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Land Use

Land Use. Chapter 10: Forests. Central Case: Battling over the last big trees. In 1993, protestors blocked loggers from cutting ancient trees on Vancouver Island, British Columbia Most of Canada’s old-growth temperate rainforest is already gone

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Land Use

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  1. Land Use Chapter 10: Forests

  2. Central Case: Battling over the last big trees • In 1993, protestors blocked loggers from cutting ancient trees on Vancouver Island, British Columbia • Most of Canada’s old-growth temperate rainforest is already gone • 20% of the jobs depends on the timber industry Both sides struck a deal allowing environmentally friendly practices and encouraging ecotourism

  3. MANAGING AND SUSTAINING FORESTS • Forests provide a number of ecological and economic services that researchers have attempted to estimate their total monetary value. • 30% of all land mass Figure 10-4

  4. Types of Forests • Old-growth forest: uncut or regenerated forest that has not been seriously disturbed for several hundred years. • 22% of world’s forest. • Hosts many species with specialized niches. Figure 10-5

  5. Secondary Growth Forests • Second-growth forest: a stand of trees resulting from natural secondary succession • After clear-cutting • After natural processes • Weather • Fire • Wind • Ice

  6. Types of Forests • Tree plantation: planted stands of a particular tree species. • What would “H” be? Figure 10-6

  7. Resources are vital to us • We need to carefully manage the limited resources we take from the natural world • Resource management = the practice of harvesting potentially renewable resources in ways that do not deplete them • Resource managers are influenced by political, economic, and social factors • A key question is whether to focus on the resource of interest or to look more broadly at the entire environmental system

  8. Natural resources are vital to us • We need resources • Soils: agriculture, natural communities • Water: drinking, agriculture, wildlife • Wildlife and fisheries: game, nongame, and marine species • Rangeland: livestock • Minerals: mined nonrenewable resources

  9. Maximum sustainable yield Reducing populations so drastically affects other species and can change the entire ecosystem • Maximum sustainable yield = aims to achieve the maximum amount of resource extraction • Without depleting the resource from one harvest to the next • Populations grow most rapidly at an intermediate size • Population size is about half its carrying capacity • Managed populations are well below what they would naturally be

  10. Ecosystem-based management • Ecosystem-based management = managing the harvesting of resources to minimize impact on the ecosystems and ecological processes • Carefully managing ecologically important areas • Considering patterns at the landscape level • Protecting some forested areas • It is challenging for managers to determine how to implement this type of management • Ecosystems are complex, and our understanding of how they operate is limited

  11. Adaptive management evolves and improves • Adaptive management = systematically testing different management approaches and aiming to improve methods • Monitoring results and adjusting methods as needed • A fusion of science and management • Time-consuming and complicated • The 1994 Northwest Forest Plan resolved disputes between loggers and preservationists over the remaining old-growth temperate rainforests in the continental U.S. • Allowed limited logging • Protected species and ecosystems • Science-guided management in Oregon, Washington, and California

  12. Forest Management • Forests cover over 30% of Earth’s land surface • Provide habitat, maintain soil, air, and water quality, and play key roles in biogeochemical cycles • Provide wood for fuel, construction, paper production • Foresters, professionals who manage forests through the practice of forestry, must balance ecosystem services with demand for wood products

  13. Ecological value of forests • One of the richest ecosystems for biodiversity • Structural complexity houses great biodiversity • A forest provides many ecosystem services • Stabilizes soil and prevents erosion • Slows runoff, lessens flooding, purifies water • Stores carbon, releases oxygen, moderates climate

  14. Economic value of forests In 2005, over 1/3 all forests were designated for timber production • Benefits: fuel, shelter, transportation (boats), paper • Helped society achieve a high standard of living • Logging Locations: • Boreal Forests: Canada, Russia • Rainforests: Brazil, Indonesia • Conifer Forests/Pine Plantations: U.S.

  15. Demand for wood leads to deforestation Developing countries boost their economies and get land for their growing populations by logging forests • Deforestation = the clearing and loss of forests • Alters landscapes and ecosystems • Degrades soil • Causes species decline and extinction • Ruins civilizations • Adds carbon dioxide to the air

  16. Deforestation in America and Canada • Deforestation propelled the westward expansion and growth of America and Canada • Eastern deciduous forests were the first to be logged for farms and to build cities (i.e., Chicago) • Timber companies moved south to the Ozarks and west to the Rockies

  17. Loggers moved westward, searching for large trees • Primary forest = natural forest uncut by people • Little remained by the 20th century • Second-growth trees = grown to partial maturity after old-growth timber has been cut

  18. Loggers lose their jobs with deforestation • As each region is deforested, the timber industry declines and moves on • Local loggers lose their jobs • Once the remaining ancient trees of North America are gone, loggers will once again lose jobs • Companies will simply move to another area • The scarcity of remaining old-growth trees fuels scientific concerns and empassions environmentalists

  19. Deforestation is proceeding rapidly worldwide • Uncut tropical forests still remain in many developing countries • Technology allows for even faster exploitation • Deforestation is rapid in places such as Brazil and Indonesia • Developing countries are so desperate for economic development, they have few logging restrictions • Short-term economic benefits go to foreign multinational corporations • Governments often help companies, at the expense of native people

  20. “Timber famine” fears spurred forest protection • National forest system = a system of forest reserves and public lands • To grow trees, produce timber, protect watersheds, and ensure future timber supplies • Resulted from depletion of U.S. forests and fear of a “timber famine” • 77 million ha (191 million acres); 8% of the U.S. land area • The U.S. Forest Service was established in 1905 • Manage forests for the greatest good of the greatest number in the long run, including logging

  21. Federal agencies own land in the U.S.

  22. Timber is extracted from public and private land • Timber is extracted by private companies, even on public land • Forest Service employees plan and manage timber sales and build roads • The companies log and sell the timber for profit

  23. Most logging occurs on private land • But, millions of cubic feet per year are still logged from national forests • Timber harvesting remains stable in developed countries • Timber companies manage forests according to the maximum sustained yield approach • Management on public lands reflects economic forces, along with social and political ones • These change over time • Public concern, changing management philosophies and economics caused harvests to decrease

  24. Plantation forestry • The timber industry focuses on timber plantations • Fast-growing species • Monocultures • Even-aged trees = all trees are the same age • Trees are cut at the end of the rotation time and replanted • Plantations are crops, not functional forests • Some harvesting methods maintain uneven-aged (mixed ages of trees and species) tree stands

  25. Harvesting timber: clear-cutting • All trees in the area are cut • Most cost-efficient • Greatest impact on forest ecosystems • May mimic some natural forms of disturbance • Destroy entire communities • Soil erosion • Public is outraged over this type of harvesting

  26. Harvesting: other methods • Seed-tree cutting = a small number of seed-producing trees are left standing to reseed the area • Shelterwood cutting = a small number of trees are left to provide shelter for the seedlings • Selection systems = only select trees are cut • Single tree selection = widely spaced trees are cut • Group tree selection = small patches of trees are cut • All methods disturb habitat • Change forest structure and composition • Increase erosion, siltation, runoff, flooding, landslides

  27. Public forests can be managed for many things • Increased public awareness caused people to urge changed forest management • For recreation, wildlife and ecosystem integrity, instead of logging • Critics protested federal subsidies of logging companies • Multiple use policy = national forests were to be managed for recreation, habitat, minerals and other uses • In reality, timber production is the primary use The Forest Service loses $100 million/yr by selling timber below cost

  28. Harvesting forests

  29. Harvesting Trees Building roads into previously inaccessible forests paves the way for fragmentation, destruction, and degradation. Figure 10-8

  30. Harvesting Trees Trees can be harvested individually from diverse forests (selective cutting), an entire forest can be cut down (clear cutting), or portions of the forest is harvested (e.g. strip cutting). Figure 10-9

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

  32. Controversy over Logging in U.S. National Forests • There has been an ongoing debate over whether U.S. national forests should be primarily for: • Timber. • Ecological services. • Recreation. • Mix of these uses. Figure 10-14

  33. Solutions: Reducing Demand for Harvest Trees • Tree harvesting can be reduced by wasting less wood and making paper and charcoal fuel from fibers that do not come from trees. • Kenaf is a promising plant for paper production. Figure 10-15

  34. American Forests in a Globalized Economy • Timber from tree plantations in temperate and tropical countries is decreasing the need for timber production in the U.S. • This could help preserve the biodiversity in the U.S. by decreasing pressure to clear-cut old-growth and second-growth forests. • This may lead to private land owners to sell less profitable land to developers. • Forest management policy will play a key role.

  35. CASE STUDY: FOREST RESOURCES AND MANAGEMENT IN THE U.S. • U.S. forests cover more area than in 1920. • Since the 1960’s, an increasing area of old growth and diverse second-growth forests have been clear-cut. • Often replace with tree farms. • Decreases biodiversity. • Disrupts ecosystem processes.

  36. The National Forest Management Act (1976) • Mandated that plans for renewable resource management had to be drawn up for every national forest • Guidelines included: • Consideration of both economic and environmental factors • Provision for species diversity • Ensuring research and monitoring • Permitting only sustainable harvests • Protection of soils and wetlands • Assessing all impacts before logging to protect resources

  37. New forestry management is under attack • Calls for timber cuts that mimic natural disturbances • Harvesting methods are based on ecosystem approaches • The Bush administration has rolled back these regulations • Freed managers from requirements of the Act • Loosened environmental protections • Repealed President Clinton’s roadless rule, which protected 31% of national forests from road building • California, Oregon, and New Mexico have sued the government to reinstate the roadless rule

  38. Fire policy also stirs controversy • For over 100 years, the Forest Service suppressed all fires • But many ecosystems depend on fires • Fire suppression allows woody accumulation, which produces kindling for future fires • Which are much worse • Housing development near forests and climate change will increase fire risk

  39. Types and Effects of Forest Fires • Depending on their intensity, fires can benefit or harm forests. • Burn away flammable ground material. • Release valuable mineral nutrients. Figure 10-13

  40. Solutions: Controversy Over Fire Management • To reduce fire damage: • Set controlled surface fires. • Allow fires to burn on public lands if they don’t threaten life and property. • Clear small areas around property subject to fire.

  41. Solutions: Controversy Over Fire Management • In 2003, U.S. Congress passed the Healthy Forest Restoration Act: • Allows timber companies to cut medium and large trees in 71% of the national forests. • In return, must clear away smaller, more fire-prone trees and underbrush. • Some forest scientists believe this could increase severe fires by removing fire resistant trees and leaving highly flammable slash.

  42. Prescribed fires are misunderstood • Prescribed (controlled) burns = burning areas of forests under carefully controlled conditions • Effective • May get out of control • Impeded by public misunderstanding and political interference • Healthy Forests Restoration Act (2003) = promotes removal of small trees, underbrush and dead trees • Passed in response to forest fires

  43. How Would You Vote? Do you support repealing or modifying the Healthy Forests Restoration Act of 2003? • a. Yes. Local officials and scientists are probably most qualified to manage their local forests. • b. No. The initiative favors the timber companies rather than effectively protecting and managing the forests.

  44. Salvage logging • Removal of dead trees following a natural disturbance • Seems logical, but is really destructive • Snags (standing dead trees) provide nesting cavities for countless animals • Removing timber from recently burned areas increases erosion and soil damage • Promotes future fires • Increases commercial logging in national forests • Decreases oversight and public participation

  45. Sustainable forestry is gaining ground • Sustainable forestry certification = only products produced sustainably can be certified • International Organization for Standardization (ISO), Forest Stewardship Council (FSC) have different standards • Consumers look for logos to buy sustainably produced timber • Companies such as Home Depot sell sustainable wood • Encourages better logging practices

  46. Global Outlook: Extent of Deforestation Human activities have reduced the earth’s forest cover by as much as half. Losses are concentrated in developing countries. Figure 10-7

  47. Case Study: Deforestation and the Fuelwood Crisis • Almost half the people in the developing world face a shortage of fuelwood and charcoal. • In Haiti, 98% of country is deforested. • MIT scientist has found a way to make charcoal from spent sugarcane. • Unsustainable activity

  48. Solutions • We can use forests more sustainably by emphasizing: • Economic value of ecological services. • Harvesting trees no faster than they are replenished. • Protecting old-growth and vulnerable areas. Figure 10-12

  49. CASE STUDY: TROPICAL DEFORESTATION Large areas of ecologically and economically important tropical forests are being cleared and degraded at a fast rate. Figure 10-16

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