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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Forestry
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Outline World Forests Tropical Forests Swidden Agriculture Temperate Forests Harvest Methods Fire Management
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. WORLD LAND USES Earth’s total land area is about 29% of globe. 11% of landmass is now used for crop production. Half of present forests and grazing lands could be converted. - Immediate and destructive impacts on landscape and wildlife.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Uses of Landmass (29% of world)
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. WORLD FORESTS Forests play vital ecological roles Regulating climate, controlling water runoff, providing food and shelter for wildlife, and purifying air. Provide valuable materials. Wood, paper-pulp. Scenic, cultural, and historic value.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Forest Distribution 1/3rd of original forests and woodlands have been converted to other uses. Forests and woodlands cover 32% of earth’s land surface. Greatest concern is over protection of Old-Growth Forests. Only 22% retain old-growth characteristics.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. World Forests
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Forest Products Wood plays a part in more activities of the modern economy than any other commodity. Industrial Timber and unprocessed logs account for about half of worldwide wood consumption. - Developed countries produce less than 1/2 all industrial wood, but account for 80% of consumption.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Forest Products US, Russia, and Canada are largest producers of industrial wood and paper pulp. Japan is world’s largest wood importer. - US is both major exporter and importer. Buy wood and paper from Canada and processed wood products from Japan. Sell raw logs to Japan and other countries.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Forest Management Approximately 25% of world’s forests are actively managed for wood production. Sustainable harvest is key to regeneration. - Most countries replant far fewer trees than were harvested. Many reforestation projects involve Monoculture Cropping. Disrupts ecological processes.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. TROPICAL FORESTS Occupy 10% of landmass, and contain: More than 2/3rds of all higher plant biomass. At least 1/2 of all plant, animal, and microbial species.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Tropical Forests Shrinking 0.8% of remaining forest cleared each year. - Countries have economic and political reasons to hide extent of losses. Brazil has largest rainforests, and highest rate of deforestation.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Tropical Forests Shrinking
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Deforestation in the Amazon Basin Logging Cattle grazing
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Tropical Forest Losses
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Amazon Deforestation Remains High Even selective logging destroys canopy, causes river siltation, opens roads
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed.
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Desertification threatens forest edges
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Chipko Movement in India Women blocking mass logging, deforestation
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Swidden Agriculture Can be ecologically sound and sustainable if performed carefully and in moderation. Slash and Burn Small lot cleared, dried, and burned. - Ashes used to prepare seedbed. Fast-growing crops planted to control erosion, shade crops, and anchor soil.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Cropped intensively for 1-2 years, and then rested 10-15 years.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Logging and Land Invasions Other major source of forest destruction Bulldozed roads make it possible for people to move into the forest for farmland. - Forest clearing leads to river degradation through increased silt and sediment flow.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Debt-for-Nature Swaps Banks, governments, and lending institutions hold nearly $1 trillion in loans to developing countries. Conservation organizations buy debt obligations discount, and then offer to cancel the debt if the debtor country will agree to protect or restore an area of biological importance.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. TEMPERATE FORESTS Northern countries have a long history of liquidating forest resources. Siberia contains 1/4 of the world’s timber reserves. - Asian companies cutting 10 mil. acres/year
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Temperate Forests in the U.S.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Ancient Forests of the Pacific Northwest Redwoods can reach 3-4 m in diameter, 90 m in height and 1,000 years in age. Temperate rainforests are 2nd only to tropical rainforests in biodiversity. - Accumulate more biomass in standing vegetation per unit area. Less than 10% of virgin temperate rainforest remain (80% scheduled to be cut).
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed.
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Wilderness and Wildlife Protection Forest products industry employs about 150,000 people in the Pacific NW Adds nearly $7 billion annually to the economy. Recreation has 16x jobs.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Spotted Owl controversy 1989 environmentalists sued USFS over plans to clear-cut remaining old-growth forests, Argued spotted owls were endangered and must be protected.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Spotted Owl controversy
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Spotted Owl controversy - Timber industry claims 40,000 jobs lost. Environmentalists dispute number. Other reasons Mechanization Clear-cutting Export of logs to Japan
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Harvest Methods Clear-Cutting - Every tree in a given area is cut regardless of size. Fast and efficient, but wastes small trees, increases erosion, and eliminates wildlife habitat. Coppicing - Encourage stump-sprouts. Seed-Tree - Leave few mature trees. Shelterwood - Remove in series of cuts.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Harvest Methods Strip Cutting - Harvesting all trees in a narrow corridor. Selective Cutting - A small percentage of mature trees are taken in 10-20 year rotation. Can retain many characteristics of mature, old-growth forests.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Menominee Sustainable Forestry
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed.
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Below-Cost Salvage Sales USFS has historically regarded its primary job as providing a steady supply of cheap logs to the nation’s timber industry. Often, timber prices have not been enough to repay management costs. - Hidden subsidy to timber industry. USFS builds roads in order for timber companies to extract trees.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. FIRE
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Fires caused by poor logging practices Wisconsin, 1871: Deadliest forest fire in recorded world history kills 1,200-1,500
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Southeast Asian Rainforest Fires, 1997 Palm oil plantations
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Mexico/Central America Rainforest Fires, 1998 Cover for illegal logging
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Brazilian Amazon Rainforest Fires, 1999 Land-hungry farmers
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Fire Management Recent studies show fire plays an important role in many forested ecosystems. Eliminating fire has allowed shrubs and small trees to fill some forest floors. - As woody debris accumulates, chances of a major fire increase. Often, attempts to stop fires cause more ecological damage than the actual fires.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Fire Suppression: Wisconsin River Bluffs at Sauk City, 1870s-1990s
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Fire Management For 30 years, the NPS has followed a policy of allowing some natural fires to burn, and even setting some prescribed fires. But after 70 years of fire suppression, fuel has now built up to a point where fires can easily escape “control.” - The dilemma is how to remove excess fuel while protecting property, human life, and forest ecosystems.
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Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Yellowstone Fires, 1988
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