1. How Ecosystems Work Part II Nutrient Cycling & Change in Ecosystems

2. Carbon Cycle The process by which carbon is cycled between the atmosphere, land water, and organisms. Plants convert atmospheric CO 2 into carbohydrates during photosynthesis and release CO 2 during cellular respiration. – Ex: Elodea http://mn-media-cluster-1.discoveryeducation.com/videos/1/Zeus_Animations/Carbon-Cycle_07-28_Fixed.swf

3. CARBON CYCLE

4. Nitrogen Cycle A process in which nitrogen is cycled between the atmosphere, bacteria, and other organisms. – Nitrogen-fixing bacteria are bacteria that live in plant roots and convert atmospheric nitrogen into ammonia. http://mn-media-cluster-1.discoveryeducation.com/videos/1/Zeus_Animations/Nitrogen-Cycle_07-28_Fixed.swf

5. Nitrogen Cycle

6. Phosphorus Cycle The movement of phosphorus from the environment to organisms and then back to the environment. (P) rock deposits land living organisms ocean Rarely occurs because phosphorus as a gas rarely occurs as a gas.

7. Phosphorus Cycle

8. Ecological Succession – A gradual process of change and replacement of the types of species in a community. Primary Succession – Occurs on a surface where no ecosystem existed before. Secondary Succession – Occurs on a surface where an ecosystem has previously existed. – Ex: Volcanoes – Pioneer Species - colonizes an uninhabited area and that starts an ecological cycle. Climax Community – The final, stable community in equilibrium with the environment.

9. What Type of Succession? 1 st Year2 nd Year3 rd Year

10. What Type of Succession?

11. Climax Community