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Chapter 23 Lecture

What are the Major Types of U.S. Public Lands?. Multiple Use LandsNational Forest SystemNational Resource Lands. Moderately Restricted-Use Lands National Wildlife RefugesRestricted-Use Lands National Park SystemNational Wilderness Preservation System. How Should U.S. Public Lands Be Managed?.

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Chapter 23 Lecture

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    1. Chapter 23 Lecture Sustaining Aquatic Biodiversity

    2. What are the Major Types of U.S. Public Lands? Multiple Use Lands National Forest System National Resource Lands. Moderately Restricted-Use Lands National Wildlife Refuges Restricted-Use Lands National Park System National Wilderness Preservation System

    3. How Should U.S. Public Lands Be Managed? The four following principles from environmental economists and free-market economists: (Aldo Leopold’s Land Ethics) Protect biodiversity, habitats, and ecological functioning should be number 1 goal. No one should receive subsidies or tax breaks for using or extracting resources on public lands. American people deserve fair compensation for the use of their property. All users of extractors of resources on public lands should be fully responsible for any environmental damage caused.

    4. How Should U.S. Public Lands Be Managed? Economists, developers, and resource extractors view public lands in the following ways: Their usefulness in providing mineral, timber, and other resources The ability to increase short-term economic growth Encourage the US Congress to pass a variety of anti-environmental laws

    5. What Are the Major Types of Forests? Forests with 50% or more tree cover occupies about 32% of the earth’s land surface Can be classified as: Old-Growth Forests – uncut forests or regenerated forests that have not been seriously disturbed by human activities or nature disasters Second-Growth Forests – stands of trees from areas where trees were once removed by human activities such as clear cutting or natural forces such as fire, hurricanes, or volcanic eruptions. Tree Plantations – managed tracts with uniformly aged tress of one species.

    6. What Are the Major Types of Forest Management? Even-aged Management – involves maintaining trees in a give stands at about the same size and age. Uneven – aged Management – involves the maintaining of a variety of species in a stand at many ages and sizes to foster natural regeneration. Goals of Biological diversity Long-term sustainable production Selective cutting of individual or mature trees Multiple use of the forest

    7. How Are Trees Harvested? Build roads for access and timber removal: Increased erosion and sediment runoff Habitat fragmentation and biodiversity loss Exposure of forests to invasion by nonnatives Opening of once-inaccessible forests to farmers, miners, etc. Logging roads cannot be protected as wilderness.

    8. How Are Trees Harvested? Selective cutting – cut singly or in small groups Reduced crowding Encourages growth of younger trees Maintains an uneven-aged stand or different species. Allows natural regeneration from the surrounding trees Can be used to remove diseased tress Can protect the site for soil erosion and wind damage Allows a forest to be used for multiple purposed. High-grading – the cutting and removing of only the largest and best. Reduces the forest canopy Causes the forest floor to become warmer, drier, and more flammable. Increases erosion of the forest’s thin and nutrient-poor soil

    9. How Are Trees Harvested? Shelterwood Cutting - removes all mature trees in two to three cuttings over a period of ten yeas. Seed-tree Cutting – harvests nearly all a stand’s trees in one cutting, leaving a few uniformly distributed seed-producing trees Clear-cutting – removes all of the trees from an area in a single cutting. Strip-cutting – clear-cutting a strip of trees along the contour of the land to allow natural regeneration within a few years

    10. Positive and Negative Sides of Clear Cutting POSITIVE: Increases timber yield per hectare Permits reforesting with genetically improved stocks Shortens time to establish a new stand of trees Takes less skill and planning Maximum economic return in the shortest time. If done carefully and responsibly is the best way to harvest tree plantations for some species. NEGATIVE: Leaves moderate to large forest openings Eliminates most recreational value for decades Disrupts biodiversity; destroys and fragments wildlife habitat Makes nearby trees more vulnerable to being blown down Leads to severe soil erosion, sediment water pollution, and flooding on steep slopes.

    11. What Is Happening to the World’s Forests? Forests are renewable resources as long as the rate of cutting and degradation does not exceed the rate of regrowth. How Can Forests Be Managed More Sustainably? Grows timber on long rotations Emphasizes selective cutting, strip cutting, not clear-cutting on steep slopes Minimize fragmentation Reduce road building in uncut forest areas Use road building and logging methods that minimize soil erosion and compaction. Leave most standing dead trees and fallen timber Timber grown by sustainable methods certified and labeled by outside certifying groups Includes the estimated ecological services in economic value.

    12. How Can Pathogens and Insects Affect Forests Ways to reduce the impact of tree diseases and of insects on forests Preserve biodiversity Ban imported timber Remove infected and infested trees, clearing, burning Treating diseased trees with antibiotics Developing tree species that are disease-resistant Applying pesticides Using integrated pest management.

    13. How Can Fires Affect Ecosystems? Fires can be important: Maintain the vegetations of many ecosystems at a certain stage of ecological succession; fires burn away the low-lying vegetation and small trees; a burst of new vegetation follows. Surface fires – usually burn only undergrowth and leaf litter on the forest floor. Kill seedlings and small trees but spare most mature trees and allow most wild animals to escape. Crown fires – extremely hot fires might start on the ground, but eventually burn whole trees and leap from top to top.

    14. How Can We Protect Forests From Fire? Prevention Requiring burning permits Closing all parts of a forest and camping during periods of drought and high fire danger Educating the public Smokey Bear! – prevent forest fires, save lives, prevent billions in losses Prescribed burning – setting controlled ground fires Presuppression – early detection and control of fires Suppression – fighting fires once they have started.

    15. How Do Air Pollution and Climate change Threaten Forests? At high elevations and those downwind from urban and industrial centers are exposed to a variety of air pollutants that can harm trees Reduce emissions of the offending pollutants Regional climate change brought about by global warmning Increase the threat of forest fires in areas that may get less precipitations Cause some types of tree species to die out in some areas.

    16. Why Should We Care About National Forests? Economic Supply timber Serve as grazing lands Provide minerals, oil, and natural gas Contain network of roads Ecological o Provide habitat for almost 200 threatened and endangered species o Principle habitats for pollinator species o Provide some of the cleanest drinking water. Recreational Recreation, hunting, fishing

    17. How Should U.S. National Forests Be Managed? Sustainable Yield – trees can’t be harvested or used faster than they are replenished Multiple Use – each of the forests should be managed for a variety of uses such as sustainable timber harvesting, recreation, livestock grazing, watershed protection, and wildlife. In 2001, Bush increased the sale of timber in national forests by 40%, moved to block road construction in roadless areas of the national forest; eliminated the requirement that the forest service manage national forests to protect the viability of wildlife and ecological sustainability. Created the idea of charter forests.

    18. Battle Between Environmentalists and Timber Companies Environmentalists: Timber-cutting program Loses Money: Logging in national forests causes more harm than good to local communities near such forests; Communties relying on national forest timber sales experience economic slumps. Costs the taxpayers in logging subsidies and cleaning of pollutions; It would save taxpayers money. Only provides about 3% of the countries wood is from National Forests Ample private forestland is available to meet the countries demand for wood Below costs is not good for other forests and has little effect on the consumer Recreation in national forests provides more jobs. Timber Companies say: Helps satisfy the country’s demand for food Provides cheap timber that benefits consumers Improves forest health, fires Provides jobs and stimulates economic growth.

    19. How Can We Cut Fewer Trees by Using Wood More Efficiently? 60% of the wood consumed is wasted: o inefficient use of construction materials o excess packaging o Overuse of junk mail o Inadequate paper recycling Failure to reuse wooden shipping containers o Packaging (50%) o Writing and printing (30%) o Newsprint (12%) o Paper tissues and towels (8%) Only 3% of softwood production comes from national forests

    20. How Can We Cut Fewer Trees by Making Paper from Tree-Free Fibers? Tree-free fibers: From agricultural residues from crops From fast growing crops Account for 7% of the world’s fiber supply for paper less than 1% in the US China uses tree-free pulp – makes 60% of paper Made from kenaf in the US 3 – 5X the cost – however, supply and demand

    21. Why Is It Difficult to Determine Deforestation? Interpretation of satellite images Different ways of defining forests Political and economic factors Why Should We Care About Tropical Forests? Economic and ecological services Their instrumental values Chemicals Uses

    22. Case Study: Madagascar 85% of the plant and animals species re endemic species unique to the island Lost of habitat due to slash and burn agriculture and rapid population growth Many species face extinction Large erosion

    23. What Is Cultural Extinction? Indigenous cultures who used the land sustainably are vanishing This is an irreplaceable loss of ecological knowledge and cultural diversity They know how to live sustainably They know which plants are useful as food and medicines.

    24. Solutions to Deforestation and Degradation Solutions: New settlers who know how to practice small-scale sustinable agriculture and forestry Debt for Nature Swaps Conservation Easements Conservation Concessions International System for Evaluating Timber produced by sustainable methods Gentler methods for harvesting trees National and global efforts to reforest and rehabilitate

    25. Fuelwood Crisis Developing countries use wood to meet their energy needs They have not had enough to meet their needs They burn charcoal because it is lighter and cheaper They must travel far distances, expensive, more disease, burn dung and crop residues Solutions: Plant more fast growing fuelwood trees Switch to other fuels (root-fuel plants)

    26. How are Parks Threatened? Only 1% of the parks in developing countries receive protections - become “paper parks” Popularity Lack of Funds Lack of law enforcement Suffer from nonnative specie Nearby human activity threatens wildlife and recreational values

    27. How Can Management of US Parks Be Improved? Currently under the principle of “Natural Regulation” - managed as if they are wilderness ecosystems that can adapt and sustain themselves. Goals and Ideas: Preserve nature Make parks available to the public, but limit visitors and raise entry fees Require integrated management plans for parks Increase the budget - more maintenance and repairs, more park rangers at higher pay Encourage donations, ask for volunteers Provide transportation Give private concessionaries

    28. What Principles Should Be Used to Establish and Manage Nature Reserves? Ecosystems are rarely stable Ecosystems and communities that experience fairly frequent but moderate disturbances have the greatest diversity of species We should view most at habitat islands.

    29. How Should Nature Reserves Be Designed? Shape - Circular or Elongated? Single Large or Several Small Reserves? Heterogenous or Homogeneous? Isolated or Connected What about Buffer Zones?

    30. What is Gap Analysis? Gap Analysis - determines whether existing networks or nature reserves provide enough protection for native plant and animal species. Maps of topography Databases of biological information Superimpose the species data onto the maps Use this information to close gaps Conservation Gaps - where there is a lack of adequate protection.

    31. What Areas Should Receive Top Priority for Establishing Reserves? 25 Hot Spots Mostly tropical forests Contain 60% of the biodiversity

    32. Wilderness - Why Preserve It? Wilderness - areas of undeveloped land affected primarily by the forces of nature, where man is a visitor who does not remain. Why preserve? Beauty of nature! Just to know it is there is comforting Centers of evolution Undisturbed areas A natural laboratory Wild species have a right to exist and play their roles in earth.

    33. Fixing Ecosystems Restoration - trying to return it to its predegraded state Let nature do most of the work Remove pollutants, add nutrients, add topsoil, remove nonnative species Reintroduce species Prevention from further damage Monitor area Difficulties include Lack of knowledge about previous composition Changes in climate Ecosystem is changing Rehabilitation - an attempt to restore some of the degraded system’s species and ecosystem functions. Replacement - replace a degraded ecosystem Create Artificial Ecosystems

    34. What Are The Next Steps? Preserve hot spots Keep forests intact Cease all logging of old-growth forests Concentrate on protecting lakes and river systems Determine marine hot spots Continue to map the world’s biodiversity Make conservation profitable

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