Key Takeaways

KEY TAKEAWAYS

• There are different cycles of nutrients with the nitrogen cycle being an important one as nitrogen is a limiting nutrient in the formation of living things.

• There are nitrogen fixing bacteria that take nitrogen from the atmosphere and denitrification bacteria that put the nitrogen back into the atmosphere.

• Ecosystems can be large or small but involve the interaction of organisms in a specific area with the physical characteristics of the environment.

• Population ecology is the study of different organisms and their growth or lack of growth in numbers in a specific area.

• The biosphere is the totality of the ecosystems and encompasses areas deep within the earth and parts of the atmosphere but not in deep space.

• Climate change has happened for billions of years, even when humans did not inhabit it the earth

• Humans have affected the climate in irreversible ways through an increase in greenhouse gases, deforestation, and other human activities.