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Land Use

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  1. Land Use Our urban world Forestry management Parks, Reserves, and Wildlands Agricultural land use

  2. Urban environments • Created due to industrialization • Require resources from other places • Need natural land nearby for • ecosystem services: water, air, waste • escape from stresses of daily urban life • preservation for posterity

  3. Urban environments • Includes larger and larger percentages of the population 1850 – included 15% of US citizens 1920 – included more than 50% of US citizens Now – includes more than 80% of US citizens

  4. Chicago area population growth

  5. Portland area population growth

  6. Urban Sprawl • Why does this happen? • What are the positive and negative aspects of sprawl?

  7. What makes a city livable?

  8. Examples of livable cities • Chicago area • Portland area

  9. Forest management • Forests provide many resources and services • In US, management practices have changed over time

  10. Westward expansion • Development of resources – forests, minerals, rangelands • Originally there was no land use planning • Deforestation began to occur

  11. Natural forests, 1620

  12. Natural forests, 1920

  13. Natural forests today

  14. Management strategies • Clear cutting vs. selective cutting • Maximum sustainable yield • Ecosystem based management • Adaptive management • Public vs. private land

  15. US Forest Service • Gifford Pinchot • Changing mission • Timber for nation • Multiple use management • Impact of road building

  16. US Forest Service and fires • Changing opinions on management • Total suppression • Let it burn • Prescribed burns • Influence of climate change

  17. US federal parks and reserves • National parks: • Managed by National Park Service • monuments, historic sites, wild and scenic rivers, parks, and recreation areas • Too many visitors? • National forests: • Managed by US Forest Service • Timber harvests • Fire suppression

  18. US federal parks and reserves • National wildlife refuges: • Managed by US Fish and Wildlife Service • Variety of management styles • Preservation (Sevilleta NWR as example) • Active manipulation (Bosque del Apache NWR as example)

  19. Sevilleta Wildlife Refuge, NM

  20. Sevilleta Wildlife Refuge, NM

  21. Bosque del Apache Wildlife Refuge, NM

  22. Bosque del Apache Wildlife Refuge, NM

  23. Wilderness areas • Should they exist? • Changing values • Resources such as timber, oil, minerals? • States rights? • Wilderness Act of 1964 • Public lands can be set aside • No development allowed

  24. What should parks look like? • Many small or one large? • Protection of biodiversity • Wildlife corridors • What is practical?

  25. Agricultural land use • 38% of land world-wide is agriculturally used • 2/3 of this is pasture land • 1/3 of this is used for crops

  26. Crop production - feeding the world • Industrial agriculture – green revolution • Inorganic fertilizers and synthetic pesticides • Fossil fuels • Genetically modified crops • Monocultures • Removal of wetlands

  27. What about sustainable agricultural practices? • Soil management • Irrigation practices • Targeted fertilizer • Integrated pest management • No-till farming

  28. Livestock grazing • ¼ of world land • Sustainable if at low intensity – think about Tragedy of the Commons • Use of public lands

  29. Some additional agricultural issues • Feedlot agriculture (factory farming) • Aquaculture • Organic farming • Buy local movement

  30. Making cities livable • Planning and zoning • Urban growth boundaries • Smart growth • New urbanism • Transit options • Parks

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