1. Ecosystems

2. What is an ecosystem?
Ecology-the study of interactions of living organisms with one another and with their physical environment
Ecosystems are complex and defined by many smaller parts combined to form the whole

3. Habitat-the place where a particular population of a species lives
Community-the many different species that live together in a a habitat
Ecosystem-consists of a community and all the physical aspects of a habitat

4. Abiotic vs. Biotic Abiotic Factors-nonliving factors of an ecosystem
Biotic Factors-living factors of an ecosystem
Biodiversity-the total number of species living within an ecosystem

5. Ecosystems Change Over Time
Ecological Succession is the change of ecosystems over time
Primary Succession-succession where plants have never grown
Secondary Succession-succession where plants have previously inhabited an area

6. Primary Succession

9. Climax community??
May take 100’s or 1000’s of years to reach this stage
Stage at which system has reached steady-state equilibrium
Most permanent of all the stages
Difficult to identify

10. Disturbance They damage biological communities
Include events such as storms, fires, floods, droughts, overgrazing, and human activities
They damage biological communities
They remove organisms from communities
They alter the availability of resources

13. Intermediate Disturbance Hypothesis
If widespread disturbances occur frequently, diversity will be limited
If diversity is high, only moderate disturbances have been occurring with moderate frequency

14. Energy Flow in Ecosystems
Most life of Earth depends on photosynthetic organisms
Primary Productivity-the rate at which organic material is produced by photosynthetic organisms
Producers- organisms that capture solar energy
Consumers- organisms that consume food

15. Trophic Levels
Trophic Level- a graphic organizer based on an organism’s source of energy
Primary Producer, Primary Consumer, Secondary Consumer, Tertiary Consumer, Quaternary Consumer

16. Food Chain vs. Food Web
A food chain shows an incomplete path of NRG
A food web shows a more realistic path of NRG

17. What Do You Eat? Herbivore- plants Carnivore- other organisms
Omnivore- plants and animals
Detritivore- organic wastes and dead bodies
Decomposer- cause decay

19. Productivity Rule
Ecosystems are generally more productive near the equator
More NRG available for living organisms
NRG Pyramid-diagram in which each trophic level is represented

20. Rule is only about 10% of NRG actually gets transferred to the next trophic level