1. Ecology --The Interrelationships between Organisms and their Environment

2. Interacting Factors – biotic and abiotic factors

3. Habitats –places with particular set of physical factors …..

4. Aquatic habitats -freshwater
Running waters

5. Aquatic habitats - freshwater
Slow moving waters

6. Aquatic habitats – marine_rocky

7. Aquatic habitats – marine_sandy

8. Aquatic habitats – marine_muddy

9. Terrestrial habitats – grassland

10. Terrestrial habitats – woodland_tpk

11. Woodland wildlife-tpk

12. Agricultural habitats

13. Microhabitats

14. Biome

15. Biosphere

16. Physical environment-light

17. Physical environment-photoperiod

18. Physical environment-light _affecting development of plants

19. Physical environment-nocturnal animals

20. Physical environment-wind

21. Physical environment_temperature _cold blooded vs warm blooded

22. Physical environment_temperature_warm blooded

23. Physical environment_temperature

24. Physical environment_temperature

25. Physical environment_oxygen _fast flowing stream

26. Physical environment_slow moving water_oxygen

27. Physical environment _oxygen_eutrophication_red tide

29. Physical environment_soil layers I
The uppermost is called the organic horizon. It consists of detritus, leaf litter and other organic material lying on the surface of the soil. This layer is dark because of the decomposition that is occurring. This layer is not present in cultivated fields.
Below is the A horizon or topsoil. Usually it is darker than lower layers, loose and crumbly with varying amounts of organic matter. In cultivated fields the plowed layer is topsoil. This is generally the most productive layer of the soil. This is the layer that soil conservation efforts are focused.

30. Physical environment_soil layers II
The next layer is the B horizon or subsoil. Subsoils are usually lighter in color, dense and low in organic matter. Most of the materials leached from the A horizon stops in this zone.
Still deeper is the C horizon. It is a transition area between soil and parent material.
At some point the C horizon will give up to the final horizon, bedrock.

31. Physical environment_soil ecosystem

32. Soil ecosystem