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Land, public and private

Chapter 10. Land, public and private. Land Use Affects the Env. Tragedy of commons – tendency for a shared, limited resource to become depleted because people look for short-term gain Overgrazing, deforestation, overfishing, pollution…

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Land, public and private

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  1. Chapter 10 Land, public and private

  2. Land Use Affects the Env • Tragedy of commons – tendency for a shared, limited resource to become depleted because people look for short-term gain • Overgrazing, deforestation, overfishing, pollution… • Externality is a cost or benefit of a good or service that is not included in the purchase price of that good, usually to a third party (byproduct) • Buy a car, what costs come along with it (pros or neg) • Factory sends waste into a river • Farming (greenhouse gases, resistance bacteria, water poll.) • Maximum sustainable yield – the max amount of a renewable resource that can be harvested without compromising the future availability of the resource • Remove select trees to allow just enough light onto young trees. Remove too many, forest dries out • Fishing, hunting

  3. Public Land Classification • International public lands (6) • National parks – used for scientific, educational, and recreational use. Not used for extraction of resources • Managed resource protected areas – used for biological, mineral, and recreational resources • Habitat/species management areas – managed to maintain biological communities (prevent predators) • Wilderness areas – established to protect species and ecosystems . Minimal env impacts. No development • Protected landscapes and seascapes – used for resources and tourism without destructing place • National monuments – areas set aside for special natural or cultural interest

  4. US Public land • National forests – protected lands, but can be used for recreation vehicles, logging, hunting • National parks – used for scientific, educational, recreational, and aesthetic use • Set aside to protect ecosystem for future • Not hunting, fishing, logging • National wildlife refuges are set aside for protecting specific wildlife • Wilderness areas are left in their natural state. Protect ecosystems. Mostly used only for scientific study

  5. Biosphere reserves = land with exceptional biodiversity

  6. Land Management • Rangelands are dry, open grasslands used for grazing • Overgrazing can lead to loss of vegetation, soil erosion, water pollution, exotic species, and food shortages • Rotate animals, minimize numbers, herbicides, prescribed fires (kill weeds and create new, fresh grass) • Forests are areas dominated by trees • Clear cutting removes all the trees in one area. • Cheapest and easiest. Increases erosion and hurts habitats • Selective cutting removes individual trees. • More expensive and take good trees, but protects habitats • Tree plantations are when forests are replanted with quick growing trees. • Allows a lot of a desirable trees, customize soil/water • Never allows forest to mature, reduces biodiversity, one type of wood • Fire management – allows for nutrient cycling, land clearing, and early succession species

  7. The entire eastern half of the continent used to be covered in primary forest Most primary forest was cut for agriculture and timber

  8. Forests • Forests are some of the richest ecosystems for biodiversity • They are structurally complex, with many niches • They provide food and shelter for multitudes of species • Fungi and microbes have parasitic and mutualistic relationships with plants • Plant diversity leads to greater overall organism diversity • Succession changes species composition • Old-growth/primary forest diversity exceeds that of secondary and plantation forests

  9. Forests cover 31% of Earth’s surface

  10. Forests provide ecosystem services • Forests provide cultural, aesthetic, health, and recreation values • Forests also provide vital ecosystem services • Stabilize soil and prevent erosion • Slow runoff, prevent flooding, purify water • Store carbon, release oxygen, influence weather patterns, and moderate climate • Roots draw minerals to surface soil layers • Plants return organic material to the topsoil as litter • Forests store large amounts of carbon which limit climate change • They provide medicines, food, fuel, shelter, ships, paper

  11. Harvesting Trees • Building roads into previously inaccessible forests paves the way for fragmentation, destruction, and degradation.

  12. Harvesting Trees Effects of clear-cutting in the state of Washington, U.S. Figures 10-10 and 10-11

  13. Sustainable Forestry • Identify and protect forest areas high in biodiversity • Grow more timber on long rotations • Rely more on selective cutting and strip cutting • Stop clear-cutting on steep slopes • Cease logging of old-growth forests • Prohibit fragmentation of remaining large blocks of forest • Sharply reduce road building into uncut forest areas • Leave most standing dead trees and fallen timber for wildlife habitat and nutrient recycling • Include ecological services of forests in estimating their economic value • Plant tree plantations on deforested and degraded land • Shift government subsidies from harvesting trees to planting trees

  14. The National Forest Management Act (1976) • Every national forest must formulate plans for renewable resource management that: • Consider both economic and environmental factors • Provide for and protect regional diversity • Ensure research and monitoring of management • Permit only sustainable harvest levels • Ensure that profit alone does not guide harvest method • Protect soils and wetlands • Assess all impacts before logging to protect resources

  15. Federal Regulation of Land Use • National Environmental Policy Act (NEPA) mandates an env assessment of all projects involving federal money. The following steps • Environmental Impact Statements (EIS) is an outline to the project. Looks at env contexts and suggests alternative approaches • Environmental Mitigation Plans describe how a project will address environmental impacts • Endangered Species Act • Wilderness act

  16. Residential Land Use • Suburban areas surround metropolitan areas and have relatively low population densities. Fastest growing areas • Urbanization is when people move into cities • Urban sprawl is when populations shift into suburban areas (clusters of houses, retail shops) • Use twice as much land per person as urban areas, more driving, pushes farmland away increasing the distance • 4 main causes of urban sprawl • Automobiles/highways make for easy access • Living costs (more for your money) • Urban blight (areas becoming abandoned) • Gov Policies

  17. Problems with Urban Sprawl • Economists, politicians, and city boosters think growth is always good • Transportation: people are forced to drive cars • Pressure to own cars and drive greater distances • Lack of mass transit options • More traffic accidents • Increases dependence on nonrenewable petroleum • Pollution = carbon dioxide, air pollutants, ozone, smog, acid precipitation • Motor oil and road salt from roads and parking lots

  18. Continued • Health = sprawl promotes physical inactivity because driving cars replaces walking • Increases obesity and high blood pressure • Land use = less forests, fields, farmland, or ranchland • Loss of resources, recreation, beauty, wildlife habitat, air and water purification, services • Economics: sprawl drains tax dollars from communities • For roads, water and sewer systems, electricity, police and fire services, schools, etc. in new areas • Taxpayers, not developers, subsidize improvements

  19. Continued • Noise pollution = undesired ambient sound • Degrades surroundings, stressful, hurts hearing • Light pollution = lights obscure the night sky • Impairing the visibility of stars, affecting nocturnal animals • Urban heat island effect = cities are hotter than surrounding areas • Buildings, vehicles, factories, and people generate heat • Dark buildings and pavement absorb heat

  20. People in suburbs take up lots of space Even in metro areas where population decreases, the amount of land covered increases

  21. Several types of development lead to sprawl

  22. Urban Planning • Limit sprawl: keeps growth in existing urbanized areas • Revitalize downtowns • Protect farms, forests, and industries • Ensure urban dwellers some access to open space • May reduce infrastructure costs • Disadvantages: • Increase housing prices within their boundaries • Restrict development outside the urban growth boundary (UGB) • Increase the density of new housing inside the UGB • Increasing pressure to expand boundaries

  23. Smart Growth • Smart Growth: A city planning concept in which a community’s growth is managed in ways that limit sprawl and maintain of improves residents’ quality of life. It involves guiding the rate, placement, and style of development such that it serves the environment, the economy and the community. • Proponents of smart growth promote: • Healthy neighborhoods and communities • Jobs and economic development • Transportation options • Environmental quality • Building “up, not out” • Focusing development in existing areas • Favoring multistory shop-houses and high-rises

  24. Transportation Options • Traffic jams cause air pollution, stress, and lost time • Cost the U.S. economy $74 billion/year • Key in improving quality of urban life: mass transportation • Buses, trains, subways • Light rail = smaller systems powered by electricity • Cheaper, more energy efficient, and cleaner • Traffic congestion is eased

  25. Establishing mass transport is not easy • It is expensive to replace existing roads • Strong, visionary political leadership is needed • Growth is directed, instead of being overwhelming • Governments can encourage mass transit • Raise fuel taxes • Tax inefficient modes of transport • Reward carpoolers • Encourage bicycle use and bus ridership • Charge trucks for road damage • Stimulate investment in renewed urban centers

  26. Greenways: A strip of parkland that connects parks or neighborhoods; often located along rivers, streams or canals. • Greenbelts are long, wide corridors of parklands • May surround an entire urban area • Green buildings = structures that reduce their ecological footprints • Built from sustainable materials, minimize energy and water use, recycle wastes

  27. 10 Principles of Smart Growth • Strategies for healthy and sustainable communities • Mixed land use encourages people to walk/bike • Create a range of housing choices (for diff incomes) so all people can find a job nearby • Create walkable neighborhoods (buildings near sidewalks, slow speed limits, etc) • Encourage stakeholders to collaborate in decisions • Take advantage of compact building design • Create a feeling of a sense of place • Preserve open space • Provide a variety of transportation services • Fill vacant areas before new development • Make development decisions predictable and fair

  28. http://www.ted.com/talks/lang/en/john_kasaona_from_poachers_to_caretakers.htmlhttp://www.ted.com/talks/lang/en/john_kasaona_from_poachers_to_caretakers.html

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