Carbon & Nitrogen Cycles SE: 12E

1. Carbon & Nitrogen Cycles SE: 12E Describe the flow of matter through the carbon and nitrogen cycles and explain the consequences of disrupting these cycles.

2. Carbon Cycle • Carbon makes up less than 1% of the Earth’s crust and atmosphere. • All living things depend on carbon compounds.

4. How does matter flow through the Carbon Cycle? • Carbon mainly found in atmosphere as CO2. CO2 leaves the atmosphere when its dissolved in water or taken up by plants for photosynthesis. • Carbon is released into the atmosphere during cellular respiration, geologic processes such as volcanic eruptions, & when fossil fuels or forests are burned.

6. What happens when the carbon cycle is disrupted? • Human activity such as burning fossil fuels and forests release CO2 into the atmosphere faster than it can be removed by natural processes.

7. 3. CO2 is a greenhouse gas that helps keep heat from leaving atmosphere. The increased levels of CO2 contributes to rising temperatures and the global climate change.

11. 4. When CO2 dissolves in water, carbonic acid forms. As more acid forms, oceans are becoming more acidic. 5. Certain organisms have a low tolerance for changing pH levels in the ocean. This can lead to loss of biodiversity.

14. 6. What happens if there is too much CO2 in the atmosphere? • Global warming 7. What would cause too much CO2 in the atmosphere? • rainforest deforestation • grassland conversion • too much pollution – from cars, factories

15. What are the causes of the disruption to carbon cycle? Deforestation - removal of a forest or stand of trees where the land is thereafter converted to a nonforest use Grassland Conversion – altering grasslands to farmland

19. Why does deforestation/grassland conversion occur? • People need land to grow crops or raise animals • People need land to live – development of houses, cities, shopping malls, etc…

20. Nitrogen Cycle • Nitrogen gas makes up 78% of the Earth’s atmosphere. 8. Nitrogen is removed from the atmosphere by a process called nitrogen fixation. The nitrogen is “fixed” or changed into a form that living things can use.

22. Nitrogen Fixation • Certain bacteria in the soil and water are able to fix nitrogen. Some of these bacteria live inside the roots of certain plants. The plants are then able to use the nitrogen. 9. Lightning can also fix nitrogen. 10. On the other hand,Denitrifying bacteriareturn nitrogen to the atmosphere thus removing nitrogen from soil.

25. What happens when the Nitrogen Cycle is disrupted? 9. Farmers often add fertilizer to the soil to increase plant growth. Fertilizer runoff can affect the balance of nitrogen in water (rivers, lakes, streams). 10. Eutrophication is the process in which nitrogen dissolves in a body of water and stimulates growth of plants and algae.

27. When plants and algae die, bacterial populations that feed on dead matter rise. • These bacteria consume so much oxygen from the water that fish and other aquatic animals cannot survive.

29. 11. Acid precipitation aka acid rain is another consequence of disrupting the nitrogen cycle. • The pH levels of soil and water are altered and leads to death of plants and animals. • Acid rain can also cause harmful metals to leach from pipes and enter drinking water.

34. Plants need Nitrogen, what would happen if there wasn’t enough nitrogen for plants? Plants wouldn’t have nutrients to grow & would be very small