1. Ecology Review

2. Ecology is…
the study of the interactions/relationships between living organisms and their biotic and abiotic environments.

3. * surroundings of an organism that affect its life and development.
ENVIRONMENT
* surroundings of an organism that affect its life and development.

4. An environment is characterized by the ABIOTIC and BIOTIC factors.
Abiotic factors are non-living.
chemistry, physics and geology.
weather, seasonal changes, tides, air quality, and water quality
Biotic factors are living
Species Population Community ECOSYSTEM: all of the communities that live in an area together with the abiotic factors in the environment

5. Biosphere All the parts of Earth that support life.
20km thick (12.4 miles)
Most life on Earth exists between 500m below the surface of the ocean and about 6km above sea level.

6. Abiotic and Biotic factors work together:
Geographic location (latitude and longitude) determines abiotic factors(temp and climate) which supports specific ecosystem.

7. Habitat: the actual place an organism lives
An organism’s niche
Habitat: the actual place an organism lives
Niche: both living and non-living parts of an ecosystem that determines an organism’s role in the ecosystem.

8. Organisms Interactions
-Producers -Consumers -Decomposers -Scavengers

9. Producers Autotrophic -make their own food.
Phototrophic organisms use photosynthesis and contain chlorophyll
Chemotrophic organisms use chemicals other than H20, such as H2S

10. PRODUCERS!!!

11. Consumers
Heterotrophic –ingest their own food. -Herbivores feed on vegetation (producers).
-Carnivores feed on herbivores or on other carnivores.
-Omnivores feed on both producers and consumers
-Scavengers feed on dead or decaying organisms

12. CONSUMERS!!!

13. Scavengers

14. DECOMPOSERS
- Heterotrophs
Recycle dead organic matter into inorganic nutrients
Use by soil.
-Bacteria and Fungi and worms

15. Energy in the Ecosystem
Producers produce energy through photosynthesis (Sun)
Energy = Glucose
Consumers take in this energy when they eat producers or other consumers.
Plants absorb less than 1% of the sunlight that reaches them!

16. Trophic levels Different feeding levels of organisms in an ecosystem.
Producers are the first trophic level
These relationships can be seen in an ecological pyramid.
Biomass: the total amount of organic matter

17. The Ten Percent Law Most energy does not become biomass.
Only about 10% of the energy entering one trophic level forms biomass for the next trophic level.
Known as the 10% law.

18. Ecological Pyramid: Energy
Shows the relative transfer of energy (joules) from one trophic level to the next.

19. Food Chains
-Series of organisms that transfer food between the trophic levels
-One species at each level
-Simple chain.
-The arrow points toward the organism doing the ‘eating’.

20. -Shows the network of food chains
Food Webs
-Shows the network of food chains
-Most organisms feed on more than one type of organism at different trophic levels.

21. How do Food Webs show complexity?
Food Webs represent the diversity and stability of an ecosystem
Complex Food Webs = more stable ecosystem

22. Relationships in the ecosystem
Predator/Prey: One organism (predator) consumes another (prey).
Competition: two or more organisms compete to use the same limited resources

23. Coevolution
When two or more species evolve in response to each other, it is called coevolution.
Plants and insects = Pollination
Bees want the nectar from flowers and the bees transport the pollen for the flower

24. Limiting Factors -Factors which are in low supply
-Limit the growth of a population
-Ex – availability of food, water, shelter, and space; competition for resources, predation, and disease

25. Carrying Capacity
-Maximum number of individuals of a population that can be supported in a given environment sustainably.

26. Density Independent
-Factors that affect populations regardless of their size
-Examples:
Unusual weather (Draught, Hurricanes)
Season cycles
Human activities (damming rivers, forest cutting)

27. Density Dependent -Limiting factors that depend on population size
-Limiting only when population density reaches a certain level
-Does not affect small, scattered populations
-Ex-Predation, competition, disease and parasitism