1. UNIT 5 – LAND USE & WASTE Chapters 14 – 16, 19

2. 14.1: How We Use Land Urban—land covered mainly with buildings & roads Rural—land containing few people & large areas of open space

3. Most land provides resources that humans can use – Wood, crops, minerals

4. 14.2: Urban Land Use Urbanization—movement of people from rural areas to cities – Over 79% of U.S. is urban

5. Problems of Urban Growth Infrastructure can’t meet demands – Roads, sewers, schools, hospitals, etc. Urban sprawl—rapid expansion into the countryside – Buildings built on previous farmland

6. Development occurs on marginal land – Areas prone to landslides, erosion

7. Urban Planning Land-use planning determines how land will be used before building begins – Environmentally sensitive areas can’t be ignored Mass transit systems planned in most cities

8. Open space: land set aside within cities – Parks, hiking/biking trails – Plants in open spaces absorb CO 2 & filter pollutants from air & water

9. 14.3: Land Management Farmlands—land used to grow crops Rangelands—grasslands not used for growing crops – Commonly used for grazing livestock – Overgrazing can degrade the land

10. Forest lands—provide trees for harvest – Clear-cutting removes all trees – Selective cutting removes certain trees

11. Deforestation—clearing trees without replacing them – Reduces wildlife habitat; affects biodiversity

14. Reforestation—trees are planted to re-establish cut down trees 90% of global timber comes from forests not sustainably managed

17. Parks & Preserves Yellowstone established as first national park U.S. Wilderness Act (1964) – Designated wilderness as land & ecosystems protected from exploitation – Open to hiking, fishing, camping

18. Benefits of protected areas – Saves species – Provides recreation & research Threats to protected areas – Litter from visitors – Mining, logging, drilling close to parks

19. 15.2: Soils Topsoil—surface layer of soil – Contains living organisms, rock, water, air, & organic matter Fungi & bacteria decompose material & add nutrients to the soil

20. Land Degradation Land degradation happens when human activity or natural processes damage the land Desertification—land becomes more desertlike – Caused by overgrazing and poor crop planting practices

21. Soil Conservation Soil conservation practices prevent downhill erosion of topsoil Terracing creates small, level fields

22. Contour plowing follows the slopes of hills instead of plowing up them Vegetation strips catch soil & water

23. Enriching the Soil Modern methods of fertilizing soils include both organic & inorganic fertilizers Compost—partly decomposed organic material

24. 16.3: Mining Regulations Mining operations are heavily regulated to reduce environmental impacts

25. Impacts of Mining Air & noise pollution – Dust emissions, equipment & blasting Water contamination – Acid mine drainage forms from toxic chemicals in mines Displacement of wildlife – Habitat loss around mine areas

26. Soil degradation – Soils removed in mining lose nutrients Subsidence—sinking of ground – Due to mine collapse

27. Underground mine fires – Coal-seam fires start when coal ignites underground – Hard to extinguish

28. Mining Reclamation Reclamation—process of returning land to its original or better condition after mining State regulation of mining – Mining companies must obtain permits – Mine must be reclaimed or company is fined

29. 19.1: Solid Waste Solid waste—discarded solid material – 55% of garbage dumped in landfills Many cities running out of space to dispose of waste – Ex: the barge Mobro

30. Increasing human population causes increased garbage production – Solid waste production tripled since the 1960s

31. Types of Solid Waste Biodegradable waste—can be broken down by natural processes – Ex: plant & animal matter, newspapers, paper bags, cotton, leather

32. Nonbiodegradable waste—can’t be broken down by natural processes – Ex: plastics, electronics, polyesters Plastics eventually dissolve into small particles, cause biotoxins in food chains

33. Garbage from Japan tsunami now reaching west coast of U.S. – Plastics compose most of garbage field

34. Solid Waste Production Municipal solid waste—produced by households & businesses – Produces 2% of total solid waste Manufacturing, mining & agriculture make up most of solid waste in U.S.

35. Landfills Where solid waste goes: – 55% in landfills – 30% recycled – 15% incinerated Landfill—permanent waste-disposal facility – Wastes put in ground & covered

37. Problems With Landfills Leachate—toxic liquid that forms when water seeps through a landfill Decomposing waste produces methane gas – Can be pumped out & used as fuel

38. Safeguarding landfills – New landfills must be lined with clay & plastic liners – Must collect & treat leachate – Methane gas must be vented Landfills are filling up faster than materials decompose Incinerators burn garbage – Burned materials may be more toxic

39. 19.2: Reducing Solid Waste Reuse materials – Use dish towels, rechargable batteries Reduce waste – Buy products with less packaging

40. Recycling Products made from recycled materials save 70 – 95% of energy needed to make new products Recycling includes: – Collection & sorting – Cleaning – Reuse materials in new products

41. Benefits of composting – Removes yard waste from landfills – Provides nutrients for soil & plants – Reduces need for fertilizers

42. Changing Materials We Use Recycling products into new products eliminates waste – Ex: aluminum into siding, plastics into lawn furniture

43. Degradable plastics – Photodegradable—break down in sun – Green plastic—blend plant sugars with chemicals to make plastic Problems with degradable plastics – Degraded plastics are broken into smaller pieces, not eliminated

44. 19.3: Hazardous Waste Hazardous waste—any waste that is a risk to human health – Solids, liquids or gases that contain toxic, corrosive, or explosive materials

45. The Superfund Act Owners of hazardous waste sites who illegally dumped waste can be forced to pay for cleanup Fines help pay for clean up of other contaminated sites – Ex: Love Canal, TCAAP

46. Superfund Sites

48. Solutions to Hazardous Waste Produce less hazardous waste Treat with chemicals to make waste less hazardous Deep-well injection—wastes pumped deep into the ground below groundwater, then capped with cement

49. Household Hazardous Waste Common household hazardous waste – Ex: paint, pesticides, batteries, cleaners Products should be disposed of at household hazardous waste facilities People illegally dispose of 185 million gallons of oil each year