1. Ecosystem Structure

2. Food Chain  1 st level of all food chains must be the producers Producers have the ability to trap energy and produce carbohydrates (sugars)  Called Autotrophs  Ex. Algae, plants, trees, grasses

3. Food Chain  The next levels are the Consumers Those that eat to obtain energy – heterotrophs  Primary – herbivores  Secondary – small carnivores or omnivores  Tertiary – large carnivores

4. Food Chain  It starts and ends with a very important group called the decomposers Recycle the nutrients and make it available for the chain to use again.

5. Food Chain – Food Web  Each level is called a Trophic Level  If there are multiple options at each level it is called a food web.

6. Trophic Levels  All nutrients and energy has the potential to be passed on to the next level.  Because each level eats several of the level below there is a building effect called biological magnification. This build up could be a pollutant like DDT in Bald Eagles. – causing an issue at the upper levels.

7. Biological Magnification

8. Ecological Pyramids  The total mass of all the organisms in an ecological community is called the biomass. Each trophic level contains stored energy representing the potential food available to organisms at the next level. Only about 10% of the biomass from one level can transfer to the next The number of organisms (biomass), and the amount of energy is 1/10 th of the level before. All biomass starts with producers when they trap CO2 from the atmosphere into carbohydrates.

9. Ecological Pyramids

10. Ecosystem  The ecosystem is made up of several trophic levels that rely on each other to continue to survive and develop.  The producers are the foundation. The biomass available to the upper trophic levels depends on the producer numbers.