1. Final Exam Thursday 7-10 pm here Non-cumulative Same format Covers all lectures since Exam 2 200 of 1000 points Sample ?s/Answers on web under Exam 3 Use lecture outlines, book + PP to study. QUESTIONS?

2. levels of ecological systems:

4. Ch 26: Global Ecology

6. A. Human activities threaten local ecological processes. 1.Overexploitation 2.Introduce exotic species 3.Habitat conversion 4.Irrigation 5.Fertilizer --> eutrophication

7. 1. overexploitation of marine animals…

8. 1. overexploitation by grazers that leaves the land unproductive…

9. Shifting cultivation = sustainable if on a long rotation cycle (with low population density).

10. 2. Introduction of exotic species… Purple loosestrifeZebra mussels

11. Spread of zebra mussels in waterways

12. Plenty of Invasive Species on Continents Great Lakes - zebra mussels, gobies, sea lamprey Starlings, house sparrows mosquito fish, gypsy moth Kudzu, water hyacinth garlic mustard, purple loosestrife, salt cedar, tumbleweed

13. Nile perch vs. cichlid fish in Lake Victoria

14. 3. Via habitat conversion…

15. And via bad land use practices… 1% of topsoil is eroded each year.

16. 4. via irrigation…

17. 5. via overfertilization ---> eutrophication + anoxia…

18. B. Toxins accumulated in the environment… 1. Acids (e.g. Sulfuric acid drainage from coal mines)…

19. and acid rain from coal-burning industries.

20. 2. heavy metals…

21. 3. organic compounds 4. radiation

22. C. Atmospheric pollution threatens on a global scale… 1.Ozone (O 3 ) + UV radiation a. at surface

23. b. Ozone in upper atmosphere CFCs and ‘black hole’

24. Ozone depletion has increased over time…

25. Less ozone---> > UV ---> > damage to DNA

26. 2. GH gases --> ‘greenhouse effect’

27. CO 2 emissions from coal and oil …and from clearing/burning vegetation

28. What is your ‘ecological footprint’? For every kilojoule of food energy we eat, 10 kilojoules of fossil fuel energy is required to put that food on your table. How many hectares to produce enough biological-produced fuel (ethanol) to meet our energy needs? 10.7 hectares (23 football fields!)/person Globally only 1.7 hectares of land available for each of earth’s 6 BILLION people… How many resources do you use? 30 X as many as a person in India…

29. Ecological footprints of some nations already exceed available ecological capacity.

31. Exponential growth of the human population

32. What is the carrying capacity of the globe? Doubling time of human since 1 AD When N t /N o = 2 = e rt So ln 2 = rt, t = ln2/r 0-1650 = 1650 yrs to double r =.0004 1650-1850 = 200 yrs r =.0035 1850-1930 = 80 yrs r =.0087 1930-1975 = 45 yrs r =.0152 1975-2010 = 35 yr r =.0.92 So both N and r are increasing…

33. Our survival now depends on our becoming the ‘ecological species’ and taking our proper place in the ‘Economy of Nature’.