1. Ecological Pyramids Chapter 2 Section 2b

2. Learning Targets
1. I can model the use of ecological pyramids

3. Ecological Pyramids
Another model that shows how energy flows through ecosystems is the Ecological Pyramid
Ecological Pyramids are models used to represent trophic levels in ecosystems
There are 3 different ecological pyramids:
Pyramid of Energy
Pyramid of Biomass
Pyramid of Numbers

4. Pyramid of Energy
In an ecosystem, only 10% of the energy from each organism in a food chain is actually passed on when consumed for food
90% of the energy is lost through cell processes and as heat
Pyramids of Energy model this effect on an ecosystem

5. Pyramid of Energy
In a Pyramid of Energy, each level represents the amount of energy that is available to that trophic level.
With each step up the pyramid, energy decreases

6. Pyramid of Biomass
Ecologist also study how biomass is effect at each trophic level using a Pyramid of Biomass
Biomass – the total mass of living matter at each trophic level
As you move up the pyramid, there is less biomass because there is less energy available at that trophic level

7. Pyramid of Biomass Tertiary Consumer Secondary Consumer
Primary Consumer
Producer

8. Pyramid of Numbers
The last type of pyramid is the Pyramid of Numbers, which represents the number of organisms present at each trophic level
The relative number of organisms at each trophic level decreases because there is less energy available to support the organisms

9. Ecological Pyramids