1.  Energy Transfer Within Ecosystems APES~Mr. Plowman

2.  How do organisms grow?  What determines the productivity of an ecosystem?  Food chains, food webs, and trophic level pyramids

3. How Do Organisms Grow?

4. Photosynthesis builds biomass Biomass: the dry weight of an organism. No water weight

5. Energy flow and nutrient cycling

6. Primary Productivity  Gross Primary Production (GPP)  Rate at which an ecosystem’s producers convert solar energy into biomass.  Rate of photosynthesis  Net Primary Production (NPP)  NPP = GPP - R

7. Primary Productivity

8. Food Chains Primary Producer Primary Consumer Secondary Consumer Tertiary Consumer

9. Food Webs

10. Trophic Levels

11. Energy transfer is inefficient

12. Pyramid of Numbers Shows the number of organisms at each trophic level in a food chain.

13. Pyramids of Biomass

14. Final Thought  If humans have a limited amount of land and resources, what do you think is more sustainable:  Eating plants  Eating animals