1. Chapter 10 Ecosystems p

2. What is an ecosystem?
A community of living organisms interacting with one another and with non-living parts of the environment they live in
Levels:
Individual population community ecosystem

3. Trophic relationships
Feeding connections among living organisms in an ecosystem
Can be represented by a food chain
3 trophic levels:
Producers
Consumers
Decomposers

4. Producers Plants Autotrophic (self feeding)
Convert carbon dioxide to glucose with help of solar energy
Beginning of food chain, most abundant, they introduce energy to an ecosystem

5. Consumers Insects or animals
Heterotrophic (feed on other living organisms)
4 types:
Primary or 1st order (herbivores), feed on producers (plants)
2nd, 3rd, 4th order consumers, eat consumers of preceding order (usually carnivores, can also be omnivores)

6. Decomposers Worms, fungi, bacteria, some insects
Organisms that feed on waste and remains of other living organisms (dead leaves, wood, animal remains, excrement, etc.)
Convert organic matter (rotting organisms) into inorganic matter (nutrients)

7. Food chains
A representation of the trophic relationships between organisms
Linear, a chain in which each member eats the preceding one.

8. Food webs
A representation of all feeding relationships that exist in an ecosystem (also called a trophic network)

9. Chemical recycling
When decomposers make inorganic (non-living) matter available in an ecosystem by breaking down organic (living) matter.
Making nutrients available by decomposing waste

10. Biomass
The total mass of organic matter in an ecosystem at any given time.

11. Material and energy flow
Exchange of matter and energy between organisms and environment
From one trophic level to another energy is lost (waste, movement, growth, reproduction, heat)
Only 10% of energy is
available at next level
Energy IS NOT recycled,
we need a constant supply
from the sun (p.325)

12. Primary productivity in ecosystems
The amount of new biomass generated by producers (energy available from plants)
limits the # of organisms that can live in an ecosystem
Influenced by:
Sunlight
Water
Nutrients
Temperature