soil and land pollution rad guide ch 18 19 n.
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Soil and Land Pollution RAD Guide (Ch.18-19)

Soil and Land Pollution RAD Guide (Ch.18-19)

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Soil and Land Pollution RAD Guide (Ch.18-19)

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  1. Soil and Land Pollution RAD Guide (Ch.18-19) September 20, 2014

  2. What are 2 ways that exposed rock can be weathered? • Mechanically • Example: waves on a cliff • Chemical • Example: rusting

  3. What is bedrock? Why is it important to soil formation? • Bedrock: igneous, metamorphic, and sedimentary rock of lithosphere that may exist as mountains, cliffs, or low-lying plains • Supplies material needed to build soil

  4. Describe what soil is and how is formed. • Soil: mixture of mineral particles, air, H2O, & living and decaying organisms • Outer layer of bedrock weathers (cracks and holes) • Cracks reach deeper & outer layer becomes broken into small particles • Burrowing animals & plant roots break down bedrock & aerate soil VOCAB: parent rock

  5. Describe what a soil profile is and what 4 distinct layers form. • Soil profile: a vertical cross section of soil from the ground surface down to the bedrock • A Horizon: topsoil • B Horizon: subsoil • C Horizon: parent rock • R Horizon: bedrock

  6. Describe the 3 major soil textures. • Sandy: enables soil to drain well but dries out quickly; largest mineral size • Clay: flat and traps H2O, preventing H2O drainage; smallest mineral size • Loam: mixture of sizes for good drainage and moisture for plants; medium mineral size

  7. Describe the interaction of soil & climate. • Desert: small soil profile; large particles • Grasslands: thicker soil profile; faster weathering of rock • Tropical: very thick soil profile; very fragile soil because of so much rain; a lot of clay in the subsoil

  8. What are the major causes of erosion? • Wind and running water

  9. What causes soil loss & desertification? What % has undergone desertification? • Overgrazing, deforestation, & poor irrigation and cultivation • 30%

  10. How much topsoil is lost to water & wind erosion? • 2.5 billion tons lost to water • 1.5 billion tons lost to wind • TOTAL=4 billion metric tons!

  11. Describe the 4 types of soil conservation & land management. • Strip-cropping: farmland plowed so plowed strips separated by planted strips • Contour Farming: plowing along a slope instead of across it; furrows collect H2O which reduces erosion

  12. Terracing: series of platforms (terraces) are built into the slope; separated by vertical steps • Shelter belts: rows of trees planted along outer edges of field

  13. How do we define solid wastes? • All garbage, refuse, & sludge products from agriculture, forestry, mining, and municipalities • Examples: garbage trash junk sewage scrap refuse

  14. Describe how garbage disposal has changed over the years. • Hunter-gatherers: left it and moved on • Athens, Greece 500BCE: trashed dumped outside of city walls • Rest of Europe dumped in the streets • NYC/NJ 1892-1900CE: garbage loaded onto ships and dumped in Atlantic Ocean • Now we use landfills

  15. What is a landfill? How much garbage is dumped there? • Site where wastes are disposed of by burying them • 70%

  16. Why are open landfills no longer allowed in the US? • It supported large populations of rats, insects, etc. • Foul odor and disease

  17. Describe what a sanitary landfill is & identify 2 problems. • Wastes are spread in layers ~3m deep & compacted by bulldozers • Soil spread on top of refuse & compacted • Repeated until garbage reaches certain heights • Methane produced • Leaching of toxic substances

  18. What are hazardous wastes? • Solid, liquid, or gaseous wastes that are potentially harmful to humans and environment • Love Canal, NY: Town built next to old chemical plant • Steel containers holding waste leaked • Birth defects and cancer affected the people • Government relocated them ($190 million)

  19. Name 6 types of hazardous waste. • Reactive Waste: can explode • Corrosive Waste: can eat through steel, clothing, and burn skin • Ignitable Waste: can burn at low temp; toxic fumes when lit • Toxic Waste: chemicals that are poisonous to people • Radioactive Waste: gives off radiation (given off when mining Uranium) • Medical Waste: old medicine, medicine containers, lab equipment and specimens

  20. Identify & explain 4 methods for reducing volume of waste. • Recycle: paper, plastic, aluminum, glass, etc. • Reuse: cloth diapers • Biodegradable: leaves, grass clippings, food waste*, composting • Repair: old appliances, shoes, cars

  21. Name 6 ways of disposing of hazardous waste. • Waste exchange: use haz. waste in production of other materials • Deep Well Injection: inject waste into porous rock under water table; LIQUID • Secure Chem. Landfill: waste is stored on nonporous bedrock • pipes to monitor and collect leaks; cover with clay

  22. Controlled Incineration: burn waste at high temp • Expensive • Biological and Chemical Treatment Plants: turn harmful things into harmless • Radioactive Waste Disposal: put in H2O or bury underground

  23. What does EPA stand for? • EPA = Environmental Protection Agency • Established in 1970

  24. Briefly describe Superfund. • Law designed to protect communities from dangers of hazardous wastes • CERCLA (1980): got $9 billion dollars to implement

  25. What are some countries doing to combat high cost of disposal? • Ship waste to developing nations and leave it there • Examples: West Africa and Zimbabwe