1. Ecosystems and Conservation Biology Chapter 36 Part 4

2. 36.4 Human activities can alter ecosystems

3. Impact on Chemical Cycles Humans literally move nutrients and resources from one place to another

4. Carbon Cycle Impacts Industrialization has increased atmospheric CO 2 levels –Burning of wood and fossil fuels

5. Carbon Cycle Impacts Deforestation –Clearing of forests for agriculture, lumber, etc. –Remove plants that convert CO 2 to O 2

6. Carbon Cycle Impacts CO 2 allows sunlight in, but traps heat –Greenhouse effect –Raises Earth’s average temperature Global warming

7. Nitrogen Cycle Impacts Humans move large amounts of nitrogen compounds into the water or air –Some sewage treatment –Fertilizer run-off

8. Nitrogen Cycle Impacts High nitrogen levels feed rapid growths of algae –Eutrophication –When algae die, the bacteria decomposing them use up all the O 2 in the water

9. Nitrogen Cycle Impacts Smokestacks and auto exhaust release nitrogen and sulfer compounds into air Combines with water –Nitric acid and sulfuric acid –Acid rain

10. Water Cycle Impacts Deforestation –Plants unable to return water to the atmosphere Using water faster than water cycle can replace

11. Biological Magnification As organisms take in nutrients, may also take in pollution –As organism’s nutrients pass through food web, accumulate in higher and higher amounts