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Unformatted text preview: Managing Forest Land Managing Forest Land 32% of earth’s surface is forest, 30% in USA Old growth forests most ecologically diverse Secondary Forests follow disturbance Tree plantationsmanaged with uniform species of same age Management Management
How often trees harvested Depends on use Short Rotation Cycles pulp for paper, fuelwood 610 years in tropical forests, 2030 years temperate forests Longer Rotation cycles required for higher quality wood Management Management Even Aged Managementsame age and size plantations Uneven Aged Management Maintain variety of sizes, selective cutting foster biodiversity, long term sustainability, multiple uses Harvesting Techniques Harvesting Techniques Build a Logging Road opens access disqualifies land for protection as wilderness Clear cutting remove all trees Selective cuttingcut older trees singly Shelterwood cutting remove older trees in 23 cuttings over 10 years Seedtree cutting leave a few trees to reseed Clear cutting Clear cut forest in Oregon Shelterwood cut forest Seed tree cut forest Seed tree cut forest Tropical Forests Tropical Forests 6% of world land area, 47% of forest cover 30% of species in Brazil tropical rain forest Half area has been cleared since 1950 Population growth, poverty, govt. policies encourage deforestation Tropical Forests Tropical Forests Commercial Logging clear cutting Unsustainable farming Cash crops Mining Fuelwood15% of fuel supply Amazon Rainforest cleared For Agriculture Satellite Image of forest destruction in Bolivia for soybean cultivation Solutions Solutions Alternative fuels Sustainable Agroforestry/Multilayered cultivation Strip cutting of forests with long regeneration cycles Promote utilitarian uses of the forests Long Rotations Selective cutting Strip cutting Minimize fragmentation Reduce road building Leave dead trees/fallen timber for habitats US ForestsMaintaining US ForestsMaintaining Diversity Designing Nature Preserves Designing Nature Preserves Ecosystems are rarely stable Moderate disturbance leads to greatest diversity Prevention Strategy Reduce future loss by preserving species rich areas internationally or Emergency action Identify “hot spots” diverse areas in danger of habitat loss Shape Circular is ideal interior is buffered; depends on available land Size one large vs several small Heterogeneity allows for movement and managing disturbance Corridors between reserves Buffer zones allow some resource extraction Management Goals Management Goals Maintain native ecosystem Sustain native species while controlling invasive species Sustain ecological processes succession, natural cycles, etc. Maintain evolutionary potential of species and ecosystem Allow sustainable human use of resources in ways that do not harm longterm sustainability Adaptive Ecological Management Integrate ecological, social and economic principles to maintain and restore, while supporting community and local economies Ecological Restoration Ecological Restoration Restoration or replacement? Identifying causes of damage Pollution, overgrazing, invasive species Mimic nature wherever possible Recreate niches that have been lost Rely on pioneer species, succession Remove nonnative species ...
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- Fall '08