• A healthy diet generally requires 2,500 calories per day for the average male & 2,000 per day for the average female
• Proper nutri8on also requires a balanced intake of protein, carbohydrates, & fat
• Wheat & rice supply over half the human caloric intake • However, most grain grown in the US is grown for animal feed
• It takes about 16lbs. of grain to produce 1lb. of edible meat
• Malnutri;on & undernourishment occur most frequently in children & the elderly who live in less developed countries
• • • • •
Marasmus Kwashiorkor Vitamin A Anemia Goiter
GREEN REVOLUT ION
• Green Revolu;on: Increases crop yields • 1ST green revolu8on occurred 1950-‐1970 • Rice, wheat, & corn • Large amounts of fer8lizers, pes8cides, H2O • World grain tripled in produc8on
1963
• 2nd Green Revolu;on is occurring today • It involves GMOs that produce the most yields per acre
• Food produc8on in the future may be limited by its serious environmental impacts, including: • soil erosion & degrada8on • deser8fica8on • water & air pollu8on • greenhouse gas emission • destruc8on of biodiversity
• Loss & degrada;on land including grasslands, forests, & wetlands in cul8vated areas
• Fish kills from pes;cide runoff • Killing wild predators to protect livestock
• Loss of gene8c diversity of wild crop strains replaced by monoculture strains
• Erosion • Waterlogging • Loss of fer8lity • Deser8fica8on • Saliniza8on • Increased acidity
• Topsoil erosion is a serious problem in parts of the world – can cause loss of fer;lity
Soil profile review Soil layers are called horizons & are assigned leUers
O. Organic material E. Leached zone A. Topsoil
B. Subsoil C. Weathered bedrock R. Bedrock
• Human ac8vi8es like agriculture accelerates deser8fica8on
• Methods that reduce soil erosion & promote soil conserva;on are: • Terracing • Contour plan8ng • Alley cropping/agroforestry • No-‐8ll/low-‐8ll
(a) Terracing
(c) Alley cropping
(b) Contour planting and strip cropping
(d) Windbreaks
Stepped Art Fig. 12-‐24, p. 302
• • • • •
Water waste (massive irriga8on) Aquifer deple8on Increased runoff & flooding Pollu8on from pes8cides & fer8lizers Algal blooms & fish kills caused by runoff of fer8lizers & agricultural wastes
• Saliniza;on: Gradual accumula8on of salts in the soil from irriga8on water • Lowers crop yields & can even kill plants • Affects 10% of world croplands
• Waterlogging: Irriga8on water gradually raises water table • Can prevent roots from ge_ng oxygen • Affects 10% of world croplands
• Emission of greenhouse gas CO2 from fossil fuel use
• Emissions of greenhouse gas N2O from use of inorganic fer8lizers
• Emission of greenhouse gas methane (CH4) by caZle (mostly belching)
• Nitrates in drinking water (blue baby) • Pes8cide residues in drinking water & food • Contamina8on of drinking & swimming water from livestock wastes • Bacterial contamina8on of meat (E.Coli)
• Gene;cally Modified Organisms (Crops) could solve some problems but then create other ones • Advantages: • Needs less fer8lizer, need less water, more resistance to disease/insects, grows faster...
• Disadvantages: • Unpredictable gene8c & ecological effects; no increase in yields; superweeds; lower diversity
• Advantages: • Can save human lives, increase food supplies, increase profits, work quickly,
• Disadvantages: • Accelerate rate of gene8c resistance in pests, expensive, may harm wildlife/people, may cause pollu8on
• David Pimentel: Pes8cide use has not reduced US crop loss to pests
• Despite the widespread applica8on of pes8cides in the US, pests (including insects & weeds) destroy 37% of all poten8al crops
• Crop losses con8nue to rise in part due to changes in agricultural prac8ces
• Pes;cide industry refutes these findings
• Can can we protect crops from pests in a more sustainable way?
• Integrated Pest Management (IPM) • Coordinate cul;va;on, biological controls, & chemical tools to reduce crop damage to an economically tolerable level • Reduces pollu+on & pes+cide costs • Disadvantages: • Requires expert knowledge • High ini8al costs • Government opposi8on
• IPM stands for _Integrated ______________________ Pest Management Modified Organism • GMO stands for _Genetically _______________________ • The smallest par8cle of soil is _CLAY _____
• Gradual accumula8on of salts in the soil from irriga8on water is called ________________ Salinization • The cul8va8on of a single crop is called monoculture & may lead to biodiversity loss ___________
Wheat, rice, corn • Three main crops are:______________________
• A nutri8onal imbalance caused by the lack of important dietary elements/the inability to RIT ION absorb essen8al nutrients is _MALNUT _____________
• One of the most effec8ve ways to irrigate system farmland is through a _Drip ____________ • Most of water used through mass irriga8on systems is lost to _evaporation __________ • Ladybugs & wasps serve as ______________ biological pes8cides
• We’ve discussed the environmental impact that high-‐input, highly industrialized agriculture can have • We discussed water pollu8on, air pollu8on, soil degrada8on, human health, ecological impact, etc. • We have also discussed soil conserva8on techniques & sustainable prac8ces
• Sustainable agriculture: doesn’t deplete soil, pollute water, or decrease gene8c diversity
• Low-‐input agriculture: uses smaller amounts of pes8cide, fer8lizers, growth hormones, water, & fossil fuels -‐-‐-‐ depends more on man/drae animal labor
• Organic agriculture: uses NO synthe8c fer8lizers, insec8cides, herbicides, etc. Relies on biological approaches
• Sustainable agriculture mimics natural ecosystems • For example, small-‐scale Japanese farmers add ducks to rice fields • Ducks eat weeds, insects, snails • Their waste is fer8lizer • Their paddling oxygenates the water • Fish & ferns provide food & habitat
TEd Video A powerful thinker and globe-‐tro_ng advisor on sustainability, Louise Fresco says it's 8me to think of food as a topic of social and economic importance on par with oil -‐-‐ that responsible agriculture and food consump8on are crucial to world stability.
"There is no technical reason why we could not feed a world of nine billion people. Hunger is a matter of buying power, not of shortages."
Louise Fresco on feeding the whole world (18:04)
• Now we will focus more on livestock, poultry, & Aquaculture
• As wealth has increased, so has the consump8on of animal products • Ea8ng animal products leaves a greater ecological footprint than ea8ng plants • Feedlots create waste & other environmental impacts, but they also relieve pressure on lands that could otherwise be overgrazed
• Since 1950, global meat produc8on has increased fivefold & per capita meat consump;on has doubled
• Ea8ng meat is far less energy efficient than ea8ng crops • 90% of energy is lost from one trophic level to the next
• Land & water use needed to raise food for livestock • Producing eggs & chicken meat requires the least space & water • Producing beef requires the most
• When we choose what to eat, we choose how we use resources
• Feedlots (factory farms) aka CAFOS (Concentrated Animal Feeding Opera8ons) • Huge warehouses or pens deliver food to animals living @ extremely high densi8es • Over half the world’s pork & most of its poultry are grown in CAFOs
High consumption leads to feedlot ag. • Tradi;onal ag. keeps livestock on grasslands • Feedlot animals are fed grain grown on cropland • One-‐third of the world’s cropland is fed to livestock
Advantages:
• Feedlot ag. allows economic efficiency • Greater produc8on of food • Unavoidable in countries like the US
• Feedlot ag. also reduces grazing impacts on land & manure can be applied to fields as fer8lizer
disadvantages:
High consumption leads to feedlot ag. • Feedlots produce huge amounts of manure & urine that can cause eutrophica;on & waterborne pathogens • Crowded, dirty housing causes outbreaks in disease • Heavy use of an8bio8cs/hormones • Chemicals are transferred to people • Microbes evolve resistance to an8obio8cs • Air pollu;on: odors; GHGs (Methane)
• CAFO stands for... Concentrated Animal Feeding Operation • One of the most effec8ve ways to irrigate system farmland is through a _Drip ____________ • As food moves up trophic levels, the amount of energy available _________________ decreases • Most grain is grown in the US to feed COWS _____; this animals contribute to ______ CH4 in the atmosphere
• Human popula8on is forever increasing... however, farmers are able to grow enough food to feed this popula8on @ this present 8me • Most people suffer from food insecurity due to lack of _MONEY _____ & _ACCESS _______
• Globally, the consump8on of animal products like meat, eggs, & milk is on the rise • This growing demand has led to an increase in the amount of cropland needed to feed these animals • Remember, most grain grown in the US is to feed caZle • Most caUle live on rangeland or pasture
• Rangeland: provides food for grazing & browsing animals without plowing & plants • Pasture: is plowed, planted, and harvested to provide forage for animals
• Rangelands in the US are oeen overgrazed due to poli;cal & economic pressures • The Natural Resources Defense Council reports that 30% of public rangelands are in fair condi;on • 55% are in poor to very poor condi8on • Although rangeland is protected, there are limited funds to enforce conserva8on policies
• Due to overgrazing & concern for land degrada;on, CAFOs and feedlots are considered a beUer alterna8ve • Animals in a CAFO are not grazing in a pasture, but are being fed with concentrated feed
• E.coli – intes8nal bacteria cause illness or death • Vegetables are contaminated by irriga+on water & flooding; can be found in undercooked ground beef • Salmonella – intes8nal bacteria cause food poisoning • Found in contaminated eggs, poultry, meat, unpasteurized milk/juice, cheese, contaminated raw fruits & vegetables, spices, & nuts • Campylobacter -‐ found most oeen in food, par8cularly in chicken • Food is contaminated when it comes into contact with animal feces
Campylobacter
Salmonella
E.Coli
• Fer;lizer nitrogen & phosphorus • Causes excessive growth of algae – ____________ Eutrophication • Well-‐known problems include: • Excess manure • Nutrients • Salts • Odor
• IPM stands for _Integrated ______________________ Pest Management • IPM involves biological/more natural methods of pest management • Replaces chemical op8ons
1. Growing marine or aqua8c species in net pens or tanks is known as A. Cross cul8va8on B. A risk-‐free industry C. Bioculture D. An easy source of iodine E. Aquaculture
2. When DNA is combined in ways to augment certain characteris8cs in a species’ natural growth, the result is known as a A. Nonna8ve species B. Relict species C. Transplanted organism D. Gene8cally modified organism E. Nonviable organism
3. When nontarget fish species or other marine animals are caught in nets or through other fishing methods, they are called A. Surplus species B. Bycatch C. Alternate species D. Trash fish E. Game fish
4. It has been es8mated that over 60% of all processed food in America contains A. GMO ingredients B. FaUy acids C. Carcinogens D. DDT E. phosphorus
5. Hormones that stop larval growth, combined with mechanical vacuuming of bugs from plants, are examples of A. Crop rota8on B. Low input agriculture C. Integrated pest management D. Cross discipline ac8va8on E. Plant deser8fica8on
6. One method to conserve water & make sure it gets directly to plant roots is through A. Sieve sleeve irriga8on B. Drip irriga8on C. Rolling sprinklers D. Flood irriga8on E. Crop circle sprinklers
7. Organic farms have lower feed and veterinarian costs since their animals are A. Smaller in size B. Crowded into barns C. Healthier D. Raised in larger herds E. Fed GMO ingredients
8. Which of the following has cause the greatest increase in the introduc8on of marine alien species into new ecosystems? A. Tourism B. Air travel C. Shipping D. Commercial fishing E. Home aquariums
9. Freshwater used in developing countries is primarily used for A. Agriculture B. Industrial purposes C. Drinking water D. Domes8c needs E. All of the above are used in equal propor8ons
10. Which of the following was NOT a major component of the First Green Revolu8on? A. B. C. D.
Gene8c engineering of food crops Widespread use of synthe8c fer8lizers Widespread use of pes8cides Development of major modern irriga8on projects E. Development of new crop varie8es through selec8ve breeding technology