1. Ecological Pyramids

2. Trophic levels
Trophic levels describe the various stages within ecological food chains or webs.

3. 5 course meal! Primary Producers Primary Consumers Secondary Consumers
Tertiary Consumers
Decomposers

4. How trophic levels work
Pyramids:
Trophic levels
Food Chains

6. Primary Producers photosynthetic or chemosynthetic organism that
Definition: A
photosynthetic or
chemosynthetic
organism that
synthesizes complex
organic molecules from
simple inorganic ones.
These are usually referred to as AUTOTROPHS

7. Primary Consumers An herbivore An Omnivore
Definition: An organism that feeds on producers
An herbivore
These gain their energy from eating plants.
An Omnivore
These gain their energy from eating plants or animals

9. Secondary consumers A carnivore
Definition: An organism that eats primary consumers
A carnivore
These get their energy by eating other animals

11. Tertiary Consumers
Definition: An organism that eats secondary consumers

13. Decomposers
Definition: Organisms, such as many bacteria and most fungi, that play beneficial roles in all ecosystems by breaking down and absorbing nutrients from dead and decaying organic matter

15. What about humans? Humans screw it up again!!!
Humans can fit in 3 of the 5 categories depending on diet.

16. Pyramids Three pyramids that we use in Ecology Pyramid of Numbers
Pyramid of Biomass
Pyramid of Energy

17. Pyramid of Numbers
This pyramid is constructed by taking the population statistics of each of the trophic levels.
Notice how the numbers drop significantly between levels.

18. Pyramid of Biomass
Biomass is calculated using the combined weight of all species of plants and animals that may exist within an ecosystem.

19. Pyramid of Energy
Energy is passed from one level to the next. Notice the approximate loss of energy between the levels.

21. Rule of 10’s
When progressing up the pyramid of energy there is a 90% drop in the amount of energy between levels.
Example: If we start with the primary producer containing 1000 units of energy how much energy will be present for the tertiary consumer?

22. Primary Producers= 1000 units of energy
Primary Consumers= 100 units of energy
Secondary Consumers= 10 units of energy
Tertiary consumers= 1 unit of energy
It takes the energy of 1000 plants to feed a tertiary consumer 1 unit of energy!

23. Conclusion