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- 2. Water Pollution: Types, Effects, and Sources What is water pollution? Major types of pollutants, sources and
- 3. Major Categories of Water Pollutants Infectious Agents Bacteria, Viruses, Protozoa, Parasitic Worms Source: Human and animal
- 4. Pollution in Streams
- 5. Benefits of Floodplains Highly productive wetlands Provide natural flood and erosion control Maintain high water quality
- 6. Dangers of Floodplains and Floods Deadly and destructive Human activities worsen floods Failing dams and water
- 7. Before and During a Flood in St. Louis, Missouri
- 8. Oxygen released by vegetation Diverse ecological habitat Evapotranspiration Trees reduce soil erosion from heavy rain and
- 9. Tree plantation Evapotranspiration decreases Ranching accelerates soil erosion by water and wind Winds remove fragile topsoil
- 10. Reducing Flood Risks Channelization Levees (floodwalls) Dams Protect and restore wetlands Identify and manage flood-prone areas
- 11. Lake Pollution Dilution less effective than with streams Stratification in lakes and relatively little flow hinder
- 12. Oligotrophic and Eutrophic Lakes
- 13. Groundwater Pollution: Causes and Persistence Sources of groundwater pollution Slow flowing: slow dilution and dispersion Consequences
- 14. Coal strip mine runoff Pumping well Waste lagoon Accidental spills Groundwater flow Confined aquifer Discharge Leakage
- 15. Extent of Groundwater Pollution Not much is known about groundwater pollution Organic contaminants, including fuel leaks
- 16. Pump nanoparticles of inorganic compounds to remove pollutants (may be the cheapest, easiest, and most effective
- 17. Ocean Pollution How much pollution can oceans tolerate? Some pollutants degrade and dilute in oceans Ocean
- 18. Industry Nitrogen oxides from autos and smokestacks; toxic chemicals, and heavy metals in effluents flow into
- 19. Mississippi River Basin Missouri River Ohio River Mississippi River LOUISIANA Mississippi River Depleted Oxygen Gulf of
- 20. Chesapeake Bay Largest US estuary Pollution “sink” Oxygen depletion Chesapeake Bay Program
- 21. Effects of Oil on Ocean Life Crude and refined petroleum Tanker accidents and blowouts Exxon Valdez
- 22. Prevention Cleanup Ban dumping of wastes and sewage by maritime and cruise ships in coastal waters
- 23. Preventing Nonpoint Source Pollution Mostly agricultural wastes Use vegetation to reduce soil erosion Reduce fertilizer use
- 24. Laws for Reducing Point Source Pollution Clean Water Act Water Quality Act
- 25. Sewage Treatment Systems Sewage treatment in rural and suburban areas Septic tanks Primary (physical) sewage treatment
- 26. Typical Septic Tank System Household wastewater Perforated pipe Distribution box (optional) Septic tank with manhole (for
- 27. Primary and Secondary Sewage Treatment Raw sewage from sewers Bar screen Grit chamber Settling tank Aeration
- 28. Improving Sewage Treatment Systems that exclude hazardous wastes Non-hazardous substitutes Composting toilet systems Working with nature
- 29. Ecological Wastewater Treatment Burlington, VT University of Vermont
- 30. Should the Clean Water Act be Strengthened? Yes: environmentalists No: farmers, libertarians, manufacturers, and developers State
- 31. Drinking Water Quality Purification of urban drinking water Purification of drinking water in developing countries Bottled
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