organic waste and dead organisms intricate pathways of energy flow and material cycling contains the autotrophs which build energy containing molecules  (primarily plants) provide an Energy-fixation and Nutrient-concentration 2 types: Photoautotrophs - plants and some Protista Chemoautotrophs - bacteria contains the primary consumers which eat the primary producers, including herbivores, decomposers and detritivores, e

1. Detritus

organic waste and dead organisms

2. Food Webs

intricate pathways of energy flow and material cycling

3. First Trophic Level

contains the autotrophs which build energy containing molecules

4. Autotrophs

(primarily plants) provide an Energy-fixation and Nutrient-concentration
2 types: Photoautotrophs - plants and some Protista
Chemoautotrophs - bacteria

5. Second Trophic Level

contains the primary consumers which eat the primary producers, including herbivores, decomposers and detritivores, e.g. insects, deer, wildebeest

6. Third Trophic Level

contains the secondary cosumers, primary carnivores which eat the herbivores, e.g. mice, spiders and many birds

7. Fourth Trophic Level

contains the tertiary consumers, secondary carnivores who eat the primary carnivores, e.g. weasel, owl, sharks, and wolves

8. Gross Primary Productivity

the rate at which the primary producers capture and store energy per unit time

9. Net Primary Productivity

lower since primary producers expend energy during respiration

10. Ecological Pyramid

representation of trophic structure with primary producers at the base