Energy Flow in Ecosystem

1. Energy Flow in Ecosystem • Sunlight! • Producers, aka autotrophs use photosynthesis to create food. • Produce ATP and NADPH to then form gluclose

2. Both producers and consumers use cellular respiration to gain energy from food.

3. Consumers, aka heterotrophs rely on others for their food supply. • Herbivores – eat only plants • Carnivores – eat animals • Omnivores – eat both plants and animals

4. Scavengers – carnivores that eat already dead organisms. • Detritivores – break down dead tissue and waste products • Decomposers – complete break down of organic matter

5. Feeding Relationships • Energy flows one way. • Food Chain

6. Food Web

7. Trophic Levels

8. Ecosystem Productivity • Gross Primary Productivity (GPP): total solar energy captured by producers • Net Primary Productivity (NPP): GPP minus energy respired (R) • mg/L/day • kcal/day • kcal/m2/yr

10. Ecological Pyramids • Energy Pyramid – “Rule of 10” • Ecological efficiency: proportion of consumed energy that can be passed on.

11. Biomass pyramid – total mass of living tissue within a trophic level. • Amount of biomass present at a particular time is its standing crop. • Pyramid of Numbers