1. ESM 202 Eutrophication

8. US East Coast Source: Issues in Ecology #2 (1998)

9. Gulf of Mexico Dead Zone Source: NOAA

10. Effects of Eutrophication Source: Principles Env. Sci. & Eng. (Davis & Masten)

11. Source: Issues in Ecology #2 (1998)

12. Effects of Eutrophication Source: Issues in Ecology #2 (1998)

15. Lake Ageing Source: Principles Env. Sci. & Eng. (Davis & Masten)

17. Classification of Lakes Source: Principles Env. Sci. & Eng. (Davis & Masten)

18. Probable, not certain… Eutrophic Source: Principles Env. Sci. & Eng. (Davis & Masten)

19. Total P vs. Chlorophyll a Source: Principles Env. Sci. & Eng. (Davis & Masten)

20. Classification of Lakes Source: Principles Env. Sci. & Eng. (Davis & Masten)

21. Lake Stratification Source: Principles Env. Sci. & Eng. (Davis & Masten)

22. Lake Stratification Source: Principles Env. Sci. & Eng. (Davis & Masten)

23. Diagnostics… Source: Biogeochemistry, Schlesinger, 1997

24. Diagnostics… Flux in g/m 2 yr Source: Biogeochemistry, Schlesinger, 1997

25. Diagnostics… Source: Biogeochemistry, Schlesinger, 1997

26. Analysis of Cause and Effect Low Nutrient Supply Low N & P conc. in lake Low algae productivity Low chlorophyll a Lake more transparent Greater Secchi disc depth High Nutrient Supply High N & P conc. in lake High algae productivity High chlorophyll a Lake less transparent Smaller Secchi disc depth Gradient of Conditions Toxic inflow High Sediment High Flowrate

27. Solutions… Source Reduction Eliminate excess fertilization Wastewater treatment plants BMPs In Lake Control: Mechanical harvesting of aquatic plants Chemical control (algaecides) Biological control (increase grazing) Flow augmentation Deep water aeration Selective removal of deep water Sediment removal

28. Modern wastewater treatment

29. Process Diagram

30. Modern wastewater treatment

31. Packaged wastewater treatment

32. Performance & Policies

33. Pathogen removal

34. Lagoon Treatment Systems

35. Constructed Wetland

36. Septic Systems

37. Key Points Eutrophication is a natural process Can be greatly accelerated by human activity Serious ecological effects Must use diagnostics to get at the root of the problem Point vs non-point source, magnitude and timing of load, N or P? Range of solutions depending on sources and socioeconomic choices