1. Energy Flow in Ecosystems
Everything organisms do in an ecosystem requires ENERGY!!!

2. The Ultimate Source of Energy for ALL Ecosystems

3. Primary Productivity
Rate at which organic material is produced by photosynthetic organisms

4. Producers
Make energy-storing molecules

5. Consumers
Consume other organisms to get energy to build molecules

6. Energy moves through TROPHIC levels
Food Chain
Food Web
Describes path of energy flow

7. Trophic Levels:
Producers are the first (bottom) level

8. Trophic Levels:
Consumers make up the additional levels
(1, 2, 3)

9. Consumers Herbivores Carnivores Omnivores Eat plants and meat
Eat meat
Omnivores
Eat plants and meat
Detritivores (decomposers)
Eat organic waste and dead material
Necessary for the recycling of nutrients

10. Primary Consumers
Eat producers
Herbivores
Second trophic level

11. Secondary Consumers Eat primary consumers (herbivores) Carnivores
Omnivores

12. Tertiary Consumers
Eat other carnivores
Top of food chain

14. Energy is always lost when energy is transferred – heat
Amount of energy decreases as it passes through ecosystem
Only 10% is transferred
Energy Pyramid
Represents flow of energy

15. Energy Pyramid

17. Energy Pyramid Trophic levels are limited due to available energy
Too much is lost to support top
Amount of energy available = biomass
Not number of organisms – too inaccurate

18. Biomass Dry weight of tissue and other organic material
Each higher level contains only 10% of biomass found in level below it

20. Food Web
Food Chain