Ecology is The study of the distribution and abundance of organisms, AND

2. Ecology is The study of the distribution and abundance of organisms, AND the flows of energy and materials through organisms and the physical environment.

3. Outline • Climate • Energy flow • Biogeochemical cycles

4. Picture of sun

5. Solar energy drives global climates

6. Global atmospheric circulation

8. Global atmospheric circulation

10. Global oceanic circulation

11. The amount of heat that an ecosystem receives is determined by: • The angle of the sun (latitude)

12. The amount of heat that an ecosystem receives is determined by: • The angle of the sun (latitude) • Altitude

13. The amount of heat that an ecosystem receives is determined by: • The angle of the sun (latitude) • Altitude • Wind

14. Local climate

15. Local climate Maui cloud

16. Local climate • Land-shore system

17. The amount of heat that an ecosystem receives is determined by: • The angle of the sun (latitude) • Altitude • Wind • Ocean currents

19. Energy flow through ecosystems Only 5% of the solar energy that arrives on earth is captured by photosynthesis.

20. Energy flow through ecosystems Only 5% of the solar energy that arrives on earth is captured by photosynthesis. The energy captured powers life.

21. The 2nd law of thermodynamics

22. The 2nd law of thermodynamics • When energy is converted from one form to another, some of it becomes unavailable to do work...

23. The 2nd law of thermodynamics • When energy is converted from one form to another, some of it becomes unavailable to do work... • Key to understanding energy flow through ecosystems.

24. Gross primary productivity(GPP) • The amount of energy that plants assimilate through photosynthesis.

25. Gross primary productivity(GPP) • The amount of energy that plants assimilate through photosynthesis. • CO2 + H2O + light = energy compounds.

26. Gross primary productivity(GPP) • The amount of energy that plants assimilate through photosynthesis. • CO2 + H2O + light = energy compounds. • Fixed carbon = energy

27. Net primary productivity(NPP) • GPP – plant respiration = NPP • NPP is: • Food • Fiber • Fuel • Shelter

28. Climate drives NPP

29. NPP provides energy to heterotrophic organisms

30. Trophic levels Number of steps through which energy passes before an organisms uses it.

31. Trophic levels

32. Trophic levels

33. Trophic levels

34. Trophic levels

35. Trophic levels

36. Energy is lost between trophic levels • Energy decreases as it moves from lower to higher trophic levels • The “trophic pyramid”

40. The efficiency of energy transfer is determined by:

41. The efficiency of energy transfer is determined by: • How much of the energy at one trophic level gets eaten by another trophic level

42. The efficiency of energy transfer is determined by: • How much of the energy at one trophic level gets eaten by another trophic level • How those organisms divide the ingested energy between production and respiration.

43. A food web

44. Food webs in real ecosystems are complex

45. Some ecosystems are not powered by direct sunlight

46. Deep sea vent ecosystems

47. Humans manipulate energy flow • Forestry • Agriculture • Fisheries management • Game management • Land use change • Burning fossil fuels...

48. Assume that energy transfer efficiency between trophic levels is 10%. • How much grain would be required to produce 70 Kg of human biomass if that grain is first eaten by cows, and the cows are then eaten by humans? • How much grain would be required to produce 70 Kg of human biomass if the humans ate the grain?