoa inhabit soil. Many other organisms including insects, earthworms, moles, snakes, and groundhogs also inhabit the soil ecosystem.

Soil organisms provide essential ecosystem services such as maintaining soil fertility by decaying and cycling organic material, preventing soil erosion, breaking down toxic pollutants, cleansing water, and affecting the composition of the atmosphere.

6. How does the presence of various-sized particles (sand, silt, and clay) affect soil characteristics?

Ans: Soil texture refers to the relative proportions of different-sized inorganic mineral particles of sand, silt, and clay. The size assignments for sand, silt, and clay give soil scientists a way to classify soil texture. The largest soil particles (0.05 to 2 mm in diameter) are sand, medium-sized particles (0.002 to 0.05 mm in diameter) are silt, and small particles (less than 0.002 mm in diameter) are clay. A soil's texture affects many of a soil's properties, which in turn influence plant growth. Clay is particularly important in determining many soil characteristics because clay particles have the greatest surface area of all soil particles.

7. Give an example of how plants affect soil pH. Give an example of how soil pH affects plants.

Ans: Soil pH affects plants partly because the solubility of certain nutrient minerals varies with differences in pH. Plants absorb soluble mineral elements, but cannot absorb insoluble forms.

Soil pH affects plants and, in turn, is influenced by plants and other soil organisms. Litter composed of the needles of conifers contains acids that leach into the soil, lowering its pH. The decomposition of humus and the cellular respiration by soil organisms also decrease the pH of soil.

8. Which two of these soil orders are best suited for agriculture: spodosol, alfisoil, mollisol, aridosol, and oxisol? Why? Ans: Most of the world's grain crops are grown on mollisols. Some aridisols provide rangeland for grazing animals, and crops can be grown on aridisols if water is supplied by irrigation.

9. The pie chart shows an overview of the world’s total land area with respect to its suitability for agriculture. How could soil that is too dry for agriculture be converted to cropland? How could soil that is too wet for agriculture be converted to cropland? Explain why each of the remaining three categories in the pie chart cannot be converted to agricultural land.

INSERT PIE CHART FROM THIS QUESTION PAGE 305 Ans: Answers will vary.

10. How does sustainable soil use protect the agricultural soil system?

Ans: Human activities often cause or exacerbate soil problems, including erosion, mineral depletion of the soil, soil salinization, and desertification, all of which occur worldwide. Such

Chapter 14 activities do not promote sustainable soil use. Soil used in a sustainable way renews itself by natural processes year after year. Sustainable soil use means the system has no reduction in the amount or fertility of soil, it therefore remains productive for future generations. Conservation tillage, crop rotation, contour plowing, strip cropping, terracing, shelterbelts, and agroforestry help to protect agriculture soil.

11. Describe two ways in which nutrient minerals are lost from the soil.

Ans: Nutrient minerals can be lost from the soil by leaching and by plant removal. Any nutrient minerals released as dead organisms decay in the soil and are promptly reabsorbed by plant roots and their mutualistic fungi. If this did not occur, the heavy rainfall would quickly leach the nutrient minerals away. Nutrient reabsorption by vegetation is so effective that tropical rainforest soils support luxuriant plant growth despite the relative infertility of the soil, as long as the forest remains intact.

When a forest is cleared, whether to sell the wood or to make way for crops or rangeland, its efficient nutrient cycling is disrupted. Removal of the vegetation that so effectively stores the forest's nutrient minerals allows them to leach out of the system.

12. Where does eroded soil go after it is transported by water, wind, or ice?

Ans: Water, wind, ice, and other agents promote soil erosion. Water and wind are particularly effective in moving soil from one place to another. Rainfall loosens soil particles, which are then transported away by moving water. Wind loosens soil and blows it away, particularly if the soil is barren and dry. Sediment that gets into streams, rivers, and lakes affects water quality and fish habitats. When forests are removed within the watershed of a hydroelectric power facility, accelerated soil erosion causes the reservoir behind the dam to fill with sediment much faster than usual. This process results in a reduction of electricity production at that facility.

13. This graph relates spring wheat production (measured in kg of wheat per hectare of cultivated land) to soil erosion (measured in cm of topsoil lost) in the northern Great Plains. How does soil erosion affect wheat yields. SEE GRAPH ON PAGE 305 Ans: As erosion increases soil fertility and wheat yield decrease dramatically.

14. How is human overpopulation related to world soil problems?

Ans: Asia and Africa have the largest land areas with extensive soil damage, and in both places rapid population growth compounds this problem. Consider the Sahel, a broad band of semiarid land that stretches across Africa just south of the Sahara Desert. The Sahel normally experiences periodic droughts, but for the past 30 years there has been a sustained rainfall deficit—that is, substantially less precipitation than normal. During droughts, the soil cannot support as many crops or grazing animals. Despite the drought, the Sahelians must use their land to grow crops and animals for food or they will starve. The soil is so overexploited under these circumstances that it supports fewer and fewer people; the day is approaching when the Sahel could become unproductive desert.

Chapter 14

15. The American Dust Bowl is sometimes portrayed as a “natural” disaster brought on by drought and high winds. Present a case for the view that this disaster was not caused by nature as much as by humans.

Ans: The effects of wind on soil erosion were vividly experienced over a wide region of the central United States during the 1930s. Throughout the late 19th and early 20th centuries, much of the native grasses were removed to plant wheat. Then, between 1930 and 1937, the semiarid lands stretching from Oklahoma and Texas into Canada received 65% less annual precipitation than was normal. The rugged prairie grasses that were replaced by crops could have survived these conditions, but not the wheat. The prolonged drought caused crop failures, which left fields barren and particularly vulnerable to wind erosion.

16. Distinguish among conservation tillage, crop rotation, contour plowing, strip cropping, terracing, shelterbelts, and agroforestry as methods of sustainable soil use.

Ans: Conservation tillage is a method of cultivation in which residues from previous crops are left in the soil, partially covering it and helping to hold it in place until the newly planted seeds are established. Crop rotation is the planting of a series of different crops in the same field over a period of years. Contour plowing is plowing that matches the natural contour of the land. Strip cropping, a special type of contour plowing, produces alternating strips of different crops along natural contours. Terracing produces level areas on steep slopes and thereby reduces soil erosion.

A shelterbelt is a row of trees planted as a windbreak to reduce soil erosion of agricultural land.

Agroforestry is the use of both forestry and agricultural techniques to improve degraded areas and offer economic benefits.

17. President Franklin D. Roosevelt once sent a letter to the state governors in which he said, “A nation that destroys its soils, destroys itself.” Would he have supported the Conservation Reserve Program? Explain your answer.

Ans: Healthy soil provides us with many services including, fertile areas to grow crops, purification of ground water, shade trees, and wildlife habitat. If soils are managed poorly they can be lost or become infertile. Degraded soil leads to crop failure, human suffering and political unrest. The Conservation Reserve Program is a voluntary program that pays farmers to stop producing crops on highly erodible farmland. It requires planting native grasses or trees and then retiring the land from further use for 10 to 15 years.

18. Does conversion of undisturbed land to farmland impact the global carbon cycle and climate change? Explain your answer.

Ans: Conversion of land from undisturbed forest or grassland to farmland, is known to increase the release of CO2 from soil organic compounds, which are decomposed at a faster rate in agricultural soils than in undisturbed soils.

Answers to Review Questions

Chapter 14

The Soil System 1. How do weathering processes affect soil formation?

Soil is formed from parent material, rock that is slowly broken down, or fragmented, into smaller and smaller particles by biological, chemical, and physical weathering processes in nature. Soil organisms play an important role in biological weathering processes, carbon dioxide plays an important role in chemical weathering processes, and climate plays an important role in physical weathering processes. Moreover, the weathering of parent material beneath already-formed soil continues to add new soil, and replaces nutrient minerals, to the soil ecosystem.

2. What are the four components of soil, and how is each important?

The soil system is composed of four distinct parts: inorganic nutrient mineral particles make up about 45% of typical soil; organic matter accounts for about 5%; and air and water each compose about 25%. The inorganic portion, which comes from weathered parent material, provides anchorage and essential nutrient minerals for plants as well as pore space for water and air. The organic material decomposes, releasing essential nutrient mineral ions into the soil, where they are absorbed by plant roots. Lastly, the soil air and soil water produce a moist, but aerated, soil that sustain plants and other soildwelling organisms.

3. What are soil horizons? Distinguish between the O-horizon and A-horizon.

Soil horizons are the horizontal layers into which many soils are organized, from the surface to the underlying parent material. The uppermost layer of soil, the O-horizon, contains plant litter that gradually decays. It is rich in organic material and is often the dominant layer in certain organically rich soils. Just beneath the O-horizon is the topsoil, or A-horizon, which is dark and rich in accumulated organic matter and humus.

The A-horizon is somewhat nutrient-poor owing to the gradual loss of many nutrient minerals to deeper layers by leaching.

4. Name two ecosystem services that soil organisms perform.

Forming soil and cycling nutrient minerals are two ecosystem services provided by soil organisms. Others ecosystem services provided by soil organisms include maintaining soil fertility by decaying and cycling organic material, preventing soil erosion, breaking down toxic pollutants, cleansing water, and affecting the composition of the atmosphere.

Soil Properties and Major Soil Types 1. What is soil texture?

Chapter 14 Texture is a parameter that characterizes soils. Soil texture refers to the relative proportions of different sized inorganic mineral particles of sand, silt, and clay in the soil.

It does not refer to the organic material in the soil, only the inorganic minerals. These various mineral particles range in size from 0.002 mm to 2 mm in diameter.

2. What is the optimum pH of most soils? What happens if the soil pH falls out of this range?

Most soils range from a pH of 4 (acidic) to 8 (slightly alkaline); although, the optimum soil pH for most plant growth is 6.0 to 7.0 because most of the nutrient minerals needed by plants are available in that pH range. If the soil pH falls out of this range it can affect the availability of soil nutrients to the plant. For example, at a low pH the aluminum and manganese in soil water are more soluble, and the roots sometimes absorb them in toxic concentrations. Conversely, certain mineral salts essential for plant growth (i.e., calcium phosphate) become less soluble and less available to plants at a high pH. Soil pH also greatly affects the leaching of nutrient minerals (i.e., potassium).

3. Which of the five soil orders (spodosols, alfisols, mollisols, aridosols, and oxisols) is associated with deserts? With tropical forests? With semiarid grasslands?

Aridisols are found in arid regions such as deserts. Oxisols are low in nutrient minerals and exist in tropical and subtropical areas with ample precipitation. Fertile mollisols are found primarily in temperate, semiarid grasslands.

Environmental Problems Related to Soil 1. What is sustainable soil use?

Sustainable soil use is the wise use of soil resources, without a reduction in soil fertility, so that the soil remains productive for future generations. Soil used in a sustainable way renews itself by natural processes year after year.

2. How would you distinguish between soil erosion and nutrient mineral depletion?

Soil erosion is the wearing away or removal of soil from the land; it is brought about by water, wind, ice, and other agents. Erosion causes an overall loss of soil fertility, and because it reduces the amount of soil in an area, it also tends to limit the growth of plants.

Overall, soil erosion is a natural process accelerated by human activities (i.e., poor soil management practices and the removal of natural plant communities).

In natural ecosystems, essential nutrient minerals cycle from the soil to the organisms which absorb them. Because agricultural systems disrupt the natural pattern of nutrient cycling in soil ecosystems, nutrient mineral depletion occurs in all soils that are farmed and inevitably leads to an overall decrease in soil fertility. A combination of factors can cause nutrient mineral depletion, including unsound farming methods, extensive soil erosion, and desertification.

Chapter 14

3. What was the American Dust Bowl?

The American Dust Bowl occurred in the 1930s, and damaged more than 30 million hectares of land in the Great Plains. It resulted from a combination of the widespread removal of native grasses to plant wheat, and several years of less annual precipitation than normal. The prolonged drought caused crop failures. Subsequently, this allowed for winds to sweep across the barren, exposed soil, and cause massive dust storms. The American Dust Bowl is an example of accelerated wind erosion caused by use of marginal land for agriculture.

Soil Conservation and Regeneration 1. What is crop rotation? Strip cropping?

Crop rotation is the planting of a series of different crops in the same field over a period of years, thereby maintaining soil fertility. Strip cropping is a type of contour plowing in which different crops are laid out in alternating, narrow strips along natural contours, as on a hillside.

2. How can degraded soils be reclaimed? What is the Conservation Reserve Program?

Degraded soils can generally be reclaimed by following two steps: (1) stabilizing the land to prevent further erosion and (2) restoring the soil to its former fertility. It is a slow process, and use of the land must be restricted during the soil’s recovery.

The Conservation Reserve Program is a voluntary program that pays farmers to stop producing crops on highly erodible farmland.

Chapter 15 Mineral Resources Lecture Outline: I. Introduction to Minerals A. Minerals are elements or compounds of elements that occur naturally in Earth’s crust and have precise chemical compositions i. Sulfides are mineral compounds in which certain elements are combined chemically with sulfur ii. Oxides are mineral compounds in which elements are combined chemically with oxygen iii. Rocks are naturally formed aggregates, or mixtures, of minerals and have varied chemical compositions 1. An ore is a rock that contains a large enough concentration of a particular mineral to be profitably mined and extracted 2. Ores are classified as either high-grade or low-grade iv. Minerals are metallic or nonmetallic 1. Metals are minerals such as iron, aluminum, and copper, which are malleable, lustrous, and good conductors of heat and electricity 2. Nonmetallic minerals, such as sand, stone, salt and phosphates, lack these characteristics B. Mineral distribution and formation i. Mineral deposits in Earth’s crust are unevenly distributed ii. Formation of mineral deposits 1. Concentrations of minerals within Earth’s crust are the result of several natural processes a. Magmatic concentration produces iron, copper, nickel, and chromium b. Hydrothermal processes produce gold, silver, copper, lead, and zinc c. Sedimentation produces iron, manganese, phosphorus, sulfur, copper d. Evaporation produces salt, borax, potassium, salts, gypsum C. How minerals are found, extracted, and processed i. Discovering mineral deposits 1. Aerial or satellite photography sometimes discloses geologic formations associated with certain types of mineral deposits 2. Aircraft, satellite instruments, 3-D maps, and seismographs are also used to provide clues about mineral deposits ii. Extracting minerals 1. Surface mining extracts minerals near the surface, while subsurface mining extracts minerals too deep to be removed by surface mining a. In surface mining, overburden and vegetation must first be removed before scooping minerals out

Chapter 15 i.

Open-pit and strip mining are two kinds of surface mining ii. Quarries and spoil banks are the respective result of each type of mining b. Subsurface mining may be done with a shaft mine or a slope mine i.

Subsurface mining disturbs the land less than surface mining ii. Subsurface mining is more expensive and hazardous for miners iii. Processing minerals 1. Processing minerals often involves smelting 2. Molten iron and slag result from the process of smelting II. Environmental Impacts of Minerals A. Mining and the environment i. Mining disturbs large areas of land, destroys existing vegetation, amplifies erosion, and leads to air and water pollution ii. Mining affects water quality 1. In the U.S., mining has contributed to the contamination of at least 11,800 miles of streams and rivers 2. Acid mine drainage is washed into soil and water by precipitation runoff iii. Cost-benefit analysis of mine development 1. Environmental economists suggest that before a decision is made to develop a mine, analysis should be performed that includes the benefits of the mine in dollar terms versus the benefits in dollar terms of preserving the land intact for wildlife habitat, indigenous people, watershed protection, and recreation 2. It should include the cost of damage to the environment caused by extracting and processing mineral resources B. Environmental impacts of refining minerals i. Approximately 80% or more of mined ore consists of impurities that become wastes after processing 1. Tailings are usually left in giant piles on the ground or in ponds near the processing plants 2. Tailings contain toxic materials and contaminate air, soil and water ii. Other impurities contained in many mineral ores are sulfur, lead, cadmium, arsenic, and zinc iii. One of the most significant environmental impacts in mineral production is the large amount of energy required to mine and refine minerals C. Restoration of mining lands i. The goals of reclamation include preventing further degradation and erosion of the land, eliminating or neutralizing local sources of toxic pollutants, and making the land productive for purposes other than mining ii. Lands degraded by mining are often called derelict lands, their restoration is mainly limited by lack of funding

Chapter 15 iii. The Surface Mining Control and Reclamation Act of 1977 requires reclamation of areas that were surface mined for coal iv. Creative approaches to cleaning up mining areas 1. A series of wetlands constructed in the affected drainage basin is an effective way to help clean up former mining lands 2. An inexpensive approach uses cow manure to increase the pH of the mine drainage water, thus increasing bacterial growth and precipitating toxic materials out of the basic water 3. Plants are used to remove heavy metals from former mining lands through a process called phytoremediation III. Minerals: an International Perspective A. U.S. and world use i. Humans have consumed more minerals since World War II than were consumed in the previous 5000 years ii. Industrialization increases the demand for minerals, developing countries that at one time met their mineral needs with domestic supplies become increasingly reliant on foreign supplies as development occurs B. Distribution versus consumption i. Will we run out of important minerals?

1. Mineral reserves are currently profitable to extract, whereas mineral resources are potential resources that may be profitable to extract in the future 2. The combination of mineral’s reserves and resources is its total resources or world reserve base a. Estimates of the world reserve base fluctuate with economic, technological, and political changes b. It is extremely difficult to forecast future mineral supplies IV. Increasing the Supply of Minerals A. Locating and mining new deposits i. Many known mineral reserves have not yet been exploited ii. Geologists consider it likely that deep deposits buried 10km or more in the Earth’s crust will someday be discovered and exploited B. Minerals in Antarctica i. The Antarctic Treaty (1961) limits activity in Antarctica to peaceful uses such as scientific studies; nobody owns Antarctica ii. The Environmental Protection Protocol to the Antarctic Treaty (Madrid Protocol of 1990) includes a moratorium on mineral exploration and development for a minimum of 50 years iii. Polar regions such as Antarctica are extremely vulnerable to human activities C. Minerals from the ocean i. Minerals can be extracted from seawater ii. The sea floor may be mined where minerals have accumulated 1. Manganese nodules are widespread on the ocean floor 2. It is not clear which country has the legal right to minerals in international waters

Chapter 15 iii. The U.N. Convention of the Law of the Sea (UNCLOS – 1994) protects the resources of the ocean D. Advanced mining and processing technologies i. As minerals grow scarcer, economic and political pressure to exploit lowgrade ores will increase ii. Despite advanced technology, limiting factors in obtaining minerals from lowgrade ores may be water and environmental costs iii. Biomining 1. In some cases, microorganisms are used to extract minerals from lowgrade ores 2. This process has been used to mine copper, gold and phosphates V. Using Substitution and Conservation to Expand Mineral Supplies A. Finding mineral substitutes i. Economics partly drives the search for substitutes; one effective way to cut production costs is to substitute an inexpensive or abundant material for an expensive or scarce one 1. Plastics, ceramic composites, and high-strength glass fibers are examples of substitutes 2. Use of tin, lead, and steel have been drastically decreased in the past 35 years due to plastic substitutes ii. Certain minerals have no known substitutes B. Mineral conservation i. Reuse 1. Reuse extends mineral resources, reduces mineral consumption and reduces pollution 2. Reuse helps save tax money by reducing litter and solid waste 3. The benefits of reuse are greater than those of recycling ii. Recycling 1. Recycling converts mineral resources into new products; it saves unspoiled land from the disruption of mining, reduces the amount of solid waste that must be disposed, and decreases energy consumption and pollution 2. Significant amounts of gold, lead, nickel, steel, copper, zinc, and aluminum are recycled 3. About 44% of the aluminum cans in the U.S. are currently recycled iii. Changing our mineral requirements 1. We can reduce mineral consumption by becoming a low-waste society 2. We consume fewer resources if products are durable and repairable 3. Sustainable manufacturing is a system based on industrial waste minimization; it requires that companies provide information about their waste products to other industries iv. Dematerialization 1. The decrease of the weight of products over time is known as dematerialization 2. It reduces the quantity of waste during both production and consumption

Chapter 15 3. Dematerialization can lead to the increase of consumption of both materials and minerals due to increased replacement of such items

Chapter 15

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Copper Through Time

Time: Materials: Handouts:

5 minutes prep; one class period Internet access None

Procedures:

Divide class into four groups (multiples of four if you have a large class).

Have one group explore each of the following, and give a two to three minute report to the class at the end of the day (or a longer report for the start of the following session) Group One will investigate the uses and sources of copper from earliest recorded history to 1800. They should note the technologies that allowed copper extraction and production, and the uses of copper for technologies, weapons and adornments Group Two should do the same for copper from 1800 to the 1950’s.

Group Three should look at how and where copper is extracted and produced today Group Four should explore how copper is used for technological applications from the 1960’s to today After the reports, open a discussion, exploring the following: • How has the use of copper changed over time?

• What materials do we use now for uses that copper filled in the past?

• Are these replacement minerals more or less environmentally friendly than copper?

• Discuss telecommunications specifically…how have cell phones impacted demand for copper?

Student Research the time periods and subjects assigned to your group. Create a Instructions: two to three minute report, and choose a member of your group to report back to the class.

Specific Suggestions: Objectives:

None • • •

Describe how minerals are extracted and processed Describe how a metallic mineral has been used through history Explain dematerialization

Chapter 15

Instructor Notes for In-Class Activity 2 Title:

The King and His Three Daughters

Time: Materials: Handouts:

25 minutes prep; 10 minutes in class None None

Procedures:

Tell your students the following story: Once upon a time, there was a King who had three daughters. As he grew older, he could not decide which of these daughters would be the best ruler of the kingdom when he was gone, so he decided to leave the kingdom to the daughter who loved him best. So he called his three daughters to him, and asked each of them in turn “Daughter, how much do you love me?”

The eldest daughter did not hesitate to tell him “Father, I love you more than gold and silver, more than all of the coins in the realm!” The King was most impressed by this, and had the daughter sit down by his side.

The second daughter smiled brightly and said “Father, I love you more than diamonds, rubies, and more than all of the emeralds in your crown!”

The King, who adored emeralds, was pleased to hear this as well, and had the second daughter sit at his side.

The youngest daughter thought carefully before saying “Father, I love you more than salt.” The King was incensed. Salt! Did she think so little of him that she only loved him more than salt!

“You, daughter, are banished from the kingdom!” he told her, and laughed that she could take with her all the salt that she wished.

An old crone who had known the daughters since birth told the youngest in secret “I’ll come with you my dear, and help you to carry your salt.”

No one, not even the Princesses knew that the old crone knew powerful magic. She captured all of the salt in the kingdom in a small box that she wore around her neck.

Over the next few weeks, the people and animals of the kingdom began to grow ill from lack of salt. At last, the King was heard to cry, “I would give all of my money, all of my jewels, if only I could have some salt!”

As soon as he had said these words, the old crone walked into the room, saying, “My lord, I can make that exchange. I ask only one other thing: that my mistress should be allowed to return here to rule the kingdom.”

The King, faced with a life of misery for himself and his subjects (and not knowing who this woman’s mistress was) agreed.

Chapter 15 The old woman opened the box, and salt was again available throughout the kingdom. To the King’s great joy, the old crone returned with her mistress—the Princess—who ruled wisely and well for many years to come.

Student Discuss, what does this story tell us about minerals?

Instructions: Specific Suggestions:

Practice several times.

Make the story your own—this is a sketch, not to be read verbatim!

For best effect, tell it as a storyteller, and don’t warn your students that it is coming.

Objectives:

Contrast the relative importance of exotic and mundane minerals.

Chapter 15

Instructor Notes for In-Class Activity 3 Title:

Three Sources of Stuff

Time: Materials: Handouts:

10 minutes prep; 20 – 30 minutes in class Anything and everything Stuff, Source, Alternative(see below)

Procedures:

Divide the students into groups of 3 – 4. Have them • Make a list of 15 things that are found in your classroom.

• Identify whether each of these is made from minerals, petroleum products, or agricultural products (note that many things will have more than one of these) • For each of these, identify: o Whether the item is durable or disposable o The extent to which each item can be reused or recycled o Potential substitutes made from one of the other categories o The environmental impacts of producing, using and disposing of the product.

Student Working in groups of 3 – 4 fill in the worksheet provide by your Instructions: instructor.

Specific Suggestions:

NA

Objectives:

• •

Describe the origins and nature of commercial products Explain alternatives to and environmental impacts of durable and disposable products

Chapter 15 In-Class Activity 3: Handout Complete the following for 20 items found in your classroom (can include ANY item, permanent or temporary).

For “origins” consider whether the item’s origin is mineral, petroleum, agriculture, or a combination.

For “environmental impacts,” consider creation, use and disposal.

Item

Origin

Durable / Disposable?

Reusable / recyclable?

Alternative Product

Environmental Impacts

Chapter 15

Instructor Notes for In-Class Activity 4 Title:

A ghost town

Time: Materials: Handouts:

0 minutes prep; 30 - 40 minutes in class None None

Procedures:

As a class have them research a mining town that is now vacant.

Check and research the land around this town, what type of land is it for example desert, grassland, mountains, forest etc.

Research the history around the town, what minerals were mined that caused the town to grow. Why did the town die? Are there still minerals in the area?

Student Instructions:

Have the students brainstorm ideas on how this ghost mining town could be revitalized and what impact it would have on the environment. .

See above.

Specific Suggestions:

None

Objectives:

Explain how mining lands can be restored.

Chapter 15

Instructor Notes for In-Class Activity 5 Title:

What’s it worth?

Time: Materials: Handouts:

10 minutes prep; 15 – 20 minutes in class Plastic bottle, glass bottle, paper bag, Al can, cloth towel, None

Procedures:

Divide the class into 5 teams. Have the leader of the team come up and draw into the bag an item above. (plastic bottle, glass bottle, paper bag, Al can, cloth towel) The leader takes his /her item back to the team and they are to research and brainstorm everything that went into making that item. They can use the internet, talk to people etc. Then they need to research how many different ways they can recycle that item.

Have them also discuss how they can reduce, reuse and recycle the item they picked.

Present to the class.

Student See above.

Instructions: Specific Suggestions:

None

Objectives:

Summarize the conservation of minerals by reuse, recycle and changing our mineral requirement.

Chapter 15

Answers to Critical Thinking and Review End of Chapter Questions: 1. What is the difference between rocks and minerals? Between metals and nonmetallic minerals?

Ans: Earth's minerals are elements or (usually) compounds of elements and have precise chemical compositions. Rocks are naturally formed aggregates, or mixtures, of minerals and have varied chemical compositions. Minerals are metallic or nonmetallic. Metals are minerals such as iron, aluminum, and copper, which are malleable, lustrous, and good conductors of heat and electricity. Nonmetallic minerals, such as sand, stone, salt, and phosphates lack these characteristics.

2. Distinguish between surface and subsurface mining, between open-pit and strip mines, between shaft and slope mines.

Ans: Surface mining is the extraction of mineral and energy resources near Earth’s surface by first removing the soil, subsoil, and over-lying rock strata. Subsurface mining is the extraction of mineral and energy resources from deep underground deposits. There are two kinds of surface mining, open-pit surface mining and strip mining. Iron, copper, stone, and gravel are usually extracted by open-pit surface mining, in which a giant hole is dug. In strip mining, a trench is dug to extract the minerals. Subsurface mining, which is underground, may be done with a shaft mine or a slope mine. A shaft mine is a direct vertical shaft to the vein of ore. The ore is broken up underground and then hoisted through the shaft to the surface in buckets. A slope mine has a slanting passage that makes it possible to haul the broken ore out of the mine in cars rather than hoisting it up in buckets

3. Distinguish among the following ways in which mineral deposits may form: magmatic concentrations, hydrothermal processes, sedimentation, and evaporation.

Ans: As magma (molten rock) cools and solidifies deep in Earth's crust, it often separates into layers, with the heavier iron- and magnesium-containing rock settling on the bottom and the lighter silicates (rocks containing silicon) rising to the top. Varying concentrations of minerals

Chapter 15 are often found in the different rock layers. This layering, called magmatic concentration, is responsible for some deposits of iron, copper, nickel, chromium, and other metals.

Hydrothermal processes involve water that was heated deep in Earth's crust. This water seeps through cracks and fissures and dissolves certain minerals in the rocks. The minerals are then carried along in the hot water solution.

Weathered particles are transported by water and deposited as sediment on riverbanks, deltas, and the sea floor in a process called sedimentation. During their transport, certain minerals in the weathered particles dissolve in the water. They later settle out of the solution. When the warm water of a river meets the cold water of the ocean, settling occurs because less material dissolves in cold water than in warm water.

Significant amounts of dissolved materials accumulate in inland lakes and in seas that have no outlet or only a small outlet to the ocean. If these bodies of water dry up by evaporation, a large amount of salt is left behind. Over time, it may be covered with sediment and incorporated into rock layers. Evaporation has formed significant deposits of common table salt, borax, potassium salts, and gypsum.

4. What is overburden? A Spoil bank? Smelting? Tailings?

Ans: Overburden is soil and rock overlying a useful mineral deposit. A spoil bank is a hill of loose rock created when the overburden from a new trench is put into the already excavated trench during strip mining. Smelting is the process in which ore is melted at high temperatures to separate impurities from the molten metal. On average, approximately 80% or more of mined ore consists of impurities that become wastes after processing. These wastes, called tailings, are usually left in giant piles on the ground or in ponds near the processing plants

5. Explain why it is more environmentally damaging to obtain minerals from low-grade ores than to extract them from high-grade ores.

Ans: High-grade ores contain relatively large amounts of particular minerals, whereas low-grade ores contain lesser amounts. More low-grade ore must be extracted to obtain the same amount of minerals extracted from high-grade sources.

Chapter 15 6. Historically, the cost of environmental damage arising from mining and processing minerals was not included in the price of consumer products. Do you think it should be? Why or why not?

Ans: Answers will vary.

7. How did Copper Basin, Tennessee become an environmental disaster?

Ans: During the middle of the 19th century, copper ore was discovered near Ducktown in southeastern Tennessee. Copper mining companies extracted the ore from the ground and dug vast pits to serve as open-air smelters. They cut down the surrounding trees and burned them in the smelters to produce the high temperatures needed for the separation of copper metal from other contaminants in the ore. The ore contained great quantities of sulfur, which reacted with oxygen in the air to form sulfur dioxide. As sulfur dioxide from the open-air smelters billowed into the atmosphere, it reacted with water, forming sulfuric acid that fell as acid precipitation. As a result of deforestation and acid precipitation, ecological ruin of the area occurred in a few short years. Acid precipitation quickly killed any plants attempting a comeback after removal of the forests. Because plants no longer covered the soil and held it in place, soil erosion cut massive gullies in the gently rolling hills. Of course, the forest animals disappeared with the plants, which had provided their shelter and food. The damage did not stop here. Soil eroding from the Copper Basin, along with acid precipitation, ended up in the Ocoee River, killing its entire aquatic community.

8. Compare mineral consumption in the United States, China, and a developing country as Nigeria. Which of these countries has experienced the most rapid increase in mineral consumption in recent years? Why?

Ans: The United States consumes a significant portion of the world’s minerals. Consumption of mineral’s has remained steady in the U.S. China’s has seen a significant increase in mineral consumption over the past years due to a dramatic increase in industrialization. Nigeria’s consumption of minerals is minimal due to its lack of industrialization. China’s rapid industrialization has led to a significant increase in its demand and consumption of minerals.

Chapter 15 9. Why do we have to distinguish between mineral resources and mineral reserves when making projections about how long a specific mineral will be available? Why it is difficult to obtain an accurate appraisal of total resources for a particular mineral?

Ans: Mineral reserves are currently profitable to extract, whereas mineral resources are potential resources that may be profitable to extract in the future.

Geologists employ a variety of instruments and measurements to help locate valuable mineral deposits. Aerial or satellite photography, aircraft and satellite data of magnetic fields and gravity, and seismographs, are all methods employed to locate potential mineral sites. Once these sites are identified, mining companies drill or tunnel for mineral samples and analyze their composition. Because minerals are difficult to locate it is difficult to get an estimate of total mineral resources.

10. What are manganese nodules? Why have these known deposits not been mines?

Ans: Manganese nodules are small rocks the size of potatoes that contain manganese and other minerals, such as copper, cobalt, and nickel. They are widespread on the ocean floor, particularly in the Pacific. The current market value would not cover the expense of obtaining manganese nodules from the ocean floor using existing technology.

11. Have mineral deposits been mined in Antarctica? Why or why not?

Ans: To date no substantial mineral deposits have been found in Antarctica.

12. Sketch mineral flow in a traditional industrialized society. Make sure you include mines, mills, factories, homes, and businesses. Now sketch mineral flow in a low-waste industrialized society. Which diagram is more complex, and why?

Ans: Answers will vary.

Chapter 15 13. Some people in industry argue that the planned obsolescence of products, which means they must be replaced often, creates jobs. Others think that the production of smaller quantities of durable, repairable products would generate jobs and stimulate the economy. Explain each viewpoint.

Ans: Answers will vary.

14. How does the industrial ecosystem at Kalundborg resemble a natural ecosystem? Would this approach produce more, or fewer, greenhouse gases than if the same energy and products were produced using traditional industrial practices? Explain.

Ans: In this industrial ecosystem, the wastes produced by one company are sold to another company as raw materials for their processes, in a manner analogous to nutrient cycling in nature. As a result of this cycling, the need for 3500 oil-burning home heating systems was eliminated. The power plant now saves tons of coal each year by burning less expensive natural gas. Excess sulfur is removed from oil and sold to a company that uses it to manufacture sulfuric acid. To meet environmental regulations, the power plant installed pollution-control equipment to remove sulfur from its coal smoke. This sulfur, in the form of calcium sulfate, is sold to the wallboard plant and used as a substitute for gypsum. The fly ash produced by the power plant goes to the cement manufacturer for use in road building. Local farmers use the sludge from the fish farm as a fertilizer for their fields. The fermentation vats at the pharmaceutical plant also generate a high-nutrient sludge used by local farmers. This approach most likely would produce fewer greenhouse gases.

15. Examine the graph, which shows that world use of electricity for mining and refining virgin aluminum has increased since the 1950s. Given that the production of aluminum has become more energy efficient in recent years, how do you account for the current global increase in electricity used in aluminum production?

See graph for Question 15 on Page 324

Ans: As countries industrialize there demand for minerals increases. Therefore, even though aluminum production has become more efficient, overall demand as gone up.

Answers to Review Questions

Chapter 15

Introduction to Minerals 1. What is the difference between high-grade and low-grade ores?

An ore is rock that contains a large enough concentration of a particular mineral to be profitably mined and extracted. High-grade ores contain relatively large amounts of particular minerals, whereas low-grade ores contain lesser amounts.

2. Which type of mining – surface mining or subsurface mining – is more harmful to the environment? Which type is more expensive to do?

Surface mining is more harmful to the environment. Subsurface mining is more expensive to do.

3. How does magmatic concentration form mineral deposits?

Magmatic concentration is the formation of mineral deposits as liquid magma separates into layers, cools, and solidifies. During magmatic concentration the heavier ironcontaining rock settles on the bottom and the lighter silicates rise to the top. It is responsible for some deposits of iron, copper, nickel, chromium, and other metals.

4. How are mineral deposits discovered?

Detailed geologic surveys determine the location of mineral deposits. These surveys utilize a variety of instruments and measurements to help locate valuable mineral deposits. For example, the use of aerial or satellite photography is sometimes employed to disclose geologic formations associated with certain types of mineral deposits, while instruments that measure Earth’s magnetic field and gravity reveal other types of deposits. Seismographs can also be used to provide clues about mineral deposits.

Environmental Impacts Associated with Minerals 1. What are three harmful environmental effects of mining and processing minerals?

Chapter 15 Harmful environmental effects of mining and processing minerals include disturbance and damage to the land, and pollution of the surrounding air, soil, and water (i.e., acid mine drainage, tailings, etc.).

2. Are mining lands usually restored when the mine is no longer profitable to operate? Why or why not?

Derelict lands are extensively damaged due to mining but can be restored to prevent further degradation, and to make the land productive for other purposes. Land reclamation is expensive, and no federal law exists to require restoration of derelict lands other than those produced by coal mines. Therefore mining lands are rarely restored when a mine is no longer profitable to operate.

Minerals: An International Perspective 1. How does mineral consumption differ between industrialized and developing countries?

Highly developed countries consume a disproportionate share of the world’s minerals, but as developing countries industrialize, their need for minerals increases. For example, China’s mineral production and consumption is increasing rapidly.

2. How do mining experts differentiate between mineral reserves and mineral resources?

Mineral reserves are mineral deposits that have been identified and are currently profitable to extract. Mineral resources are any undiscovered mineral deposits or known deposits of low-grade ore that are currently unprofitable to extract.

Increasing the Supply of Minerals 1. What is a problem that limits mining known mineral deposits in Indonesia? In Siberia?

Many known mineral reserves have not yet been exploited. For example, the thick forests and malaria-carrying mosquitoes of Indonesia have made known mineral deposits difficult to access. Likewise, in Siberia, new technologies must be developed to make

Chapter 15 drilling in Antarctic waters possible during winter months, and to extract and separate the unusual combinations of minerals that are deposited there.

Using Substitution and Conservation to Expand Mineral Supplies 1. Explain the difference between reuse and recycling.

Reuse is the conservation of the resources in used items by using them over and over again. Recycling is the conservation of the resources in used items by converting them into new products.

2. What is sustainable manufacturing?

Sustainable manufacturing is a manufacturing system based on minimizing industrial waste.

Chapter 16 Biological Resources Lecture Outline: I. Biological Diversity A. A species is a group of organisms that are capable of interbreeding with one another to produce fertile offspring; to date, 1.8 million species have been scientifically named and described i. Variation among organisms is referred to as biological diversity (biodiversity) ii. Biodiversity takes into account genetic diversity and ecosystem diversity; it is much more than species richness B. Why we need organisms i. Ecosystem services and species richness 1. The activities of all organisms are interrelated 2. Species richness within an ecosystem provides the ecosystem with resilience ii. Genetic reserves 1. The maintenance of a broad genetic base is critical for each species’ long-term health and survival 2. Genetic uniformity results in increased susceptibility to pests and disease iii. Scientific importance of genetic diversity 1. Genetic engineering makes it possible to use the genetic resources of organisms on a wide scale 2. It has taken hundreds of millions of years for evolution to produce the genetic diversity found in organisms today iv. Medicinal, agricultural, and industrial importance of organisms v. Aesthetic, ethical, and spiritual value of organisms II. Endangered and Extinct Species A. Extinction is the elimination of a species from Earth; it is an irreversible loss i. Background extinction has occurred continuously during the time in which organisms have occupied the Earth ii. Mass extinctions have only occurred maybe five or six times iii. It is greatly accelerated by human activities; Earth’s biological diversity is disappearing at an unprecedented rate B. Endangered and threatened species i. A species that faces threats that may cause it to become extinct within a short period is considered an endangered species ii. A threatened species is a species whose population has declined to the point that it may be at risk of extinction iii. Characteristics of endangered species 1. Small (localized) ranges 2. Requiring a large territory 3. Living on islands (endemic species)

Chapter 16 4. Habitat fragmentation 5. Low reproductive success 6. Needing specialized breeding areas 7. Having specialized feeding habits C. Where is declining biological diversity the greatest problem? i. In the U.S., Hawaii and California have the highest levels of declining biological diversity ii. Tropical rain forests in South and Central America, central Africa, and Southeast Asia also face serious levels of declining biological diversity iii. Earth’s biodiversity hotspots 1. As many as 44% of all species of vascular plants, 29% of bird species, 27% of endemic mammal species, 38% of endemic reptile species, and 53% of endemic amphibian species live within biodiversity hotspots 2. There are 25 biological hotspots around the world D. Human causes of species endangerment i. In 2001, the Millennium Ecosystem Assessment gathered scientific information about ecosystem changes and the effects these changes have on human well-being; it found that biological diversity is declining due to several direct and indirect factors ii. Land use change - most species facing extinction today are endangered because of the destruction, fragmentation, or degradation of habitats by human activities iii. Invasive species 1. Biotic pollution often upsets the balance among the organisms living in a particular area and interferes with the ecosystem’s normal functioning 2. Foreign species whose introduction causes economic or environmental harm are called invasive species iv. Overexploitation 1. Species can become endangered or extinct as a result of deliberate efforts to eradicate or control their numbers 2. Illegal commercial hunting, or poaching, endangers many larger animals 3. Many unique animals and plants are threatened by commercial harvesting v. Pollution can degrade wilderness habitats that are “totally” natural and undisturbed III. Conservation Biology A. Conservation biology is the scientific study of how humans impact organisms and of the development of ways to protect biological diversity i. Conservation biologists believe it is more effective and, ultimately, more economical to preserve intact ecosystems in which many species liven than to work on preserving individual species one at a time ii. Conservation biologists use two problem-solving techniques to save organisms from extinction 1. In situ conservation (on site conservation)

Chapter 16 2. Ex situ conservation (off site conservation) B. Protecting habitats i. Protecting habitats is the single best way to preserve biological diversity ii. Currently more than 3,000 national parks, sanctuaries, refuges, forests, and other protected areas exist worldwide 1. Protected areas are not always effective in preserving biological diversity 2. Ecosystems in which biological diversity is greatest often receive little protection C. Restoring damaged or destroyed habitats i. In restoration ecology, the principles of ecology are used to help return a degraded environment to a more functional and sustainable one D. Zoos, aquaria, botanical gardens, and seed banks i. All play a critical role in saving individual species on the brink of extinction ii. Artificial insemination and embryo transfer are two techniques used in various zoos and aquaria to increase the numbers of rare species iii. Reintroducing endangered species to nature 1. The ultimate goal of captive-breeding programs is to produce offspring in captivity and then release them into nature so that wild populations are restored 2. Only one of every ten reintroductions is successful iv. Seed banks 1. More than 100 seed banks (gene banks) exist around the world and hold more than three million samples 2. Many types of plants cannot be stored as seeds, seeds do not remain alive indefinitely, cryopreservation is expensive, and stored plants remain stagnant in an evolutionary sense E. Conservation organizations i. Essential in the effort to maintain biological diversity ii. These groups help educate policymakers and the public IV. Conservation Policies and Laws A. The Endangered Species Act (1973) protects endangered and threatened species in the U.S. and abroad i. Currently more than 1,300 species in the U. S. are listed ii. It is illegal to sell or buy any product made from an endangered or threatened species iii. The ESA is one of the most controversial pieces of environmental legislation B. Habitat conservation plans (HCPs) i. Allow a landowner to “take” a rare species if the “taking” doesn’t threaten the survival or recovery of the threatened or endangered species on the property ii. HCPs do not provide any promise of recovery of rare species C. International conservation policies and laws i. The World Conservation Strategy (1980) is a plan designed to conserve biological diversity worldwide ii. The Convention on Biological Diversity (1992) was produced to decrease the rate of extinction of the world’s endangered species; it requires each signatory

Chapter 16 nation to inventory its own biodiversity and develop a national conservation strategy iii. CITES (Convention on International Trade in Endangered Species of Wild Flora and Fauna) helps control the exploitation of endangered species 1. Established in 1975 2. It bans hunting, capturing, and selling of endangered or threatened species and regulates the trade of organisms listed as potentially threatened V. Wildlife Management A. Wildlife management is an applied field of conservation biology that focuses on the continued productivity of plants and animals i. Most attention is focused on common organisms ii. It includes the regulation of hunting and fishing and the management of food, water, and habitat iii. Wildlife managers manipulate the plant cover, food, and water supplies of a specific animal’s habitat B. Management of migratory animals are usually established by international agreements C. Management of aquatic organisms i. Traditionally, the ocean’s resources have been considered common property, available to the first people to exploit them ii. Under such management, whales were harvested to the point of commercial extinction

Chapter 16

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Reintroducing Wolves

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: The wolf reintroduction program at Yellowstone National Park has been highly successful and should be expanded.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which, if either, provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions:

Chapter 16

Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Define extinction.

Chapter 16

Instructor Notes for In-Class Activity 2 Title:

Invasive Species In Your Area

Time: Materials: Handouts:

10 minutes prep; 25 – 40 minutes in class Internet access None

Procedures:

Divide students into groups of three or four.

Have them research • what (if any) native species have become endemic to your area • which of these thrive on their own, and which prefer areas where humans have made changes to the land • what species have been endangered by the invaders • what economic costs and benefits are associated with both the native species and the invasive species Then have them discuss what options are available for limiting opportunities for invasive species • Does your local government have abatement plans or practices?

• Are there any private efforts underway?

• Do the students think that there should be more efforts to control some or all of the invasive species? Why or why not If time permits, have groups report findings to the class, and then discuss as a group

Student Working in groups of 3 – 4, research Instructions: • what (if any) native species have become endemic to your area • which of these thrive on their own, and which prefer areas where humans have made changes to the land • what species have been endangered by the invaders • what economic costs and benefits are associated with both the native species and the invasive species Then have them discuss what options are available for limiting opportunities for invasive species • Does your local government have abatement plans or practices?

• Are there any private efforts underway?

• Do you think that there should be more efforts to control some or all of the invasive species? Why or why not Report your findings as requested by your instructor.

Specific Suggestions:

Some alternatives or supplemental exercises: • Invite a local wildlife or horticultural expert to talk to your class

Chapter 16 • •

Objectives:

Take a field trip to observe invasive and / or native species Have class members participate in a local invasive species abatement project

• Explain how invasive species endanger native species • Discuss the economic effects associated with invasive species

Chapter 16

Instructor Notes for In-Class Activity 3 Title:

Charismatic Megafauna

Time: Materials: Handouts:

5 minutes prep; 30 minutes in class Internet Access None

Procedures:

Have each student spend 5 – 10 minutes creating a list of as many endangered and extinct species that they are familiar with.

Have them read off their lists, and make a master list that groups these as non-mammalian animals, mammals, plants, and other Compare the number of species listed in each category.

Next, have students, working in groups of 3 – 4, research the number species that are threatened or have been known to go extinct. If possible have 8 groups working: 1. Extinct non-mammalian animals, 2. Extinct mammals, 3. Extinct plants, 4. Extinct other 5. Endangered non-mammalian animals, 6. Endangered mammals, 7. Endangered plants, 8. Endangered other How do these numbers match up to what the students know? Use this to lead a discussion on • Why do we know more about some groups than others?

• Are there advantages or disadvantages to this inconsistency (if any!)

• Could the species we know about represent “keystone” species?

• Does our knowledge help or hinder efforts to mitigate species extinction?

Student In the time allotted by your instructor, make a list of all the endangered Instructions: and extinct species you know about Note to instructor: After students have spent some time on this, and you have generated a list in class, divide students into groups and assign them one or more of the 8 areas listed above Working in groups of 3 – 4, research the number of species that either are endangered or have gone extinct from the category assigned by your instructor

Chapter 16 Specific Suggestions:

None

Objectives:

Describe how people conceive of endangered species and species extinction.

Chapter 16

Instructor Notes for In-Class Activity 4 Title:

Invasive Species

Time: Materials: Handouts:

20 minutes prep; 15 – 20 minutes in class Laminate invasive species on 3 x 5 cards – enough for one per student. and put them into a bag.

None

Procedures:

Have the students draw out of the bag an invasive species.

The students then research their invasive species and present to the class.

Some of the questions they might research are: Where did this species come from? How has it changed our environment? How can we correct the situation? Etc.

Student See above.

Instructions: Specific Suggestions:

None

Objectives:

Explain how invasive species endanger native species.

Chapter 16

Instructor Notes for In-Class Activity 5 Title:

Paper Clip Demonstration

Time: Materials: Handouts:

0 minutes prep; 15 – 20 minutes in class One new paperclip for each student None

Procedures:

Give each student a paper clip and ask them to straighten it out. When they think they have it as straight as they can make it, display it on the overhead projector. Keep adding paperclips until you and your class decide who has straightened their paper clip the most. Make sure the students remember or know whose paper clip is whose. After you have a winner, hand back the paper clips.

Take one of the paper clips and try to use it as a paper clip. The class will agree with you it is no longer useful as a paper clip.

After all the students have their straight paper clips back, tell them to turn them into a paper clip again. You may want to have a new paper clip on the overhead so they can see what their paper clip use to look like.

The students will desperately try to make them perfect, however, no paper clip will look like the new one. Place all the attempts up on the overhead so they can see the results of their recovery efforts.

Take a vote on whose paper clip is the best back to normal.

After you hand back all the paper clips take one of the good paper clips and try to use it as a paper clip. It will do the job, but it isn’t the best looking paper clip.

Moral of the story: Our environment is like the paper clips …once used it will never be back to new just like the paper clips. We can do all the remediation and get it almost perfect, but once the environment has been touched it will never be back to the way it was before man came and touch it. .

Student Step one: Take a paper clip and try to straighten it the best way you can.

Instructions: See who can have the straightest paper clip.

Step two: Now take your straight piece of wire that use to be a paper clip and turn it back to being a paper clip.

Specific Suggestions: Objectives:

None Describe restoration ecology.

Chapter 16

Answers to Critical Thinking and Review End of Chapter Questions: 1. Is biological diversity a renewable or nonrenewable resource? Why could it be seen both ways?

Ans: Answers will vary.

2. Aldo Leopold once wrote, “To keep every cog and wheel is the first precaution of intelligent tinkering.” How does his statement relate to biological systems?

Ans: Natural systems are so complex we can not completely understand all the components and interactions. If we remove any part of the system we stand a chance of destroying the whole system. It is best to leave the system intact so we do not make irreversible mistakes.

3. Describe five important ecosystem services provided by living organisms.

Ans: Ecosystem services are important environmental benefits, such as clean air to breathe, clean water to drink, and fertile soil in which to grow crops, that ecosystems provide. Bacteria and fungi perform the important ecosystem service of decomposition. Forests provide watersheds from which we obtain fresh water. Insects transfer plant pollen for reproduction. Soil organisms maintain soil fertility. Plant roots anchor in the soil and reduce soil erosion.

4. How is the current period of mass extinction different from all previous periods of mass extinction?

Ans: Species are presently becoming extinct at a rate of 100 to 1000 times the natural rate of background extinctions. Human activity, which was not a factor in previous mass extinctions, has greatly accelerated extinction. When humans invade an area, the habitats of many organisms are disrupted or destroyed contributing to their extinction.

5. List four characteristics common to many endangered species.

Ans: Characteristics that endangered species share are; having an extremely small (localized) range; requiring a large territory; living on islands; having a low reproductive success, often the result of a small population size or low reproductive rates; needing specialized breeding areas; and having specialized feeding habits.

6. What are biodiversity hotspots?

Ans: Biodiversity hotspots are relatively small areas of land that contain an exceptional number of endemic species and are at high risk from human activities.

7. What are the four main causes of species endangerment and extinction? Which cause do biologists consider most important?

Chapter 16 Ans: Scientists generally agree that the single greatest threat to biological diversity is land use change, which causes loss of habitat. The spread of invasive species, overexploitation, and pollution (including climate change from carbon dioxide pollution) are also important. There is little habitat that remains for many endangered species. The grizzly bear, for example, occupies about 2% of its original habitat in the lower 48 states of the United States. An invasive species, the water hyacinth, was deliberately brought from South America to the United States because it has lovely flowers. Today it has become a nuisance in Florida waterways, clogging them so that boats cannot easily move and crowding out native species. The Carolina parakeet, a beautiful green, red, and yellow bird endemic to the southern United States, was extinct by 1920, exterminated by farmers because it ate fruit and grain crops. Since the 1970s, many of the world's frog populations have dwindled or disappeared due to pollution in aquatic environments.

8. According to the cartoon on the right, what is one of the main causes of habitat loss in terrestrial ecosystems? INSERT CARTOON FROM PAGE 346 Ans: Answers will vary but should include habitat fragmentation, land use change, overexploitation, pollution, human population increase, and invasive species.

9. The following graph shows the effects of predation over a four week period on young bay scallops in three different marine seagrass environments. How does habitat fragmentation (patchiness) affect the percentage of young bay scallops lost to predation? Suggest a possible reason for this effect.

INSERT GRAPH FROM THIS QUESTION PAGE 347 Ans: Answers will vary.

10. If you had the assets and authority to take any measure to protect and preserve biological diversity, but could take only one, what would it be?

Ans: Answers will vary.

11. What invasive species pose problems in your area? How do they affect local ecosystems?

Ans: Answers will vary.

12 Give examples of in situ and ex situ conservation.

Ans: In situ conservation, including the establishment of parks and reserves, concentrates on preserving biological diversity in nature. Ex situ conservation involves conserving biological diversity in human-controlled settings. The breeding of captive species in zoos and the seed storage of genetically diverse plant crops are examples of ex situ conservation.

13. What are two advantages of using the principle of restoration ecology to return a degraded environment to a more functional one?

Chapter 16 Ans: Restoration ecology is the study of historical condition of a human-damaged ecosystem, with the goal of returning it as close as possible to its former state. Restoration of disturbed land creates biological habitats and has the additional benefits of regenerating soil damaged by agriculture or mining. It is also thought that restoration ecology might reduce extinctions.

14. What U.S. law provides legal protection to species to reduce their danger of extinction? Are species listed based on scientific reasons or on their economic value? Explain your answer.

Ans: The Endangered Species Act passed in 1973 authorized the Fish and Wildlife Service to protect endangered and threatened species in the United States and abroad. The ESA is geared more on saving a few popular or unique endangered species rather than the much larger number of less glamorous species.

15. Why is the Arctic snow goose such a challenge for U.S. wildlife managers? For Canadian wildlife managers?

Ans: The Arctic snow goose has become a major challenge for wildlife managers because its population expanded rapidly during the last two decades of the 20th century. The huge population of snow geese has damaged much of the Arctic's fragile coastal ecosystem as the geese forage there for a variety of plants and insects. Wildlife managers want to avoid a massive die-off of geese in the Arctic, a catastrophe that is unavoidable if the goose population is not brought under control. To reduce population numbers, U.S. and Canadian wildlife managers have increased the “taking” of snow geese by sport hunters. Animal rights groups oppose hunting and suggest that farmers in the winter range of the geese should modify their agricultural methods to reduce the amount of food available for the geese.

16. When people discuss the impact of global climate change, they usually mention polar bears or other charismatic animals. However, according to scientists at Botanic Gardens Conservation International, half of all plant species could be threatened by climate change. Most of these plants live on islands or mountains. Offer an explanation for why this is the case.

Ans: Biologists have documented that climate warming has caused many plant and animal species to shift their ranges toward the poles or to higher altitudes. For plants and animals that live on islands or mountain tops there may be no where to migrate to, leading to extinction of those species.

Answers to Review Questions Biological Diversity 1. What is biological diversity?

Biological diversity is the number and variety of Earth’s organisms; it consists of three components: genetic diversity (the variety within a species), species richness (the number of species), and ecosystem diversity (variety within and among ecosystems).

Chapter 16 2. What are three examples of ecosystem services provided by biological diversity?

Ecosystem services are important environmental benefits that ecosystems provide to people. Bacteria and fungi perform the important ecosystem service of decomposition.

Forests provide watersheds from which we obtain fresh water. Insects transfer plant pollen for reproduction. Soil organisms maintain soil fertility; and, plant roots anchor in the soil and reduce soil erosion.

Extinction and Species Endangerment 1. How do you distinguish between background extinction and mass extinction events?

Extinction is the elimination of a species from Earth. Background extinction is the continuous, low-level extinction of species. Mass extinctions are episodes in Earth’s history in which numerous species became extinct in a relatively short period.

2. What are endangered species? Threatened species?

An endangered species is a species that faces threats that may cause it to become extinct within a short period. A threatened species is a species whose population has declined to the point that it may be at risk of extinction. Endangered and threatened species often have limited natural ranges, low population densities, low reproductive rates, and specialized food or reproduction requirements.

3. What are biodiversity hotspots? Where are most biodiversity hotspots located?

Biodiversity hotspots are relatively small areas of land that contain an exceptional number of endemic species and are at high risk from human activities. Most hotspots are tropical, and nearly half are mostly or entirely islands.

4. What is the most significant cause of species endangerment and extinction?

Habitat destruction is the most significant cause of declining biological diversity because it reduces a species’ biological range. It is not, however, the only factor that can significantly contribute to species endangerment and extinction. For example, habitat fragmentation, a type of destruction in which large areas of habitat are broken into small, isolated patches, is also a significant cause. Other causes of declining biological diversity are the introduction of foreign species, overexploitation, and pollution.

5. How can an invasive species endanger native species?

Invasive species are foreign species that spread rapidly in a new area where they are free of predators, parasites, or resource limitation that may have controlled their population in their native habitat. Invasive species often upset the balance among the organisms living

Chapter 16 in that area – for example, by competing with native species for food or habitat – and interfere with an ecosystem’s normal functioning.

Conservation Biology 1. What is conservation biology?

Conservation biology is the scientific study of how humans impact organisms and of the development of ways to protect biological diversity.

2. Is restoration ecology an important aspect of in situ or ex situ conservation?

Restoration ecology is an important aspect of in situ conservation.

Conservation Policies and Laws 1. What is the Endangered Species Act? The Endangered Species Act (ESA) authorizes the U.S. Fish and Wildlife Service (FWS) to protect endangered and threatened species from extinction, both in the United States and abroad.

Wildlife Management 1. What is wildlife management? How do the goals of wildlife management and conservation biology differ?

Wildlife management is the application of conservation principles to manage wild species and their habitats for human benefit or for the welfare of other species. In contrast to conservation biology, which often focuses on threatened or endangered species, most attention in wildlife management is focused on common organisms.

Chapter 17 Land Resources Lecture Outline: I. Land Use A. One of the best ways to maintain biological diversity and to protect endangered and threatened species is by preserving or restoring the natural areas to which these organisms are adapted B. World land use i. Currently, humans use an estimated 3% of the world’s total land area for cities and 38% for agriculture ii. 29% remain as natural ecosystems with the potential for human development C. Land use in the United States i. 55% of U.S. land is privately owned, 3% by Native American tribes ii. 35% of U.S. land is owned by the federal government, 7% by local and state governments iii. Managing public and private land 1. Economic factors largely control land use 2. The wise-use movement believes that the primary purpose of federal lands is to enhance economic growth 3. The environmental movement views federal lands as a legacy of U.S. citizens II. Wilderness, Parks, and Wildlife Refuges A. Wilderness encompasses regions where the land and its community of organisms are not greatly disturbed by human activities and where humans visit but do not permanently inhabit i. The Wilderness Act of 1964 sets aside federally owned land as part of the National Wilderness Preservation System 1. These areas are to remain natural and unchanged for future generations to enjoy 2. They are given the highest protection of any public lands ii. Invasive species that have become established in wilderness have the potential to upset the balance among native species B. National parks i. The National Park System (NPS) was created in 1916; it currently administers 388 sites, 58 of which are national parks ii. One of the primary roles of the NPS is to teach people about the natural environment, management of natural resources, and history of a site by providing nature walks and guided tours of its parks iii. Threats to U.S. parks 1. Human activity (i.e., crime, vandalism, litter, pollution, etc.)

2. Declining populations of many species of mammals (i.e., bears) 3. Environmental stressors (i.e., pollution) iv. Natural regulation

Chapter 17 1. Natural regulation is a management policy that involves letting nature take its course 2. In Yellowstone, elk herds and fire are controlled by natural regulation C. Wildlife refuges i. The National Wildlife Refuge System was established in 1903 ii. It contains more than 535 refuges that aim to preserve lands and waters for the conservation of fishes, wildlife, and plants III. Forests A. Forests play an essential role in local and regional precipitation, and in regulating global biogeochemical cycles B. Forest management i. Traditional forest management often results in low-diversity forests where such monocultures cannot support the variety of organisms typically found in natural forests ii. Ecologically sustainable forest management (sustainable forestry) maintains a mix of forest trees by age and species, thus seeking to conserve forests for the long-term commercial harvest of timber and nontimber forest products 1. Wildlife corridors are protected zones that connect isolated unlogged or undeveloped areas 2. The purpose of wildlife corridors is to provide escape routes, migration routes, and larger territories for various animals iii. Harvesting trees 1. The U.S., Canada, Russia, Brazil, and China currently produce more than half of the world’s timber 2. 50% of harvested wood is burned directly as fuelwood or to make charcoal 3. Loggers harvest trees in several ways a. Selective cutting b. Shelterwood cutting c. Seed tree cutting d. Clearcutting C. Deforestation i. The most serious problem facing the world’s forests is deforestation ii. Causes include fires caused by drought and land-clearing practices, expansion of agriculture, construction of roads, tree harvests, insects and diseases iii. Deforestation often results in decreased soil fertility, increased soil erosion, increased sedimentation of waterways, formation of deserts, and species extinction D. Forest trends in the United States i. The U. S. has 155 national forests ii. In recent years temperate forests have expanded as the result of secondary succession iii. More than one half of U.S. forests are privately owned 1. The Forest Legacy Program is a provision of the 1990 Farm Bill that helps private land owners protect environmentally important forestlands from development

Chapter 17 2. Conservation easements are legal agreements that protect privately owned forest from development for a specified number of years E. Trends in tropical forests i. Tropical rain forests are found in Central and South America, Africa, and Southeast Asia 1. They occur in warm, moist climates 2. Most receive more than 200 cm of precipitation annually ii. Tropical dry forests receive less annual precipitation and are subject to a prolonged dry season 1. Trees typically shed their leaves and remain dormant in the dry season 2. They occur in India, Kenya, Zimbabwe, Egypt, and Brazil iii. Most of the remaining undisturbed tropical forests are being cleared and burned at a rate unprecedented in human history 1. Why are tropical rain forests disappearing? a. Population growth, economic, social and government factors, subsistence agriculture, commercial logging, cattle ranching, and mining b. Slash-and-burn agriculture is practiced by nearly 200 million subsistence farmers in tropical rain forests i. The first crop yield is often quite high ii. Soil productivity declines rapidly, and the process is repeated on a new tract of land 2. Why are tropical dry forests disappearing? a. Primarily for fuelwood b. Wood is used as heating and cooking fuel by much of the developing world F. Boreal forests and deforestation i. Boreal forests comprise the world’s largest biome; they occur in Alaska, Canada, Scandinavia, and northern Russia ii. They are currently the primary source of the world’s industrial wood and wood fiber and are harvested primarily by clearcut logging IV. Rangelands and Agricultural Lands A. Rangelands are grasslands that serve as important areas of food production for humans by providing fodder for livestock B. Rangeland degradation and desertification i. The carrying capacity (K) of a rangeland is the maximum number of animals the rangeland plants can sustain over an indefinite period without deterioration 1. When the K of the rangeland is exceeded, grasses and other plants are overgrazed 2. During dry periods (droughts) the K of the rangeland is considerably lower ii. Land degradation often results when overgrazing and extended drought occur at the same time 1. This results in the desertification of once fertile rangeland 2. Worldwide, desertification seems to be on the increase

Chapter 17 3. 135 million people are in danger of displacement as a result of desertification C. Rangeland trends in the United States i. Rangelands make up approximately 30% of the total land area in the U.S. and occur mostly in the western states 1. One-third is publicly owned; two-thirds is privately owned 2. The Bureau of Land Management guided by the Taylor Grazing Act (1934), the Federal Land Policy and Management Act (1976), and the Public Rangelands Improvement Act (1978) manages approximately 69 million of the 89 million hectares of public rangelands ii. Grazing fees on public rangelands 1. In 2004, the monthly grazing fee was $1.43 per cow on lands managed

by BLM and $1.52 per month on lands managed by the USFS 2. On private land the fee is more than $13 per cow D. Agricultural lands i. The U.S. has more than 121 million hectares of prime farmland ii. Much of the prime farmland is falling victim to urbanization and suburban sprawl V. Wetlands and Coastal Areas A. Wetlands are lands transitional between aquatic and terrestrial ecosystems i. Wetlands recharge groundwater, reduce damage from flooding, improve water quality, provide a habitat for many species (including many threatened and endangered species), and are recreational sites for human activity ii. The loss of wetlands is legislatively controlled by a section of the 1972 Clean Water Act 1. The federal government owns less than 25% of wetlands in the lower 48 states, the remaining 75% is privately owned 2. Although some private owners recognize the value of wetlands and voluntarily protect them, others are constrained by economic realities that dictate what they must do with their land 3. Congress authorized the Wetlands Reserve Program under the Food Security Act of 1985 to help restore and protect privately owned freshwater wetlands that were previously drained B. Coastlines i. Intact coastal wetlands moderate the effects of tides more inexpensively than engineering structures such as retaining walls ii. Few laws protect shoreline along bays and sounds iii. Coastal demographics 1. Many coastal areas are overdeveloped, highly polluted, and overfished 2. About two-thirds of the world’s population live within 150km of a coastline VI. Conservation of Land Resources A. Our ancestors considered natural areas as an unlimited resource to exploit B. Conservation strategies that set aside ecosystems are the best way to preserve an area’s biodiversity

Chapter 17

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Tragedy of the Commons

Time: Materials: Handouts:

5 minutes prep; 20 – 35 minutes in class Internet access None

Procedures:

Divide class into an even number of groups of 3 – 4.

Have half of the groups identify examples where the “tragedy of the commons” appears have explain an environmental problem.

Have the other half of the groups identify examples where we might expect to find a “tragedy of the commons,” but do not.

In each case, ask students look into possible explanations from the following list (or others) 1. Local, regional or national regulations 2. Economic influences 3. Lawsuits 4. Resilient ecosystems 5. Ethical or moral systems Regroup as a class and discuss what seems to determine whether a tragedy of the commons will occur. Can you make any generalizations, or do the cases seem to have little in common?

Student Working in groups of three or more, identify a case as assigned by your Instructions: instructor: • A case where a “tragedy of the commons” appears to have occurred or • A case where you might expect a “tragedy of the commons” but did not find it.

Try to determine what has caused the conditions you have observed. Are there governmental regulations? Have there been legal disputes / resolutions? Are there community ethical standards either missing or in play? Is property ownership well defined?

For any explanation you find, explain why you think it works as an explanation.

Specific Suggestions: Objectives:

None Describe “tragedy of the commons”

Chapter 17

Instructor Notes for In-Class Activity 2 Title:

History of Your Campus

Time: Materials: Handouts:

10 – 20 minutes prep; full class period Campus map None

Procedures:

As a class or in groups, research what the land that your campus currently occupies has been used for in the past. If it had a prior human use (or uses), identify each previous use. What type of land was it before disturbed by humans? Have the students think about possible alternative uses for this land (and, of course, an alternate location for campus)?

Compared to other types of land use, is a college campus more or less environmentally disruptive? How does it compare to agriculture, urban development, suburban development, commercial development and industrial development?

Student See above Instructions: Specific Suggestions:

You may wish to invite a local historian to participate

Objectives:

Discuss trends in land use in the United States.

Chapter 17

Instructor Notes for In-Class Activity 3 Title:

Land Use and Ownership in your State

Time: Materials: Handouts:

5 minutes prep; 25 minutes in class Internet access None

Procedures:

Divide students into groups, and have them identify: 1. How much of your state is owned by the Federal Government 2. How much of this land is park land and how much is military 3. Which federal agencies manage that land 4. What federal lands are used for, e.g. recreation, agriculture, grazing, protected wilderness 5. How much of this land is owned by your State 6. How much of the land is owned by local governments 7. How much is privately owned 8. How much land is used for agriculture If possible, establish trends. Are any of these categories increasing or decreasing? Why?

Student See above Instructions: Specific Suggestions:

If possible, invite a federal land agency representative to talk to your class

Objectives:

• •

Summarize current land ownership in the United States Classify federal land types and managing agencies

Chapter 17

Instructor Notes for In-Class Activity 4 Title:

Logging Camp

Time: Materials: Handouts:

5 minutes prep; full class period Internet Access None

Procedures:

Divide the students into four logging companies. Each has a particular way of harvesting trees. They will debate the best way to harvest trees and the pro’s and con’s of each. They will also find ways their company will protect the environment in which they harvest trees.

The four ways of harvesting trees: Selective cutting Shelterwood cutting Seed tree cutting clearcutting

Student You are a logging company and it is your mission to harvest trees in your Instructions: area. Please research the harvesting method assigned and how you and your company will be best for the environment. It is your goal to harvest the most trees, however, you must leave the environment better than you found it. How would you accomplish this?

You will present your method in a debate next class period.

Specific Suggestions: Objectives:

• • •

Define deforestation, include clear cutting, and relate the main causes of tropical deforestation.

Define national forests, stating which government agencies administer them and current issues of concern.

Relate how conservation easements help private landowners protect forest from development.

Chapter 17

Answers to Critical Thinking and Review End of Chapter Questions: 1. Name at least five ecosystem services provided by non-urban lands. Why is it difficult to assign economic values to many of these benefits?

Ans: Ecosystem services are important environmental benefits, such as clean air to breathe, clean water to drink, and fertile soil in which to grow crops, that ecosystems provide. Natural areas provide many ecosystem services, including watershed management, soil erosion protection, climate regulation, treatment of waste products, and wildlife habitat. These services are beyond any dollar amount that we could pay to have technology perform these services.

2. What are the main types of federally owned land in the United States? What uses are permitted on each type of land? What are current issues of concern for each type?

Ans: The main types of federally owned land include; the Bureau of Land Management (BLM), the Fish and Wildlife Service (FWS), the National Park Service (NPS) and the U.S. Forest Service (USFS). BLM manages multiuse areas, including rangeland. The federal government allows private livestock operators to use public rangelands for grazing; environmental groups want public rangelands managed for other uses, such as wildlife habitat, recreation, and scenic value. The National Wildlife Refuge System, administered by the FWS, contains habitat for the conservation of fishes, wildlife, and plants of the United States. Problems include overuse of some areas and the introduction of invasive species. The NPS administers national parks, which have multiple roles, including recreation and ecosystem preservation. Problems include overuse, high operating costs, imbalances in wildlife populations, and development of lands adjoining park boundaries. National forests have multiple uses, including timber harvest, livestock forage, water resources and watershed protection, mining, recreation, and habitat for fishes and wildlife.

Issues in national forests include confrontations over multiple uses, building logging roads with general tax revenues, and cutting old-growth forest.

3. Do you think additional federal lands should be added to the wilderness system? Why or why not?

Ans: Answers will vary.

4. Suppose a valley contains a small city surrounded by agricultural land. The valley is encircled by mountain wilderness. Explain why the preservation of the mountain ecosystem would support both urban and agricultural land in the valley.

Ans: Maintaining parcels of undisturbed land adjacent to agricultural and urban areas provides vital ecosystem services such as wildlife habitat, flood and erosion control, and groundwater recharge. Undisturbed land breaks down pollutants and recycles wastes. Natural environments provide homes for organisms. One of the best ways to maintain biological diversity and to protect endangered and threatened species is by preserving or restoring the natural areas to which these organisms are adapted.

Chapter 17 5. How would a park manager of a national park that adheres to natural regulation probably respond to a lightning-induced forest fire? to the establishment of a noxious invasive weed species?

Ans: Natural regulation is a park management policy that involves letting nature take its course most of the time, with corrective actions undertaken as needed to adjust for changes caused by pervasive human activities. Because fires are an integral part of the most forest ecosystems, wildfires in the park are not suppressed unless they threaten people or buildings. Park managers may intervene in other situations, such as to control invasive species or to restore native species.

6. How does a healthy forest affect a region’s hydrologic cycle? The carbon cycle?

Ans: Transpiration provides moisture for clouds, eventually resulting in precipitation. Thus, forests help maintain local and regional precipitation. Forests protect watersheds because they absorb, hold, and slowly release water; this moderation of water flow provides a more regulated flow of water downstream, even during dry periods, and helps control floods and droughts.

Forests play an essential role in regulating global biogeochemical cycles, such as carbon.

Photosynthesis by Earth’s approximately 1 trillion canopy trees removes large quantities of heat trapping carbon dioxide from the atmosphere and fixes it into carbon compounds. Forests thus act as carbon “sinks” that help mitigate global climate change.

7. Why is deforestation a serious global environmental problem?

Ans: Deforestation results in soil erosion and decreased soil fertility through rapid leaching of the essential mineral nutrients found in most forest soils. Deforestation contributes to the extinction of many species. Deforestation is thought to induce regional and global climate changes by contributing to an increase in global temperature by releasing carbon originally stored in the trees into the atmosphere as carbon dioxide, which enables air to retain heat.

8. What are four important causes of tropical deforestation?

Ans: Subsistence agriculture, commercial logging, cattle ranching, mining, and dam construction for hydroelectric power.

9. What are the environmental effects of clear-cutting on steep mountain slopes? on tropical rainforest land?

Ans: Clear-cutting destroys biological habitats and increases soil erosion, particularly on sloping land. Clear-cutting results in decreased soil fertility through rapid leaching of the essential mineral nutrients found in most tropical rainforest soils. Clear-cutting also leads to deforestation, which causes decreased soil fertility and increased soil erosion; impairs watershed functioning; contributes to the extinction of species; and may induce regional and global climate changes.

10. Describe the Forest Legacy Program

Chapter 17 Ans: The Forest Legacy Program is a provision of the 1990 Farm Bill that helps private landowners protect environmentally important forestlands from development. The program is managed by the USDA. The landowner sells some or all ownership rights to the U.S government which then holds a conservation easement.

11. Distinguish between rangeland degradation and desertification.

Ans: Desertification is degradation of once-fertile rangeland or tropical dry forest into nonproductive desert. Ecologists prefer to use the term degradation rather than desertification when referring to the effects of human activities in arid grasslands, whereas international policy makers prefer the term desertification.

12. Explain how certain tax and zoning laws increase the conversion of prime farmland to urban and suburban development.

Ans: Sometimes forest or agricultural land located near urban and suburban areas is taxed as potential urban land. Because of the higher taxes on this land, its owners fall under greater pressure to sell it, which ultimately hastens its development. However, if such land is taxed as forest or farmland, the lower taxes are an incentive for owners to hold onto the land and maintain it in its undeveloped condition. Thus, economic factors largely control land use.

13. What is a wetland? Why is the scientific definition of wetlands controversial?

Ans: Wetlands are lands that are usually covered by shallow water for at least part of the year and that have characteristic soils and water-tolerant vegetation. In 1989 a team of government scientists developed a comprehensive, scientifically correct definition of wetlands. It provoked an outcry from farmers and real estate developers, who perceived it as an economic threat to their property values. Largely in response to their criticisms, politicians attempted to narrow the definition of wetlands several times during the 1990s, removing marginal wetlands that were not as wet as swamps or marshes. The narrower definition, which relaxed rules on private land use, ignored decades of wetlands research and excluded about one-half of existing U.S. wetlands from protection.

14. What are three ecosystems services that wetlands provide?

Ans: Wetlands recharge groundwater, reduce damage from flooding, improve water quality, provide habitat for many species, and produce many commercially important products.

15. Describe current wetland protection policies in the United States and give their strengths and weaknesses.

Ans: The 1972 Clean Water Act, does a reasonably good job of protecting coastal wetlands but a poor job of protecting inland wetlands, which is where most wetlands are. The Emergency Wetlands Resources Act of 1986 authorized the FWS to inventory and map U.S. wetlands. These maps have many uses, such as planning for drinking water supply protection, planning for development projects, floodplain planning, and development of endangered species recovery

Chapter 17 plans. Congress authorized the establishment of the Wetlands Reserve Program (WRP) under the Food Security Act of 1985 and its amendments. The WRP is a voluntary program that seeks to restore and protect privately owned freshwater wetlands that were previously drained, such as those drained for conversion to cropland. Participants are offered financial incentives to restore the wetlands but the program is subject to budget cuts.

16. Should private landowners have control over what they wish to do to their land? How would you, as a landowner, handle land use decisions that may affect the public? Present arguments for both sides of this issue.

Ans: Answers will vary.

17. Explain the irony in the following cartoon.

INSERT CARTOON FROM THIS QUESTION PAGE 368 Ans: Answers will vary.

Answers to Review Questions Land Use 1. What are ecosystem services?

Ecosystem services are important environmental benefits that ecosystems provide to people. Ecosystem services provided by rural lands include wildlife habitat, flood and erosion control, and groundwater recharge.

2. What percentage of world land do urban areas occupy? How much is used for agriculture?

Urban areas account for only 3% of the world’s total land area, while 38% is used for agriculture.

Wilderness, Parks, and Wildlife Refuges 1. What is the U.S. National Wilderness Preservation System? Which state has the most wilderness land?

The U.S. National Wilderness Preservation System sets aside federally owned lands as designated wilderness in order to maintain natural habitats so they will be unimpaired for future generations to enjoy. More than one-half of the lands in the National Wilderness Preservation System lie in Alaska.

2. What are some current concerns of the National Park System?

Chapter 17 Current concerns of the National Park System include the same problems that plague urban areas. They include crime, vandalism, litter, traffic jams, and pollution of the soil, water, and air. In addition, thousands of resource violations, from cutting live trees and collecting plants, minerals, and fossils to defacing historical structures with graffiti and setting fires, are investigated in national parks each year.

3. What is the purpose of the National Wildlife Refuge System?

The purpose of the National Wildlife Refuge System is to preserve lands and waters for the conservation of fishes, wildlife, and plants.

Forests 1. What is sustainable forestry?

Sustainable forestry is the use and management of forest ecosystems in an environmentally balanced and enduring way. Sustainable forestry seeks to conserve forests for timber harvest, sustain biological diversity, prevent soil erosion, and preserve watersheds.

2. Why is the fact that U.S. national forests were created for multiple uses often a contentious issue?

National forests have multiple uses, including timber harvest, livestock forage, water resources and watershed protection, mining, recreation, and habitat for fishes and wildlife. Issues in national forests often include dilemmas over multiple uses due to the fact that these uses often infringe upon each other. For example, building logging roads with general tax revenues contradicts preservation of old-growth forest.

3. What is deforestation?

Deforestation is the temporary or permanent clearance of large expanses of forest for agriculture or other uses.

4. How do conservation easements protect forests from development?

A conservation easement is a legal agreement that protects privately owned forest or other property from development for a specified number of years. It helps private landowners protect environmentally important forestlands from development.

Rangelands and Agricultural Lands 1. What are rangelands? What is the carrying capacity of a rangeland?

Chapter 17 Rangelands are grasslands, in both temperate and tropical climates, that serve as important areas of food production for humans by providing fodder for livestock.

Rangelands may also be mined for minerals and energy resources, used for recreation, and preserved for biological habitat and for soil and water resources; they are not intensively managed. Provided the number of grazing animals is balanced with the rangeland’s carrying capacity, the rangeland remains a renewable resource. The carrying capacity of a rangeland is exceeded when grasses and other plants are said to be overgrazed.

2. What is desertification?

Desertification is degradation of once-fertile rangeland or tropical dry forest into nonproductive desert.

3. What human activity is threatening many acres of prime farmland?

Many acres of prime farmland are falling victim to urbanization and suburban sprawl.

Throughout the nation, prime farmland is being converted into parking lots, housing developments, and shopping malls.

Wetlands and Coastal Areas 1. What is a wetland? List at least five causes of wetlands destruction.

Wetlands are lands that are usually covered by shallow water for at least part of the year and that have characteristic soils and water-tolerant vegetation. They are lands transitional between aquatic and terrestrial ecosystems, and provide ecosystem services such wildlife habitat, purification of natural bodies of water, and recharging of groundwater. Despite their many ecosystem services, wetlands are often drained or dredged for other purposes, such as conversion to agricultural land. Other causes of wetland destruction include drainage for mosquito control, dredging for navigation, channelization, and construction of dams, dykes, or seawalls for flood control. Some wetlands are filled for solid waste disposal, road building, and residential and industrial development. Moreover, wetlands have been converted for aquaculture, mined for gravel, phosphate, and fossil fuels, and logged.

Conservation of Land Resources 1. What are three U.S. ecosystems that need protection?

According to the Biological Resources Discipline and the Defenders of Wildlife, the three most endangered ecosystems in the United States are the south Florida landscape, the southern Appalachian spruce-fir forests, and longleaf pine forests and savannas.

Other endangered ecosystems include the eastern grasslands, savannas, and barrens; the northwestern grasslands and savannas; the California native grasslands; coastal communities; southwestern riparian communities; southern California coastal sage scrub, and Hawaiian dry forest.

Chapter 17

Chapter 18 Food Resources Lecture Outline: I. Food and Nutrition A. 852 million people lack access to the food needed for healthy, productive lives; 3 billion people are malnourished i. The foods humans eat are composed of several major types of biological molecules necessary to maintain health 1. Carbohydrates 2. Proteins 3. Lipids ii. Minerals, vitamins and water are also required by humans to maintain health iii. Two common diseases result from malnutrition 1. Marasmus is progressive emaciation caused by a diet low in both total calories and protein 2. Kwashiorkor is malnutrition resulting from protein deficiency B. Human foods i. Just 15 species of plants provide the bulk of food for humans ii. Animals provide us with foods that are particularly rich in protein II. World Food Problems A. During the 1990s and early 2000s, world increases in food production barely kept pace with population growth B. Famines i. Famines are temporary, but severe food shortages due to crop failures caused by drought, war, flood, or some other catastrophic event ii. More people die from undernutrition and malnutrition than from starvation associated with famine C. Maintaining grain stockpiles i. World grain carryover stocks provide a measure of world food security ii. Stockpiles of grain have decreased each year since 1987 1. Stocks have dropped due to environmental conditions, declining investments in agricultural research, and an increase in the consumption of animal products 2. When food is scarce, prices increase and the risk of political instability is a real concern in poor nations D. Poverty and food: making food affordable for the poor i. The main cause of undernutrition and malnutrition is poverty; chronic hunger is more common in rural areas than in urban areas ii. Infants children, and the elderly are more susceptible to poverty and chronic hunger E. Economic and political effects on human nutrition i. It costs money to produce, store, transport, and distribute food 1. Countries with the greatest need for food cannot afford to pay for it

Chapter 18 2. Food-producing nations cannot afford to give it away ii. Getting food to the people who need it is largely a political problem iii. Developing countries need to become agriculturally self-sufficient III. The Principal Types of Agriculture A. Agriculture can be roughly divided into two types i. Industrialized agriculture (high-input agriculture) – relies on high inputs of capital and energy, produces high yields ii. Subsistence agriculture – produces just enough to feed oneself and one’s family, high input of manual energy, produces low yields 1. Various examples of subsistence agriculture include shifting cultivation, slash-and-burn agriculture, and nomadic herding 2. Intercropping allows for the growth of polycultures which produces higher yields than typical monocultures IV. Challenges of Producing More Crops and Livestock A. The effect of domestication on genetic diversity i. Genetic diversity contributes to a species’ long-term survival by providing the variation that enable each population to adapt to changing environmental conditions 1. Genetic diversity is often lost during the domestication of plants and animals 2. Most of the vegetable crops grown in the U.S. are of only a few varieties 3. When a disease breaks out in a domesticated plant or animal population, the entire uniform population is susceptible ii. The global decline in domesticated plant an animal varieties 1. To preserve older, more diverse varieties of plants and livestock, many countries are collecting germplasm 2. Germplasm includes seeds, plants, and plant tissues of traditional crop varieties, and the sperm and eggs of traditional livestock breeds 3. In 2004 the International Treaty on Plant Genetic Resources for Food and Agriculture was created to limit the genetic materials that agricultural companies are allowed to patent, and affirm the right of farmers to save, use, exchange, and sell farm-saved seeds B. Increasing crop yields i. Greater knowledge of plant nutrition has resulted in fertilizers that promote high yields ii. Use of pesticides and herbicides have also improved crop yields iii. Selective breeding programs have resulted in agricultural plants with more desirable features C. Increasing livestock yields i. The use of hormones and antibiotics increase animal production ii. Several studies link the indiscriminate use of antibiotics in humans and livestock to the evolution of bacterial resistance D. Genetic engineering i. Genetic engineering is a controversial technology that has begun to revolutionize medicine and has the potential to improve agriculture

Chapter 18 1. It differs from traditional breeding methods in that desirable genes from any organism can be used, not just those from the species of plant or animal being improved 2. It may produce food plants that will be more nutritious 3. Crop plants resistant to insect pests, viral diseases, drought, heat, cold, herbicides, or salty or acidic soils are being developed 4. The first genetically modified (GM) crops were approved for commercial planting in the U.S. in the early 1990s ii. The safety of genetic engineering 1. A growing body of evidence has determined that current GM crop plants are safe for human consumption and pose little threat to the environment 2. More research on the environmental impact of GM crops is required 3. The Cartagena Protocol on Biosafety (2003) lessens the threat of gene transfer from GM organisms to their wild relatives iii. The backlash against genetically modified foods 1. Inserted genes could spread in an uncontrolled manner from GM crops to weeds or wild relatives and thus harm natural ecosystems 2. Consumers might develop food allergies to GM foods iv. Should foods from genetically modified crops and livestock be labeled?

V. The Environmental Impacts of Agriculture A. The agricultural use of fossil fuels and pesticides produces air pollution B. Animal wastes and agricultural chemicals cause water pollution C. The quantity of manure produced by livestock factories can cause severe waste disposal problems and soil, surface water, and groundwater pollution D. Pesticide resistance is developing in many insect, weeds, and disease-causing organisms E. Land degradation results from industrialized agriculture F. Clearing grasslands and forests and draining wetlands to grow crops have resulted in habitat fragmentation, resulting in the decline of various species VI. Solutions to Agricultural Problems A. Sustainable agriculture i. Sustainable agriculture is not a single program but a series of programs adapted for specific soils, climates, and farming requirements 1. Integrated pest management (IPM) is used to minimize dependence on agricultural chemicals 2. Crop rotation, conservation tillage, and contour plowing help control erosion and maintain soil fertility ii. Organic agriculture uses no commercial inorganic fertilizers or pesticides and causes fewer environmental problems to the agroecosystem 1. Federal standards for certification of organically grown food went into effect in 2002 2. The trend from intensive techniques that produce high yields to method that focus on long-term sustainability of the soil has sometimes been referred to as the second green revolution B. Making subsistence agriculture sustainable and more productive

Chapter 18

VII.

i. Heavy mulching lessens soil infertility and erosion ii. Insect damage is reduced by planting several crops together iii. Legumes help restore nitrogen fertility to the soil Fisheries of the World A. Problems and challenges for the fishing industry i. No nation lays legal claim to the open ocean; overuse, overharvesting, and degradation result 1. Many countries have a policy of open management, in which all fishing boats of that country are given unrestricted access to fishes in national waters 2. The Magnuson Fishery Conservation Act (1977) regulates marine fisheries in the U.S. 3. The Magnuson-Stevens Fishery Conservation and Management Act (1996) requires protection of “essential fish habitat” ii. Longlines, purse-seine nets, trawl nets, and drift nets all have respective drawbacks to the health of the marine environment and bycatch B. Ocean pollution and deteriorating habitat i. The same ocean used to provide food is used as a dumping ground ii. Coastal areas are in high demand for recreational and residential development, and many coastal waters are polluted iii. Stormwater runoff from cities, agricultural areas, and roads is the single largest source of ocean pollution C. Aquaculture: fish farming i. Aquaculture is carried out both in fresh water and marine water (mariculture) ii. It produces finfish, shellfish, seaweeds, oysters, mussels, clams, lobsters, and crabs

Chapter 18

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Food Origins: Logging Consumption

Time: Materials: Handouts:

5 – 40 minutes prep (see below); 20 – 30 minutes in class None None

Procedures:

Have students keep a log of all the foods and ingredients that they eat for several day or a week.

▪ Ask them to, whenever possible, identify the nation or at least continent of origin ▪ For ingredients of uncertain origin, ask them to identify possible or probable geographic origins Use these logs to discuss how humans in one location can eat food from across the globe ▪ Is this more true for people in highly developed or less developed countries ▪ Is this more true for exotic foods or staples, or can such generalizations be made?

▪ To whom should the environmental impacts of agriculture be attributed—the farmer, the consumer, or both?

Student Keep track of the foods you eat for the amount of time assigned by your Instructions: instructor. Note that you need not keep track of the amount, but of the types. Include beverages.

For each, either identify the place of origin or, if that’s not possible, try to identify possible and probable geographic origins.

Specific Suggestions:

It might be useful to log your own food consumption for the week prior.

An alternative, quicker version is simply to ask students what they had for dinner the previous night, and try to surmise possible origins. Note that many spices have foreign origins. Beer and wine are often from other countries!

Objectives:

• •

Contrast industrialized agriculture with subsistence agriculture Describe geographic origins of foods

Chapter 18

Instructor Notes for In-Class Activity 2 Title:

Genetically Modified Food Consumption

Time: Materials: Handouts:

0 – 30 minutes prep; 5 – 15 minutes in class Examples of genetically modified products available from local stores None

Procedures:

Ask students for a show of hands: “how many of you have eaten genetically modified organisms?”

The correct answer is that most or all of them have.

Use this as a springboard to a discussion of the types of genetically modified crops available, the need (or lack of need) for labeling, and the future of genetically modified crops.

Student NA Instructions: Specific Suggestions:

Since labeling is NOT required in the US, it may be a challenge to track down known GM foods. You may want to supplement with foods labeled “non GM”, as ask students what, if anything, is implied about unlabeled foods.

Objectives:

Describe the nature and availability of genetically modified foods in the US.

Chapter 18

Instructor Notes for In-Class Activity 3 Title:

Genetic Modification: An Environmental Solution?

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: Genetic Modification of agricultural products should be actively pursued because they can substantially reduce environmental impacts of agriculture.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions:

Chapter 18 Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

• •

Identify the main components of human nutritional requirements.

Identify the potential benefits and problems with genetic engineering.

Chapter 18

Instructor Notes for In-Class Activity 4 Title:

Field trip to a dairy farm or pig farm

Time: Materials: Handouts:

10 – 20 minutes prep; full class period None None

Procedures:

Line up a field trip to a dairy farm so the students can observe what goes into production of milk and meat. Companies like Jimmy Dean sausage would be a good place to tour and they can explain how the animals are killed, what is the process etc. It is an eye opening experience. You probably wouldn’t be able to see where the animals are butchered but they tell you what all the animal parts go to and how the meat is processed.

Student See above Instructions: Specific Suggestions:

You may wish to invite a local meat or dairy farmer to class and they can explain the process of their operation.

Objectives:

• •

Describe the beneficial and harmful effects of domestication on livestock, defining germplasm in the process.

Identify the parts of animals used by humans outside of consumption.

Chapter 18

Instructor Notes for In-Class Activity 5 Title:

Give up meat for a week

Time: Materials: Handouts:

10 – 20 minutes prep; full class period None None

Procedures:

Have the student if given permission by their family and physician to give up meat and meat products for one week. Have them do a food diary on their experiences.

Student With your parents permission and the permission of your doctor, you are Instructions: to give up all meat and meat products for one week. Take notes on what you ate as a substitute and how do you feel throughout the week. Is this a diet you will stay on, or would you go back to your original diet of meat.

Specific Suggestions:

Before this activity, invite a vegetarian to class and have them instruct the class in meat substitutes and how it would feel to give up meat and meat products.

Objectives:

• •

Discuss ways in which food can be high in protein and will be a good substitute for meat.

Identify the main components of human nutritional requirements.

Chapter 18

Instructor Notes for In-Class Activity 6 Title:

Starving people

Time: Materials: Handouts:

10 – 20 minutes prep; full class period Map of the world None

Procedures:

Have the class research food agencies that help distribute food to people that do not have enough food to live or who cannot afford it. What are the policies these agencies follow? Is the food getting to the people?

How much are the people getting? Check with your local food bank and volunteer to see the need in your area. Are these agencies good or are they a scam on the American People?

Student See above Instructions: Specific Suggestions:

You may wish to invite a local food bank volunteer to your class to speak on their organization.

Objectives:

Differentiate among malnutrition, under nutrition and over nutrition.

Chapter 18

Answers to Critical Thinking and Review End of Chapter Questions: 1. What age group in humans is usually most affected by undernutrition, and famine? Why?

Ans: Infants, children, and the elderly are more susceptible to poverty and chronic hunger. In addition to poor physical development and increased disease susceptibility, children who are malnourished do not grow normally. Because malnutrition affects cognitive development, malnourished children do not perform as well in school as children who are well fed.

2. What is nutrition transition, and how does it relate to globalization?

Ans: Overnutrition is also emerging in developing countries, particularly in urban areas where people have adopted the unhealthy Western diet. The occurrence of both undernutrition and overnutrition in the same country is known as the nutrition transition.

As globalization spreads, so does the unhealthy Western diet.

3. Why does food insecurity occur? What are the links among poverty, food insecurity, and population issues?

Ans: There are several reasons why food insecurity exists. World grain stocks have decreased since all-time highs in the mid 1980’s and late 1990’s. Environmental conditions such as rising temperature, falling water tables, and drought have caused poor harvests. Many severe weather events have occurred. Consumption of beef, poultry, pork, and eggs have increased in China and other developing countries. Public investment in agriculture research have declined. World food problems are many, as are their solutions. The ultimate solution to chronic hunger is tied to achieving a stable population in each nation at a level that its environment can support. We are not going to be able to indefinitely increase the amount of food produced globally so we must control population growth globally.

4. Distinguish between shifting cultivation and slash-and-burn agriculture.

Chapter 18

Ans: Shifting cultivation is a form of subsistence agriculture in which short periods of cultivation are followed by longer periods of fallow (land left uncultivated) in which the land reverts to forest. Slash-and-burn agriculture is one of several distinct types of shifting cultivation that involves clearing small patches of tropical forest to plant crops. Because tropical soils lose their productivity quickly when they are cultivated, farmers using slash-and-burn agriculture must move from one area of forest to another every three years or so, so slash-and-burn agriculture is land-intensive.

5. Distinguish between intercropping and polyculture.

Ans: Intercropping is a form of intensive subsistence agriculture that involves growing a variety of plants simultaneously on the same field. Polyculture is a type of intercropping in which several kinds of plants that mature at different times are planted together.

6. What are two environmental problems associated with industrialized agriculture?

Ans: Soil erosion causes a decline in soil fertility as well as downstream sediment pollution.

Agricultural chemicals such as pesticides and commercial inorganic fertilizers cause air, water, and soil pollution. Land degradation is the natural or human-induced process that decreases the future ability of the land to support crops or livestock. Many insects, weeds, and disease-causing organisms have developed resistance to pesticides, forcing farmers to apply larger quantities.

7. What was the green revolution?

Ans: Using modern cultivation methods and the high-yielding varieties of certain staple crops to produce more food per acre of cropland is known as the green revolution.

8. Describe the environmental problems associated with farming each of these areas: tropical rain forests, hillsides, semiarid and arid regions?

Chapter 18

Ans: The majority of nutrients in a tropical rainforest is found in the trees. If the trees are removed for farming and the soil does not lie uncultivated long enough between farming cycles for it to recover soil fertility is reduced. Hillside farming is prone to soil erosion and loss of soil fertility. Farming in semiarid and arid region can lead to desertification and salinization of the soil from excess irrigation of poor-drainage soil.

9. Give at least three examples of ways that industrialized agriculture could be made more sustainable.

Ans: Sustainable agriculture avoids the continual use of antibiotics, large quantities of chemical pesticides, and high levels of commercial inorganic fertilizers. Industrialized agriculture could adopt the breeding of disease-resistant crop plants and the maintenance of animal health to limit the use of pesticides and antibiotics. Instead of using large quantities of chemical pesticides, sustainable agriculture controls pests by enhancing natural predator-prey relationships. For example, apple growers in Maryland monitor and encourage the presence of ladybird beetles in their orchards because these insects feed voraciously on European red mites, a major pest of apples. Crop selection helps control pests without heavy pesticide use. In parts of Oregon, apples are grown without major pest problems, but insects often infest peaches, whereas in western Colorado, apples have major pest problems but peaches do well. Therefore, apples would be the preferred crop for sustainable agriculture in Oregon, as would peaches in Colorado.

10. Current research has not demonstrated conclusively that organic foods are healthier to eat than foods grown by conventional agriculture. If that is the case, then what is the benefit of organic farming? (Hint: Is organic agriculture better for the environment? If so, how?)

Ans: In growing recognition of the environmental problems associated with industrialized agriculture, more and more mainstream farmers are trying some methods of sustainable agriculture. These methods cause fewer environmental problems to the agricultural ecosystem, or agroecosystem, than industrialized agriculture.

11. What is the problem with open management of ocean fisheries?

Chapter 18 Ans: Many nations have extended their limits of jurisdiction to 320 km (200 mi) offshore which removes many fisheries from international use. However, many countries have a policy of open management, in which all fishing boats of that country are given unrestricted access to fishes in national waters. Open management can therefore lead to overharvesting by each individual nation.

12. Explain why aquaculture is more like agriculture than it is like traditional fishing.

Ans: Aquaculture is more closely related to agriculture on land than it is to the fishing industry.

To optimize the quality and productivity of their “crops,” aquaculture farmers control the diets, breeding cycles, and environmental conditions of their ponds or enclosures. Aquaculturists try to reduce pollutants that might harm the organisms they are growing, and they keep them safe from potential predators.

13. How does a sustainable agricultural system resemble a natural ecosystem?

Ans: Sustainable agriculture is modeled after natural ecosystems, with their high biological diversity, biodegradation of materials, and maintenance of soil fertility. To this end, sustainable agriculture relies on beneficial biological processes and environmentally friendly chemicals that disintegrate quickly and do not persist as residues in the environment. The sustainable farm consists of field crops, trees that bear fruits and nuts, small herds of livestock, and even tracts of forest.

14. Climate scientists have observed a feedback loop involving soil moisture. Increasing temperatures dry the soil, and the dried soil exacerbates the heat. Is this an example of a positive feedback loop or a negative feedback loop? Explain your answer.

Ans: Positive feedback loop. A system in which A produces more of B which in turn produces more of A is an example of a positive feedback loop.

15. Read the cartoon. What point is the cartoonist trying to make?

Chapter 18 INSERT FIGURE FROM THIS QUESTION PAGE 391

Ans: The cartoonist makes the point that both environmental pollutants and overfishing were depleting the world’s fish stocks. The most serious problem for marine fisheries is that many marine species have been overharvested to the point that their numbers are severely depleted.

Answers to Review Questions World Food Security 1. Which is a more pervasive global issue – famine or chronic hunger? Explain your answer.

Famines are temporary, but severe, food shortages brought about by crop failures. These crop failures are most often caused by drought, war, floods, or other catastrophes. On the contrary, people who are chronically hungry lack access to the food they need to have healthy, productive lives on a consistent basis. It is estimated that more than 1.3 billion people in developing countries have incomes so low that they cannot afford to eat enough or the right kinds of food. Chronic hunger is an enduring condition and therefore, a more pervasive global issue.

2. What are world grain stocks?

World grain stocks are the amounts of rice, wheat, corn, and other grain stored by governments from previous harvests as a cushion against poor harvests and rising prices.

They supply a measure of food security if they do not fall below the minimum of a 70 days’ supply.

Food Production 1. What are the three most important food crops?

The three most important food crops are rice, wheat, and corn. These cereal grains provide about half of the calories that people consume.

2. What are three differences between industrialized agriculture and subsistence agriculture?

Industrialized agriculture requires a large capital input (for fossil fuels, equipment, and agricultural chemicals), and less land and human labor than traditional methods. It produces higher yields than subsistence agriculture, but causes several environmental problems (i.e., soil degradation and increased pesticide resistance in pests). Subsistence

Chapter 18 agriculture depends on labor (human and animal), and a large amount of land to produce enough food to feed oneself and one’s family. It incorporates techniques such as intercropping that discourage the buildup of any single pest species and help maintain soil fertility.

3. What are shifting cultivation, nomadic herding, and intercropping?

Shifting cultivation, nomadic herding, and intercropping are all forms of land-intensive subsistence agriculture. Shifting cultivation involves short periods of cultivation, followed by long periods of the land lying fallow. It is used to support relatively small populations. In nomadic herding, livestock are supported by land too arid for successful crop growth; herders wander freely over rangelands. Finally, intercropping involves growing a variety of plants simultaneously on the same field. Intercropping helps discourage the buildup of any single pest species to economically destructive levels.

Challenges of Producing More Crops and Livestock 1. Why does decreased genetic diversity in farm plants and animals increase the likelihood of economic disaster from disease?

Genetic diversity contributes to a species’ long-term survival by providing the variation that enables each population to adapt to changing environmental conditions. Therefore, decreases in genetic diversity in farm plants and animals could increase the likelihood of economic disaster from disease for two reasons: (1) the organisms do not have the genetic ability to survive the changing environmental conditions (i.e., disease exposure), and (2) most organisms would be genetically uniform, and thus ALL would be unable to survive changing environmental conditions (i.e., disease exposure). This, in turn, could lead to economic disaster.

2. What is the green revolution? What are some benefits and problems associated with the green revolution?

The green revolution is the use of modern cultivation methods, and the high-yielding varieties of certain staple crops, to produce more food per acre of cropland. The most beneficial aspect of the green revolution is the ability to provide adequate food supplies to support growing populations worldwide. Unfortunately, there are numerous problems associated with the green revolution. They include the energy costs built into this form of agriculture and the serious environmental problems caused by the intensive use of commercial inorganic fertilizers and pesticides.

3. Why are hormones and antibiotics routinely administered to livestock?

Hormones are routinely administered to livestock in order to help regulate bodily functions and promote faster growth. Likewise, the routine addition of low doses of antibiotics to livestock feed causes the animals to gain more weight than animals that do

Chapter 18 not receive antibiotics. This presumably occurs because the antibiotic-fed animals expend less energy to fight infections.

4. Give one advantage and one downside of GM crops.

Genetic engineering may produce food plants that are more nutritious, more resistant to insect pests and viral diseases, and more tolerant of drought, heat, cold, herbicides, and salty soil. On the downside, a complete analysis of the costs and benefits of long-term planting of genetically modified crops remain to be done, and thus the environmental impacts of these crops remain unknown. Moreover, some worry that consumers might develop food allergies to new genetically modified crops.

The Environmental Impacts of Agriculture 1. What are the major environmental problems associated with industrialized agriculture?

There are a myriad of major environmental problems associated with industrialized agriculture. They include: land degradation, pollution, soil erosion, pesticide resistance, and habitat fragmentation. To elaborate, land degradation is the natural or humaninduced process that decreases the future ability of the land to support crops or livestock.

Pesticides and commercial inorganic fertilizers cause air, water, and soil pollution. In addition, many insects, weeds, and disease-causing organisms have developed resistance to pesticides, forcing farmers to apply larger quantities. Soil erosion causes a decline in soil fertility as well as down-stream sediment pollution, and irrigation consumes huge quantities of fresh water. Moreover, expanding the amount of agricultural land due to industrialized practices has resulted in habitat fragmentation, which reduces the overall biological diversity of an ecosystem.

2. How does agriculture contribute to habitat fragmentation and land degradation?

Modern day agriculture involves clearing grasslands, cutting forests, and draining wetlands to grow crops. All of these processes result in habitat fragmentation, which can reduce the overall biological diversity of an ecosystem. In fact, many species have become endangered or threatened as a result of habitat loss caused by agriculture.

Agriculture also contributes to land degradation, especially when marginal lands are cultivated. Land degradation is the reduction in the potential productivity of a land.

Specifically, when marginal lands are cultivated, soil erosion and nutrient depletion result. Furthermore, soil erosion can cause a decline in soil fertility, and the sediments lost by erosion can damage water quality.

Solutions to Agricultural Problems 1. What is sustainable agriculture? What are some features of a sustainable farm?

Sustainable agriculture consists of agricultural methods that maintain soil productivity and healthy ecological balance while having minimal long-term impacts. Features of a

Chapter 18 sustainable farm include field crops, trees that bear fruits and nuts, small herds of livestock, and tracts of forest. Sustainable farming focuses upon biological processes (nutrient cycling, energy flow, and predator-prey relationships) rather than single actions (the effects of application of fertilizer on crop growth). It emphasizes a total agricultural ecosystem rather than single crop monocultures, and improves soil fertility by adding organic matter and managing soil biology. Sustainable farms aim to reduce soil erosion and manage wetlands carefully.

Fisheries of the World 1. How does bycatch reduce biological diversity in the ocean?

Bycatch consists of the fishes, marine mammals, sea turtles, seabirds, and other animals caught unintentionally in a commercial fishing catch. Because bycatch constitutes nearly 25% of all marine organisms caught, these species are also at risk of overharvesting even though they are not the target species. This reduction in population of various fishes, marine mammals, sea turtles, and seabirds can significantly reduce the biological diversity of an ocean.

2. What are some of the harmful environmental effects associated with aquaculture? With fishing?

Aquaculture is the growing of aquatic organisms for human consumption. Although aquaculture has an enormous potential to provide food, it can cause many environmental problems. Loss of coastlines and water pollution are the two most serious harmful environmental effects associated with aquaculture. Aquaculture has also been correlated with increases the incidence of parasites in wild fish populations and the overall net losses of wild fish due to the carnivorous nature of farmed fishes.

Fishing is associated with harmful environmental effects as well. Overharvesting of commercial fish populations and an overall decrease in the biological diversity of the world’s oceans are two of the most severe environmental problems that result from fishing. Various legislative acts have been put into effect to lessen the harmful environmental effects of fishing; they focus largely upon overall fishing regulation and protection of “essential fish habitat”.

Chapter 19 Air Pollution Lecture Outline: I. Atmosphere as a Resource A. Excluding water vapor, four gases comprise most of the atmosphere: nitrogen (78.08%), oxygen (20.95%) argon (.93%), and carbon dioxide (.04%) B. Other gases and particles, including pollutants, occur in much smaller concentrations II. Types and Sources of Air Pollution A. Air pollution consists of gases, liquids, or solids present in the atmosphere in high enough levels to harm humans, other organisms, or materials i. Much of the air pollution released by humans is concentrated in densely populated urban areas ii. Primary air pollutants are emitted directly into the atmosphere iii. Secondary air pollutants are formed when a primary air pollutant reacts with substances normally found in the atmosphere or with other air pollutants B. Major classes of air pollutants i. Particulate matter consists of thousands of different solid and liquid particles suspended in the atmosphere; it can have toxic or carcinogenic effects 1. Solid particulate matter – dust, soil particles, soot, lead, asbestos, etc.

2. Liquid suspensions – mist ii. Nitrogen oxides are greenhouse gases produced by the chemical interactions between atmospheric nitrogen and oxygen when a source of energy (i.e., fuel combustion) produces high temperatures 1. They inhibit plant growth and aggravate health problems (i.e., asthma) 2. They help produce photochemical smog and acid deposition iii. Sulfur oxides are gases produced by chemical interactions between sulfur and oxygen; they cause acid deposition, corrode materials, and irritate respiration iv. Carbon oxides tend to be colorless, odorless, tasteless greenhouse gases that are associated with global warming v. Hydrocarbons can injure respiratory tracts and cause cancer, and are important in the production of photochemical smog vi. Ozone is a pollutant in one part of the atmosphere but an essential component in another 1. Stratospheric ozone prevents much of the solar UV radiation from penetrating to the Earths’ surface 2. Ozone in the troposphere is a human-made air pollutant vii. The release of 180 hazardous air pollutants or air toxics is limited by the Clean Air Act Amendments of 1990 C. Sources of outdoor air pollution i. Mobile sources (transportation) – automobiles/trucks ii. Stationary sources (industries) – electrical power plants/industrial facilities D. Urban air pollution

Chapter 19 i. Smoke pollution primarily made up of sulfur oxides and particulate matter is often called industrial smog ii. Photochemical smog is a brownish-orange haze formed by chemical reactions involving sunlight, nitrogen oxide, and hydrocarbons iii. Both weather and topography affect air pollution 1. Under normal conditions, air circulation patterns prevent toxic pollutants from increasing to dangerous levels near the ground 2. During periods of temperature inversion, polluting gases and particulate matter remain trapped in high concentrations close to the ground III. Effects of Air Pollution A. Air pollution injures organisms, reduces visibility, and attacks and corrodes materials such as metals, plastics, rubber, and fabrics; it is involved in acid deposition, global temperature changes, and stratospheric ozone depletion B. Air pollution and human health i. Chronic respiratory diseases (i.e., emphysema and chronic bronchitis) may result from exposure to air pollution during respiratory illnesses ii. Health effects of specific air pollutants 1. Sulfur dioxide and particulate matter irritate the respiratory tract and cause airways to constrict, impairing the lung’s ability to exchange gases 2. Carbon monoxide binds irreversibly with iron in the blood’s hemoglobin, eliminating its ability to transport oxygen 3. Ozone causes burning eyes, coughing, and chest discomfort; it brings on asthma attacks and suppresses the immune system 4. It is estimated that 360 people out of every million Americans develop cancer as a result of air toxics iii. Children and air pollution 1. Air pollution is a greater health threat to children than it is to adults 2. Air pollution can restrict lung development in children 3. To obtain oxygen, children breathe about two times as much air per pound of body weight as do adults IV. Controlling Air Pollution in the United States A. Controlling air pollutants i. Historically “command and control” technologies have been used to reduce emissions ii. To help reduce emissions, some form of vapor recovery is required by gasoline sellers in most urban parts of the world iii. Lower combustion temperature in automobiles reduces the formation of nitrogen oxides iv. Careful handling of petroleum and hydrocarbons reduces air pollution from spills and evaporation B. The Clean Air Act i. This law authorizes the EPA to set limits on the amount of specific air pollutants permitted everywhere in the U.S.

Chapter 19 ii. The EPA has focused on six air pollutants (lead, particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides, and ozone) C. Other ways to improve air quality i. Reducing the sulfur content in gasoline ii. Making sure minivans, sport utility vehicles, and light pickup trucks have to comply with federal emission standards V. Ozone Depletion in the Stratosphere A. The relatively high concentrations of ozone in the stratosphere form a layer that shields the surface from much of the ultraviolet radiation (UV) coming from the sun B. The causes of ozone depletion i. Human-produced chlorine- and bromine-containing chemicals (i.e., chlorofluorocarbons - CFCs) lead to the accelerated destruction of ozone referred to as stratospheric ozone thinning ii. Halons, methyl bromide, methyl chloroform, and carbon tetrachloride also release chlorine or bromine and thus lead to ozone depletion C. The effects of ozone depletion i. Higher levels of UV radiation reach Earth’s surface ii. Excessive exposure to UV radiation is linked to eye cataracts, skin cancer, and weakened immunity iii. High levels of UV radiation may also damage crops and forests D. Facilitating the recovery of the ozone layer i. The Montreal Protocol (1987) stipulated a 50% reduction of CFC production by 1998 1. Industrial companies developed substitutes such as hydrofluorocarbons (HFCs) which do not attack ozone and hydrochlorofluorocarbons (HCFSs) which are not as destructive as CFCs 2. Production of CFC, carbon tetrachloride, and methyl chloroform was completely phased out in the U.S. in 1996 3. Developing countries phased out CFCs in 2005 ii. In the early 2000s, the first signs of recovery of the ozone layer were evident; the measurement of the rate of stratospheric ozone depletion was declining VI. Acid Deposition A. Acid deposition includes sulfuric and nitric acids in precipitation (wet deposition) as well as dry, sulfuric acid- and nitric acid-containing particles that settle out of the air (dry deposition) B. Measuring acidity i. An acidic solution has a pH less than 7 on the pH scale ii. The pH scale is logarithmic C. How acid deposition develops i. Acid deposition occurs when sulfur dioxide and nitrogen oxides are released into the atmosphere, combine with moisture to form acids, and then are deposited on land through rain, snow, or condensate ii. Acid deposition returns acids to the ground, causing the pH of surface waters and soil to decrease D. The effects of acid deposition

Chapter 19

VII.

VIII.

i. It affects living and non-living things and corrodes metals and building materials ii. Acid deposition and forest decline 1. Many living trees exhibit symptoms of forest decline 2. Forest decline appears to result from the combination of multiple stressors (i.e., acid deposition, tropospheric ozone, UV radiation, insect attack, drought, etc.)

E. The politics of acid deposition i. It does not only occur in the locations where the gases that cause it are emitted; it does not recognize borders ii. Pollution abatement issues are complex within one country but are magnified even more in international disputes F. Facilitating recovery from acid deposition i. Reducing emissions of sulfur dioxide and nitrogen oxides curbs acid deposition ii. Recovery often takes decades or centuries due to altered soil chemistry Air Pollution Around the World A. Environmental quality is usually a low priority in the race to develop B. Long-distance transport of air pollution i. Certain hazardous pollutants are distributed globally by atmospheric transport in a process known as the global distillation effect 1. The air toxics involved in this effect are persistent compounds that do not readily break down and so accumulate in the environment (i.e., PCBs, DDT, etc.)

2. The effect is more pronounced where it is colder, at higher latitudes and higher elevations ii. Movement of air pollution over the ocean Indoor Air Pollution A. The concentrations of certain indoor air pollutants may be two to five times greater (sometimes more than 100 times) than outdoors i. Examples include radon, cigarette smoke, carbon monoxide, nitrogen dioxide, formaldehyde, household pesticides, lead, cleaning solvents, ozone, and asbestos ii. The EPA considers indoor air pollution as one of the top five environmental health risks in the U.S. B. Radon i. Radon is a serious indoor air pollutant in many places in highly developed countries ii. It seep through the ground and enters building, where it can accumulate to dangerous levels iii. It harms the human body only when it is ingested or inhaled

Chapter 19

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Air Quality at Home and Away

Time: Materials: Handouts:

5 minutes prep; 15 – 25 minutes in class Internet access None

Procedures:

Divide students into three (for large classes, multiples of three) small groups. Have them research air pollution in: 1. Your town or city 2. Houston, Los Angeles and New York City 3. Mexico City, Beijing and Singapore For each of these areas, have them identify: 1. Major pollutants, including number of days that Federal or other standards are exceeded 2. Primary sources or causes of this pollution 3. Seasonality of pollution 4. Trends over the past three decades 5. Regulatory (or other) efforts to reduce air pollution 6. Biggest obstacles to improving air quality Have each group report its findings.

Student For the location or locations assigned by your instructor, identify Instructions: Major pollutants, including: 1. number of days that Federal or other standards are exceeded 2. Primary sources or causes of this pollution 3. Seasonality of pollution 4. Trends over the past three decades 5. Regulatory (or other) efforts to reduce air pollution 6. Biggest obstacles to improving air quality Provide a brief (3 – 5 minute) report back to your class.

Specific Suggestions:

NA

Objectives:

Describe major sources of, types of and management strategies for air pollution

Chapter 19

Instructor Notes for In-Class Activity 2 Title:

Toxicology, Epidemiology and the Effect of Particulates

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: Epidemiological evidence that all particulate matter is harmful to human health is less convincing than toxicological evidence that only some types of particles are harmful to human health.

Assign one group each to argue FOR (toxicologists’ side) or AGAINST (epidemiologists’ side) the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student

See above

Chapter 19 Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time: 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Describe the uncertainty about effects of particulate air pollution.

Chapter 19

Instructor Notes for In-Class Activity 3 Title:

Technological “Leapfrogging”

Time: Materials: Handouts:

5 minutes prep; 30 minutes in class Internet access None

Procedures:

The textbook states that, “air pollution is generally worse in developing countries than in highly developed countries.” One reason for this is that cleaner technologies can be more expensive than older, less polluting technologies. But this is not always the case: sometimes cleaner technologies can be cheaper, and sometimes developing countries can focus on less polluting industries as they develop. For example, running telephone answering services is far less polluting than producing lowquality steel.

Have students, working in groups of 3 – 4, identify • Several technologies that are less polluting and less expensive than earlier versions of the technology, and • Several developmental alternatives to highly polluting industries Have them discuss how these technologies could be adopted in developing countries, as well as the social, economic, infrastructure, or other limitations on their adoption.

Have each group report back to class on one or two most promising alternatives.

Student See above Instructions: Specific Suggestions:

NA

Objectives:

• •

Explain why air pollution is generally worse in developing countries than in highly developed countries Describe air pollution management options for developing countries

Chapter 19

Instructor Notes for In-Class Activity 4 Title:

So you want to smoke

Time: Materials: Handouts:

10 minutes prep 15 minutes class time 1 plastic straw in paper for each student None

Procedures:

Pass out one straw for each student. Have them take off the paper wrapping and throw it in the trash. When you give the signal “GO” have them put the straw in their mouth and plug their nose. They must only breathe air in and out through the straw. You might have them stand up and walk around exerting a little energy. After about two or three minutes, you can have them take the straw out of their mouth. You will hear a large gasp. Then tell them if they had emphysema they would not be able to take that large gasp, but that is all the air they will be able to breathe for the rest of their lives. The correlation is that the straw and the cigarette are about the same diameter. When smoking a cigarette, you do not think of it as your source of air. When you have emphysema that is your only source of air.

Student When the instructor says go, put the straw without the paper on it in your Instructions: mouth and plug your nose. You may walk around, however the only air you will get will be through the straw. When the instructor says stop, you may take the straw out of your mouth and take in a deep breath. If you start to feel dizzy, please take the straw out of your mouth and take a deep breath.

Specific Suggestions:

You might bring a cigarette to class and show the students the difference between the cigarette and the straw.

Objectives:

Illustrate the danger cigarettes cause on the human respiratory system.

Chapter 19

Instructor Notes for In-Class Activity 5 Title:

Air Pollution Cartoon Book

Time: Materials: Handouts:

10 minutes prep; outside of class Internet, newspapers, books etc None

Procedures:

As a class or in groups collect cartoons having to deal with air pollution.

Bring them to class and mount them on construction paper and place in a binder. Have the students present their cartoons to the class. This book can then be displayed in the library.

Student Collect cartoons, either on the internet, books, newspapers or other Instructions: sources that deal with air pollution. Bring the cartoon to class mounted on construction paper so that it will fit in the class binder. Be prepared to present your cartoon to the class.

Specific Suggestions: Objectives:

• • •

Discuss ways the public sees air pollution.

List ways air pollution is caused in our world today.

Summarize ways air pollution affects life on our world today.

Chapter 19

Answers to Critical Thinking and Review End of Chapter Questions: 1. The atmosphere of Earth has been compared to the peel covering an apple. Explain the comparison.

Ans: The atmosphere is a thin gaseous envelope that surrounds the Earth. Just like the apple peel the atmosphere is very thin compared to the larger body, the Earth. The atmosphere also protects the Earth like the peel protects the apple.

2. List the seven main kinds of air pollutants and briefly describe their sources and effects.

Ans: The main classes of air pollutants produced by human activities are particulate matter, nitrogen oxides, sulfur oxides, carbon oxides, hydrocarbons, ozone, and hazardous air pollutants.

Particulate matter is composed of solid particles and liquid droplets which are suspended in the atmosphere. They corrode metals, erode buildings, and soil fabrics. Nitrogen oxides (i.e., nitric oxide, nitrogen dioxide, and nitrous oxide) are associated with photochemical smog and acid deposition. Nitrous oxide is associated with global warming as well as stratospheric ozone depletion. Nitrogen oxides also corrode metals and fade textiles. Sulfur oxides, such as sulfur dioxide and sulfur trioxide, are associated with acid deposition and corrode metals and damage stone and other materials. Carbon oxides include carbon monoxide, which is poisonous, and carbon dioxide, a greenhouse gas. Hydrocarbons are solids, liquids, or gases associated with photochemical smog. One hydrocarbon, methane, is a greenhouse gas, and some hydrocarbons are dangerous to human health. Ozone is a pale blue gas that is both a pollutant in the lower atmosphere (the troposphere) and an essential component that screens out UV radiation in an upper atmosphere (the stratosphere). In the troposphere ozone reduces air visibility, causes health problems, stresses plants, and is a greenhouse gas. Hazardous air pollutants are air pollutants that are potentially harmful and may pose long-term health risks to people who live and work around chemical factories, incinerators, or other facilities that produce or use them.

3. Distinguish between primary and secondary air pollutants.

Ans: A primary air pollutant is a harmful substance, such as soot or carbon monoxide, that is emitted directly into the atmosphere. A secondary air pollutant is a harmful substance formed in the atmosphere when a primary air pollutant reacts with substances normally found in the atmosphere or with other air pollutants.

4. What are industrial smog and photochemical smog, and how do they differ?

Ans: Traditional London-type smog—that is, smoke pollution—is sometimes called industrial smog. The principal pollutants in industrial smog are sulfur oxides and particulate matter.

Another important type of smog is photochemical smog. This brownish-orange smog is called photochemical because light—that is, sunlight—initiates several chemical reactions that collectively form its ingredients. Both nitrogen oxides and hydrocarbons are involved in its formation.

Chapter 19 5. Why might global warming lead to more photochemical smog, even if emissions of nitrogen oxides and volatile organic chemicals remain constant?

Ans: Since ozone is created by a combination of high temperature, sunlight, hydrocarbons, water vapor and nitrogen oxides, some of those have to be controlled in order to reduce ozone, a major component of photochemical smog. Only two of these components, hydrocarbons and nitrogen oxides, can be controlled. With global warming, water vapor levels in the atmosphere may rise which in turn may lead to increased levels of photochemical smog.

6. What is a more stable atmospheric condition, cool air layered over warm air or warm air layered over cool air? Explain. What condition is a temperature inversion?

Ans: Warm air over cool air is more stable. As the sun increases surface temperature, the air near the ground is warmed. This heated air expands and rises to higher levels in the atmosphere.

Under normal conditions air circulation prevent toxic pollutants from increasing to dangerous levels near the ground. Temperature inversions occur when a layer of cold air is temporarily trapped near the ground by a warmer, upper layer. During periods of temperature inversion, polluting gases and particulate matter remain trapped in high concentrations close to the ground, where people live and breathe. Temperature inversions usually persist for only a few hours before being broken up by solar heating that warms the air near the ground. Sometimes, however, atmospheric stagnation caused by a stalled high-pressure air mass, allows a temperature inversion to persist for several days.

7. What urban areas have the worst air pollution in the world? Is this likely to change in the near future? Why or why not?

Ans: As developing countries become more industrialized they produce more air pollution.

Environmental quality is usually a low priority in the race to develop. Less expensive, outdated technologies are often used and air pollution laws are not enforced. Seven of the world’s worst cities for air pollution can be found in China. With rapid industrialization and a growing population, urban China faces some of the worst air quality in the world, with an estimated 400,000 premature deaths associated with air pollution in 2004. Automobiles, dust from construction sites, and electricity generated with coal outside of town, are the biggest culprits in Beijing. Although changes are being made for the upcoming Olympic Games and growing demand for cars and energy mean pollution is likely to continue to worsen.

8. Distinguish between the benefits of the ozone layer in the stratosphere and the harmful effects of ozone at ground level.

Ans: Ozone (O3) is a naturally occurring gas in the atmosphere. Human activities contributing to air pollution can cause its concentration in the lower troposphere to reach health-endangering levels; in the stratosphere, ozone is naturally produced, the ozone layer in the stratosphere is vital in shielding the Earth’s surface from harmful ultraviolet (UV) radiation.

9. The figure below depicts the thickness of the stratospheric ozone layer (measured in Dobson units) above New Zealand. In what year did the average yearly column of ozone above New Zealand first drop below 300 Dobson units? SEE FIGURE ON PAGE 418

Chapter 19

Ans: 1985 10. The amount of ozone-depleting chemicals released to the atmosphere have been reduced substantially since the late 1980s. Why has the concentration of stratospheric ozone not increased? Do we expect it to?

Ans: CFCs are extremely stable and those that are being used today will probably be depleting stratospheric ozone for at least 50 years. Full recovery of stratospheric ozone will probably take place sometime after 2050.

11. Discuss the harmful effects of acid deposition on materials, aquatic organisms, and soils.

Ans: The link between acid deposition and declining aquatic animal populations is well established. Toxic metals such as aluminum dissolve in acidic lakes and streams and enter into food webs. This increased concentration of toxic metals may explain how acidic water adversely affects fishes. Acid deposition also corrodes metals and building materials, damaging important building and monuments. Acid deposition returns acid to the ground, causing the pH of surface waters and soil to decrease.

12. Why is the global distillation effect likely to become an increasingly challenging problem in the future?

Ans: The global distillation effect is the process in which volatile chemicals evaporate from land as far away as the tropics and are transported by winds to higher latitudes, where they condense and fall to the ground. The pathway of movement is generally from warmer developing countries, where they are still used, to colder highly developed nations, where they condense and are deposited on land and surface water. Because these compounds can easily move across borders it will take worldwide cooperation to solve the problem.

13. One of the most effective ways to reduce the threat of radon-induced lung cancer is to quit smoking. Explain.

Ans: Cigarette smoking exacerbates the risk from radon exposure; about 90% of radon-related cancers occur among current or former smokers.

14. Conserving energy by reducing the rate at which indoor air is replaced with outdoor air can improve energy efficiency (less heating and cooling), but can contribute to indoor air pollution.

Explain how a systems approach to building design might help solve this problem.

Ans: A systems approach recognizes the need to conserve resources and protect the health of a building’s inhabitants. The building design would have properly placed intake vents for air systems, as well as filters on ventilation shafts. Detectors for radon and carbon monoxide should also be present.

Chapter 19 15. Explain why switching to low carbon intensity fuels can reduce local and regional air pollution as well.

Ans: Reducing the carbon content of fuels simultaneously reduces other air pollutants with local or region effects. Ground-level ozone, nitrogen oxides, and particulates are the most impacted, but some reductions in sulfur oxides can be expected as well. The expected effect on ozone is twofold. First, less carbon also means fewer of the precursors to ozone. Second, reducing carbon should mean less atmospheric warming. Since ozone formation requires not only chemicals but also high temperatures, less warming will mean fewer days with high enough temperatures to allow ozone formation.

Answers to Review Questions The Atmosphere as a Resource 1. What are the primary constituents of the atmosphere?

Excluding water vapor and trace gases that include air pollutants, four gases comprise the atmosphere: nitrogen, oxygen, argon, and carbon dioxide.

Types and Sources of Air Pollution 1. What are some effects of each of the seven major classes of air pollutants?

The main classes of air pollutants produced by human activities are particulate matter, nitrogen oxides, sulfur oxides, carbon oxides, hydrocarbons, ozone, and hazardous air pollutants. Particulate matter corrodes metals, erodes buildings, and soils fabrics.

Nitrogen oxides are associated with photochemical smog, acid deposition, metal corrosion, and textile fading. In particular, nitrous oxide is associated with global climate change as well as stratospheric ozone depletion. Sulfur oxides are also associated with acid deposition; they corrode metals, and damage stone and other materials. Carbon oxides include carbon monoxide, which is poisonous, and carbon dioxide, a greenhouse gas. Hydrocarbons include methane, which is a greenhouse gas. Some hydrocarbons are dangerous to human health. Ozone is a pollutant in the lower atmosphere (the troposphere) and an essential component that screens out UV radiation in the upper atmosphere (the stratosphere). In the troposphere, ozone reduces air visibility, causes health problems, stresses plants, and is a greenhouse gas. Lastly, hazardous air pollutants are potentially harmful and can pose long-term health risks to people who live and work around chemical factories, incinerators, or other facilities that produce or use them.

2. How and why have tropospheric ozone concentrations changed in southern California since 1955?

Ozone is a pollutant in the tropospheric atmosphere. It is created by a combination of high temperatures, sunlight, hydrocarbons, water vapor, and nitrogen oxides. In order to reduce ozone concentrations in southern California, laws were passed to reduce

Chapter 19 hydrocarbons and nitrogen oxides. This was done by placing restrictions on combustion engines, oil refineries, charcoal lighter fluid, and spray paints. These restrictions have since reduced ozone concentrations in the area more than threefold.

Effects of Air Pollution 1. What is the general effect of air pollution on the body’s immune system?

Air pollutants irritate the eyes, inflame the respiratory tract, and suppress the immune system. Specifically, sulfur dioxide, particulate matter, and nitrogen dioxide constrict airways, impairing the lungs’ ability to exchange gases. Likewise, carbon monoxide combines with hemoglobin and reduces its ability to transport oxygen; carbon monoxide poisoning can cause death. Adults at greatest risk from air pollution include those with heart and respiratory diseases.

2. Why are children particularly susceptible to the effects of air pollution?

Air pollution is a greater health threat to children than it is to adults, in part because air pollution impedes lung development. In addition, a child has a higher metabolic rate than an adult and needs more oxygen. To obtain this oxygen, a child breathes more air – about two times as much air per pound of body weight as an adult; meaning that a child breathes in more air pollutants into their lungs than adults.

Controlling Air Pollution in the United States 1. What are some technologies that reduce air pollution? Some policies?

Various technologies have been developed to reduce air pollution. They include electrostatic precipitators, scrubbers, phase I and II vapor recovery technologies, and catalytic converters. Policies aimed at reducing air pollution include the Air Pollution Control Act of 1955 and The Clean Air Act of 1970 (with updates in 1977 and 1990).

2. What is the U.S. Clean Air Act, and how has it reduced outdoor air pollution?

Air quality in the United States has slowly improved since passage of the Clean Air Act in 1970. This law authorizes the Environmental Protection Agency to set limits on how much of specific air pollutants are permitted in the United States. The most dramatic improvement has been the decline in lead in the atmosphere. Levels of sulfur oxides, nitrogen oxides, ozone, carbon monoxide, volatile organic compounds (many of which are hydrocarbons), and particulate matter have also been reduced.

Ozone Depletion in the Stratosphere 1. What is the stratospheric ozone layer?

Chapter 19 The stratospheric ozone layer is a naturally produced, essential component in the stratosphere, which encircles our planet some 10 to 45 km above the Earth’s surface. The relatively high concentrations of ozone in the stratosphere form a layer that shields the surface of Earth from much of the ultraviolet (UV) radiation coming from the sun.

2. How does stratospheric ozone thinning occur?

Stratospheric ozone thinning is the accelerated destruction of ozone, a naturally occurring gas, in the stratosphere, by human-produced chlorine- and bromine- containing chemicals. Both chlorine- and bromine-containing substances catalyze ozone destruction. The primary chemicals responsible for release of chlorine in the stratosphere are chlorofluorocarbons (CFCs). Halons (fire retardants), methyl bromide (pesticides), and methyl chloroform and carbon tetrachloride (industrial solvents) also release chlorine or bromine, and thus lead to ozone depletion.

Acid Deposition 1. What is acid deposition and what causes it?

Acid deposition is a type of air pollution that includes acid that falls from the atmosphere as precipitation or as dry acid particles. Acid deposition occurs when sulfur dioxide and nitrogen oxides are released into the atmosphere. These pollutants react with water to produce sulfuric acid, nitric acid, and nitrous acid.

2. How is forest decline related to acid deposition?

Forest decline is the gradual deterioration and often death of many trees in a forest; air pollution and acid deposition contribute to forest decline in many areas. However, although acid deposition correlates well with areas experiencing tree damage, it is only partly responsible for forest decline. It appears that a combination of multiple stressors – acid deposition, tropospheric ozone, UV radiation (which is more intense at higher altitudes), insect attack, drought, and climate change – contribute to forest decline.

Air Pollution Around the World 1. Is air pollution worse in highly developed or in developing countries? Why? Air quality is worse in developing countries due to rapid industrialization, a growing number of automobiles in those countries, and lack of emissions standards.

2. What is the global distillation effect? What kinds of air pollutants are involved in the global distillation effect?

The global distillation effect is the process in which volatile chemicals evaporate from land as far away as the tropics and are transported by winds to higher latitudes, where

Chapter 19 they condense and fall to the ground. The air pollutants that are involved in the global distillation effect include persistent compounds such as polychlorinated biphenyls (PCBs, industrial compounds) and dichlorodiphenyltrichloroethane (DDT, a pesticide).

Indoor Air Pollution 1. What are the major sources of indoor air pollution?

The major sources of indoor air pollution are radon, tobacco smoke, carbon monoxide, nitrogen dioxide (from gas stoves), formaldehyde (from carpeting, fabrics, and furniture), household pesticides, lead, cleaning solvents, ozone (from photocopiers), and asbestos.

Chapter 20 Global Climate Change Lecture Outline: I. Introduction to Climate Change A. Scientists have researched global climate change for the past 50 years i. Temperatures have increased over the past century ii. It is unlikely that this warming can be explained by natural causes iii. The U.N. Intergovernmental Panel on Climate Change (IPCC) published its Fourth Assessment Report (2007) concluding that human produced air pollutants have caused most of the climate warming observed over the last 50 years 1. Depending on the assumed emission scenario and on the intensity of the climatic response, the IPCC report projects a 0.2°C increase in average global temperature in each of the next two decades 2. By 2100, temperatures are expected to be from 1.8°C to 4.0°C higher B. The cause of global climate change i. The accumulation of carbon dioxide (CO2), methane (CH4), nitrous oxides (N2O), chlorofluorocarbons (CFCs), and tropospheric ozone (O3) in the atmosphere have been correlated with global climate change ii. Greenhouse gases (i.e., water vapor) absorb infrared radiation and exert a positive feedback on the climate that amplify warming 1. CO2 accounts for 60% of the increased heat retention caused by greenhouse gases 2. The natural trapping of heat in the atmosphere is referred to as the greenhouse effect 3. Radiative forcing is the capacity of a gas to affect the balance of energy entering and leaving the atmosphere C. Other pollutants cool the atmosphere i. Atmospheric aerosols tend to cool the atmosphere in what is called the aerosol effect 1. The sulfur-laden haze caused by aerosols reflects incoming sunlight back into space 2. Sulfur pollution likely contributes to regional cooling 3. Sulfur haze cools the planet only during daytime ii. The actual aerosol effect on the climate is relatively uncertain due to various types of aerosols; sooty aerosols tend to absorb radiation D. Developing and using climate models i. Many interacting factors, such as winds, clouds, ocean currents, and albedo affect climate ii. Scientists develop simulation models to test how the Earth system works 1. A climate model is only as good as its representation of the physical laws and processes

Chapter 20 2. Limitations include representation of clouds and changes that are likely to occur as the climate changes a. Low-lying clouds could act as a negative feedback and decrease the amount of warming b. High, thin cirrus clouds could intensify warming E. Unpredictable and extreme climate change II. The Effects of Global Climate Change A. As more and more CO2 is absorbed by the ocean, ocean water chemistry will become more acidic B. Melting ice and rising sea levels i. During the 20th century sea level rose about 0.2 m due to thermal expansion ii. A 20 year study demonstrates that the area of ice-covered ocean in the Arctic has decreased 1. The arctic ice pack is thinning rapidly, losing 40% of its volume in less than three decades 2. Melting ice has a positive feedback on global heating iii. Mountain glaciers are melting at accelerating rates iv. Greenland is losing about 44 km3 of ice each year, up from estimates of 8.3 km3 in the period 1993-1998 v. The largest potential source of ice loss is the Antarctic Ice sheet C. Changes in precipitation patterns i. Computer models indicate, as global climate change occurs, precipitation patterns will change causing various problems in different geographic areas 1. More frequent droughts 2. Heavier snow and rainstorms 3. More frequent flooding ii. Changes in precipitation patterns are likely to affect the availability and quality of fresh water in many locations iii. The frequency and intensity of storms over warm surface waters will likely increase D. Effects on organisms i. An increasing number of studies report measurable changes in the biology of plant and animal species as a result of climate warming 1. Earlier flowering times for plants 2. Earlier migrations of aquatic species 3. Shifting of geographic ranges 4. Dramatic reduction in the abundance of oceanic zooplankton, and subsequent disruption of food webs ii. Many species may become extinct due to their inability to adapt to global climate change, especially species that occupy polar seas, coral reefs, mountain ecosystems, coastal wetlands, and tundra iii. Plants will be severely impacted by global climate change due to the fact that they cannot move about when environmental conditions change E. Effect on human health i. Most of the health effects associated with climate change are indirect and have multiple, interrelated causes

Chapter 20 ii. Heat waves can cause an increased number of heat-related illnesses and deaths, particularly in the elderly F. Effects on agriculture i. Agricultural productivity is likely to go up due to increased CO2 levels ii. Certain agricultural pests and disease-causing organisms will probably proliferate and reduce yields iii. Frequency and duration of droughts may increase iv. Soil moisture may decrease v. Changes in agriculture will be geographically and demographically uneven G. International implications of global climate change i. Dealing with global climate change is complicated by social, economic, and political factors that vary from one country to another ii. Highly developed versus developing nations 1. Because developing countries have less technical expertise and fewer economic resources, they are less likely to be able to respond to the challenges of global climate change 2. Currently highly developed countries produce about ten times more CO2 emissions per person than developing countries 3. The booming economic growth and greater population in developing countries threaten to overwhelm the world with CO2 emissions as they become industrialized H. Links among global climate change, ozone depletion, and acid deposition i. Researchers have begun to study the interactions of environmental problems simultaneously ii. Environmental studies often examine only single issues III. Dealing with global climate change A. CO2 emissions produced today will still be around in the 22nd century and beyond B. To avoid the most dangerous consequences of climate change, many studies indicate that the atmospheric CO2 concentration needs to be stabilized at 550 ppm C. There are two basic ways to attempt to manage global climate change i. Mitigation ii. Adaptation D. Carbon capture and storage i. Carbon sequestration would help to slow the growth in carbon emissions ii. Carbon management is a new, unproven technology; its costs and potential ecological effects will have to be studies fully before it is adopted on a large scale iii. Sequestering carbon in trees 1. Removes atmospheric CO2 from the air by planting and maintaining forests 2. It is estimated that trees can remove 10 to 15% of the excess CO2 in the atmosphere, but would only provide a short term benefit E. Adaptation to global climate change i. People living in coastal areas could be moved inland ii. Dikes and levees could be constructed to protect coastal land iii. Crops could be substituted for those more adapted to warmer climates

Chapter 20 F. International efforts to reduce greenhouse gas emissions i. At least 174 nations have now signed the U.N. Framework Convention on Climate Change developed at the 1992 Earth Summit; its goal is to stabilize greenhouse gas concentrations ii. George W. Bush withdrew the U.S. commitment to the Kyoto Protocol in 2001 on the grounds that its implementation via a tax or permit system aimed at reducing greenhouse gases would create an unacceptable economic burden for the nation

Chapter 20

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Positive and Negative Feedbacks

Time: Materials: Handouts:

10 minutes prep; 15 – 25 minutes in class None Feedback list

Procedures:

Have students individually complete the worksheet below, which asks which of a list of climate change factors represent positive and negative feedbacks. In each case, students should briefly explain their answers.

As a group work through each of the issues, then generate a list of additional positive and negative climate feedbacks.

Student Complete the worksheet Instructions: Specific Suggestions:

Call for a show of hands for “positive” and “negative” feedback for each item. Solicit explanations from amongst those students with correct answers!

Objectives:

Describe positive and negative feedbacks associated with global climate change.

Chapter 20 In-Class Activity 1: Handout List of Positive and Negative Feedbacks Associated with Climate Change 1. For each of the following, circle whether the effect will have a positive or negative feedback effect on global climate change. Briefly explain your answer in the space provided.

2. Provide some additional examples of positive and negative feedbacks

Increasing temperatures may lead to increased evaporation and thus increased cloud cover Positive / Negative Explanation:

Increasing temperatures may lead to less ice at the poles and high elevations Positive / Negative Explanation:

Increasing temperatures means that water can hold less dissolved CO2 Positive / Negative Explanation:

Increasing temperature and CO2 means that plants may grow more quickly Positive / Negative Explanation:

Increasing temperatures means that pants and animals will decompose more quickly Positive / Negative Explanation:

Chapter 20 In-Class Activity 1: Handout (Page 2) List of Positive and Negative Feedbacks Associated with Climate Change Increasing temperatures may lead people to use more air conditioning in the summer Positive / Negative Explanation:

Increasing temperatures may lead people to use less heating in the winter Positive / Negative Explanation:

Increasing temperatures may lead to increased wildfires Positive / Negative Explanation:

Additional Example: Positive / Negative Explanation:

Additional Example: Positive / Negative Explanation:

Additional Example: Positive / Negative Explanation:

Chapter 20

Instructor Notes for In-Class Activity 2 Title:

How Should Highly Developed Countries Respond to Climate Change?

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

While there is strong agreement in the scientific community that climate change is happening and that human activity is a primary cause, there is little agreement in the policy community about what, if anything, should be done to abate climate change. Highly developed countries have historically been the main source of greenhouse gasses.

Statement: Highly developed countries should act quickly and substantially to reduce their current and future greenhouse gas emissions.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

Chapter 20 3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Explain options for reducing future anthropogenic climate change.

Chapter 20

Instructor Notes for In-Class Activity 3 Title:

Vehicle Use On and To Campus

Time: Materials: Handouts:

10 minutes prep; full class period Campus Map None

Procedures:

Divide students into small groups.

Have each group go out on campus and explore vehicle use.

Have them describe how vehicles are used both to move things and people around the campus and to get people and things to and from campus.

Be sure they assess: 1. What types of vehicles are used (include motor vehicles and nonmotor vehicles) 2. How efficiently are they being used?

3. What fraction of the students, faculty and staff drive to campus?

4. What fraction of the students, faculty and staff live on or walk to campus?

5. What fraction of the students, faculty and staff take public transit to campus?

6. What fraction of the students, faculty and staff bicycle, skateboard, etc to campus 7. What other forms of transportation are used to get people to and from campus?

8. What alternatives are there to the current vehicle use? Could golf carts be used on campus instead of cars or trucks? Could the public transit system be better designed?

9. How much do students, faculty and staff pay for parking permits?

Does this encourage or discourage driving?

Have students return and discuss as a group.

• How easy/difficult would it be to change student/faculty/staff transportation habits?

• How much CO2 savings could be achieved on your campus through transportation changes?

Student See above Instructions: Specific NA Suggestions: Objectives: Explain how changes in individual and institutional behavior can ameliorate climate change

Chapter 20

Instructor Notes for In-Class Activity 4 Title:

Temperature changes

Time: Materials: Handouts:

10 –15 minutes prep; full class period Access to the internet None

Procedures:

Divide the class into groups of 2 or 3 students. Assign each group a country or continent. As a group, research the assigned country or continent and check the temperature of that country or continent for the last year, 10 years, 100 years, has the temperature changed? What are the temperature ranges for that country or continent? Make a chart and have the groups present to the rest of the class. Are all the groups finding out the same information or are temperature changes locally.

Student See above Instructions: Specific Suggestions: Objectives:

• •

Discuss some of the potential effects of global climate change.

Describe temperature ranges in different countries or continents.

Chapter 20

Instructor Notes for In-Class Activity 5 Title:

Disaster Research

Time: Materials: Handouts:

10 – 20 minutes prep; full class period Internet Use None

Procedures:

Assign or have the students pick a disaster for example hurricanes, tornadoes, earthquakes, volcano, typhoon, blizzards, tsunami etc. Have them research the then present to the class. What is the disaster? How does it effect the environment? How can we prepare for it? When do they occur? Are they getting worse? Which disasters are the deadliest etc.?

Student See above Instructions: Specific Suggestions:

Compile all the information on a matrix and you will have a presentation for a poster presentation.

Objectives:

Discuss the types of disasters and their impact on the environment.

Chapter 20

Instructor Notes for In-Class Activity 6 Title:

Mitigation Research

Time: Materials: Handouts:

10 – 20 minutes prep; full class period Internet Access None

Procedures:

Divide the class into groups of three, one group for each type of mitigation management. As a group they will research their type of mitigation and become expert consultants in this type of mitigation.

Present their information to the class and then follow with a discussion as to which type of mitigation is best and where is the type used. Is it possible to only have one type of mitigation or are all three types needed for the different areas. Is there a cost factor? How would countries adjust to the different types and which type would be more successful for the earth as a whole.

Student See above Instructions: Specific Suggestions: Objectives:

• •

Discuss Mitigation of global climate change.

Compare and contrast the three types of mitigation.

Chapter 20

Answers to Critical Thinking and Review End of Chapter Questions: 1. One of Socolow and Pacala’s wedges (see introduction) involves reducing the number of miles driven by each car by 50% (they predict 2 billion cars worldwide by 2056). Considering what you know about how people drive now, how could people reduce their driving by 50%?

How would this affect their lives?

2. How does the enhanced greenhouse effect impact global climate?

Ans: The enhanced greenhouse effect is the additional warming produced by increased levels of gases that absorb infrared radiation. Based on numerous studies, the IPCC, a United Nations panel of experts, concluded in 2007 that human-produced air pollutants have caused most of the recent climate warming. Climate scientists conclude that the world will almost certainly warm substantially during the 21st century. Scientists are less certain about what regional patterns may emerge.

3. What are climate models? What inputs are used when building them? What can they tell us about future climates?

Ans: Climate models are systems of mathematical equations that are used to simulate the atmosphere of the earth. Climate models are used for weather forecasting, understanding the climate, and projecting climate change. Climate models take into account incoming energy from the sun as well as outgoing energy from the earth. Climate models are used to project what the climate will be like in a few decades or a century from now.

4. What two factors contribute to sea-level rise?

Ans: The thawing of mountain glaciers and polar ice caps and sheets due to the decade-long trend of atmospheric warming.

5. What effect has increased evaporation due to climate change had on regional weather patterns.

Ans: Precipitation patterns will change resulting in some areas having more frequent droughts.

Other areas will experience heavier snow and rainstorms resulting in more frequent flooding.

6. Austrian biologists who study plants growing high in the Alps found that plants adapted to cold-mountain conditions migrated up the peaks as fast as 3.7 m (12 ft.) every decade during the 20th century, apparently in response to climate warming. Assuming that warming continues during the 21st century, what will happen to the plants if they reach the tops of the mountains?

Ans: As warming accelerates in the 21st century, many species will undoubtedly become extinct, particularly those with narrow temperature requirements, those confined to small, specialized habitats, and those living in fragile ecosystems. Other species may survive in greatly reduced numbers and ranges. Ecosystems considered at greatest risk of loss of species in the short term are polar seas, coral reefs, mountain ecosystems, coastal wetlands, and tundra.

Chapter 20

7. Suggest some ways in which seasonal changes in plant growth in Canada might affect songbirds in Mexico.

Ans: An increasing number of studies report measurable changes in the biology of plant and animal species as a result of climate warming. Such effects range from earlier flowering times for plant species to migrations of aquatic species. Although generally not a benefit to humans, some species will come out of global climate change as winners, with greatly expanded numbers and range. Those organisms considered most likely to prosper include certain weeds, insect pests, and disease-carrying organisms common in a wide range of environments. Insects and songbirds that migrate between Mexico and Canada could greatly increase in numbers if plant growth in Canada increases, this could cause problems for both communities.

8. What aspects of adaptation to global climate change would be easier for highly developed nations, and which for developing nations? Explain.

Ans: Although developed nations have huge amounts of coastal infrastructure at risk, many developing nations may experience the greatest impacts of global climate change. Because developing countries have less technical expertise and fewer economic resources, they are the ones likely to be least able to respond to the challenges of global climate change. Most developing countries see increased use of fossil fuels as their route to industrial development and resist pressure from highly developed nations to decrease fossil fuel consumption.

9. Based on what you’ve read in this chapter and the information on environmental economics in Chapter 2, explain how a global market for CO2 permits would function.

Ans: A carbon tax (See Chapter 2) could be levied against users of fossil fuels, based on the proportion of CO2 emissions produced per unit of heat released when the fuel is burned. Because coal is carbon-intensive, it would have the highest carbon taxes.

10. Insurance companies that provide policies for hurricanes and other natural disasters may shift hundreds of millions of dollars of their investments from fossil fuels to solar energy. On the basis of what you have learned in this chapter, explain why insurance companies consider such an investment in their best interest.

Ans: Shifting investments into solar energy technology would help reduce CO2 emissions which in turn would mitigate global climate change. Intensity of hurricane and other natural disasters has been increasing with climate change costing insurance companies millions of dollars, so it would be in their best interest to help stop these changes.

11. Some environmentalists contend that the wisest way to “use” fossil fuels is to leave them in the ground. How would this affect air pollution? global climate change? energy supplies?

Ans: Leaving fossil fuels in the ground would improve air pollution, and mitigate global climate change. But it would greatly decrease our energy supplies.

Chapter 20 12. What do the relationships among acid deposition, stratospheric ozone, and climate change tell us about the importance of thinking about the environment as a system?

Ans: All of these processes are interconnected. How far UV radiation, which has increased because of the thinning ozone layer, penetrates water is related to the presence of dissolved organic material. Organic material acts like a sunscreen, absorbing UV radiation so that it only penetrates a few inches. A warmer climate can increase evaporation from the watersheds for lakes, thereby reducing the amount of water flowing into a lake if precipitation does not increase sufficiently. Because most of a lake's dissolved organic compounds wash in from the watershed, even a slightly drier climate reduces how much organic material is present in the lake. As a result, UV radiation penetrates deeper into the lake. In addition, acid from acid deposition causes organic matter to clump and settle on the lake floor. In turn, the removal of organic material from the water allows UV radiation to penetrate farther, causing greater impacts for life in the lake.

13. John Holdren, science advisor to President Obama, argues that there are three possible human responses to climate change: mitigation, adaptation and suffering. Discuss the implications of this on people today and people 50 years from now.

Ans: Adaptation focuses on learning to live with to the environmental changes and societal consequences brought about by global climate change. While some have objected to the development of strategies to adapt to climate warming because they feel this implies an assumption or an acceptance that global climate change is unavoidable, the widespread observations that the climate is changing make clear that adaptation will be unavoidable. For people today adaptation may mean little or no change but for people 50 years from now agricultural zones will need to be shifted, sea level changes will force people to move and sewage systems to be rebuilt.

14. Sea level is expected to rise about 0.4 m (1.3 ft) by 2100 (the blue line in the figure above).

However, the prediction is uncertain; different models suggest that we can expect anywhere from 0.2 m (green line) to 0.6 m (red line). Which, if any, of these increases should we prepare for?

Explain your choice.

INSERT GRAPH FROM THIS QUESTION PAGE 436 Ans: Answers will vary

Answers to Review Questions Introduction to Climate Change 1. What is the enhanced greenhouse effect, and what are the five main greenhouse gases that contribute to it?

The enhanced greenhouse effect is the additional warming produced by increased levels of gases which result from human activities. The five main greenhouse gases that contribute to it are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), chlorofluorocarbons (CFCs), and tropospheric ozone (O3).

Chapter 20 2. How do climate models project future climate conditions?

Climate models are computer models that describe the global climate as a system. The models divide the atmosphere and oceans into small, three-dimensional parts and evaluate the effects of changes in one part on adjacent parts. These models incorporate feedbacks that influence such factors such as temperature, wind patterns, cloud moisture, and ice cover. Running these models based on different predicted levels of CO2 leads to projections of possible future climate conditions.

3. Why are unpredictable and extreme climate changes important?

Unpredictable and extreme climate changes are important because they help climate models project expected or most likely outcomes and ranges of possible outcomes. They can help modelers predict ranges that could be troubling and cause serious disruptions, which could benefit humans in their preparedness for similar future events.

The Effects of Global Climate Change 1. How do melting ice and thermal expansion of water contribute to sea-level rise?

More than half of recent and projected sea-level rise is associated with the fact that water expand as it heats up; this is known as thermal expansion. During the 20th century, thermal expansion contributed about 0.2 m (8 inches) to the overall rise in sea level. The thawing and melting of glaciers and land-based ice sheets is the other major contributor to sea-level rise.

2. How has climate change impacted precipitation? What other future precipitation changes do we expect?

Many researchers agree that climate change is an important determinant of precipitation patterns. Recently, in fact, precipitation and other weather patterns have begun to shift, with increased flooding in some locations and increased intensity of tropical storms in others. In effect, several studies have concluded that climate change is most likely responsible for the recent flooding in England. As for the future, computer models indicate that, as global climate change occurs, precipitation patterns will change, causing some areas to have more frequent droughts. At the same time, heavier snow and rainstorms are projected to cause more frequent flooding in other areas.

3. What are some effects of climate change already experienced by organisms, including humans?

Globally, organisms are affected by changes in temperature, precipitation, ocean acidification, sea-level rise, and other climate change-related effects. They are also affected by changes in other populations – for example, some organisms have reacted more acutely to the early arrival of spring than others, disrupting food webs throughout

Chapter 20 many different ecosystems. Also related to climate change, humans have been affected by heat waves, flooding, and sea-level rise, as well as changes to agriculture.

Dealing with Global Climate Change 1. What are some examples of mitigation and adaptation?

Mitigation is an action or actions that diminish the causes of climate change. Examples include burning less oil, natural gas, and coal; planting trees; and sequestering carbon dioxide. Adaptation consists of preparatory actions intended to diminish the effects of a changing climate. Examples include moving people away from shorelines and changing agricultural practices.

2. How do perspectives on climate change of highly developed countries differ from those of less developed countries?

Highly developed and developing countries have different interests, needs, and perspectives. Most developing countries see increased use of fossil fuels as their route to industrial development and resist pressure from highly developed countries to decrease fossil-fuel consumption. Developing countries often ask why they should have to take actions to curb CO2 emissions when the rich industrialized nations historically have been the main cause of the problem. In contrast, highly developed countries argue that the booming economic growth and much greater number of people living in developing countries threaten to overwhelm the world with CO2 emissions as the developing countries become industrialized. Developing countries respond that even when they are producing half of the world’s CO2 emissions, the situation will still be unequal because 80% of the world’s population living in developing countries will be producing only half of the emissions.

Chapter 21 Water Pollution Lecture Outline: I. Types of Water Pollution A. Water pollution is a global problem that varies in magnitude and type of pollutant from one region to another B. Water pollutants are divided into eight categories which are rarely exclusive i. Sewage 1. The release of wastewater from drains or sewers; includes human wastes, soaps, and detergents 2. Sewage generates enrichment and biochemical oxygen demand, two serious environmental problems 3. Eutrophication: an enrichment problem a. An oligotrophic body of water has clear water and supports small populations of aquatic organisms due to the minimal levels of nutrients in its unenriched waters b. An body of water enriched by inorganic plant and algal nutrients (i.e., phosphorus) is said to be eutrophic; it usually contains large populations of aquatic animals c. Over vast periods, oligotrophic bodies of water become eutrophic naturally d. Eutrophication can also be accelerated by human-induced processes (i.e., artificial eutrophication) ii. Disease-causing agents 1. Municipal wastewater usually contains many bacteria, viruses, protozoa, parasitic worms, and other infectious agents that cause human or animal diseases 2. Monitoring for sewage a. Periodic tests are made for the presence of sewage in our water supplies b. To test for the presence of E. coli in water, the fecal coliform test is performed iii. Sediment pollution 1. Clay, silt, sand, and gravel are sediments suspended and carried in water 2. Sediment pollution comes from erosion of agricultural lands, forest soils exposed by logging, degraded stream banks, overgrazed rangelands, strip mines, and construction 3. Sediment pollution reduces light penetration, covers aquatic organisms, brings insoluble toxic pollutants to the water, and fills in waterways iv. Inorganic plant and algal nutrients

Chapter 21 1. Chemicals such as nitrogen and phosphorus stimulate the growth of plants and algae a. Nitrates and phosphates come from sources such as human and animal wastes, plant residues, atmospheric deposition, and fertilizer runoff from agricultural and residential land b. Inorganic plant and algal nutrients are harmful in large concentrations 2. The dead zone in the Gulf of Mexico a. Fertilizer runoff from Midwestern fields and manure runoff from livestock operations considerably pollute the Gulf of Mexico b. This creates a dead zone where no life exists i. In 2002 it measured more than 22,000 km2 ii. It creates hypoxia in various invertebrates and mollusks v. Organic compounds 1. Organic compounds are chemicals that contain carbon atoms (i.e., sugars, amino acids, oils) 2. Most of the thousands of organic compounds found in water are human produced chemicals (i.e., pesticides, solvents, industrial chemicals, plastics, etc.) a. Most seep from landfills into surface water and groundwater b. Farm and residence runoff contributes large amounts of pesticides into surface water and groundwater c. Some industries dump organic compounds directly into waterways 3. The effect on human health of ingesting drinking water containing traces of these chemicals are generally unknown vi. Inorganic chemicals 1. Inorganic chemicals are contaminants that contain elements other than carbon (i.e., acids, salts, and heavy metals) a. They do not easily degrade b. Industries, mines, irrigation runoff, oil drilling, and urban runoff from storm sewers are the main sources of inorganic chemicals 2. Lead a. Lead contaminates the soil, surface water, and groundwater when incinerator ash is dumped into ordinary sanitary landfills b. Ingestion of additional amounts of lead from pesticide and fertilizer residues occur through consumption of produce, food cans soldered with lead, and dinnerware c. Lead can come from the corrosion of old lead water pipes or of lead solder in newer pipes 3. Mercury a. Most mercury pollution comes from human activities i. Coal-fired power plants

Chapter 21 ii. Municipal waste and medical waste incinerators release mercury iii. Smelting of metals such as lead, copper, and zinc iv. Precipitation after household trash containing batteries, paints, and plastics are burned in incinerators b. Mercury bioaccumulates in the muscles of tuna, swordfish, sharks, mackerel, and marine mammals c. Prolonged exposure to methyl mercury compounds causes kidney disorders and severely damages the nervous and cardiovascular systems of animals vii. Radioactive substances 1. Radioactive substances contain atoms of unstable isotopes that spontaneously emit radiation 2. Mining and processing of radioactive materials such as uranium and thorium emit radioactive substances into water; radiation from natural sources can also pollute groundwater viii. Thermal pollution 1. Thermal pollution occurs when heated water produced during certain industrial processes is released into waterways 2. Such a rise in temperature can have chemical, physical, and biological effects a. Less oxygen dissolves in warm water than in cool water, affecting the dissolved oxygen levels of dependent aquatic life b. Warmer temperatures can affect the reproductive cycles, digestion rates, and respiration rates of aquatic organisms II. Water Quality Today A. Water pollutants come from both natural sources and human activities B. The sources of water pollution are classified into two types i. Point source pollution is discharged into the environment through pipes, sewers, or ditches from specific sites ii. Nonpoint source pollution (polluted runoff) is caused by land pollutants that enter bodies of water over large areas (i.e., agricultural runoff, mining wastes, municipal wastes, construction sediments, soil erosion) C. Water pollution from agriculture i. Agriculture is the leading source of water quality impairment of surface waters nationwide, causing 72% of water pollution in rivers ii. Soil conservation methods both conserve soil and reduce water pollution D. Municipal water pollution i. Sewage and urban runoff from storm sewers are the main pollutants produced by cities and towns ii. Combined sewer overflow flows into nearby waterways without being treated when too much water enters the system; nearly 1.2 trillion gallons of combined sewer overflow are discharged into U.S. waterways every year E. Industrial wastes in water i. Food processing industries produce organic wastes ii. Pulp and paper mills produce toxic compounds and sludge

Chapter 21 iii. The electronics industry produces wastewater containing high levels of heaby metals F. Groundwater pollution i. Roughly half of the people in the U.S. obtain their drinking water from groundwater; its quality has become a concern ii. Cleanup of polluted groundwater is costly, takes years, and in some cases is not technically feasible G. Water pollution in other countries i. 1.4 billion people lack access to safe drinking water ii. 2.9 billion do not have access to adequate sanitation systems iii. Worldwide, 250 million cases of water-related illnesses occur each year; 5 million result in death III. Improving Water Quality A. Water quality is improved by removing contaminants from the water supply before and after it is used B. Purification of drinking water i. The chlorine dilemma 1. The addition of chlorine to the drinking water supply has lessened the occurrence of typhoid, cholera, and dysentery 2. Chlorine byproducts are tentatively linked to several kinds of cancer ii. Fluoridation 1. Small amounts of fluoride have been added to most municipal drinking water since the mid 1940s to reduce tooth decay 2. As of 2002, 66% of U.S. public water supplies were fluoridated C. Municipal sewage treatment i. Wastewater, including sewage, usually undergoes several treatments at a sewage treatment plant to prevent environmental and public health problems; treated wastewater is then discharged into rivers, lakes, or the ocean 1. Primary treatment removes suspended and floating particles, such as sand and silt, by mechanical processes such as screening and gravitational settling a. The solid material that settles out is primary sludge b. The wastewater facilities for about 11% of the U.S. population have primary treatment only 2. Secondary treatment uses microorganisms to decompose the suspended organic material in wastewater a. Trickling filters degrade organic material in the water b. The activated sludge process produces secondary sludge c. Water that has undergone primary and secondary treatment is clear and free of organic wastes such as sewage d. The wastewater treatment facilities for about 62% of the U.S. population have both primary and secondary treatments 3. Tertiary treatments remove pollutants such as dissolved minerals, heavy metals, viruses, and organic compounds a. They purify wastewater for reuse in communities where water is scare

Chapter 21 b. The wastewater treatment facilities for about 27% of the U.S. population have primary, secondary, and tertiary treatments ii. Disposal of sludge 1. A major problem associated with wastewater treatment is disposal of the primary and secondary sludge 2. Five possible ways to handle the disposal of sludge are anaerobic digestion, application to soil as a fertilizer, incineration, ocean dumping, and disposal in a sanitary landfills D. Individual septic systems i. Require care to operate properly ii. If it is not maintained every two to five years, it can malfunction or overflow, releasing bacteria and nutrients into groundwater or waterways IV. Laws Controlling Water Pollution A. Using citizen watchdogs to monitor water pollution i. Provisions in both the Clean Water Act, the Safe Drinking Water Act, and other key environmental laws allow citizens to file suit when the government does not enforce the laws ii. Citizen action groups also pressure firms to clean up B. Safe Drinking Water Act (1974) i. Set uniform federal standards for drinking water to guarantee safe public water supplies throughout the U.S. ii. It requires the EPA to determine the maximum contaminant level for water pollutants iii. It was amended in 1986 and 1996; the 1996 version requires municipal water suppliers to tell consumers what contaminants are present that may pose a health risk to humans C. Clean Water Act (1977) i. Affects the quality of rivers, lakes, aquifers, estuaries, and coastal waters in the U.S. ii. It has two basic goals 1. To eliminate the discharge of pollutants in U.S. waterways 2. To attain water quality levels that make these waterways safe for fishing and swimming iii. The EPA is required to set up and monitor national emissions limitations under this act iv. In 1987 amendments to the Clean Water Act expanded the National Pollutant Discharge System to include nonpoint sources, such as sediment erosion from construction sites v. A 2000 EPA report found that 39% of the nation’s rivers, 45% of its lakes, and 51% of its estuaries were too polluted for swimming, fishing, or drinking D. Laws that protect groundwater i. Safe Drinking Water Act ii. The Resource, Conservation, and Recovery Act

Chapter 21

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

What Goes Into Your Local Storm Drains

Time: Materials: Handouts:

10 minutes prep; Full class period None (or local map) None

Procedures:

Explore the storm runoff drain system on your campus and the surrounding areas 1. Are they clearly marked? (If not, this might make a good class project) 2. Where do they lead?

3. Can you see evidence that any of the following materials are going down the storm drains? a. Animal waste b. Oil or grease c. Garbage d. Spills (what types) e. Other material (list) 4. What options are there for preventing these materials from getting to storm drains?

5. What options are there for removing these materials after they are found in storm drains?

Student See above Instructions: Specific Suggestions:

Consider doing this during a rainstorm.

Ask someone from a local water treatment facility to talk to your class Be sure to check around vacant lots, private homes and gas stations…but also be careful about trespassing and privacy issues!

Photographic record may be useful.

Objectives:

Explain sources and management opportunities for pollution in storm water runoff.

Chapter 21

Instructor Notes for In-Class Activity 2 Title:

Alternatives to “End of the Pipe” Wastewater Solutions

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: Industries can find much better solutions to wastewater problems if they have to meet emissions standards, but not required to use predetermined end-of-pipe solutions like primary and secondary treatment.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions:

Chapter 21

Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your classes are comfortable with it.

Objectives:

Explain end-of-pipe wastewater management, and alternative waste reduction options.

Chapter 21

Instructor Notes for In-Class Activity 3 Title:

Designing and Artificial Wetland

Time: Materials: Handouts:

5 minutes prep; 25 minutes in class None None

Procedures:

Divide students into small groups.

Have each design an artificial wetland to remove nitrogen, phosphorous and potassium from wastewater from a small suburban community.

Have them pay particular attention to: • How much water throughput they would expect • Whether it would be automatic or would require operators • How much of each of the pollutants they would expect to find, and how much could be removed in the system • Where they would locate the system (might be useful to think of a specific development in your area • Whether such a system could meet local, state and / or federal wastewater management regulations Have each group report its design to the class.

Discuss the similarities and differences.

Student See above Instructions: Specific Suggestions:

If possible, visit a local wetland, whether natural, reconstructed or artificial.

Objectives:

• •

Explain tertiary waste water treatment.

Describe how wetlands serve to reduce water pollution.

Chapter 21

Instructor Notes for In-Class Activity 4 Title:

Visit your local Waste Water Treatment Plant

Time: Materials: Handouts:

10 – 20 minutes prep; full class period None None

Procedures:

Most municipalities have a waste water treatment plant and they often give tours of their facility. They usually run about two –three hours. It is very informative and the students should walk away with a better appreciation of the water they use.

Student See above Instructions: Specific Suggestions:

Have the manager of the waste water treatment center come to your class and present on his facilities, before the visit. Then all the ground rules and the safety issues are addressed.

Objectives:

• •

Discuss the use of waste water treatment plants.

Describe the purpose of waste water treatment plants.

Chapter 21

Instructor Notes for In-Class Activity 5 Title:

What’s in your water?

Time: Materials: Handouts:

10 – 20 minutes prep; full class period pH strips, water plants None

Procedures:

Have individual students bring in a sample of water from a water source near their house, it may be a ocean, stream, lake, puddle or faucet (maybe before they bring in the sample, they can explain where they are getting it so that every student doesn’t bring in the same sample of city water).

Line up all the samples and test each sample for the pH factor, record the findings. Analyze the samples for pH and sediment.

Then put in a water plant in each sample of water and monitor the growth of the plant.

Student See above Instructions: Specific Suggestions:

If there is a microscope handy, it may be interesting to put a drop of water on a slide and see if there are any living organisms in the water.

Objectives:

• •

Discuss what is in the water we are living around.

List and briefly define eight categories of water pollutants.

Chapter 21

Instructor Notes for In-Class Activity 6 Title:

How much water do you need to live

Time: Materials: Handouts:

10 – 20 minutes prep; full class period None None

Procedures:

Have each student for a week, keep a log of all the water they have used or witnessed using. For example, watching parents do the laundry, how much water was used? Other uses of water would include, taking a shower, getting a drink of water, flushing the toilet, washing the car, washing the dishes, etc. After a week, they get together and see who has used the most water, who has used the least. Then they can discuss ways to cut their use of water.

Week two: have the students keep the same log, but use the changes they discussed to cut their water use. Were they successful in cutting their water use? How much water did they save as an individual and how much water did they save as a class? This will be a pretty impressive number.

Student See above Instructions: Specific Suggestions: Objectives:

• •

Describe the different areas where we use water.

Describe effective ways to save water.

Chapter 21

Answers to Critical Thinking and Review End of Chapter Questions: 1. What is sustainable water use?

Ans: While water is abundant, people need to understand and appreciate that it is limited in many regions, that there are environmental and economic costs of depleting or damaging water resources, and that unsustainable water use practices pose serious risks to people and ecosystems. The consumption of renewable natural resources is sustainable if it does not exceed the rate of long term renewal and does not impair the health and productivity of the ecosystems, communities or the economy. Sustainability is the fair and equitable access to water, water dependent resources, and related infrastructure.

2. What is water pollution? Why is wastewater treatment an important part of sustainable water use?

Ans: Water pollution consists of any physical or chemical change in water that adversely affects the health of humans and other organisms. Having water of good quality is just as important as having enough water. Water is used over and over-as for example, when a downstream town uses river water that an upstream city first used. Therefore, wastewater treatment is an important part of sustainable water use.

3. Describe the relationship between biochemical oxygen demand and dissolved oxygen available for fish.

Ans: Biochemical oxygen demand (BOD) is the amount of oxygen needed by microorganisms to decompose biological wastes into carbon dioxide, water, and minerals. A large amount of sewage or fertilizers generates a high BOD, which lowers the level of dissolved oxygen in the water. Less dissolved oxygen means less oxygen available to fish and can cause them to die.

4. Distinguish between oligotrophic and eutrophic lakes.

Ans: An oligotrophic lake has clear water and supports small populations of aquatic organisms.

Eutrophication is the enrichment of a lake, estuary, or slow-flowing stream by inorganic plant and algal nutrients such as phosphorus; an enriched body of water is said to be eutrophic.

5. How do midwestern farmers threaten the livelihood of fishermen in the Gulf of Mexico?

Ans: Every spring and summer, fertilizer runoff from midwestern fields and manure runoff from livestock operations find their way into the Mississippi River and, from there, into the Gulf of Mexico. The amount of such runoff is considerable. These nutrients (nitrogen and phosphorus) are largely responsible for a huge dead zone in the Gulf of Mexico. The dead zone extends from the sea floor up into the water column, sometimes to within a few meters of the surface. Other than bacteria that thrive in oxygen-free environments, no life exists in the dead zone. The water does not contain enough dissolved oxygen to support fishes or other aquatic organisms. Fishes,

Chapter 21 shrimp, and other active swimmers avoid the area, but bottom dwellers such as sea stars, brittle stars, worms, and clams suffocate and die.

6. Does agriculture water pollution come from point sources or nonpoint sources? What about municipal waste? Industrial waste?

Ans: Nonpoint source pollution is much more difficult and expensive to control than point source pollution. U.S. environmental policies have not effectively addressed many nonpoint sources of pollution, which requires regulating land use, agricultural practices, and many other activities. Such regulation necessitates the interaction and cooperation of many government agencies, environmental organizations, and private citizens, which can be enormously challenging. Agriculture water pollution is normally classified as a nonpoint source of water pollution. Sewage is the main pollutant produced by cities and towns, but municipal water pollution also has a nonpoint source: urban runoff from storm sewers. Urban runoff carries salt from roadways, untreated garbage, animal wastes, construction sediments, and traffic emissions. It often may contain such contaminants as asbestos, chlorides, copper, cyanides, grease, hydrocarbons, lead, motor oil, organic wastes, phosphates, sulfuric acid, and zinc.

Industries generate different types of water pollutants and is classified as a source pollutant since the origin of the pollutant can normally be determined. Food-processing industries produce organic wastes that are readily decomposed but have a high BOD. In addition to a high BOD, pulp and paper mills produce toxic compounds and sludge. Many organic compounds, such as pesticides, pharmaceuticals, solvents, and industrial chemicals, are quite toxic to organisms.

Thermal pollution occurs when heated water, produced during many industrial processes, is released into waterways.

7. Contrast organic compounds and inorganic chemicals as types of water pollution.

Ans: Organic compounds are chemicals that contain carbon atoms; a few examples of natural organic compounds are sugars, amino acids, and oils. Most of the thousands of organic compounds found in water are human-produced chemicals; these synthetic chemicals include pesticides, solvents, industrial chemicals, and plastics. Inorganic chemicals are contaminants that contain elements other than carbon; examples include acids, salts, and heavy metals.

Inorganic chemicals do not easily degrade, or break down. When they are introduced into a body of water, they remain there for a long time.

8. Tell whether each of the following represents point source pollution or nonpoint source pollution: fertilizer runoff from farms, thermal pollution from a power plant, urban runoff, sewage from a ship, erosion sediments from deforestation.

Ans: Point Source Pollution: thermal pollution from a power plant, sewage from a ship Nonpoint Source Pollution: fertilizer runoff from farms, urban runoff, erosion sediments from deforestation.

9. What is the source of arsenic contamination of groundwater in Bangladesh?

Chapter 21 Ans: The groundwater in Bangladesh wells is contaminated with high levels of naturally occurring arsenic.

10. Why is chlorine added to drinking water? Why does the Environmental Protection Agency recommend that public water treatment facilities find alternatives to chlorine?

Ans: Most municipal water supplies are treated before being used so that the water is safe to drink. Water is usually treated with aluminum sulfate to cause suspended particles to clump and settle out, filtered through sand, and disinfected by adding chlorine. Because there is concern over whether low levels of chlorine in drinking water pose a health hazard, the EPA has proposed that water treatment facilities reduce the maximum permissible level of chlorine in drinking water and look for alternatives to chlorine disinfection.

11. What is removed during each of the three stages of wastewater treatment: primary, secondary, and tertiary?

Ans: Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants from wastewater and household sewage, both runoff and domestic. It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants.

• Primary treatment consists of temporarily holding the sewage in a basin where heavy solids can settle to the bottom while oil, grease and lighter solids float to the surface. The settled and floating materials are removed and the remaining liquid is subjected to secondary treatment.

• Secondary treatment removes dissolved and suspended biological matter.

• Tertiary treatment is sometimes defined as anything more than primary and secondary treatment in order to allow rejection into a highly sensitive or fragile ecosystem. Treated water is sometimes disinfected chemically or physically prior to discharge into an aquatic ecosystem it can be used for the irrigation of a golf course, green way or park.

12. What is sludge? How is it disposed of?

Ans: Primary and secondary sludge consist of the solids remaining after sewage treatment has been completed. Primary sludge is formed during primary treatment, and secondary sludge is formed during secondary treatment. One of the most pressing problems of wastewater treatment is sludge disposal. Five possible ways to handle sludge are anaerobic digestion, application to soil as a fertilizer, incineration, ocean dumping, and disposal in a sanitary landfill.

13. Taking a systems perspective, suggest how to prevent BOD from animal sewage and milk processing of a dairy farm from reaching an adjacent river.

Ans: Answers will vary.

14. In what ways might climate change make dead zones in the ocean worse? Better?

Ans: Less oxygen dissolves in warm water than in cool water, and the amount of oxygen dissolved in water has important effects on aquatic life. As oceans warm dead zones could become larger. In contrast, scientists think that Hurricane Dolly in 2008 may have reduced the

Chapter 21 dead zone by churning the water. Climate scientists expect hurricanes to get stronger, which could mean more churning and thus smaller dead zones.

The spill happened at station C you would expect to find the most dead fish at station E. 15. Is industrial waste discharge to a river regulated under the Clean Water Act or the Safe Drinking Water Act? Ans: Industrial waste discharge into a river is regulated by the Clean Water Act. The Clean Water Act has two basic goals: eliminate the discharge of pollutants in U.S waterways and to attain water quality levels that make these waterways safe for fishing and swimming.

16. The graph reflects the monitoring of dissolved oxygen concentrations at six stations along a river. The stations are located 20 m apart, with A the farthest upstream and F the farthest downstream. Where along the river did a sewage spill occur? At which station would you most likely discover dead fish?

INSERT GRAPH PAGE 461 Ans: The spill happened at station C you would expect to find the most dead fish at station E.

Answers to Review Questions Types of Water Pollution 1. What are the eight main groups of water pollutants? Give an example of each main type.

Water pollution consists of any physical or chemical change in water that adversely affects the health of humans and other organisms. Water pollutants are divided into eight categories: sewage, disease-causing agents, sediment pollution, inorganic plant and algal nutrients, organic compounds, inorganic chemicals, radioactive substances, and thermal pollution. Sewage is the release of wastewater from drains or sewers (such as from toilets, washing machines, and showers); it includes human wastes, soaps, and detergents.

Sewage is also responsible for the transmission of another group of water pollutants, disease-causing agents. Examples of disease-causing agents include bacteria, viruses, protozoa, and parasitic worms. Sediment pollution, primarily from soil erosion, increases water turbidity, thereby reducing photosynthetic productivity in the water. Inorganic plant and algal nutrients, such as nitrogen and phosphorous, contribute to enrichment, the fertilization of a body of water. Many organic compounds, such as pesticides, pharmaceuticals, solvents, and industrial chemicals, are quite toxic to organisms.

Likewise, inorganic chemicals include toxins such as lead and mercury. Radioactive substances include the wastes from mining, refining, and using radioactive metals.

Lastly, thermal pollution occurs when heated water, produced during many industrial processes, is released into waterways.

Chapter 21 2. What is biochemical oxygen demand (BOD)? How is BOD related to sewage?

Biochemical oxygen demand (BOD) is the amount of oxygen needed by microorganisms to decompose biological wastes into carbon dioxide, water, and minerals. A large amount of sewage generates a high BOD, which lowers the level of dissolved oxygen in the water.

3. What causes the dead zone in the Gulf of Mexico?

A dead zone is a section of the ocean or a sea in which oxygen has been depleted to the point that most animals and bacteria cannot survive; it is often caused by runoff of chemical fertilizers or plant and animal wastes.

Water Quality Today 1. How do point source and nonpoint source pollution differ?

Point source pollution is water pollution that can be traced to a specific spot. Nonpoint source pollution consists of pollutants that enter bodies of water over large areas rather than being concentrated at a single point of entry.

2. What are some major agricultural, industrial, and municipal water pollutants?

Agriculture is the biggest contributor to surface-water pollution. Water pollutants associated with agriculture include fertilizers, pesticides, plant and animal wastes, and eroded soil. Water pollutants associated with municipal waste can include surface runoff containing a variety of chemical and organic contaminants, as well as sewage. Lastly, water pollutants associated with industrial wastes vary based on the type of industry and can include a variety of chemicals, organic materials, and radioactive materials.

Improving Water Quality 1. How is most drinking water purified in the United States?

Most municipal water supplies are treated before being used so that the water is safe to drink. Water is usually treated with aluminum sulfate to cause suspended particles to clump and settle out, filtered through sand, and disinfected by adding chlorine.

2. Why is chlorine added to drinking water? What is the potential problem with adding chlorine to drinking water?

Chlorine is added to drinking water for disinfection purposes. There is a concern that chlorine in drinking water creates health hazards, so alternatives, including UV radiation and ozonation, are being developed.

Chapter 21

3. Distinguish among primary sewage treatment, secondary sewage treatment, tertiary sewage treatment, and septic tanks.

Primary sewage treatment treats wastewater by removing suspended and floating particles using mechanical processes. Secondary sewage treatment treats wastewater biologically to decompose suspended organic material; it reduces the water’s biochemical oxygen demand. Tertiary sewage treatment is the advanced wastewater treatment method that is sometimes employed after primary and secondary treatments are completed; its aim is to eliminate synthetic organic compounds in the water. Tertiary treatments include a variety of biological, chemical, and physical processes, and help reduce phosphorus and nitrogen in the water. Septic tanks work much like primary treatment in municipal sewage treatment. Within a septic system, sewage from a house is piped to the septic tank, where particles settle to the bottom.

Laws Controlling Water Pollution 1. What are the main goals of the Safe Drinking Water Act? The Clean Water Act? The main goals of the Safe Drinking Water Act are to set uniform federal standards for drinking water to guarantee safe public water supplies throughout the United States.

Likewise, the Clean Water Act has two basic goals: to eliminate the discharge of pollutants into U.S. waterways and to attain water quality levels that make these waterways safe to fish and swim in.

2. How do maximum containment levels and national emission limitations differ?

The maximum containment level is the upper limit for the concentration of a particular pollutant in water intended for human consumption. The Environmental Protection Agency (EPA) determines maximum containment levels for water pollutants that might affect human health and mandated by the Safe Drinking Water Act. The National emission limitation is the maximum permissible amount of a water pollutant that can be charged from a sewage treatment plant, factory, or other point source. The Clean Water Act instructs the EPA to set up and monitor national emission limitations.

Chapter 22 Pest Management Lecture Outline: I. What is a Pesticide?

A. Narrow-spectrum pesticides kill only the organism for which it was intended and do not harm any other species B. Most pesticides are broad-spectrum pesticides, do not degrade readily and/or break down into compounds as dangerous as or more dangerous than the original pesticide C. First-generation and second-generation pesticides i. Pre 1940s, pesticides were either inorganic (contained lead, mercury, and arsenic) or organic compounds(botanicals and synthetic botanicals) ii. First-generation pesticides represent both inorganic and botanical pesticides iii. Second-generation pesticides represent the vast arrays of poisons in use today D. The major groups of insecticides i. Usually classified into groups based on chemical structure 1. Chlorinated hydrocarbons were widely used from the1940s until the 1960s when most were banned a. Examples include DDT, endosulfan, lidane, and methoxychlor b. Synthetic, broad-spectrum insecticides c. Slow to degrade d. Persist in the environment and in organisms 2. Organophosphates contain phosphorus and have generally replaced chlorinated hydrocarbons in large-scale agricultural use a. Examples include methamidophos, dimethoate, and malathion b. More poisonous than other types of insecticides c. Highly toxic to terrestrial and aquatic organisms d. They do not persist in the environment for as long as chlorinated hydrocarbons 3. Carbamates are derived from carbamic acid a. Examples include carbaryl and aldicarb b. Broad-spectrum insecticides c. Generally not as toxic to mammals E. The major kinds of herbicides i. Herbicides kill or inhibit the growth of unwanted vegetation ii. They tend to be grouped according to how they act and what they kill 1. Selective herbicides kill only certain types of plants a. Broad-leaf herbicides kill plants with broad leaves but do not kill grasses b. Grass herbicides kill grasses but are safe for most other plants 2. Nonselective herbicides kill all vegetation II. Benefits and Problems with Pesticides A. Benefit: disease control B. Benefit: crop protection

Chapter 22 i. Pests eat or destroy more than one-third of the world’s crops ii. Pesticides reduce the amount of a crop lost through competition with weeds, consumption by insects, and diseases caused by plant pathogens iii. Monocultures are one reason why agricultural pests are found in such great numbers in fields C. Problem: evolution of genetic resistance i. The prolonged used of a particular pesticide can cause a pest population to evolve genetic resistance ii. At least 84 weed species are currently resistant to certain herbicides iii. The pesticide treadmill refers to the predicament in which the cost of applying pesticides increases (because they have to be applied more frequently or in larger doses) while their effectiveness decreases (as a result of increasing genetic resistance in the target pests) iv. Resistance management encompasses strategies for managing genetic resistance in order to maximize the period in which a pesticide is useful D. Problem: imbalances in the ecosystem i. Beneficial insects are killed as effectively as pest insects ii. Pesticides are indirectly responsible for a large reduction in the populations of natural enemies 1. They indirectly kill natural enemies due to large scale consumption of the pesticide when consuming the pests 2. Creation of new pests becomes possible because the pesticide kills most of a certain pest’s natural predators, parasites, and competitors E. Problems: persistence, bioaccumulation, and biological magnification i. Some pesticides are extremely persistent in the environment and may take many years to break down into less toxic forms 1. Persistent pesticides are stored in the fatty tissues of animals who ingest them 2. Bioaccumulation is the buildup of a persistent pesticide or other toxic substance in an organism’s body 3. The increase in pesticide concentrations as the pesticide passes through successive levels of the food web is known as biological magnification F. Problem: mobility in the environment i. Pesticides do not stay where they are applied but tend to move through the soil, water, and air ii. Pesticide mobility is a problem for both wildlife and humans 1. It can be lethal to aquatic organisms (i.e., fish), and/or cause bone degeneration, decrease their competiveness and increase their chances of being preyed upon 2. 14.1 million U.S. residents drink water containing traces of five widely used herbicides 3. Herbicides can elevate cancer risk in humans III. Risks of Pesticides to Human Health A. Exposure to pesticides is greater than most people realize and often occurs without their knowledge

Chapter 22 i. Short-term effect of exposure 1. Short-term exposure can harm organs and even cause death 2. A person with a mild case of pesticide poisoning may exhibit symptoms such as nausea, vomiting, and headaches a. Pesticides poison approximately 67,000 Americans each year b. Globally, 3 million people are poisoned by pesticides, 220,000 die 3. Almost any pesticide can kill a human if the dose is large enough ii. Long-term effects of pesticides 1. Long-term exposure can cause cancer 2. Exposure to even trace amounts can disrupt the human endocrine system 3. An association between various cancers and long-term exposure to low levels of pesticides has been shown in many studies 4. Other health concerns such as sterility, birth defects, miscarriages in pregnant women have been linked to long-term pesticide exposure IV. Alternatives to Pesticides A. Alternative ways to control pests include cultivation methods, biological controls, pheromones and hormones, reproductive controls, genetic controls, quarantine, and irradiation B. Integrated pest management (IPM), which combines various alternative methods of pest control, is the most effective way to control pests C. Using cultivation methods to control pests i. Using an insect vacuum, interplanting mixtures of plants, and strip cutting are effective cultivation methods used to control pests ii. The proper timing of planting, fertilizing, and irrigating promote healthy, vigorous plants that are more resistant to pests, because they are not stressed by other environmental factors D. Biological controls i. A method of pest control that involves the use of naturally occurring disease organisms, parasites or predators to control pests is referred to as a biological control 1. More than 300 species have been introduced as biological control agents to North America 2. Finding an effective parasite or predator is difficult ii. The pest species typically does not evolve genetic resistance to the biological control agent the same way it does to pesticides iii. Nematodes and fungi as biological control agents 1. Nematodes are effective against mosquitoes, corn borers, weevils, grasshoppers, and locusts 2. Fungal spores can target desert locusts iv. Problems with biological control 1. Attack of an unintended host 2. Make sure it does not become a pest itself E. Pheromones and hormones i. Pheromones can be used to control individual pest species

Chapter 22 ii. Synthetic hormones have been used to trigger abnormal molting in insect larvae F. Reproductive controls i. Reproductive control strategies suppress pests by sterilizing some of its members ii. The sterile male technique helps to control the reproductive potential of the pest population so that the population of the next generation is much smaller G. Genetic controls i. Many varieties of crops have been selectively breed to be genetically resistant to disease organisms or insects 1. Through traditional selective breeding techniques this can take as long as 10-20 years 2. Plant breeders are in a continual race to keep one step ahead of plant pathogens ii. Genetic engineering can produce genetically modified (GM) plants that are pest-resistant in fewer generations H. Quarantine i. Governments attempt to prevent the importation of foreign pests and diseases by practicing quarantine ii. It is an effective, though not foolproof, means of control I. The systems approach: integrated pest management (IPM) i. IPM is a combination of control methods is often more effective than controlling pests with a single technique 1. IPM combines a variety of biological, cultivation, and pesticide controls tailored to the conditions and crops of an individual farm, campus, city, or greenhouse 2. IPM requires a thorough knowledge of the system, including life cycles, feeding habits, travel, and nesting habits of the pests as well as their interactions with their hosts and other organisms ii. IPM is the management rather than the eradication of pests; it requires that farmers be educated J. Irradiating foods i. Food irradiation or cold pasteurization prevents insects and other pests from damaging harvested food by exposing it to ionizing radiation ii. Irradiation lessens the need for pesticides and food additives V. Laws Concerning Pesticide Use A. Food, Drug, and Cosmetics Act (FDCA – 1938) i. Pesticide Chemicals Amendment (1954), aka the Miller Amendment, requires the establishment of acceptable and unacceptable levels of pesticides in food ii. The Delaney Clause (1958) states that no substance capable of causing cancer in test animals or in humans would be permitted in processed food B. The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA – 1947) i. Regulates the effectiveness of pesticides ii. A 1988 amendment required reregistration of older pesticides and subjected them to the same toxicity tests that new pesticides face C. Food Quality Protection Act (1996)

Chapter 22 i. This Act amended both the FDCA and FIFRA ii. It requires that the increased susceptibility of infants and children to pesticides be considered when establishing pesticide residue limits for some 9,700 pesticide uses on specific crops iii. It also reduces the time it takes to ban a pesticide considered dangerous from 10 years to 14 months VI. The Manufacture and Use of Banned Pesticides A. Some U.S. companies manufacture pesticides that are banned or heavily restricted in the U. S. and export them to developing countries for use B. The U.N. Food and Agriculture Organization (FAO) is attempting to help developing nations become more aware of dangerous pesticides C. The importation of food tainted with banned pesticides i. Some of the food imported into the U.S. contains traces of banned pesticides such as DDT, dieldrin, chlordane, and heptachlor ii. The FDA inspect only about 1% of the food shipments that enter the U.S. each year D. The global ban of persistent organic pollutants i. The Stockholm Convention on Persistent Organic Pollutants (2004) seeks to protect human health and the environment from the 12 most toxic chemicals (persistent organic pollutants) ii. It only applies to countries that have ratified the treaty

Chapter 22

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Pesticide Use on Campus or in your Area

Time: Materials: Handouts:

0 minutes prep; 15 - 25 minutes in class Internet access, campus map None

Procedures:

Have students catalog pesticides being used on campus or around your town, including how well those pesticides are being managed.

Options: go on the internet to find “Material Safety Data Sheets” (MSDS’s) for some of these substances.

Use their explorations as a source of discussion • How much pesticide use did you encounter?

• What types of pests are being managed? o Mosquitoes? o Agricultural pests? o Rodents, ants and roaches? o Pests on decorative plants? o Other (list) • Do you think your campus uses more or less pesticide than most?

• What, if any, alternatives are there to these pesticides?

Student Working in groups as assigned by your instructor, Explore how Instructions: pesticides are being used on campus or around town. You can get some of your information by touring, and other information by contacting grounds crew or facility managers.

1. How well do you understand the potential effects of these substances 2. How much pesticide use did you encounter?

3. Do you think your campus uses more or less pesticide than most?

4. What, if any, alternatives are there to these pesticides?

5. How are unused or unneeded pesticides disposed of?

Specific Suggestions:

Invite someone from campus grounds or from local pest management agency to come to your class.

Objectives:

• •

Describe local pest management needs and practices.

Explain how pesticides are used on campus and in urban, suburban or rural areas?

Chapter 22

Instructor Notes for In-Class Activity 2 Title:

Different Pesticide Qualities for Different Applications

Time: Materials: Handouts:

5 minutes prep; 15 – 25 minutes in class None None

Procedures:

Pesticides have four highly sought after qualities: 1. Highly specific (especially not harming humans) 2. Highly effective (kills all of target species) 3. Breaks down rapidly into non-toxic daughter compounds 4. Inexpensive to produce and apply However, it is rarely possible to achieve all of these qualities in a single pesticide.

Divide students into groups, and have them decide which of these characteristics is most important in the following settings, and why.

Then discuss as a class.

1. Eliminating mosquitoes that carry malaria, West Nile Virus, and other infectious diseases 2. Killing household pests such as cockroaches, fleas and mice 3. Eliminating rust from large North American corn fields 4. Removing unattractive moth nests from trees lining streets in resort towns 5. Killing fungi while drying herbs for mass markets 6. Eliminating nuisance pigeons from public and residential areas

Student See above Instructions: Specific Suggestions:

None

Objectives:

Describe the advantages and disadvantages of pesticide use.

Chapter 22

Instructor Notes for In-Class Activity 3 Title:

Lifting the Ban on DDT

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: DDT saves lives from malaria, and the US ban on production and use of DDT should be lifted.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Student See above Instructions: Specific

The instructor is likely to have to serve as a facilitator or moderator from

Chapter 22 Suggestions:

time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Describe the advantages and disadvantages of pesticide use.

Chapter 22

Instructor Notes for In-Class Activity 4 Title:

Designing an Integrated Pest Management Plan

Time: Materials: Handouts:

0 Minutes prep; 15 – 20 minutes in class None None

Procedures:

Divide students into groups of 3 – 4. Have them develop an Integrated Pest Management (IPM) plan for controlling mice in a grain warehouse.

Have them list at least 10 non-chemical methods for eliminating mice.

Use their findings as a springboard to discuss IPM in agricultural settings. Which of their methods would be relatively easy, and which more difficult?

Student See above Instructions: Specific Suggestions:

None

Objectives:

Explain Integrated Pest Management (IPM) and provide examples of IPM methods.

Chapter 22

Instructor Notes for In-Class Activity 5 Title:

History of Pesticides

Time: Materials: Handouts:

10 – 20 minutes prep; full class period None None

Procedures:

Have students go out and interview individuals over 50 (grandparents, neighbors etc) on what they think of pesticides? Were they exposed to pesticides? Do they have any reaction to pesticides? Do they use pesticides? What do they remember about the early days of pesticides?

Report back to the class on your interview.

Student See above Instructions: Specific Suggestions: Objectives:

• •

Discuss trends in early use of pesticides.

Compare and contrast the different uses of pesticides used today compared to the use of pesticides of the 1960’s.

Chapter 22

Instructor Notes for In-Class Activity 6 Title:

Alternative Pesticides

Time: Materials: Handouts:

10 – 20 minutes prep; full class period Internet None

Procedures:

As a class or in groups, research the different alternative types of pesticides. Assign each group a different alternative pesticide and have them research the pesticide and report back to the class. Which alternative pesticide would work best in your area? Which one would not work at all? Is there a danger using the different alternative pesticides?

Student See above Instructions: Specific Suggestions: Objectives:

Describe alternative ways to control pests, including cultivation methods, biological controls, pheromones and hormones, reproductive controls, genetic controls, quarantine, integrated pest management, and irradiating foods.

Chapter 22

Answers to Critical Thinking and Review End of Chapter Questions: 1. Distinguish among insecticides, herbicides, fungicides, and rodenticides.

Ans: Pesticides are toxic chemicals used to kill pests such as insects (insecticides), weeds (herbicides), fungi (fungicides), and rodents (rodenticides).

2. Describe the general characteristics of each of the following groups of insecticides: chlorinated hydrocarbons, organophosphates, and carbamates.

Ans: Chlorinated hydrocarbons are an organic compound containing chlorine. Generally speaking, chlorinated hydrocarbons are broad-spectrum insecticides. Most are slow to degrade and persist in the environment for many months or even years. Organophosphates are organic compounds that contain phosphorus. Organophosphates are more poisonous than other types of insecticides, and many are highly toxic to birds, bees, and aquatic organisms. The toxicity of many organophosphates in mammals, including humans, is comparable to that of some of our most dangerous poisons-arsenic, strychnine, and cyanide. Organophosphates do not persist in the environment as long as chlorinated hydrocarbons do. Carbamates, the third group of insecticides, are broad-spectrum insecticides derived from carbamic acid. Carbamates are generally not as toxic to mammals as the organophosphates, although they still show broad, nontarget toxicity.

3. Overall, do you think the benefits of pesticide use outweigh its disadvantages? Give at least two reasons for your answer.

Ans: Answers will vary.

4. Sometimes pesticide use increases the damage done by pests. Explain.

Ans: Beneficial insects are killed as effectively as pest insects. In a study of the effects of spraying the insecticide dieldrin to kill Japanese beetles, scientists found a large number of dead animals in the treated area, such as birds, rabbits, ground squirrels, cats, and beneficial insects.

Because the natural enemies of pests often starve or migrate in search of food after pesticide is sprayed in an area, pesticides are indirectly responsible for a large reduction in the populations of these natural enemies. Pesticides also kill natural enemies directly because predators consume a lot of the pesticide when consuming the pests. After a brief period, the pest population rebounds and gets larger than ever, partly because no natural predators are left to keep its numbers in check.

5. The widely used herbicide Roundup is starting to lose its effectiveness in killing certain weeds. Explain why.

Ans: The prolonged use of a particular pesticide can cause a pest population to develop genetic resistance to the pesticide. Insects are not the only pests to evolve genetic resistance; at least 84 weed species are currently resistant to certain herbicides. Some weeds, such as annual ryegrass and canary grass, are resistant to all available herbicides.

Chapter 22

6. How is the buildup of insect resistance to insecticides similar to the increase in bacterial resistance to antibiotics?

Ans: Manufacturers of chemical pesticides have often responded to genetic resistance by recommending that the pesticide be applied more frequently or in larger doses. Alternatively, they recommend switching to a new, often more expensive, pesticides. The same occurs with antibiotic resistance, as antibiotics become ineffective at controlling bacteria stronger and often more toxic antibiotics must be used.

7. How does genetic change in response to biological control agents differ from genetic resistance to pesticides?

Ans: The pest species typically does not evolve genetic resistance to the biological control agent in the same way it does to a pesticides, since both pest and predator are living organisms that are responsive to natural selection. As the pest evolves a way to resist the biological control agent, the agent in turn may evolve some sort of countermeasure against the pest.

8. Biological control is often much more successful on a small island than on a continent. Offer at least one reason why this might be the case.

Ans: Care must be taken to ensure that the introduced control agent does not attack unintended hosts and become a pest itself. On an island there may be fewer opportunities for the control to become a pest or it may be prevented from spreading off the island.

9. It is more effective to use the sterile male technique when an insect population is small than when it is large. Explain.

Ans: One disadvantage of the sterile male technique is that to be effective it must be carried out continually. Therefore, it would most likely be more effective to use the steril male technique when an insect population is small. Moreover, if the sterilization technique is discontinued, the pest population rebounds to a high level in a few generations. The number of potentially normal males will increase with increases in population size, therefore, more sterile males will need to be released.

10. Define integrated pest management (IPM). List five tools of IPM, and give an example of each.

Ans: Integrated pest management (IPM) is a systems approach that combines several pest control methods that, if used in the proper order and at the proper times, keep the size of a pest population low enough that it does not cause substantial economic loss. The five tools of IPM are; Cultivation practices, such as growing molasses grass with corn. The molasses grass releases chemicals that repel some corn pests. Resistant crop varieties for example, genetically modified Bt corn resistant to some pests. Natural enemies and the habitat they need, for example, hedges, trees and other appropriate plants provide a place for natural predators to live when not feeding

Chapter 22 on pests. Pheromone traps containing female pest pheromones attract and capture the males.

Judicious use of pesticides, farm workers sometimes selectively spray pesticides.

11. How is IPM related to ecological concepts such as food webs and energy flow?

Ans: IPM takes into account all the trophic levels in a food web, from primary producer to consumers. Pesticides often kill the beneficial consumers along with the target pest species. This disrupts the balance of the food web. IPM also recognizes that energy decreases as it moves up trophic levels therefore the number of beneficial insects will be less than the number of pests.

12. Which of the following uses of pesticides do you think are most important? Which are least important? Explain your views. a. keeping roadsides free of weeds b. controlling malaria c. controlling crop damage d. producing blemish-free fruits and vegetables Ans: Answers will vary.

13. Why is pesticide misuse increasingly viewed as a global environmental problem?

Ans: The WHO estimates that, globally, pesticides poison more than 3 million people each year; of these, about 220,000 die. The incidence of pesticide poisoning is highest in developing countries, in part because they often use dangerous pesticides that are banned or greatly restricted by highly developed nations. Pesticide users in developing nations often are not trained in the safe handling and storage of pesticides, and safety regulations are generally more lax there.

14. Propose an integrated pest management plan to control rabbits in a garden. Your approach may include a rodenticide.

Ans: Answers will vary.

15. Climate change may lead to a greater need for pesticides to control mosquitoes. Suggest some ways in which other pesticide uses could increase or decrease as the Earth warms and precipitation patters shift over the next century.

Ans: Answers will vary 16. Do you think this cartoon reasonably depicts the challenge of reducing pesticide use?

INSERT IMAGE FROM THIS QUESTION PAGE 480 Ans: Answers will vary.

Answers to Review Questions What Is a Pesticide?

Chapter 22 1. How do narrow-spectrum pesticides differ from broad-spectrum pesticides?

Narrow-spectrum pesticides kill only the target organism. Broad-spectrum pesticides kill a variety of organisms, including beneficial organisms, in addition to target pests.

Benefits and Problems with Pesticides 1. What are two important benefits of pesticide use?

Pesticides help prevent malaria and the transmission of other diseases by insects. They also help reduce crop losses from pests, thereby increasing overall agricultural productivity. In addition, pesticides can reduce competition with weeds, crop consumption by insects, and diseases caused by plant pathogens such as certain fungi and bacteria.

2. Why are monocultures susceptible to pest problems?

A monoculture is the cultivation of only one type of plant over a large area. It represents a system that is out of balance compared to what would be found without human intervention (i.e., in nature). Because agricultural fields are monocultures that provide abundant food for pest organisms, and many natural predators are usually absent from monocultures, these fields provide an abundant and safe food source for pest organisms.

3. What are persistence, bioaccumulation, and biological magnification?

A pesticide that demonstrates persistence takes a long time to break down into less toxic forms. Bioaccumulation is the buildup of a persistent pesticide or other toxic substance in an organism’s body. Lastly, biological magnification is the increased concentration of toxic chemicals, such as certain pesticides, in the tissues of organisms at higher trophic levels in food webs.

4. What is the pesticide treadmill?

The pesticide treadmill is a predicament faced by pesticide users, in which the cost of applying pesticides increases (because they have to be applied more frequently or in larger doses) while their effectiveness decreases (as a result of increasing genetic resistance in the target pest).

Risks of Pesticides to Human Health 1. What are some of the long-term effects of pesticides on human health?

Chapter 22 Long-term effects of pesticides include the threat of cancer (i.e., lymphoma, leukemia, etc.), interference with the actions of natural hormones within the human body (i.e., sterility), and increased risk of Parkinson’s disease.

2. Why are endocrine disrupting pesticides of particular concern?

Endocrine disruption occurs when a chemical interferes with or mimics a hormone associated with growth and development in humans or other animals. Endocrine disrupters include pesticides such as atrazine and DDT. Problems associated with endocrine disrupters include abnormal physical features – such as deformed reproductive organs – and aberrant behavior.

Alternatives to Pesticides 1. What is an example of using cultivation methods to control pests? Of using pheromones and hormones?

When attempting to control pests, many alternatives to pesticide use exist. For example, cultivation methods can adversely affect or discourage pests from causing damage to crops. Such pest controlling techniques include strip cutting, intercropping, and crop rotation. Likewise, the use of pheromones and hormones are also effective in pest control. A pheromone is a natural substance produced by animals to stimulate a response in other members of the same species; pheromones can be used to lure insects to traps or to confuse insects so that they cannot locate mates. Insect hormones are natural substances produced by insects to regulate their own growth and metamorphosis; a hormone present at the wrong time in an insect’s life cycle disrupts its normal development.

2. What is integrated pest management? Why is IPM considered a systems approach?

Integrated pest management (IPM) is a combination of pest control methods that, if used in the proper order and at the proper times, keep the size of a pest population low enough that it does not cause substantial economic loss. It is considered a systems approach because to be effective, IPM requires a thorough knowledge of the system, including life cycles, feeding habits, travel, and nesting habits of the pests as well as all their interactions with their hosts and other organisms.

Laws Controlling Pesticide Use 1. What three laws regulate pesticides in the United States? What are the goals of each law?

Three laws help regulate pesticides in the United States. They include the Food, Drug, and Cosmetics Act, the Federal Insecticide, Fungicide, and Rodenticide Act, and the Food Quality Protection Act. The Food, Drug, and Cosmetics Act (FDCA), as originally passed, recognized the need to regulate pesticides in food but did not provide a means of

Chapter 22 regulation. The Miller Amendment required the establishment of acceptable and unacceptable levels of pesticides in food, and the Delany Clause stated that no substance capable of causing cancer in laboratory animals or in humans would be permitted in processed food. The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) was amended over the years to require testing and registration of the active ingredients of pesticides; the 1998 version required the re-registration of older pesticides, which subjected them to the same toxicity tests that new pesticides face. The Food Quality Protection Act amended both the FDCA and FIFRA and revised the Delaney Clause by establishing identical pesticide residue limits – those that pose a negligible risk – for both raw and processed foods.

The Manufacture and Use of Banned Pesticide 1. What is the Stockholm Convention on Persistent Organic Pollutants?

The Stockholm Convention on Persistent Organic Pollutants seeks to protect human health and the environment from the 12 most toxic chemicals on Earth. These chemicals happen to be persistent organic pollutants (POPs). They are a group of persistent, toxic chemicals that bioaccumulate in organisms and can travel thousands of kilometers through air and water to contaminate sites far removed from their source.

Chapter 23 Solid and Hazardous Wastes Lecture Outline: I. Solid Waste a. The U.S. generates more solid waste, per capita, than any other country (2.1 kg per person per day) b. Waste generation is an unavoidable consequence of prosperous, high-technology industrial economies c. Types of solid waste i. Municipal solid waste is a heterogeneous mixture compose primarily of paper and paperboard, yard waste, plastics, food waste, metals, rubber, leather, textiles, wood, and glass ii. Municipal solid waste is discarded by homes, office buildings, retail stores, restaurants, schools, hospitals, and other commercial and institutional facilities iii. Nonmunicipal solid waste is generated by industry, agriculture, and mining d. Disposal of solid waste i. Dump it and/or bury it 1. Open dumps 2. Sanitary landfills a. Open dumps have been replaced by sanitary landfills b. They receive about 54% of the solid waste generated in the U.S. c. They use sophisticated systems to collect leachate 3. Problems associated with sanitary landfills a. Production of methane gas b. Contamination of surface water and groundwater by leachate c. Closing a full sanitary landfill involves considerable expense d. The special problem of plastic i. Most plastics are chemically stable and do not readily break down, or decompose ii. Special plastics have the ability to degrade or disintegrate (i.e., photodegradable and biodegradable plastics) e. The special problem of tires i. Made of vulcanized rubber which cannot be melted and reused ii. They are a fire hazard and provide breeding habitats for mosquitoes ii. Burn it (incineration) 1. Incineration reduces the volume of solid waste by up to 90% 2. Incineration produces heat that can make steam to warm buildings and generate electricity

Chapter 23 3. Types of incinerators a. Mass burn incinerators are large and are designed to recover the energy produced from combustion b. Modular incinerators are smaller and burn all solid waste c. Refuse-derived fuel incinerators burn only the combustible portion of solid waste 4. Problems associated with incineration a. Air pollution i. Incinerators can pollute the air with carbon monoxide, particulates, heavy metals, and other hazardous materials ii. Lime scrubbers and electrostatic precipitators can be installed as pollution control devices b. Large quantities of ash are produced and must be disposed of properly i. Bottom ash (slag) ii. Fly ash c. High cost iii. Compost it II. Waste Prevention a. Reducing the amount of waste: source reduction i. The most underutilized aspect of waste management is source reduction 1. Purchase products with less packaging and that last longer or are repairable 2. Reduce consumption ii. Dematerialization is an example of source reduction iii. The Pollution Prevention Act (1990) was the first U.S. environmental law to focus on the reduced generation of pollutants at their point of origin b. Reusing products c. Recycling materials i. Preferred over landfill disposal because it conserves our natural resources and is more environmentally benign ii. Recycling has a positive effect on the economy iii. Recyclables are usually sent to a materials recovery facility iv. Currently, the U.S. recycles about 32% of its municipal solid waste v. Recycling paper 1. The U.S. currently recycles about 50% of its paper and paperboard 2. There is a growing demand for U.S. wastepaper in other countries vi. Recycling glass 1. The U.S. currently recycles about 25% of its glass containers 2. Glass food and beverage containers are crushed to form cullet vii. Recycling aluminum 1. Making a new aluminum can from a recycled one requires a fraction of the energy it would take to make a new can from raw material 2. Strong economic incentive drives aluminum recycling viii. Recycling metals other than aluminum

Chapter 23 1. Other recyclable metals include lead, gold, iron and steel, silver, and zinc 2. Greater recycling generally occurs when the economy is strong than when there is a recession ix. Recycling plastic 1. Less than 20% of plastic is recycled, mainly due to economic reasons 2. Recycled plastic is used to make carpeting, automobile parts, tennis ball felt, and polyester cloth x. Recycling tires 1. About 290 million tires are discarded in the U.S. each year 2. Recycled tires can be used for playground equipment, trashcans, garden hoses, and rubberized asphalt for pavement d. Integrated waste management uses a combination of the best waste management techniques to deal effectively with solid waste III. Hazardous Waste a. Hazardous waste accounts for about 1% of the solid waste stream in the U.S. b. The Superfund law holds polluters accountable for the cost of hazardous waste cleanup c. Types of hazardous waste i. Dioxins 1. A group of 75 similar chemical compounds formed as unwanted byproducts during the combustion of chlorine compounds 2. Dioxins are emitted in smoke and then settle on plants, the soil, and bodies of water; from there they are incorporated into the food web 3. Dioxins are known to cause several kinds of cancer in laboratory animals 4. Dioxins may have an effect on the human reproductive, immune, and nervous systems ii. PCBs 1. Polychlorinated biphenyls (PCBs) are a group of 209 industrial chemicals composed of carbon, hydrogen, and chlorine 2. PCB toxicity tests reveals that they harm skin, eyes, reproductive organs, the gastrointestinal system, and are endocrine disrupters 3. Several studies suggest that PCBs may be carcinogenic d. Management of hazardous waste i. We have the technology to manage hazardous waste in an environmentally responsible way, but it is extremely expensive ii. No country currently has an effective hazardous waste management program iii. Chemical accidents 1. When a chemical accident occurs in the U.S. the National Response Center (NRC) is notified 2. Most involve oil, gasoline, petroleum spills or one of more than 1000 other hazardous materials (i.e., PCBs, ammonia, sulfuric acid, and chlorine) 3. Industry and government agencies have focused on accident prevention through the principle of inherent safety

Chapter 23 iv. Current management policies 1. The Resource Conservation and Recovery Act (1976, 1984, 1992) 2. The Superfund Act (1980) v. Cleaning up existing hazardous waste: the superfund program 1. The U.S. has more than 400,000 hazardous waste sites with leaking chemical storage tanks and drums, pesticide dumps, and piles of mining waste 2. These sites are not identified according to any particular criteria a. Sites placed on the Superfund National Priorities List will be given government assistance in their cleanup b. As of 2006, 1558 sits were on this list c. One in three Americans lives within 5km (3mi) of one or more Superfund sites vi. The biological treatment of hazardous contaminants 1. Bioremediation is the use of bacteria and other microorganisms to break down hazardous waste into relatively harmless components 2. Phytoremediation is the use of plants to absorb and accumulate hazardous materials from the soil 3. More than 1,000 species of bacteria and fungi have been demonstrated to clean up various forms of pollution vii. Managing the hazardous waste we are producing now 1. Source reduction relies on environmental chemistry (green chemistry) 2. Conversion to less hazardous materials 3. Long-term storage a. Currently there are only 23 commercial hazardous waste landfills in the U.S. b. Some liquid hazardous wastes are stored in the Earth’s crust by deep well injection i. Fuels ii. Explosives, iii. Pesticides iv. Organic compounds IV. Environmental Justice a. Environmental justice and ethical issues i. Many advocates of environmental justice are calling for special efforts to clean up hazardous sites in low-income neighborhoods ii. Groups base their demands on the inherent “rightness” of their position b. Mandating environmental justice at the federal level c. Environmental justice and international waste management i. The export of both solid and hazardous wastes by the U.S., Japan, and the European Union is one of the most controversial aspects of waste management today ii. The Basel Convention (1989) restricts the international transport of hazardous waste V. Meeting the Challenge: Municipal Solid Waste Composting a. A large-scale composting of the entire organic portion of a community’s garbage

Chapter 23 b. Two-thirds of all household garbage is organic c. Initial composting occurs quickly, in three to four days d. The potential market for compost is huge

Chapter 23

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Brownfield Management

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: Cleaning contaminated industrial sites is a waste of money. The same amount of money could be better spent sealing off those areas from human intrusion, and investing in improvements in less contaminated areas.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Chapter 23 Student See above Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Explain the challenges associated with managing brownfield sites.

Chapter 23

Instructor Notes for In-Class Activity 2 Title:

Reduction, Reuse and Recycling at Campus Dining Facilities

Time: Materials: Handouts:

5 minutes prep; Full class period Campus map None

Procedures:

Have students visit various camping dining options, including vending machines, portable carts, cafes and dining commons. At each location, have them identify current practices and future opportunities for reducing materials use (including wasted food), reusing material, and recycling materials.

Have them list what they think to be the drivers of current practices. Are they best explained by • Convenience?

• Economics?

• Social norms and habits?

• Other (explain) Have them list some constraints that limit adoptions of future reduction, reuse and recycling.

Student Instructions:

Regroup as a class and discuss the students’ findings.

See above

Specific Suggestions:

An expanded version of this could make a good senior thesis project.

Objectives:

Describe some opportunities to reduce materials use, adopt reusable materials, and recycle used materials.

Chapter 23

Instructor Notes for In-Class Activity 3 Title:

Individual Solid Waste Generation

Time: Materials: Handouts:

5 minutes prep; 15 – 30 minutes in class None None

Procedures:

Have students log every object that they throw into the garbage for two days to one week.

Have them then categorize these objects as: • Paper and paperboard • Yard Waste • Food Waste • Plastics • Metals • Rubber, latex and textiles • Glass • Wood • Other How closely does their waste stream reflect figure 24.1 in the book?

What might account for this difference?

How much of this waste could have been avoided by: • Reducing reliance on disposable materials • Reusing some of these materials • Recycling some of the materials.

Do any of your students’ compost food and yard waste? How much of a difference does it make?

Ask whether any of the students changed their habits because they were keeping track.

Student For the amount of time assigned by your instructor, keep track of Instructions: everything you throw in the garbage. Categorize it as: • Paper and paperboard • Yard Waste • Food Waste • Plastics • Metals • Rubber, latex and textiles • Glass • Wood

Chapter 23 • Other If possible, estimate the weight of garbage in each of these categories.

Specific Suggestions:

None

Objectives:

Describe municipal waste, and explain opportunities for waste reduction.

Chapter 23

Instructor Notes for In-Class Activity 4 Title:

Visit to the local landfill

Time: Materials: Handouts:

10 – 20 minutes prep; full class period None None

Procedures:

As a class visit the local city landfill. This is very interesting and the landfill management systems are usually very helpful on taking the students on the tour. Before the student visit the landfill, you might invite the management to your class and have them bring their presentation. In our city they are very proud of their landfill and have many interesting points to bring up along with some garbage quartz for the class to examine.

Student See above Instructions: Specific Suggestions: Objectives:

Define integrated waste management.

Chapter 23

Instructor Notes for In-Class Activity 5 Title:

Dumpster diving

Time: Materials: Handouts:

10 – 20 minutes prep; full class period Latex gloves None

Procedures:

You would need permission from your school or school board. Have the students on a Saturday wear clothes they do not mind to get ripped or smelly and have them go through the trash in the dumpster. They would record all the types of trash they find, which would mainly be paper, plastic and other waste. Have students on the side taking notes of all the “recyclables” they find in the dumpster.

A substitute for this would be have the students go through their trash at home and divide out the paper, plastic, metal, food, etc. and report to class what they found.

Student See above Instructions: Specific Suggestions:

You would have to search out the safety factors for this activity.

Accessibility to the dumpster and getting in and out of the dumpster might be an issue.

If you choose to go dumpster diving or even check the trash from your home trash cans it is a good idea to wear latex gloves.

Objectives:

Describe the contents of solid waste.

Chapter 23

Answers to Critical Thinking and Review End of Chapter Questions: 1. What is solid waste?

Ans: There are two types of solid waste, municipal and nonmunicipal. Municipal solid waste is a heterogeneous mixture composed primarily of paper and paperboard; yard waste; plastics; food waste; metals; materials such as rubber, leather, and textiles; wood; and glass. Municipal solid waste is a relatively small portion of all the solid waste produced. Nonmunicipal solid waste, which includes wastes from mining, agriculture and industry.

2. Compare the advantages and disadvantages of disposing of waste in sanitary landfills and by incineration.

Ans: A sanitary landfill is the most common method of disposal of solid waste, by compacting it and burying it under a shallow layer of soil. Despite design features such as high-density plastic liners and leachate collection systems, most sanitary landfills have the potential to contaminate soil, surface water, and groundwater. A mass burn incinerator is a large furnace that burns all solid waste except for unburnable items such as refrigerators. Most mass burn incinerators recover the energy produced from combustion. One drawback of incineration is the great expense of installing pollution control devices on the incinerators.

3. List what you think are the best ways to treat each of the following types of solid waste, and explain the benefits of the processes you recommend: paper, plastic, glass, metals, food waste, yard waste.

Ans: Answers will vary.

4. How do industries such as Goodwill, which accepts donations of clothing, appliances, and furniture for resale, affect the volume of solid waste?

Ans: Companies that resell used items help reduce the amount of solid waste that ends up in landfills. They also help to reduce the amount of source materials produced.

5. Why is creating a demand for recycled materials sometimes referred to as “closing the loop”?

Ans: For recycling to work, there must be a market for the recycled goods, and the recycled products must be used in preference to virgin products. By creating a demand for recycled products, one continues to reduce sources and reuse original resources - thus ‘closes the loop’.

6. How does recycling link the world's largest economy (the United States) to the world's fastest growing economy (China)?

Ans: During the early 2000s, China became the biggest importer of America's recyclable materials, collectively called scrap. When the scrap arrives in China, it becomes the raw materials for Chinese factories, paper mills, and steel mills. To fuel its economic growth, China relies on scrap—used paper to replace its dearth of wood pulp and steel scrap to replace its

Chapter 23 dearth of iron ore. Some of the scrap shipped from the United States to China makes a roundtrip, returning to the United States as auto parts, polyester shirts, and toys.

7. What are dioxins, and how are they produced? What harm do they cause?

Ans: Dioxins are hazardous chemicals formed as unwanted by-products during the combustion of many chlorine compounds. When humans and other animals ingest dioxins, they are stored and accumulate in their fatty tissues. Dioxins are known to cause several kinds of cancer in laboratory animals, but the data are conflicting on their cancer-causing ability in humans.

Dioxins may delay fetal development and cause cognitive damage, lead to endometriosis in women and decrease sperm production in men.

8. Suppose hazardous chemicals were suspected to be leaking from an old dump near your home.

Outline the steps you would take to (1) have the site evaluated to determine if there is a danger and (2) mobilize the local community to get the site cleaned up.

Ans: Answers will vary.

9. What are the goals, strengths, and weaknesses of the Superfund program?

Ans: The Comprehensive Environmental Response, Compensation, and Liability Act, also known as the Superfund Act, addresses the challenge of cleaning up abandoned and illegal hazardous waste sites in the United States. The sites that pose the greatest threat to public health and the environment are placed on the Superfund National Priorities List, which means that the federal government will assist in their cleanup. The cleanup process has been mired in litigation, mostly by companies, charged with polluting, who are suing each other. Despite the urgency of cleaning up sites on the National Priorities List, it will take many years to complete the job.

10. The Organization for African Unity has vigorously opposed the export of hazardous waste from industrialized countries to developing nations. They call this practice “toxic terrorism.”

Explain.

Ans: Although there are ways to reduce and dispose of waste in an environmentally sound manner, industrialized countries have sometimes chosen to send their waste to other countries.

Some waste is exported for legitimate recycling, but other waste is exported strictly for disposal.

Many studies indicate that poor minority neighborhoods are more likely to have hazardous waste facilities, sanitary landfills, sewage treatment plants, and incinerators in their neighborhoods.

Because people developing nations frequently lack access to sufficient health care, they may not be treated adequately for exposure to environmental hazards.

11. What is integrated waste management? Why must a sanitary landfill always be included in any integrated waste management plan?

Ans: Integrated waste management is a combination of the best waste management techniques into a consolidated program to deal effectively with solid waste. Even on a large scale, recycling and source reduction will not entirely eliminate the need for disposal facilities such as

Chapter 23 incinerators and landfills. However, recycling and source reduction will substantially reduce the amount of solid waste requiring disposal in incinerators and landfills.

12. Compare integrated pest management, discussed in Chapter 22, to integrated waste management. How does each reduce potential damage to the environment?

Ans: Integrated pest management (IPM) is a systems approach that combines several pest control methods that, if used in the proper order and at the proper times, keep the size of a pest population low enough that it does not cause substantial economic loss. In integrated waste management, a variety of options that minimize waste, including the three R's of waste prevention (reduce, reuse, and recycle), are incorporated into an overall waste management plan.

Both help reduce potential damage to the environment by reducing the amount of toxins released and produced.

13. How does the system of integrated waste management depicted in Figure 23.10 compare to a natural ecosystem?

INSERT FIGURE 23.10 Ans: The raw material depicted could be analogous to the nutrients present in the environment.

The processing and manufacturing component of integrated waste management compares to the primary producers in a natural ecosystem with consumers following. The paper, glass, metal and plastic recycling are like the decomposers returning raw materials/ nutrients to the primary producers/ manufacturing.

14. How do the three R’s of waste prevention reduce the release of climate-altering CO2 into the environment?

Ans: Anytime we consume less (reduce) or reusing products we use less energy thereby emitting less carbon. There are numerous examples of how recycling saves energy. Every ton of recycled paper saves 17 trees, 7000 gallons of water, 4100 kilowatt-hours of energy, and 3 cubic yards of landfill space. Making a new aluminum can from a recycled one requires a fraction of the energy it would take to make a new can from raw metal. By one estimate, making polyester fabric from recycled garments saves 76% of the energy needed to make new polyester; this energy savings results in a reduction of greenhouse gases of about 71%.

15. In an effort to reduce municipal solid waste, some communities require customers to pay for garbage collection according to the amount of garbage they generate, known as unit pricing. The figure below shows the effects of unit pricing in San Jose, California, on garbage sent to landfills, on wastes diverted through recycling, and on separation of yard wastes. How did unit pricing affect the amount of garbage sent to landfills? How did unit pricing affect the quantity of materials recycled? of yards wastes collected?

INSERT FIGURE FROM THIS QUESTION PAGE 500 Ans: Unit pricing reduced the amount of garbage sent to landfills by 50,000 tons. It double the amount of materials recycled and increased the amount of yard waste collected.

Chapter 23

Answers to Review Questions Solid Waste 1. What is the difference between municipal solid waste and nonmunicipal solid waste?

Municipal solid waste consists of solid materials discarded by homes, office buildings, retail stores, restaurants, schools, hospitals, prisons, libraries, and other commercial and institutional facilities. It is a heterogeneous mixture composed primarily of paper and paperboard; yard waste; plastics; food waste; metals; materials such as rubber, leather, and textiles; wood; and glass. Nevertheless, it is a relatively small portion of all the solid waste produced. Nonmunicipal solid waste makes up the majority of solid waste in the United States. It consists of solid waste generated by industry, agriculture, and mining.

2. What are three features of a sanitary landfill?

A sanitary landfill is the most common method of disposal of solid waste; it receives about 54% of the solid waste generated in the United States today. In sanitary landfills, waste is compacted and buried under a shallow layer of soil. Features of a sanitary landfill include (1) the fact that solid waste is placed in a hole, compacted, and covered with a thin layer of soil everyday, (2) regulations to limit the pollution of local surface water and groundwater, (3) leachate collection systems, (4) suitable location selection (i.e., appropriate geology, soil drainage properties, and proximities to nearby bodies of water), and (5) appropriate distance from urban populations. Additionally, sanitary landfill designs often take into account local climate factors, such as rainfall, snowmelt, and the likelihood of flooding.

3. What are the main features of a mass burn incinerator?

A mass burn incinerator is a large furnace that burns all solid waste except for unburnable items such as refrigerators. Most mass burn incinerators are designed to recover the energy produced from combustion. Modern incinerators have pollution-control devices such as lime scrubbers and electrostatic precipitators to trap dangerous and dirty emission. These controls reduce the toxicity of the gaseous emissions from incinerators but make ash that remains behind more hazardous. These features also lead to one of the main drawbacks of incineration; that is, the great expense of installing pollution-control devices on the incinerators.

Waste Prevention 1. What is source reduction?

Chapter 23 Source reduction is an aspect of waste management in which products are designed and manufactured in ways that decrease the volume of solid waste and the amount of hazardous waste in the solid waste stream.

2. How do source reduction, reuse, and recycling reduce the volume of solid waste?

Reducing the overall volume of solid waste depends on reducing as much waste as possible (source reduction), reusing as many products as possible, and recycling materials as much as possible. To elaborate, reducing the amount of waste includes purchasing products that last longer, are repairable, or have less packaging (i.e., dematerialization).

Another behavior that can greatly reduce the volume of solid waste is by encouraging consumers to decrease their overall consumption of products.

3. What is integrated waste management?

Integrated waste management is a combination of the best waste management techniques into a consolidated, systems-based program to deal effectively with solid waste.

Hazardous Waste 1. What is hazardous waste?

Hazardous waste consists of any discarded chemical that threatens human health or the environment. It includes dangerously reactive, corrosive, ignitable, or toxic chemicals.

The chemicals may be solids, liquids, or gases.

2. How are the Resource Conservation and Recovery Act and the Comprehensive Environmental Response, Compensation, and Liability Act alike? What is the focus of each?

The Resource Conservation and Recovery Act instructs the Environmental Protection Agency to identify which waste is hazardous, and provides guidelines and standards to states for hazardous waste management programs. It bans hazardous waste from land disposal unless it is treated to meet the EPA’s standards of reduced toxicity. The Comprehensive Environmental Response, Compensation, and Liability Act addresses the challenge of cleaning up abandoned and illegal hazardous waste sites in the United States. Both law dictate how hazardous waste should be managed.

3. How does green chemistry relate to source reduction?

Green chemistry is a subdiscipline of chemistry in which commercially important chemical processes are redesigned to significantly reduce environmental harm. Source reduction is the best way to reduce hazardous waste, so green chemists redesign processes with source reduction in mind.

Chapter 23

Chapter 24 Tomorrow’s World Lecture Outline: I. Living Sustainably A. Environmental sustainability is the ability to meet humanity’s current needs without compromising the ability of future generations to meet their needs B. Sustainable development is economic development that meets the needs of the present without compromising the ability of future generations to meet their own needs i. It balances economic growth with environmental conservation ii. There can be no overall sustainability unless the needs of the world’s poor are met iii. The number of people existing, their degree of consumption, and their choices of technology all interact to produce the total effect of a given society on the sustainability of the environment C. All economic development inevitably must take place within the carrying capacity of the ecosystems that support it II. Sustainable Living: A Plan of Action A. Five recommendations for sustainable living i. Eliminating poverty and stabilizing the human population 1. Improve the quality of human life 2. Improve the status of women 3. An improving economy is generally one of the most important factors that leads away from poverty 4. There is no hope for a peaceful world without overall population stability, and no hope for regional economic sustainability without regional population stability ii. Protecting and restoring Earth’s resources 1. To build and maintain a sustainable society, it is necessary to preserve the productive natural systems that support us 2. Ensure long-term productivity of renewable resources 3. Conserve non-renewable resources 4. The world’s forests a. Forests are being exploited and sold b. Few nations have forestry plans, and there is almost no coordination of forestry policies 5. Loss of biodiversity a. We still have limited knowledge about the world’s biological diversity b. We obtain all our food, most medicines, building and clothing materials, biomass for energy, and numerous other products from living organisms

Chapter 24 c. Communities of organisms and ecosystems provide an enormous array of ecosystem services without which we would not survive d. Economic development will only succeed if it is carried out in such a way as to maintain the sustainable productivity of the biosphere e. Biological diversity and human cultural diversity are intertwined iii. Providing adequate food for all people 1. Globally, more than 800 million people lack access to food needed for healthy, productive lives 2. The link between poverty and food insecurity is inescapable 3. Improving agriculture is one the highest priorities 4. Farmlands and grazing lands must be managed efficiently 5. Agricultural systems that provide improved dietary standards must be developed iv. Mitigating climate change 1. Both highly developed and developing countries contribute to the enhanced greenhouse effect 2. Stabilizing the climate requires a comprehensive energy plan a. Worldwide, we must phase out fossil fuels in favor of renewable energy, increase energy conservation, and improve energy efficiency b. We need a global consensus to address climate change v. Designing sustainable cities 1. There is an urgent need to improve the environment and quality of life in cities, particularly in rapidly growing megacities of developing countries 2. How to design a sustainable city a. Develop urban transport systems b. Encourage small-scale urban farms c. Adopt innovative approaches for water conservation and use d. Improve squatter settlements B. Addressing these recommendations now offers us hope for the kind of future we all want for our children and grandchildren III. Changing Personal Attitudes and Practices A. Any long-term improvement in the condition of the world must start with individuals; each of us makes a difference and our collective activities make the world what it is B. Consumption overpopulation reflects the growing idea that much of the world’s environmental and resource problems stem from the lifestyles of people living in highly developed nations C. The use of goods and services that satisfy basic human needs and improve the quality of life but that minimize the use of resources so they are available for future generations is called sustainable consumption D. The role of education

Chapter 24 i. If people understand the way the natural world functions, they can appreciate their own place in it and value sustainable actions ii. Most people are interested in the environment – their own local environment – in their own way IV. What Kind of World Do We Want?

A. At the deepest level, the most critical environmental problems, from which all others arise, are our own attitudes and values B. We are out of touch and out of balance with the natural world C. The choices we make now will have a greater impact on the future than those that any generation has had before D. Even choosing to do nothing will have profound consequences for the future

Chapter 24

In-Class Activities: Instructor Notes for In-Class Activity 1 Title:

Can Technology Solve Famine, Water Shortages and Threats to Environmental Health?

Time:

5 – 10 Minutes prep; 40 – 60 minutes in class (or can assign research between class periods) None None

Materials: Handouts: Procedures:

For – Against – Jury standard procedure. Randomly divide class into three groups.

Statement: The best strategy to reduce worldwide hunger, water shortages, illness and environmental degradation is to invest in technological solutions.

Assign one group each to argue FOR or AGAINST the statement, and the third group to serve as a JURY. Each group should select a leader and a recorder.

The FOR group should research (not just think up!) information that supports the statement. They should be explicit about their sources, whether those are data, ethics, theories, or political positions. They should then synthesize this into a five-minute verbal argument, to be made before the full class.

The AGAINST group should do the same for the opposite position. Their original argument SHOULD NOT respond to items brought up by the FOR group.

After each has made a five-minute argument, each side will have two minutes to respond to claims or statements made by the other side.

The JURY group will then deliberate openly; the FOR and AGAINST groups will listen to the deliberations, but may not respond. The JURY may challenge either group to provide evidence for up to three pieces of information, and may ask up to three questions of each group (they may ask the same question to both groups).

The JURY should then make two judgments: 1. Which, if either, provided the most credible INFORMATION 2. Which provided the most compelling overall argument.

3. Be sure students argue their points forcefully, whether or not they believe them personally.

Chapter 24 Student See above Instructions: Specific Suggestions:

The instructor is likely to have to serve as a facilitator or moderator from time to time 1. Do not allow personal assaults 2. Feel free to challenge pieces of information that you find dubious if the JURY does not.

It will probably take a couple times through this debate process before you and your class are comfortable with it.

Objectives:

Explain the advantages and disadvantages of technological solution to technical problems.

Chapter 24

Instructor Notes for In-Class Activity 2 Title:

Individual Resource Reduction Options

Time: Materials: Handouts:

5 minutes prep; 15 – 20 minutes in class None None

Procedures:

Have each student consider the easiest way to cut personal resource production in half.

This might include: • Reduced energy • Switching from a car to public transportation • Changing eating habits • Showering and / or washing clothes less frequently • Switching to reusable products Next, have them discuss: • How much of an impact would this have on a student’s life?

• How big an impact on world resource use would there be if EVERY American cut resource use in half?

• How plausible would this level of reductions be?

• What would be the impact on total world resource use every person on the planet used resources at half the current US rate?

Student See above Instructions: Specific Suggestions: Objectives:

Describe some of the challenges confronting our efforts to improve the quality of human life worldwide.

Chapter 24

Instructor Notes for In-Class Activity 3 Title:

Local Environmental Future

Time: Materials: Handouts:

5 minutes prep; 15 – 30 minutes in class None None

Procedures:

Have students read the statement below and then discuss: • Do they expect that environmental conditions that affect them will improve, worsen, or do some of each over their lifetimes?

• What world environmental issues might impact them indirectly?

• What actions by individuals or governments might improve or harm the global environment over their lifetimes?

Statement: • In many parts of the US and in many ways, environmental quality improved starting in the 1970’s.

• In some situations, though—for example, Los Angeles air quality— this progress has begun to reverse.

• At the same time, we have become aware of new, more intractable environmental threats, such as hormone disruptors, climate change and fishery collapses.

Student See above Instructions: Specific Suggestions: Objectives:

Describe your expectations for future environmental quality, and options for improving future environmental quality.

Chapter 24

Instructor Notes for In-Class Activity 4 Title:

What in the world do you see?

Time: Materials: Handouts:

10 – 20 minutes prep; full class period Campus map None

Procedures:

As a class or in groups, ask the question: what in the world do you see and appreciate most? Will it be there for your children?

Have them make a list of the things they appreciate and what they want for their children. Then have them take that list to their parents or someone born before 1960 and ask them the same questions. Make a note what they appreciate and see if it is here for them today. You may get a different list. Also, it helps the student think about the changes that our society and world go through during the decades.

Have the students look around at the shopping centers that use to be open land. Look at the forests which used to be thicker. Look at the glaciers that are no more. These are the things that will disappear before our children can realize they are here.

Now what can we do to stop the decline of our forests, grasslands, glaciers and animals. How can students get involved? Listen to their arguments and beliefs. You usually don’t appreciate something until it is gone.

Student See above Instructions: Specific Suggestions: Objectives:

• •

Discuss at least two important environmental goals that can be accomplished most effectively at the national and international levels.

Describe some of the challenges confronting our efforts to improve the quality of human life worldwide.

Chapter 24

Answers to Critical Thinking and End of Chapter Questions: 1. What is environmental sustainability? How are people in highly developed countries not living sustainably? How are people in developing countries not living sustainably?

Ans: Environmental sustainability is the ability to meet humanity's current needs without compromising the ability of future generations to meet their needs. The world does not contain nearly enough resources to sustain everyone at the level of consumption enjoyed in the United States, Europe, and Japan; although countries such as China are rapidly catching up. Global warming is underway, with greater than one-sixth more carbon dioxide (CO2) having been added to the total amount in Earth's atmosphere since 1950, mainly by developed nations. In both developed and developing countries, we have cut about a third of the forests since 1950 without replacing them and we are driving the world's species of plants, animals, fungi, and microorganisms to extinction at a rate thousands of times faster than that of the past 65 million years. Worldwide, more and more people are living in urban areas. This influx into cities has resulted in unsafe, unhealthy environments for many residents, particularly in developing countries.

2. How are the natural environment and sustainable development linked?

Ans: Sustainable development is economic development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Earth's productivity is limited, and our use of it at the current level can not be extended indefinitely.

Sustainable development must allow for the maintenance of the life-support systems on which our lives and the lives of all other species are based.

3. What are the consumption habits of people in highly developed countries? How is consumption related to human carrying capacity?

Ans: Consumption is the human use of materials and energy; generally speaking, people in highly developed countries are extravagant consumers. Carrying capacity is the maximum number of individuals of a given species that a particular environment can support for an indefinite period, assuming there are no changes in the environment. The world does not contain enough resources to sustain more than 6 billion people at the level of consumption enjoyed in the United States.

4. What are the five recommendations for sustainable living discussed in this chapter.

Ans: 1.

2.

3.

4.

5.

Eliminating poverty and stabilizing the human population Protecting and restoring Earth’s resources Providing adequate food for all people Mitigating climate change Designing sustainable cities

5. How pervasive is poverty around the world?

Chapter 24

Ans: Currently, almost 3.5 billion people, more than half of the world's population, live on less than $2 per day. For many of the world's women and children, life is an endless struggle for survival, centering on the daily requirements for firewood, clean water, and food.

6. What important ecosystem services does biological diversity provide?

Ans: Biological diversity, the number and variety of Earth's organisms, is declining at an alarming rate. Humans are part of Earth’s web of life and are entirely dependent on that web, with all its interactions, for our survival. Organisms and their ecosystems provide important ecosystem services, environmental benefits, such as clean air to breathe, clean water to drink, and fertile soil in which to grow crops.

7. How pervasive is food insecurity around the world?

Ans: Food insecurity is the condition in which people live with chronic hunger and malnutrition.

Globally, more than 900 million people lack access to the food needed for healthy, productive lives.

8. Describe three serious problems associated with megacities in the developing world.

Ans: A megacity is a city with more than 10 million inhabitants. The air in megacities in the developing world is badly polluted with the exhaust from motor vehicles, which also congest roads and require large areas for parking. Illegal squatter settlements proliferate in megacities; here the poorest inhabitants build dwellings on vacant land using whatever materials they can scavenge. Squatter settlements have the worst water, sewage, and solid waste problems. Water pollution and access to clean water are both serious problem in megacities.

9. Explain how unsustainable consumption threatens environmental sustainability.

Ans: Unsustainable consumption is a situation that occurs when each individual in a population consumes too large a share of resources. Many of the world's environmental and resource problems that threaten environmental sustainability stem from consumption overpopulation-the extravagant lifestyles of people living in highly developed nations.

10. What is sustainable consumption?

Ans: Sustainable consumption is the use of goods and services to satisfy basic human needs and improve the quality of life, and while at the same time, minimize the use of resources so that they are available for future generations.

11. Discuss four specific environmental goals that you hope are achieved in your lifetime.

Ans: Answers will vary.

12. How is stabilizing climate related to fossil fuel use?

Chapter 24 Ans: Both highly developed and developing countries contribute to major increases in CO2 in the atmosphere, as well as to the increasing amounts of the greenhouse gases methane, nitrous oxide, methane, and CFCs. An increase in atmospheric CO2, mostly produced when fossil fuels are burned, leads to climate warming. To stabilize climate, we must phase out fossil fuels in favor of renewable energy, increased energy conservation, and improved energy efficiency.

13. At home, place an uncracked egg in a small bowl and cover it with vinegar. Allow it to sit in the vinegar for 24 hours. Take the egg out and examine the shell. How does this simple experiment demonstrate a possible effect of increased atmospheric CO2 on marine organisms with calcium carbonate shells?

Ans: Higher levels of atmospheric CO2 are now resulting in increased levels of dissolved CO2 in the ocean. This change profoundly alters ocean chemistry, which in turn will affect marine organisms. The high levels of dissolved CO2 in the ocean dissolves the calcium carbonate shells of organisms, possibly leading to the extinction of some or many species.

14. Explain why the global increase in CO2 is not a simple cause and effect relationship with climate warming but instead a cascade of interacting responses that ripple through the Earth’s system.

Ans: We may never have a complete scientific understanding of Earth as a system.

For example, increasing atmospheric CO2 also affects how plants grow, but different species react to increasing CO2 in different ways; we can expect changes in plant community composition as the plants that are more competitive in the new conditions thrive and replace less competitive plants. We cannot begin to predict how these vegetation changes will affect humans or the rest of the biosphere.

An example of the cascading effects of a single change (increasing levels of atmospheric CO2), the higher levels of atmospheric CO2 are now resulting in increased levels of dissolved CO2 in the ocean. This change profoundly alters ocean chemistry, which in turn affects marine organisms, possibly leading to the extinction of some or many species.

Answers to Review Questions Living Sustainably 1. What is environmental sustainability?

Environmental sustainability is the ability to meet humanity’s current needs without compromising the ability of future generations to meet their needs.

2. How is the natural environment – Earth’s living organisms and ecosystems – an essential part of sustainable development?

The goals of sustainable development are to improve living conditions for all people while maintaining a healthy environmental system in which natural resources are not

Chapter 24 overused and excessive pollution is not generated. Sustainable development also aims to balance economic growth with environmental conservation. Therefore, it is imperative that Earth’s living organisms (i.e., humans) and ecosystems are maintained and conserved to ensure sustainable development.

3. How are human consumption habits related to Earth’s carrying capacity?

Consumption is the human use of materials and energy, and the carrying capacity of a given ecosystem is determined by its ability to absorb wastes and renew itself. Therefore, it is essential that when assessing the carrying capacity of the Earth, the great disparities between human consumption behaviors (i.e., living standards and expectations) of different areas (i.e., highly developed countries versus developing countries) are considered. For example, the world does not contain enough resources to sustain more than 6 billion people at the level of consumption enjoyed in the United States. To live within the Earth’s carrying capacity, population size must be held at a sustainable level, and the wealthy must first stabilize their use of natural resources and then reduce this use to a level that can be maintained.

Sustainable Living: A Plan of Action 1. What is the global extent of poverty?

At present, nearly 3.5 billion people, about half of the world’s population, live on less than $2 per day. $2 per day is not adequate to allow people to meet their basic needs for food, clothing, shelter, education, or health.

2. What are two ecosystem services that natural resources such as forests and biological diversity provide?

Natural resources such as forests and biological diversity provide a myriad of ecosystem services for humans. For example, ecosystem services provided by the world’s forests include nutrient recycling, watersheds, clean air, wildlife habitats, and wood for energy source. Likewise, biological diversity provides ecosystem services such as food, medicine, building materials, clothing, and biomass for energy.

3. What is the global extent of food insecurity?

Food insecurity is the condition in which people live with chronic hunger and malnutrition. Globally, about 1 million people lack access to the food needed for healthy, productive lives.

4. How is stabilizing climate related to energy use?

Chapter 24 To stabilize climate, we must phase out fossil fuels and replace them with renewable energy, increased energy conservation, and improved energy efficiency.

5. What are two serious problems in megacities in the developing world?

A megacity is a city with more than 10 million inhabitants. Serious environmental problems associated with megacities include air pollution, water pollution, groundwater depletion, and sizeable illegal squatter settlements.

Changing Personal Attitudes and Practices 1. How does unsustainable consumption affect environmental sustainability?

Many of the world’s environmental and resource problems that threaten environmental sustainability stem from unsustainable consumption – the wasteful lifestyles of people living in highly developed countries.

2. What is sustainable consumption?

Sustainable consumption is the use of goods and services that satisfy basic human needs and improve the quality of life but that minimize the use of resources so that they are available for future generations.

What Kind of World Do We Want?

1. How would you describe the world you want your children to live in? How does the future world you envision differ from the realities of today?

Answers will vary.

Students may mention and elaborate on ideas such as Environmental Revolution, reinventing economic constructs, creating social change, preservation of Earth’s natural resources, voluntary simplicity, etc.

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: 1

Question Type: Multiple Choice

1. Use the I=PAT equation to calculate the environmental impact in terms of CO2 emissions per year at the beginning of the 21st Century, when there were 6 billion people, an average of 0.1 motor vehicles per person, and 5.4 tons of CO2 emitted by each car per year. a) 3.24 trillion tons of carbon b) 6.48 billion tons of carbon c) 3.24 billion tons of carbon d) 16.1 billion tons of carbon Answer: c Difficulty: Easy Learning Objective 1: LO 1.2.0 Explain how humans impact the environment.

Learning Objective 2: LO 1.2.1 Explain how both population and affluence can lead to unsustainable consumption.

Section Reference 1: 1.2 Population, Resources, and the Environment 2. According to the UN, 40% of the world’s human population lives in poverty. Using the 2008 population estimate of 6.9 billion, calculate approximately how many individuals are living in poverty. a) 276 million b) 1.76 billion c) 2.76 billion d) 4.76 billion Answer: c Difficulty: Easy Learning Objective 1: LO 1.1.0 Compare and contrast highly, moderately, and less developed countries.

Learning Objective 2: LO 1.1.2 Distinguish among highly developed countries, moderately developed countries, and less developed countries.

Section Reference 1: 1.1 Human Impacts on the Environment

3. Calculate how long it took for Earth's population to double from 3 to 6 billion.

a) 10 years b) 20 years c) 30 years d) 40 years Answer: d Difficulty: Easy Learning Objective 1: LO 1.1.0 Compare and contrast highly, moderately, and less developed countries.

Learning Objective 2: LO 1.1.2 Distinguish among highly developed countries, moderately developed countries, and less developed countries.

Section Reference 1: 1.1 Human Impacts on the Environment

4. Identify the year in which almost 100% of the phosphorus in Lake Washington was attributed to sewage effluent.

a) 1955 b) 1960 c) 1963 d) 1966 Answer: d Difficulty: Medium Learning Objective 1: LO 1.5.0 Describe the analysis procedures used to evaluate environmental problems.

Learning Objective 2: LO 1.5.2 Briefly describe the history of the Lake Washington pollution problem of the 1950s and how it was resolved.

Section Reference 1: 1.5 Addressing Environmental Problems

5. According to the UN, nearly 2.8 billion people subsist on less than $2US a day (adjusted for purchasing power). Assuming that Earth's human population is approximately 6.9 billion people in 2009, what percentage subsists on less than $2US per day? a) 30% b) 41%

c) 61% d) 70% Answer: b Difficulty: Easy Learning Objective 1: LO 1.1.0 Compare and contrast highly, moderately, and less developed countries.

Learning Objective 2: LO 1.1.2 Distinguish among highly developed countries, moderately developed countries, and less developed countries.

Section Reference 1: 1.1 Human Impacts on the Environment

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: 2

Question Type: Multiple Choice

1. As the amount of pollution in an environment is reduced, the cost of removing the remaining pollution:

a) increases b) decreases c) is the same as when the pollution abatement began d) can’t be calculated from this graph Answer: a

Difficulty: Easy Learning Objective 1: LO 2.3.0 Explain the economic cost of pollution.

Learning Objective 2: LO 2.3.1 Explain why economists prefer efficient solutions to environmental problems.

Section Reference 1: 2.3 Economics and the Environment

2. By 1897, loggers in Michigan had removed 160 billion board feet of white pine, leaving only 6 billion board feet. What percent of the original board feet of white pine remained?

a) 2% b) 4% c) 8% d)16% Answer: b Difficulty: Easy Learning Objective 1: LO 2.1.0 List the contributions made by individuals during the environmental movement in the United States.

Learning Objective 2: LO 2.1.1 Briefly outline the environmental history of the United States.

Section Reference 1: 2.1 A Brief Environmental History of the United States

Solution: 6 / 166 = 4%

3. In 1916, the U.S. had 13 national parks and 20 national monuments. Today there are 58 national parks and 73 national monuments. By what percent has the total of national parks and monuments increased in 90 years? a) 2.97% b) 75% c) 98% d) 297% Answer: d Difficulty: Hard Learning Objective 1: LO 2.1.0 List the contributions made by individuals during the environmental movement in the United States.

Learning Objective 2: LO 2.1.1 Briefly outline the environmental history of the United States.

Section Reference 1: 2.1 A Brief Environmental History of the United States 4. In 1968, Earth’s human population was ~3.5 billion; by 2008 it had grown to 6.7 billion.

By what percent did the population grow? a) 3% b) 46% c) 91% d) 96% Answer: c Difficulty: Hard Learning Objective 1: LO 2.1.0 List the contributions made by individuals during the environmental movement in the United States.

Learning Objective 2: LO 2.1.1 Briefly outline the environmental history of the United States.

Section Reference 1: 2.1 A Brief Environmental History of the United States

5. In 2007, the EPA considered that human exposure to contamination was under control at 93% of the 1,968 listed hazardous sites. How many sites still run the risk of human exposure to contamination? a) 212 b) 138 c) 47 d) the number of sites can’t be calculated with this information alone Answer: b Difficulty: easy

Learning Objective 1: LO 2.2.0 Evaluate the importance of the National Environmental Policy Act in protecting the environment.

Learning Objective 2: LO 2.2.1 Explain why the National Environmental Policy Act is the cornerstone of U.S. environmental law.

Section Reference 1: 2.2 U.S. Environmental Legislation Solution: 1,968 x .93 = 1,830 sites under control 1.968 – 1, 830 = 138 sites exposed to humans

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: 3

Question Type: Multiple Choice 1. The NPP for a particular river ecosystem is measured at 8,833 kcal/m2/year. Respiration by the aquatic producers in this ecosystem is estimated at 11,977 kcal/m2/year. Calculate the GPP for this ecosystem. a) -3,144 kcal/m2/year (a productivity deficit) b) 3,144 kcal/m2/year c) 20,810 kcal/m2/year d) it is impossible to calculate the GPP without other data Answer: c Difficulty: Medium Learning Objective 1: LO 3.3.0 Diagram how energy moves through an ecosystem.

Learning Objective 2: LO 3.3.4 Distinguish between gross primary productivity and net primary productivity, discussing human impact on the latter.

Section Reference 1: 3.3 The Flow of Energy Through Ecosystems

2. Assuming that 10,000 kcal of energy are theoretically available to the grass plant, how much useful energy will be available to the hawk in this food chain?

a) 1 kcal b) 10 kcal c) 100 kcal d) 1000 kcal Answer: B Difficulty: Medium Learning Objective 1: LO 3.3.0 Diagram how energy moves through an ecosystem.

Learning Objective 2: LO 3.3.4 Distinguish between gross primary productivity and net primary productivity, discussing human impact on the latter.

Section Reference 1: 3.3 The Flow of Energy Through Ecosystems 3. Use Figure 3.14, The Pyramid of Energy, to calculate what percent of energy (in Kcal/m2/yr) is available to a coyote that eats a rabbit.

a) 8% b) 10% c) 12% d) 17% Answer: a

Difficulty: Easy Learning Objective 1: LO 3.3.0 Diagram how energy moves through an ecosystem.

Learning Objective 2: LO 3.3.3 Describe typical pyramids of numbers, biomass, and energy.

Section Reference 1: 3.3 The Flow of Energy Through Ecosystems

4. Calculate how much more efficient swamps and marshes are in NPP compared to deserts and semidesert scrub ecosystems.

a) 12x more efficient b) 24x more efficient c) 36x more efficient d) 48x more efficient Answer: B Difficulty: Medium Learning Objective 1: LO 3.3.0 Diagram how energy moves through an ecosystem.

Learning Objective 2: LO 3.3.4 Distinguish between gross primary productivity and net primary productivity, discussing human impact on the latter.

Section Reference 1: 3.3 The Flow of Energy Through Ecosystems

5. How many carbon atoms are present in 6 molecules of glucose, the key product of photosynthesis? a) 6 b) 12 c) 18 d) 36 Answer: 36 Difficulty: Easy Learning Objective 1: LO 3.2.0 Discuss energy, work, and heat in terms of biological systems.

Learning Objective 2: LO 3.2.5 Write summary reactions for photosynthesis and cellular respiration, contrasting them.

Section Reference 1: 3.2 The Energy of Life

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: 4

Question Type: Multiple Choice 1. Convert the temperature range in the lower stratosphere (-450 C to -750 C) to degrees Fahrenheit. a) -49 to -1030 F b) -45 to -750 F c) -113 to -167 0 F d) can’t be calculated because the temperatures are below freezing Answer: c Difficulty: Medium Learning Objective 1: LO 4.3.0 Explain the various forces that affect Earth's atmosphere.

Learning Objective 2: LO 4.3.1 Describe the four layers of Earth’s atmosphere: troposphere, stratosphere, mesosphere, and thermosphere.

Section Reference 1: 4.3 The Atmosphere Solution: 0F = 0C x 9/5 + 32 0 F = -45 x 9/5 + 32 = -113 0F F = -75 x 9/5 + 32 = -167 0F

2. How much more water (in cubic kilometers) is lost from the oceans by evaporation than enters through precipitation and runoff?

a) 71,000 b) nearly 40,000 c) about 13,000 d) it is roughly the same, maintaining a fairly constant ocean level Answer: d Difficulty: Medium Learning Objective 1: LO 4.1.0 Diagram the main steps in the phosphorus, carbon, nitrogen, hydrologic, and sulfur biogeochemical cycles.

Section Reference 1: 4.1 The Cycling of Materials Within Ecosystems Solution: About 40,000 cubic kilometers of water enters oceans from land runoff and 385,000 from precipitation, thus maintaining a fairly constant ocean level.

3. Calculate how much more nitrogen is fixed by biological nitrogen fixation than by human activity.

a) 140 times as much b) 14 times as much c) 1.4 times as much d) this amount is impossible to calculate Answer: c

Difficulty: Medium Learning Objective 1: LO 4.1.0 Diagram the main steps in the phosphorus, carbon, nitrogen, hydrologic, and sulfur biogeochemical cycles.

Section Reference 1: 4.1 The Cycling of Materials Within Ecosystems Solution: Using human fixation of 100 (x 1012 g N), biological fixation is 140 (1.4 times as much)

4. Calculate how much incoming solar radiation is both absorbed and reflected by clouds.

a) 3% b) 9% c) 22% d) 31% Answer: c Difficulty: Easy Learning Objective 1: LO 4.2.0 Summarize how solar energy affects Earth's climate.

Section Reference 1: 4.2 Solar Radiation

5. Consider Earth's atmosphere from ground level to the outer limit of the thermosphere (~500km from the planetary surface). Which percent of the atmosphere is found within the troposphere?

a) 2% b) 7% c) 15% d) 32% Answer: a Difficulty: Medium Learning Objective 1: LO 4.3.0 Explain the various forces that affect Earth's atmosphere.

Learning Objective 2: LO 4.3.1 Describe the four layers of Earth’s atmosphere: troposphere, stratosphere, mesosphere, and thermosphere.

Section Reference 1: 4.3 The Atmosphere Solution: the troposphere (where life occurs) is only about 10km (10/500) thick.

Package Title: Chapter 10, Quantitative Course Title: Energy Consumption Chapter Number: 10

Question Type: Multiple Choice 1) Highly developed countries contain less than 20% of the world’s population but they consume _____ of the energy worldwide.

a) 20 b) 40 c) 60 d) 80 Answer: C Difficulty: Easy Learning Objective 1: LO 10.1.0 Describe global energy consumption.

Learning Objective 2: LO 10.1.2 Describe global energy use.

Section Reference 1: 10.1 Describe global energy consumption

2) All of the following are energy saving methods that can be incorporated into homes except

a) Installing programmable thermostats b) Eliminating energy vampires c) Installing low-flow shower heads d) Using incandescent bulbs Answer: D Difficulty: Medium Learning Objective 1: LO 10.2.0 List examples of where energy efficiency and conservation have been improved.

Learning Objective 2: LO 10.2.4 Identify methods of energy conservation both at home and in the workplace.

Section Reference 1: 10.2 Energy Efficiency and Conservation

3) Using batteries to store energy is an example of a) Kinetic energy storage b) Electrochemical energy storage c) Compressed air energy storage d) Superconducting magnetic energy storage

Answer: B Difficulty: Easy Learning Objective 1: LO 10.3.0 Discuss the advantages and disadvantages of electricity and hydrogen as sources of energy.

Learning Objective 2: LO 10.3.4 Describe the advantages and disadvantages of storing energy.

Section Reference 1: 10.3 Electricity, Hydrogen, and Energy Storage

4) Fuel consumption increases approximately ______ percent if a car is driven at 75 mph rather than 55 mph a) 15 b) 30 c) 50 d) 65 Answer: C Difficulty: Medium Learning Objective: LO 10.4.0 Describe the role policy decisions have in shaping energy resource and technology development.

Section Reference 1: 10.4 Energy Policy

5) Carbon in the form of CO2 is released into the atmosphere with the use of all of the following except a) Coal b) Natural gas c) Electricity d) Oil Answer: C Difficulty: Medium Learning Objective: LO 10.5.0 Discuss how sequestering carbon from fossil fuels could impact global climate.

Section Reference 1: 10.5 Energy and Climate Change: Carbon Sequestration and Electricity

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: 11

Question Type: Multiple Choice

1) Given: • Coal contains about 24 million Btu per ton, • Only about 40% of this energy can be converted into electricity • The average US household uses 108.7 Million BTU (31,857 kWh) per year • Coal produces about 2.71 tons carbon dioxide (CO2) per ton of coal How many tons of CO2 will be released each year to provide electricity for this household, if the electricity supply is entirely produced from coal? a) 50.40 tons of CO2 b) 40.11 tons of CO2 c) 30.68 tons of CO2 d) 11.32 tons of CO2 Answer: c Difficulty: Medium Learning Objective 1: LO 11.2.0 Discuss environmental and health issues associated with coal.

Learning Objective 2: LO 11.2.2 Summarize the environmental problems associated with using coal.

Section Reference 1: 11.2 Coal

2) In 2004, China used 6684 barrels of oil per day. This was 15.8% more than they used in 2003. If the rate of increase stays the same, how much total oil would they use in 2007? a) 10,379 barrels of oil per day b) 7740 barrels of oil per day c) 6699 barrels of oil per day d) 8963 barrels of oil per day Answer: a Difficulty: Medium Learning Objective 1: LO 11.5.0 Discuss how China's increasing energy demand is impacting global atmospheric emissions.

Learning Objective 2: 11.5 Energy and Climate Change: Fossil Fuels in China Section Reference: Solution: 6684 + (6684 * .158) = 7740 barrels of oil per day, 2005 7704 + (7704 * .158) = 8963 barrels of oil per day, 2006 8963 + (8963 * .158) = 10,379 barrels of oil per day, 2007

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3) A car consumes approximately 6530 BTU’s per person per mile compared to the bus which consumes 939 BTU’s per person per mile. How many times more energy efficient is it for you to take the bus to work than to drive your own car? a) 5 times b) 10 times c) 7 times d) 3 times Answer: c Difficulty: Easy Learning Objective 1: LO 11.3.0 Discuss environmental and health issues associated with oil and natural gas.

Learning Objective 2: LO 11.3.3 Discuss the environmental problems of using oil and natural gas.

Section Reference 1: 11.3 Oil and Natural Gas

4) Cars consume gasoline at certain efficiency; it has been shown that a car will get better fuel economy when driven at 55 mph compared to 75 mph. Fuel consumption can be increased by 50% when a car is driven at 75 mph rather that 55 mph. Considering that a car will get 20 (mpg) miles per gallon at 75 mph, on a trip of 300 miles how much less gas will be used if the car is driven at 55 mph. a) 15 gallons b) 10 gallons c) 5 gallons d) no difference Answer: c Difficulty: Medium Learning Objective 1: LO 11.3.0 Discuss environmental and health issues associated with oil and natural gas.

Learning Objective 2: LO 11.3.3 Discuss the environmental problems of using oil and natural gas.

Section Reference 1: 11.3 Oil and Natural Gas Solution: A trip of 300/20 = 15 gallons of gas at 75 mph 20 mpg X 50% divided by 100 = 10 mpg, 20 mpg + 10 mpg = 30 mpg at 55 mph 300/20 = 15 gallons of gas at 75 mpg 300/30 = 10 gallons of gas at 55 mph, 15 – 10 = 5 gallons

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Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number 12

Question Type: Multiple Choice

1) Given the following information determine how large of an area of photovoltaic cells will be necessary to power a house. The house uses 1000 kilowatt-hours (kWh) per month. It receives 6 kWh/m2/day of solar radiation. (m2 is square meter) The available photovoltaic cells have 15% efficiency. Assume perfect battery storage (0% losses) of the generated electricity. a) 166 m2 b) 66 m2 c) 40 m2 d) 37 m2 e) 5.6 m2 Answer: d Difficulty: Medium Learning Objective 1: LO 12.1.0 Compare and contrast active versus passive solar energy.

Learning Objective 2: LO 12.1.3 Contrast the advantages and disadvantages of solar thermal electric generation and photovoltaics in converting solar energy into electricity.

Section Reference 1: 12.1 Direct Solar Energy

2) Calculate the total amount of electricity (in MW) used globally in a year given the following information. Photovoltaic (PV) solar cells currently provide about 5000MW of electricity worldwide.

PV cells account for only about 0.15% of global electricity. a) 75,000 MW b) 7,500 MW c) 15,000MW d) 33,333MW e) 3,333MW Answer: d Difficulty: Medium Learning Objective 1: LO 12.1.0 Compare and contrast active versus passive solar energy.

Learning Objective 2: LO 12.1.3 Contrast the advantages and disadvantages of solar thermal electric generation and photovoltaics in converting solar energy into electricity.

Section Reference 1: 12.1 Direct Solar Energy

3) Uranium-235 (U-235) has an atomic mass of 235 and an atomic number of 92. What are the number of protons and neutrons in an atom of U-235?

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a) 92 protons and 92 neutrons b) 235 protons and 92 neutrons c) 92 protons and 235 neutrons d) 92 protons and 143 neutrons e) 143 protons and 92 neutrons Answer: d Difficulty: Easy Learning Objective 1: LO 12.4.0 Describe how nuclear power is used to produce energy.

Learning Objective 2: LO 12.4.1 Distinguish between nuclear energy and chemical energy.

Section Reference 1: 12.4 Nuclear Power

4) Starting with 1 kg of Plutonium-239, which has a half-life of approximately 24,000 years, how many grams will remain after 24,000 years? How many will remain after 96,000 years? a) 500 grams and 62.5 grams b) 1000 grams and 125 grams c) 500 grams and 0 grams d) 0 grams and 0 grams e) 500 grams and 250 grams Answer: a Difficulty: Easy Learning Objective 1: LO 12.4.0 Describe how nuclear power is used to produce energy.

Learning Objective 2: LO 12.4.1 Distinguish between nuclear energy and chemical energy.

Section Reference 1: 12.4 Nuclear Power

5) The Yucca Mountain high level Nuclear Waste Storage Facility has a design capacity of 70,000 metric tons of radioactive waste and is designed to last to the year 2025. In 2000 the United States had an estimated 42,710 metric tons. Approximately how many metric tons per year of high level radioactive waste can be generated in the United States without exceeding the design capacity? a) 1,000 b) 500 c) 100 d) 10,000 e) 10 Answer: a Difficulty: Easy Learning Objective 1: LO 12.4.0 Describe how nuclear power is used to produce energy.

Learning Objective 2: LO 12.4.1 Distinguish between nuclear energy and chemical energy.

Section Reference 1: 12.4 Nuclear Power 2

6). Uranium ore is a mixture of isotopes of which 0.71% is U-235. How much uranium ore must be mined to obtain one ton of fuel grade U-235 at 3% enrichment? a) 20 b) 42 c) 50 d) 2.1 e) 7 Answer: B Difficulty: Easy Learning Objective 1: LO 12.4.0 Describe how nuclear power is used to produce energy.

Learning Objective 2: LO 12.4.1 Distinguish between nuclear energy and chemical energy.

Section Reference 1: 12.4 Nuclear Power

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Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: 13

Question Type: Multiple Choice

1) Calculate how many gallons of water are wasted each year from a leak of one drop per second (13,140 drops equals 1 gallon). a) 1 gallon b) 360 gallons c) 2400 gallons d) 13,140 gallons e) 31,536,000 gallons Answer: c Difficulty: Easy Learning Objective 1: LO 13.6.0 Examine methods of water conservation.

Learning Objective 2: LO 13.6.1 Give examples of water conservation by agriculture, industry, and individual homes and buildings.

Section Reference 1: 13.6 Water Conservation

2) At a particular site, the ocean water used for desalination has a salinity of 35 ppt (parts per thousand). If the desalinization removes all salt from water, how many grams of salt will be removed in the process of producing 100 liters of fresh water?

1 liter of fresh water weighs 1 kg; ppt = weight of solute / weight of solution * 1000; note that the weight of the solute is included in the weight of the solution. a) 100 kg b) 42 kg c) 36.3 kg d) 3.63 kg e) 3.63 g Answer: d Difficulty: Difficult Learning Objective 1: LO 13.5.0 Discuss how water management is used to provide sustainable water supplies.

Learning Objective 2: LO 13.5.4 Briefly describe two methods of desalinization.

Section Reference 1: 13.5 Water Management

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3) The 1922 Colorado River Compact stipulates an annual allotment of 7.5 million acre-feet of water to the lower Colorado (California, Nevada, Arizona, and New Mexico). An acre-foot equals approximately 326,000 gallons of water. If the standard adequate daily requirement of water is 5.2 gallons per person per day, approximately how many people can this allotment provide for on a daily basis? Approximately, how many people can it provide for if typical American water consumption is 90 gallons per day? a) 1.29 billion, 7.44 billion b) 1.29 billion, 7.44 million c) 1.29 billion, 74.4 million d) 129 million, 74.4 million e) 12.9 million, 7.44 million Answer: c Difficulty: Medium Learning Objective 1: LO 13.3.0 Examine water problems in the United States.

Section Reference 1: 13.3 Water Problems in the United States and Canada Solution: 7,500,000 million acre-feet * 326,000 gallons = 2,445,000,000,000 gallons / 365 days = 6,698,630,137 gallons/day Standard water consumption: 6,698,630,137 gallons per day / 5.2 gallons per person per day = 1,288,198,103 people = 1.29 billion people Typical American water consumption: 6,698,630,137 gallons per day / 90 gallons per person per day = 74,429,224 people = 74.4 million people

5) Today, ultra low flush toilets are being sold that only use 1.6 gallons per flush. Most post1980 toilet models use 3.5 gallons per flush. Calculate the annual percent reduction in toilet water use for a family of four if a typical family member flushes 4 times per day. a) 56.2% b) 25.6% c) 54.3% d) 36.5% e) none of these choices is correct Answer: c Difficulty: Easy Learning Objective 1: LO 13.6.0 Examine methods of water conservation.

Learning Objective 2: LO 13.6.1 Give examples of water conservation by agriculture, industry, and individual homes and buildings.

Section Reference 1: 13.6 Water Conservation

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Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: 14

Question Type: Multiple Choice

1.) If soil loss from erosion is 2.5 cm over 20 years in a particular region and if 1 mm of topsoil in an land area of 1 hectare weighs 13.0 metric tons, how many metric tons of topsoil will be loss per hectare in 20 years in that region. a) 2.5 metric tons b) 32.5 metric tons c) 260 metric tons d) 325 metric tons e) 650 metric tons Answer: d Difficulty: Easy Learning Objective 1: LO 14.3.0 Identify environmental soil problems.

Learning Objective 2: LO 14.3.2 Explain the impacts of soil erosion, mineral depletion, soil salinization, and desertification on plant growth.

Section Reference 1: 14.3 Environmental Problems Related to Soil

2) If the rate of soil formation is 1 metric tons/hectare/year, how long will take to replace 2 cm of soil, given that 1 mm/hectare of soil weighs 13 metric tons. a) 13 years b) 26 years c) 260 years d) 1300 years e) 2600 years Answer: c Difficulty: Easy Learning Objective 1: LO 14.1.0 Describe the soil ecosystem.

Learning Objective 2: LO 14.1.2 Identify the factors involved in the formation of the soil system.

Section Reference 1: 14.1 The Soil System

3) If you examined 100 lbs of soil, approximately how many pounds would be mineral particles, organic materials, water and air? a) 45-5-25-25 lbs respectively

b) 25-25-5-45 lbs respectively c) 30-10-30-30 lbs respectively d) these amounts are impossible to calculate without additional information Answer: a Difficulty: Easy Learning Objective 1: LO 14.1.0 Describe the soil ecosystem.

Learning Objective 2: LO 14.1.2 Identify the factors involved in the formation of the soil system.

Section Reference 1: 14.1 The Soil System

4) If the largest sand particles are about 2mm in diameter, how much larger are they than the largest particles of silt (0.05mm in diameter)? a) 0.1x as large b) 10x as large c) 25x as large d) 40x as large Answer: d Difficulty: Easy L.O. Discuss physical and chemical properties of soil.

Learning Objective 1: LO 14.2.0 Discuss physical and chemical properties of soil.

Learning Objective 2: LO 14.2.1 Briefly describe soil texture and soil acidity.

Section Reference 1: 14.2 Soil Properties and Major Soil Types

5) If approximately 2.5 cm of soil on average is lost by erosion in the U.S. within a twenty year period, how much soil is lost each year? a) 0.13cm b) 0.5cm c) 13cm d) 50cm Answer: a Difficulty: Easy Learning Objective 1: LO 14.3.0 Identify environmental soil problems.

Learning Objective 2: LO 14.3.2 Explain the impacts of soil erosion, mineral depletion, soil salinization, and desertification on plant growth.

Section Reference 1: 14.3 Environmental Problems Related to Soil

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 15

Question Type: Multiple Choice

1) If North America consumes approximately 7,300,000 metric tons of aluminum per year and this represents approximately 29% of global aluminum consumption, how much aluminum does the world consume annually? a) 57,631,238 tons b) 49,369,126 tons c) 35,763,029 tons d) 25,172,413 metric tons Answer: d Difficulty: Medium Learning Objective 1: LO 15.3.0 Compare and contrast mineral use between developed and developing countries.

Learning Objective 2: LO 15.3.1 Contrast the consumption of minerals by developing countries and by industrialized countries such as the United States and Canada.

Section Reference 1: 15.3 Minerals: An International Perspective Solution: 7,300,000 / 29 = x / 100 29x = 730,000,000 x = 730,000,000 / 29 x = 25,172,413 metric tons

2) If Thiobacillus bacteria allows a 90% rate of recovery of gold from low grade ores compared to 75% recovery from tradition methods, how much more efficient is the bacteria? a) 12% b) 15% c) 75% d) 83% Answer: b Difficulty: Medium Learning Objective 1: LO 15.4.0 Examine methods of increasing the supply of minerals worldwide.

Section Reference 1: 15.4 Increasing the Supply of Minerals Solution: 90%-75% = 15%

[insert table 15.2]

3) If 10 tons of iron ore are mined in Montana, how many tons of pure iron can actually be extracted?

a) 10 b) 6 c) 4 d) 2 Answer: c Difficulty: Easy Learning Objective 1: LO 15.2.0 Discuss the environmental impacts of mining.

Learning Objective 2: LO 15.2.1 Explain the environmental impacts of mining and refining minerals, including a brief description of acid mine drainage.

Section Reference 1: 15.2 Environmental Impacts Associated with Minerals Solution: 6 tons (60%) of iron ore becomes waste tailings, leaving 4 tons of useful iron.

[insert figure 15.8] 4) Estimate what percent of the world's gold supply is consumed by the U.S. and Canada.

a) 4% b) 9% c) 11% d) 13% Answer: b Difficulty: Easy Learning Objective 1: LO 15.3.0 Compare and contrast mineral use between developed and developing countries.

Learning Objective 2: LO 15.3.1 Contrast the consumption of minerals by developing countries and by industrialized countries such as the United States and Canada.

Section Reference 1: 15.3 Minerals: An International Perspective Solution: Use the bar graph to estimate the percentage.

5) Given that there are 128 fluid ounces in one gallon of liquid, and recycling one aluminum can saves the energy equivalent of about 6 ounces of gasoline, how many aluminum cans would need to be recycled to save the energy equivalent of one gallon of gasoline? a) 22 cans b) 47 cans c) 768 cans d) impossible to calculate with only this data Answer: a Difficulty: Easy

Learning Objective 1: LO 15.5.0 Identify ways to conserve and increase mineral supplies.

Learning Objective 2: LO 15.5.1 Summarize the conservation of minerals by reuse, recycling, and changing our mineral requirements.

Section Reference 1: 15.5 Using Substitution and Conservation to Expand Mineral Supplies Solution: 128/6 = 21.3 cans so round up to 22

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 16

Question Type: Multiple Choice

1) Annual global trade in animals is conservatively estimated at $10 billion. One third of that trade is illegal because it involves rare or endangered species. Calculate how much illegal trade, in millions of dollars, is done each day. a) $11.78 million b) $9.04 million c) $6.25 million d) $3.33 million Answer: b Difficulty: Medium Learning Objective 1: LO 16.2.0 Discuss the major causes of extinction.

Learning Objective 2: LO 16.2.5 Describe four human causes of species endangerment and extinction, telling which cause is the most important.

Section Reference 1: 16.2 Extinction and Species Endangerment Solution: $10 billion x 0.33 = $3.3 billion/year 3,300,000,000 / 365 days = $9.04 million / day

2) High concentrations of endemic species live on island nations, such as the Philippines and Madagascar. Presently each of these countries has only set aside less than 2% of their total land for protection. If the total land area of the Philippines and Madagascar is 300,000 km2 and 581,540 km2 respectively, what is the total area set aside for protection of endemic species on these two islands? a) 5,630.8 km2 b) 17,630.8 km2 c) 11,630.8 km2 d) none of these choices is correct Answer: b Difficulty: Easy Learning Objective 1: LO 16.2.0 Discuss the major causes of extinction.

Learning Objective 2: LO 16.2.4 Define biodiversity hotspots, explaining where most of the world’s biodiversity hotspots are located.

Section Reference 1: 16.2 Extinction and Species Endangerment Solution: 0.02 * (300,000 km2 + 581,540 km2) = 17,630.8 km2 3) Worldwide, 11.5% of Earth’s total land area (19 million km2) has been set aside to protect

biological diversity. How much land remains unprotected? a) 2,185,000 km2 b) 13,300,000 km2 c) 16,815,000 km2 d) none of these choices is correct Answer: c Difficulty: Easy Learning Objective 1: LO 16.3.0 Describe conservation biology.

Learning Objective 2: LO 16.3.1 Define conservation biology, comparing in situ and ex situ conservation.

Section Reference 1: 16.3 Conservation Biology Solution: 19,000,000 km2 * (1 - .115) = 16,815,000 km2

4) In late 2006, there were a total of 373 endangered whooping cranes in the wild plus a total of 145 captive cranes that scientists had successfully breed in captivity. If scientists are able to successfully introduce approximately 70% of the captive population into the wild population, how many whooping cranes will exist in the wild? a) 101 b) 272 c) 475 d) none of these choices is correct Answer: c Difficulty: Medium Learning Objective 1: LO 16.5.0 Distinguish between conservation biology and wildlife management.

Section Reference 1: 16.5 Wildlife Management Solution: (145 * 0.70) + 373 = 474.5 = 475

5) According to the Global Amphibian Assessment, 168 amphibian species have gone extinct in the world over the last 2 decades. Given this information, on average, how many amphibian species go extinct each month? a) 8.4 b) 1.7 c) 1 d) none of these choices is correct Answer: c Response: Difficulty: Medium Learning Objective 1: LO 16.2.0 Discuss the major causes of extinction.

Learning Objective 2: LO 16.2.2 Contrast threatened and endangered species.

Section Reference 1: 16.2 Extinction and Species Endangerment Solution: (168 species / 20 years) * (1 yr / 12 months) = 0.7 ~ 1 species/month

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 17

Question Type: Multiple Choice

1) Excluding agriculture, only about 3 % of the Earth's total surface area (14.9 billion hectares) is settled (homes, roads, cities, etc.). What is this settled area in hectares? a) 4.47 million hectares b) 44.7 million hectares c) 447 million hectares d) 4.47 billion hectares e) 44.7 billion hectares Answer: c Difficulty: Easy Learning Objective 1: LO 17.1.0 Identify services that are provided by ecosystems.

Learning Objective 2: LO 17.1.2 Describe world land use.

Section Reference 1: 17.1 Land Use Solution: .03 * 14.9 billion hectares = .447 billion hectares = 447 million hectares

2) In 2003, the BLM collected $12,788,353 in grazing fees at a rate of $1.35 per head. The average private grazing fee was approximately $11.00 per head. How much more money could the BLM have collected if they increased their grazing fee to 1/2 of the private fee? (Round to the nearest head and to the nearest dollar). a) $104,201,394 b) $6,394,177 c) $70,335,942 d) $52,100,697 e) $39,312,344 Answer: e Difficulty: Medium Learning Objective 1: LO 17.4.0 Describe how human activity is impacting rangeland and agricultural lands.

Learning Objective 2: LO 17.4.1 Describe public rangelands and current issues of concern.

Section Reference 1: 17.4 Rangelands and Agricultural Lands Solution: ($12,788,353 / $1.35/head) * [($11.00/head / 2) - $1.35/head] = $39,312,344

3.) The NPS, USFS, FWS, and BLM oversee 630 wilderness areas that encompass 40.3 million hectares of land. Given that 1 hectare = 2.47105 acres, what is the average size of each wilderness area in acres? a) 160,000 acres b) 1.6 million acres c) 16.0 million acres d) 68.9 million acres e) 6.89 million acres Answer: a Difficulty: Medium Learning Objective 1: LO 17.2.0 Examine the purpose for creating wilderness, parks, and wildlife refuges.

Section Reference 1: 17.2 Wilderness, Parks, and Wildlife Refuges Solution: (40.3 million hectares * 2.471 acres/hectare) / 630 = 0.158068 = 0.16 million acres 4) Calculate the total land area (in km2) held by Native American tribes if the total land area for the U.S. is 9,631,420 km2 and 3% of it is owned by Native Americans. Do the same for land held by the federal government (they own 35% of the land in the U.S.). a) 288,943 km2; 3,370 km2 b) 288,943 km2; 3,370,997 km2 c) 2,889 km2; 3,370,997 km2 d) 288,943 km2; 370,997 km2 e) none of these choices is correct Answer: b Difficulty: Easy Learning Objective 1: LO 17.1.0 Identify services that are provided by ecosystems.

Learning Objective 2: LO 17.1.3 Describe land use in the United States.

Section Reference 1: 17.1 Land Use Solution: 9,631,420 km2 * 0.03 = 288,942.6 = 288,943 km2 9,631,420 km2 * 0.35 = 3,370,997 km2

5) Park Service entrance fees bring in nearly $132 million dollars per year. It is estimated that the Park Service spends nearly 2.2 billion dollars a year on upgrades and park maintenance. What percentage of upgrades and maintenance is provided for by entrance fees? a) 16% b) 1.6% c) 0.6% d) 0.06% e) none of these

Answer: e Difficulty: Medium Learning Objective 1: LO 17.2.0 Examine the purpose for creating wilderness, parks, and wildlife refuges.

Section Reference 1: 17.2 Wilderness, Parks, and Wildlife Refuges Solution: 100 * ($132 x 106 / $2.2 x 109) = 6 %

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 18

Question Type: Multiple Choice

1) It takes 7 kg of livestock grain (i.e., corn) to produce 1 kg of beef, 6 kg of livestock grain to produce 1 kg of pork and 2.7 kg of livestock grain to produce 1 kg of poultry. If the grain you are feeding your livestock costs $150/ton, calculate how much it costs to produce 1 kg of each type of meat. (1 ton = 907.2 kg). a) $1.16/kg beef, $0.99/kg pork, $0.45/kg poultry b) $42.346/kg beef, $36.29/kg pork, $16.33/kg poultry c) $0.024/kg beef, $0.028/kg pork, $0.06/kg poultry d) $21.43/kg beef, $25.00/kg pork, $55.56/kg poultry Answer: a Difficulty: Medium Learning Objective 1: LO 18.1.0 Discuss the current issues associated with global food security.

Learning Objective 2: LO 18.1.2 Define world grain stocks, explaining how they are a measure of world food security.

Section Reference 1: 18.1 World Food Security Solution: $150/ton divided by 907.2 kg/ton = $0.165 / kg (approximate) 7 kg/1 kg beef * $0.165/kg = $1.16/kg beef 6 kg/1 kg pork * $0.165/kg = $0.99/kg pork 2.7 kg/1 kg poultry * $0.165/kg = $0.45/kg poultry

2) Given the following data, calculate the percent increase or decrease in tons per hectare of world grain production between 1970 and 2001. 1970: 663 million hectares farmed, 1,079 million tons produced. 2001: 684 million hectares farmed, 1,843 million tons produced (round results to nearest percent). a) 59% increase b) 66% increase c) 97% increase d) 59% decrease e) 66% decrease Answer: b Difficulty: Hard Learning Objective 1: LO 18.1.0 Discuss the current issues associated with global food security.

Learning Objective 2: LO 18.1.2 Define world grain stocks, explaining how they are a measure of world food security.

Section Reference 1: 18.1 World Food Security Solution: 1970 tons per hectare = 1,079 million tons / 663 million hectares = 1.627 tons/hectare (approximate) 2001 tons per hectare = 1,843 million tons / 684 million hectares = 2.694 tons/hectare (approximate) Difference 2.694 tons/hectare – 1.626 tons/hectare = 1.068 tons/hectare % Difference = 1.068 tons/hectare divided by 1.627 tons/hectare = .6564 = 65.64%

3) The average adult man requires 3000 kcal per day, whereas the average adult woman requires 2200 kcal per day. Given this information, a man requires _____ more calories per year than a woman. a) 2.67% b) 8.21% c) 36.3% d) 73% e) none of these choices is correct Answer: c Difficulty: Easy Learning Objective 1: LO 18.2.0 Explain global food production.

Learning Objective 2: LO 18.2.2 Explain why having just three plant species to provide almost half of the calories people consume is a potential problem.

Section Reference 1: 18.2 Food Production Solution: 100 * (3000 - 2200) / 2200 = 36.36%

4) Average world grain production increased from 247 kg per person in 1950 to 342 kg per person in 1984. Given this information, calculate the average increase per year from 1950 to 1984. a) 27.8% b) 1.13% c) 38.5% d) 8.2% e) none of these choices is correct Answer: b Difficulty: Medium Learning Objective 1: LO 18.1.0 Discuss the current issues associated with global food security.

Learning Objective 2: LO 18.1.2 Define world grain stocks, explaining how they are a measure of world food security.

Section Reference 1: 18.1 World Food Security Solution: 100 * (342 kg/person – 247 kg/person) / 247 kg/person = 38.46% / 34years = 1.13 % per year

5) During the green revolution in Mexico, the annual amount of wheat produced per hectare increased from approximately 700kg annually in 1920 to 2400 kg per hectare in 1965. Calculate the percent increase in annual wheat production during the green revolution. a) .05% b) .54% c) 5.4% d) 54% e) none of these Answer: c Difficulty: Medium Learning Objective 1: LO 18.3.0 Identify the major challenges with increasing global crop and livestock production.

Learning Objective 2: LO 18.3.2 Describe the benefits and problems associated with the green revolution.

Section Reference 1: 18.3 Challenges of Producing More Crops and Livestock Solution: 100 * (2400 kg – 700 kg) / 700 kg = 242.857% increase / 45 years = 5.3968 = 5.4%

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 19

Question Type: Multiple Choice

1) Given the following data about Houston, Texas, calculate how many days per year its residents experienced good air quality, and how many days per year they experienced unhealthful air quality.

Data: days with good air quality: 48%; days with moderate air quality: 41%; days with unhealthful air quality: 4%. a) 17520 days good air quality, 1460 days unhealthy air quality b) 175.2 days good air quality, 14.6 days unhealthy air quality c) 48.0 days good air quality, 4.0 days unhealthy air quality d) 17.5 days good air quality, 1.4 days unhealthy air quality e) 7.6 days good air quality, 91.25 days unhealthy air quality Answer: b Difficulty: Easy Learning Objective 1: LO 19.4.0 Discuss how air pollution is controlled and regulated in the U.S. Learning Objective 2: LO 19.4.2 Summarize the effects of the Clean Air Act on U.S. air pollution.

Section Reference 1: 19.4 Controlling Air Pollution in the United States Solution: 365 days per year * 48% good air quality = 365 * .48 = 175.2 days 365 days per year * 4% good air quality = 365 * .04 = 14.6 days

2) Given the following data about the emission of nitrogen oxides in China, calculate the percent change from 1990 to 1995.

Data: 1990: 8,712.71 thousand metric tons per year; 1995: 12,357.03 thousand metric tons per year. Round to two decimal places. a) 141.83 % b) 70.51 % c) 41.83 % d) 36.44 % e) 29.49 % Answer: c Difficulty: Medium

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Learning Objective 1: LO 19.7.0 Compare and contrast air pollution in developing and developed countries.

Learning Objective 2: LO 19.7.1 Explain why air pollution is generally worse in developing countries than in highly developed countries.

Section Reference 1: 19.7 Air Pollution Around the World Solution: 12,357.03 – 8712.71 = 3644.32 thousand metric tons per year change 3644.32 / 8712.71 = 0.418276 .418276 * 100 = 41.8276 % = 41.83 % change 3) Due to rapid industrialization in urban areas, China currently exhibits the worst air quality in the world. In 2004, an estimated 400,000 premature deaths were associated with air pollution.

Given China’s population of over 1,300,000,000 people, calculate the approximate percentage of the population that has died as a result of air pollution. a) .0004% b) .004% c) .04% d) 4% e) none of these choices is correct Answer: c Difficulty: Easy Learning Objective 1: LO 19.7.0 Compare and contrast air pollution in developing and developed countries.

Learning Objective 2: LO 19.7.1 Explain why air pollution is generally worse in developing countries than in highly developed countries.

Section Reference 1: 19.7 Air Pollution Around the World Solution: 400,000 deaths/1,300,000,000 people = 0.00037 * 100 = 0.04%

4) Mexico City has seen dramatic human population growth this century. Its overall growth has increased from 5.4 million in 1960 to 18.7 million in 2003. Calculate the percent increase, per year, for this 43 year period. a) 0.5% b) 15% c) 150% d) 32.6% e) none of these choices is correct Answer: a Difficulty: Medium Learning Objective 1: LO 19.7.0 Compare and contrast air pollution in developing and developed countries.

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Learning Objective 2: LO 19.7.1 Explain why air pollution is generally worse in developing countries than in highly developed countries.

Section Reference 1: 19.7 Air Pollution Around the World Solution: 18.7 million – 5.4 million = 13.3 million 100* 13.3 million/5.4 million = 246% increase in population 246% / 43 years = 0.5 % increase in population per year

5) Each year in the United States, more than 154 million metric tons of pollutants are emitted into the air. Calculate (in kg) the amount of pollutants emitted per day and per hour. a) 42.19 kg/day, 1.75 kg/hour b) 42.19 kg/day, 17.58 kg/hour c) 421.92 kg/day, 1.75 kg/hour d) 421.92 kg/day, 17.58 kg/hour e) none of these choices is correct Answer: d Difficulty: Hard Learning Objective 1: LO 19.2.0 Identify the major types of air pollutants.

Learning Objective 2: LO 19.2.2 List various sources of outdoor air pollution.

Section Reference 1: 19.2 Types and Sources of Air Pollution Solution: 154 metric tons * 1000kg/ton = 154,000 kg 154,000 kg / 365 days = 421.92 kg/day 421.92 kg/day / 24 hours/day = 17.58 kg/hour

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Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 20: Global Climate Change

Question Type: Multiple Choice

[insert table 20.1] 1. Identify which of the listed atmospheric gases has increased the most since preindustrial times (watch your units).

a) carbon dioxide b) methane c) nitrous oxide d) CFC -11 Answer: a Difficulty: Medium

Learning Objective 1: LO 20.1.0 Explain the causes of climate change.

Learning Objective 2: LO 20.1.1 Explain radiative forcing, greenhouse gases, and the enhanced greenhouse effect.

Section Reference 1: 20.1 Introduction to Climate Change Solution: While CFC – 11 has increased 245% since preindustrial times, the concentration is measured in parts per trillion. Therefore, this amount is still less than the nearly 112% increase in methane when measured in parts per billion, and the 36% increase in carbon dioxide measured in parts per million. The 36% increase in carbon dioxide is the most significant, when measured in parts per million.

2) What has been the percent change in increasing atmospheric carbon dioxide concentration from before the Industrial Revolution (about 200 years ago) when it was about 288 parts per million (ppm) to 2010 when it averaged 386 ppm? Round to the nearest percentage. a) 23 % b) 34 % c) 71 % d) 88 % e) 130 % Answer: b Difficulty: Easy Learning Objective 1: LO 20.1.0 Explain the causes of climate change.

Learning Objective 2: LO 20.1.1 Explain radiative forcing, greenhouse gases, and the enhanced greenhouse effect.

Section Reference 1: 20.1 Introduction to Climate Change Solution: 386 ppm – 288 ppm = 98 ppm change 98 ppm / 288 ppm = 0.34 0.34* 100 = 34 % change

[insert figure 20.1] 3) Calculate the overall change in mean annual global temperature from 1960-2010 (in degrees Centrigrade)

a) 0.5 b) 0.6 c) 0.8 d) 1.5 Answer: c Difficulty: Easy Learning Objective 1: LO 20.1.0 Explain the causes of climate change.

Learning Objective 2: LO 20.1.3 Explain how climate models project future climate conditions.

Section Reference 1: 20.1 Introduction to Climate Change

[insert figure 20.2] 4) Identify the approximate year with the least seasonal variation in atmospheric carbon dioxide concentrations.

a) 1977 b) 1981 c) 1991 d) 1995 Answer: d Difficulty: Easy Learning Objective 1: LO 20.1.0 Explain the causes of climate change.

Learning Objective 2: LO 20.1.3 Explain how climate models project future climate conditions.

Section Reference 1: 20.1 Introduction to Climate Change Solution: Look for the least with the least variation in the curve of winter and summer carbon

dioxide levels.

5.) One piece of evidence for global climate change is that phenological Spring in the Northern Hemisphere arrived about six days earlier in 2006 than in 1959, and phenological Autumn arrived about 5 days later for the same time period. What is the net change in the length of seasons? a) Spring (+6) + Autumn (+5) = +11 days b) Spring (+6) – Autumn (-5) = +1 day c) Autumn (-5) + Spring (-6) = -11 days d) impossible to calculate with only this data Answer: a Difficulty: Easy Learning Objective 1: LO 20.1.0 Explain the causes of climate change.

Learning Objective 2: LO 20.1.3 Explain how climate models project future climate conditions.

Section Reference 1: 20.1 Introduction to Climate Change Solution: Add 6 days to Spring and 5 days to Summer = 11 days

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 21

Question Type: Multiple Choice

1) The water pollution from a slaughterhouse, in which one ton of cattle was processed each day, produced a daily biochemical oxygen demand (BOD) of 10.5 kg? Calculate the human population equivalent (how many people) that it would take to produce the same daily BOD as this slaughterhouse. Each person produces an average of 0.07 kg of BOD per day. a) 1 b) 11 c) 15 d) 150 e) 1,500 Answer: d Difficulty: Easy Learning Objective 1: LO 21.2.0 Identify sources of water pollution.

Learning Objective 2: LO 21.2.2 Provide examples of agricultural, municipal, and industrial water pollution.

Section Reference 1: 21.2 Water Quality Today Solution: 10.5 kg BOD/day divided by 0.07 kg BOD/day/person = 150 persons

2) An asphalt parking lot measures 100 m by 500 m. Calculate how much storm water runoff, in gallons, will be created following a storm which produced 2 cm of rain. Conversion factors 1 cubic meter (m3) = 1000 liters, 1 gallon = 3.79 liters (approx). Round to the nearest gallon. a) 2,274 gallons b) 50,000 gallons c) 158,316 gallons d) 263,852 gallons e) 26,385,224 gallons Answer: d Difficulty: Hard Learning Objective 1: LO 21.2.0 Identify sources of water pollution.

Learning Objective 2: LO 21.2.2 Provide examples of agricultural, municipal, and industrial water pollution.

Section Reference 1: 21.2 Water Quality Today

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Solution: volume = 100 m * 500 m * 0.02 m = 1,000 m3 {1,000 m3 * 1000 liters/ m3} / 3.79 liters/gal = 263,852 gallons

3) In 1998, the U.S. Environmental Protection Agency (EPA) evaluated data from 1,368 U.S. watersheds. They found that sediments in 7% of watersheds are so contaminated, that consuming fish from these watersheds would potentially threaten human health. Calculate the total number of contaminated watersheds. a) 1,464 b) 1,272 c) 957 d) 9 e) none of these choices is correct Answer: e Difficulty: Easy Learning Objective 1: LO 21.1.0 Identify the major categories of water pollutants.

Learning Objective 2: LO 21.1.1 Briefly describe eight categories of water pollutants.

Section Reference 1: 21.1 Types of Water Pollution Solution: 1368 watersheds * 0.07 = 95.76 4) Leaking underground petroleum storage tanks are a common pollutant to the nation’s groundwater. Despite laws to the contrary, there are an estimated 250,000 underground storage tanks that may be leaking at service stations in the United States. On average, cleanup of these leaking gas tanks can cost $500,000 per tank. Calculate the approximate cost per person (given that the current U.S population is 311,706,602 people) if we were to cleanup all potential leaking tanks this year. a) $401.01 b) $824 c) $1.13 d) $41.87 e) none of these Answer: a Difficulty: Medium Learning Objective 1: LO 21.2.0 Identify sources of water pollution.

Learning Objective 2: LO 21.2.1 Contrast point source pollution and nonpoint source pollution.

Section Reference 1: 21.2 Water Quality Today Solution: (250,000 tanks * $500,000) / 311,706,602 U.S. population = $ 401.01 per person

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5) Wastewater requires several treatments to prevent environmental and public health problems.

Nationwide, 11% of the U.S. population has access to primary treatment only, 62% have access to both primary and secondary treatments, and 27% have access to primary, secondary and tertiary treatments. Given that the current U.S. population is approximately 303.5 million people, calculate approximately how many more people have access to all three forms of wastewater treatment versus primary treatment only. a) 485,000 b) 48.5 million c) 81.9 million d) 33.4 million e) none of these Answer: b Difficulty: Easy Learning Objective 1: LO 21.3.0 Describe methods to improve water quality.

Learning Objective 2: LO 21.3.3 Distinguish among primary, secondary, and tertiary treatments for wastewater.

Section Reference 1: 21.3 Improving Water Quality Solution: (0.27 - 0.11) * 303.5 m people = 48.56 million

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Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 22

Question Type: Multiple Choice

1) A water sample was analyzed and found to contain .00005 ppm of DDT. Plankton living in the same water sample were found to contain 800 times the concentration of DDT. In ppm, what was the concentration of DDT in the plankton? a) .00000000625 ppm b) 0.016 ppm c) 0.04 ppm d) 0.16 ppm e) 0.4 ppm Answer: c Difficulty: Easy Learning Objective 1: LO 22.2.0 Discuss the benefits and problems associated with the use of pesticides.

Learning Objective 2: LO 22.2.3 Summarize the problems associated with pesticide use.

Section Reference: 22.2 Benefits and Problems with Pesticides Solution: 0.00005 ppm * 800 = 0.04 ppm

2) The Food and Agriculture Organization of the United Nations estimates that world consumption of herbicides was 543,776 metric tons in 1997 and 201,182 metric tons in 2001.

What was the average annual percent change in consumption? a) -15.75% / year b) 42.57% / year c) -63% / year d) -9.25% / year e) 37% / year Answer: a Difficulty: Medium Learning Objective 1: LO 22.6.0 Discuss issues associated with the production and use of banned pesticides.

Section Reference: 22.6 The Manufacture and Use of Banned Pesticides Solution: 100 * (201,182 – 543,776 metric tons) / 543,776 metric tons = -63 % 2001 – 1997 = 4 years, -63% / 4 yrs = -15.75% / year

3) According to the U.S. Geological Survey, it is estimated that nearly 150 million pounds of pesticides are applied to crops in the Central Valley of California each year. Total land area of California is 163,707 square miles. Approximately how many pounds of pesticides per square mile are applied to California lands per year? a) 916 lbs/mi2 b) 9.16 lbs/mi2 c) 91.6 lbs/mi2 d) 916 kg/mi2 e) none of these choices is correct Answer: a Difficulty: Easy Learning Objective 1: LO 22.2.0 Discuss the benefits and problems associated with the use of pesticides.

Learning Objective 2: LO 22.2.4 Describe the pesticide treadmill, explaining how resistance management may help with this problem.

Section Reference: 22.2 Benefits and Problems with Pesticides

4) Reproductive controls of pests are often used as alternative to pesticides. The sterile male technique, often used to control medfly populations, is currently employed in California. Aerial drops of 1.5 million sterile male medflies were made twice a week over a 12.2 mi2 area from mid September 2007 until the end of July 2008. Calculate how many total medflies were released and approximately how many medflies were applied per square mile throughout the duration of this project. a) 126 thousand, 10 million/mi2 b) 1.26 million, 1.0 million/mi2 c) 12.6 million, 1.0 million/mi2 d) 126 million, 10 million/mi2 e) none of these Answer: d Difficulty: Medium Learning Objective 1: LO 22.4.0 List methods other than the use of pesticides to control pests.

Section Reference: 22.4 Alternatives to Pesticides Solution: Time interval = 10.5 months: (10.5 months) (4 weeks/month) (2 drops/week) = 84 drops 84 drops * 1.5 million medflies/drop = 126 million medflies 126 million medflies / 12.2 mi2 = 10.3 million medflies/mi2

5) The United States imports nearly 1.2 million shipments of food annually from other countries.

The FDA monitors toxic residues on incoming fruits and vegetables, but only inspects about 1% of the food shipments that enter each year. Assuming the U.S. imports 50 million metric tons of fruits and vegetables a year, calculate how many pounds of produce is not being inspected for traces of pesticides and herbicides. a) 49,500,000 lbs. b) 500,000 lbs. c) 109,128,690,000 lbs. d) 1,102,310,000 lbs. e) none of these Answer: c Difficulty: Hard Learning Objective 1: LO 22.6.0 Discuss issues associated with the production and use of banned pesticides.

Section Reference: 22.6 The Manufacture and Use of Banned Pesticides Solution: 50 million metric tons of produce * (100 – 1 %) = 49.5 million metric tons per year not inspected 49,500,000 metric tons * 2204.62 lbs/metric ton = 109,128,690,000 lbs

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 23

Question Type: Multiple Choice

1. In 2004, the Steel Recycling Institute estimated that 43,913,800 tons of post-consumer scrap iron was incorporated into 107,470,000 tons of new liquid iron. What is the percentage of recycled content in the new iron? Answer to the nearest percentage point. a) 8% b) 41% c) 59% d) 64% e) 245% Answer: b Difficulty : Easy Learning Objective 1: LO 23.2.0 Identify methods to reduce the amount of waste produced.

Learning Objective 2: LO 23.2.1 Summarize how source reduction, reuse, and recycling help the volume of solid waste.

Section Reference 1: 23.2 Waste Prevention Solution: 100 * (43,913,800 tons / 107,470,000 tons) = 40.8614 % = 41%

2) In 2009, when the U.S. population was 306,000,000, the EPA estimated that it produced 243 million tons of municipal solid waste. On average, how many pounds of waste were produced per person each day? (1 ton = 2000 lbs) a) 0.45 lbs b) 4.35 lbs c) 79.67 lbs d) 1,623.05 lbs e) 646575.34 lbs Answer: b Difficulty: Medium Learning Objective 1: LO 23.1.0 Explain how soild waste is managed.

Learning Objective 2: LO 23.1.1 Distinguish between municipal solid waste and nonmunicipal solid waste.

Section Reference 1: 23.1 Solid Waste

Solution: {(243,000,000 tons of waste/year * 2000 lbs/ton) / 306,000,000 persons} / 365 days/year = 4.35 lbs/day/person.

3) It is estimated that each person in the United States produces an average of 2.1 kg (4.6 lbs) of solid waste per day. Assuming that the current U.S. population is 310.5 million, how much is produced per year (in lbs). Now calculate the total waste produced per year for India, with a current population of 1.21 billion, assuming the same levels of waste production per person. a) U.S.= 5.2 billion lbs/yr , India = 2.03 trillion lbs/yr b) U.S.= 52 billion lbs/yr, India = 20.3 billion lbs/yr c) U.S.= 521 billion lbs/yr, India = 20.3 trillion lbs/yr d) U.S.= 5.21 trillion lbs/yr, India = 2.3 billion lbs/yr e) none of these Answer: c Difficulty : Medium Learning Objective 1: LO 23.1.0 Explain how soild waste is managed.

Learning Objective 2: LO 23.1.1 Distinguish between municipal solid waste and nonmunicipal solid waste.

Section Reference 1: 23.1 Solid Waste Solution: for the U.S.: 310,500,000 * 4.6 * 365 = 521,329,500,000 or about 521 billion lbs/year India: 1.21 billion * 4.6 * 365 = 20,315,900,000,000 4) Sanitary landfills often charge “tipping fees” to accept solid waste. Tipping fees vary widely from one state to another. For example, in Nevada tipping fees are on the order of $11 per ton of solid waste and in Massachusetts they charge $69 per ton. How much less (in %) does Nevada charge per ton versus Massachusetts? a) 16% b) 11% c) 84% d) 58% e) none of these Answer: c Difficulty: Medium Learning Objective 1: LO 23.1.0 Explain how soild waste is managed.

Learning Objective 2: LO 23.1.2 Describe the features and problems of modern sanitary landfills.

Section Reference 1: 23.1 Solid Waste Solution: $69 - $11= $58, 58/69 * 100 = 84%

5) Incineration has been known to reduce solid waste by up to 90%. If the current U.S. population is approximately 310.5 million people and each person produces about 2.1 kg of solid waste per day, calculate how many kg of residual waste would remain at the end of one year if 100% of solid waste was incinerated. a) 232 trillion kg b) 209 trillion kg c) 23 million kg d) 209 million kg e) none of these Answer: e Difficulty: Medium Learning Objective 1: LO 23.1.0 Explain how soild waste is managed.

Learning Objective 2: LO 23.1.2 Describe the features and problems of a mass burn incinerator.

Section Reference 1: 23.1 Solid Waste Solution: (100 – 90 %) * (310.5 million people * 2.1 kg/day * 365 days/year) = 23,799,825,000 kg = 23 trillion kg

Package Title: Raven Quantitative Questions Course Title: Environment 8e WileyPLUS Chapter Number: Chapter 24

Question Type: Multiple Choice

1) In 1960 the world population numbered 3 billion with approximately 0.5 hectares of cropland per capita. If we assume the available cropland remains the same and the world’s population in 2011 is approximately 7 billion what is the approximate number of hectares of cropland per capita? a) 0.1 b) 0.2 c) 0.3 d) 0.4 e) 0.5 Answer: b Difficulty: Easy Learning Objective 1: LO 24.2.0 Discuss how sustainable living can be used to address global environmental problems.

Learning Objective 2: LO 24.2.3 Describe the extent of food insecurity and identify at least two ways to increase food production sustainability.

Section Reference: 24.2 Sustainable Living: A Plan of Action Solution: (3,000,000,000 x 0.5) / 7,000,000,000 = .21

2) The estimated per capita GNI PPP in highly developed countries is $32,370, while the estimated per capita GNI PPP of developing countries is approximately $5,150. On average, people in highly developed countries live on _____ per day, compared to the _____ per day that people in developing countries live on? a) 25, 5 b) 46, 8 c) 88, 14 d) 100, 22 e) 172, 34 Answer: c Difficulty: Medium Learning Objective 1: LO 24.1.0 Discuss how sustainable living can be used to address global environmental problems.

Learning Objective 2: LO 24.1.1 Define poverty, briefly describing this global problem.

Section Reference: 24.1 Sustainable Living: A Plan of Action Solution: (32,370/365) = $88.68 per day; (5,150/365) = $14.10 per day 3) In 1950, the world’s population was 2.5 billion. If the world population reaches 9.15 billion by 2050 the world population will have grown by ____% a) 166% b) 266% c) 366% d) 500% e) 1000% Answer: c

Difficulty: Medium Learning Objective 1: LO 24.1.0 Discuss how sustainable living can be used to address global environmental problems.

Learning Objective 2: LO 24.1.1 Define poverty, briefly describing this global problem.

Section Reference: 24.1 Sustainable Living: A Plan of Action Solution: [(9.15 x 100) / 2.5] = 366

4) If we assume that we share this planet with approximately 5.5. million other species and fivesixths have yet to be recognized and described; scientifically, that means approximately ______ remain to be classified? a) 1.2 million b) 2.2 million c) 3.8 million d) 4.6 million e) 5.2 million Answer: d Difficulty: Easy Learning Objective 1: LO 24.1.0 Discuss how sustainable living can be used to address global environmental problems.

Learning Objective 2: LO 24.1.2 Discuss problems relating to loss of forests and declining biological diversity, including the important ecosystem services that these resources provide.

Section Reference: 24.1 Sustainable Living: A Plan of Action Solution: [(5/6) x 5,500,000] = 4,565,000

5) The human population of 6.9 billion people uses an estimated 55% of accessible, renewable supplies of fresh water. If the rate of use remains constant per person, and the human population reaches 9.15 billion by 2050, what percentage of accessible, renewable supplies of fresh water will be used by humans? a) 62% b) 75% c) 80% d) 82% e) none of these choices is correct Answer: e Difficulty: Easy Learning Objective 1: LO 24.3.0 Identify the environmental problems caused by increasing consumption.

Learning Objective 2: LO 24.3.1 Explain how consumption overpopulation threatens environmental sustainability.

Section Reference: 24.3 Changing Personal Attitudes and Practices Solution: [(55x9.15)/6.9] = 72.93