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Chapter 12 Topics:  Ecological and economic contributions of forests  History and scale of deforestation  Forest management and harvest methods  U.S.

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Presentation on theme: "Chapter 12 Topics:  Ecological and economic contributions of forests  History and scale of deforestation  Forest management and harvest methods  U.S."— Presentation transcript:

1 Chapter 12 Topics:  Ecological and economic contributions of forests  History and scale of deforestation  Forest management and harvest methods  U.S. forest policy, origin and challenges  Types and design of protected areas

2 Many kinds of forests exist  Forest = any ecosystem with a high density of trees  Plant communities differ due to soil and climate  Forest types are defined by predominant tree species  Boreal forest = in Canada, Scandinavia, and Russia  Tropical rainforest = South and Central America, Africa, Indonesia, and southeast Asia  Temperate deciduous forests, temperate rainforests, and tropical dry forests also exist  Woodlands = ecosystems with lower density of trees

3 Distribution of forests  Forests cover 31% of Earth’s surface

4 Forests in the U.S.  The Eastern U.S. has 10 forest types  Spruce-fir,  Oak-hickory  Longleaf-slash pine  The Western U.S. holds 13 forest types  Douglas fir  Ponderosa pine  Pinyon-juniper woodlands

5 Forests are ecologically complex  Forests can have very rich biodiversity  Structurally complex, with many niches; provide food and shelter for multitudes of species  Plant diversity leads to greater overall diversity  Succession changes species composition  Old-growth forest diversity exceeds that of young forests due to higher structural diversity, habitats, and resources

6 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  Cycle nutrients via root uptake and leaf litter decay

7 Carbon storage limits climate change  Carbon storage by forests is of great international interest as nations debate climate change  Trees absorb carbon dioxide and store carbon  The world’s forests store 280 billion metric tons of C  Cutting forests worsens climate change  Dead plants decompose and release carbon dioxide  Fewer trees soak up less carbon dioxide  Preserving forests keeps carbon out of the atmosphere

8 Forests provide valuable resources  Primary resource is timber (lumber, fuel, paper)  Boreal forests: Canada, Russia  Rainforests: Brazil, Indonesia  Conifer forests/ plantations: U.S.  Other benefits: medicines, food  Worldwide, forests are designated for many uses

9 Demand leads to deforestation  Deforestation = the clearing and loss of forests  Changes landscapes and ecosystems  Reduces biodiversity and disrupts ecosystem service  Worsens climate change  Deforestation rate is slowing  Still lose 12.8 million acres/year

10 Deforestation fed U.S. growth  Eastern deciduous forests harvested first, then south to the Ozarks, then west to the Rockies  Primary forest = natural forest uncut by people  Secondary forest = contains second-growth trees (smaller trees, different species and forest structure)

11 Deforestation – current trends  Uncut tropical forests remain in many developing countries (Brazil, Indonesia, and West Africa)  Technology allows for even faster exploitation  Developing countries are desperate for economic development and have few logging restrictions  Concession = corporations pay the government for the right to extract resources  Wood is exported to North America and Europe  Temporary jobs are soon lost, along with the resources

12 Palm oil plantations  Palm oil is used in snack foods, soaps, cosmetics, biofuel  Pesticides and fertilizers from palm oil agriculture disrupt ecosystems  Clearing encourages further development and illegal logging  Borneo has lost most of its forest cover

13 Reducing deforestation  Conservation concessions = organizations team up to reduce deforestation and illegal logging  Carbon offsets = curb deforestation & climate change (forest loss = 12–25% greenhouse gas emissions)  Reducing Emissions from Deforestation and Forest Degradation (REDD)  REDD emerged from 2009 Copenhagen climate conference  Wealthy nations would pay poor nations to conserve forests  Guyana could earn $580 million/year by cutting forests  Norway will pay $270 million by 2015 for conservation

14 Forest management  Forestry (silviculture) = forest management  Foresters = professional managers who balance demand for forest products (short-term benefits) vs. the importance of forests as ecosystems (long term)  Resource management = strategies to manage and regulate potentially renewable resources  Sustainable management does not deplete resources  Managers are influenced by social, political, and economic factors

15 Maximum sustainable yield  Maximum sustainable yield = aims to achieve the maximum amount of resource extraction without depleting the resource from one harvest to the next  Populations grow fastest when the population size is at half its carrying capacity  Harvesting to keep the population at this size results in maximum harvest while sustaining the population

16 Problems with this approach  Managed populations are smaller than natural ones  Reducing populations affects other species, changing the entire ecosystem  Trees are cut before they grow to maximum size, changing forest ecology, eliminating habitats

17 Ecosystem-based management  Ecosystem-based management = managing resource harvesting to minimize impacts on ecosystems and ecological processes  Sustainably certified forestry plans protect areas  Restore ecologically important habitats  Consider patterns at the landscape level  Preserve the forest’s functional integrity  It is challenging to implement this type of management  Ecosystems are complex  Our understanding of how they operate is limited

18 Adaptive management  Adaptive management = testing different approaches and aiming to improve methods through time  Monitoring results and adjusting methods as needed  Time-consuming and complicated, but effective  The 1994 Northwest Forest Plan resolved disputes between loggers and preservationists over the last U.S. old-growth temperate rainforests  The plan let science guide management  Allowed limited logging but protected species & ecosystems

19 The origin of U.S. forest policy  Depletion of eastern U.S. forests caused alarm  National forest system = public lands set aside to grow trees, produce timber, protect watersheds, and ensure future timber supplies (8% of U.S. land area)  The U.S. Forest Service was established in 1905  Manages forests for the greatest good of the greatest number in the long run  Management includes logging and replanting trees

20 Current trends – private land  Most U.S. logging occurs on private land owned by timber companies using maximum sustained yield  The timber industry focuses on timber plantations (fast- growing, single-species monocultures)  Even-aged stands= all trees the same age, cut at same time, replanted  Uneven-aged stands mixed ages/species  Tree plantations are crops, not ecologically functioning forests

21 Current trends – public land  Logging also occurs on public land (subsidized)  The Forest Service plans/manages sales, builds roads  Private companies log and sell the timber for profit  Management on public lands reflects social and political factors that change over time  Public concern, changing management philosophies, and economics have caused harvests to decrease  But the secondary forests that replace primary forests are less ecologically valuable

22 Harvesting methods – clear-cutting  Clear-cutting = all trees in the area are cut  Greatest ecological impact  Most cost-efficient  May mimic some natural disturbance (e.g., storms)  Leads to soil erosion  Public outrage caused companies to use other harvesting methods

23 Harvesting methods - alternative  Seed-tree approach = a few seed-producing trees are left standing to reseed the logged area  Shelterwood approach = some trees are left to provide shelter for the seedlings as they grow  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 and affect species  Change forest structure and composition  Increased runoff, flooding, erosion, siltation, landslides

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25 Managing public forests  Increased public awareness caused people to urge that forests be managed for recreation, wildlife, and ecosystem integrity, instead of only for logging  Multiple use policy = national forests are supposed to be managed for recreation, habitat, minerals, and other uses, but timber production is still the primary use

26 National Forest Management Act  In 1976, new law required every national forest formulate plans for 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

27 Implementing the NFMA  U.S. Forest Service developed new programs:  Ecosystem-based management of wildlife, non-game animals, endangered species  Ecological restoration projects  Timber cuts that mimic natural events  Politics influence forestry management  Bush administration loosened environmental protections and restricted public oversight  The roadless rule, which protected 31% of national forests from logging, repealed in 2004  Court rulings reinstated the roadless rule in 2009

28 Fire policy  Since 1095, Forest Service has suppressed all fires  Growing recognition that this may need to change  Many ecosystems depend on fires  Excess vegetation produces kindling for future fires  The wildland-urban interface, housing developments near forests, are vulnerable  Catastrophic fires have become more numerous

29 Fire as a management tool  Prescribed (controlled) burns = burning areas of forests under carefully controlled conditions  Clear away fuel loads, nourish soil, encourage growth  Time-intensive; impeded by public misunderstanding  Healthy Forests Restoration Act (2003) = promotes removal of small trees, underbrush, and dead trees

30 Salvage logging  Removal of dead trees following a natural disturbance  It seems logical, but is really destructive  Snags (standing dead trees) provide nesting and roosting cavities for countless animals  Removing timber from recently burned areas increases erosion and soil damage  Impedes forest regeneration and promotes future fires

31 Climate change is altering forests  The U.S. is getting warmer and drier  Large fires are linked to weather conditions  Pest outbreaks are linked to weather conditions  Woodlands, shrub lands, or grasslands may replace forests

32 Sustainable forestry initiatives  Sustainable forest certification = sustainably produced products certified by organizations  Forest Stewardship Council (FSC) has strictest standards  Companies such as Home Depot sell sustainable wood, encouraging better logging practices  Consumers look for logos to buy sustainably produced timber

33 Protected lands  National parks = public lands protected from resource extraction and development  Open to nature appreciation and recreation  Yellowstone National Park was established in 1872  The Antiquities Act (1906) lets the president declare public lands as national monuments

34 The National Park Service (NPS)  Created in 1916, administers parks and monuments  392 sites totaling 34 million ha (84 million acres)  Includes national historic sites, national recreation areas, national wild and scenic rivers  285 million visitors in 2009  These parks are “the best idea we ever had”  There are also 3,700 state parks across the U.S.

35 National Wildlife Refuges  Begun in 1903 by President Theodore Roosevelt  39 million ha (96 million acres) in 550 sites  The Pacific Remote Islands Marine National Monument added 22 million ha (55 million acres)  U.S. Fish and Wildlife Service (USFWS)  Administers wildlife refuges  Allows for hunting, fishing, wildlife observation, photography, education  Managed for waterfowl and non-game species  Restores marshes and grasslands

36 Wilderness areas  Wilderness areas = are off-limits to development  Established within federal lands and overseen by the agencies that administer those lands  756 areas, 44 million ha (109 million acres)  For minimal impact activities (hiking, nature study)  Grazing/mining were allowed as political compromise

37 Opposition to protected land  Opposition to restricted use of public lands is more common in the western U.S. where much of the land is owned by the Federal government  “The wise-use movement” = individuals and industries opposed to environmental protection want Federal lands transferred to state or private hands  During Bush Administration, Federal agencies shifted policies away from preservation and conservation toward recreation and resource extraction

38 Other land protection  Each U.S. state has agencies that manage resources on public lands as do many counties and municipalities  Land trusts = local or regional organizations that purchase land to protect it  The Nature Conservancy is the world’s largest land trust  Trusts own 690,000 ha (1.7 million acres) and protect an additional 4.1 million ha (10.2 million acres)  Jackson Hole, Wyoming is protected by a land trust

39 International trends  Many nations have established national parks  Protect areas cover 12% of the world’s land area  Parks do not always receive necessary funding  Biosphere reserves = land with exceptional biodiversity  Couple preservation with sustainable development  World Heritage sites = 890 sites in 148 countries listed for their natural or cultural value

40 Designing protected lands  Studying the effects of habitat fragmentation informs the design of protected lands  Logging, agriculture, and residential development fragment habitat  Fragmentation is the main reason populations of North American songbirds are declining

41 Effects of habitat fragmentation  Edge effects = conditions along edges are different than conditions in the interior  Interior bird species can’t reproduce when forced near an edge  Nest are vulnerable to parasites and predators from the other habitat

42 Fragments are like islands  Island biogeography theory = explains how species come to be distributed among islands  The number of island species results from a balance between species added versus species lost  Predicted by the island’s distance from the mainland and its size  Distance effect: the farther an island is from the continent, the fewer species find and colonize it

43 Island biogeography  Area effect = large islands have more species  They have more habitats, environments, and variety  They have higher immigration rates – they are fatter targets  They have lower extinction rates – more space allows for larger populations

44 Parks as islands  The size and placement of protected areas are key to protecting biodiversity  Protected parks are small “islands” surrounded by development (farms, roads, cities)  The SLOSS dilemma = which is better to protect species: a single large or several small reserves?

45 Protected areas & climate change  Global climate change threatens to undo our efforts to design, establish, and guard protected areas  Species try to shift northward with warmer temperatures but species can’t move in a fragmented habitat  High-elevation species are most at risk because there is no place for them to go  Corridors to allow movement become important

46 Take-aways  We are losing ecologically and environmentally valuable forests  Resource management policies first emphasized extraction; then shifted to sustained yield and multiple use  Sustainable forest certification provides economic incentives for responsible conservation of forests  Public support for land preservation resulted in parks and protected areas in the U.S. and abroad


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