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Sustaining Terrestrial Biodiversity: The Ecosystem Approach G. Tyler Miller’s Living in the Environment 14th Edition Chapter 11 Dr. Richard Clements Chattanooga State Technical Community College Key Concepts Human land use Types and uses of US public lands Forests and forest management Implications of deforestation Management of parks Establishment and management of nature preserves Importance of ecological restoration Types of US Public Lands Multiple-use lands: National Forests; National Resource Lands Moderately-restricted use lands: National Wildlife Refuges Restricted-use lands: National Park System; National Wilderness Preservation System US Public Lands National parks and preserves National forests National wildlife refuges Managing and Sustaining Forests Ecological Importance of Forests Food webs and energy flow Water regulation Local and regional climate Numerous habitats and niches Air purification Managing and Sustaining Forests Economic Importance of Forests Fuelwood (50% of global forest use) Industrial timber and lumber Pulp and paper Medicines Mineral extraction and recreation Emergent Forest Structure Birds, invertebrates, bats Canopy Birds, reptiles, amphibians, lichens, mosses Understory Shade-tolerant plants, birds, squirrels, lizards, chipmunks Snag Floor Rotting debris, worms, insects, bacteria Subsoil Fig. 23.6, p. 592 Bole Nematodes, microrganisms Types of Forests Old-growth (frontier) forests Second-growth forests Tree farms/plantation Virgin forests, 1620 Fig. 23.13b, p. 600 Virgin forests, 1998 Forest Management Rotation cycle Even-aged management Industrial forestry Uneven-aged management Improved diversity Sustainable production Multiple-use Management Strategies Weak trees removed 25 Seedlings planted 15 30 Years of growth Fig. 23.7, p. 593 10 5 Wood volume or wood biomass Clear cut B Long rotations C Old-growth harvest (such as hardwoods for furniture) A Short rotation Time Fig. 23.9, p. 594 Logging Roads Increased erosion and runoff Habitat fragmentation Pathways for exotic species Accessibility to humans Highway Cleared plots for grazing Cleared plots for agriculture Virgin forest Highway Fig. 23.10, p. 595 Harvesting Trees Fig. 23.11, p. 596 Selective cutting High-grading Cut 2 Cut 1 Shelterwood Cutting Selective Cutting Seed-Tee Cutting Clear-Cutting Shelterwood cutting Seed-tree cutting Clearcutting Strip cutting Cut Uncut Uncut Cut Cut 1 year ago 6–10 years ago 3–5 years ago Strip Cutting Sustainable Forestry Longer rotations Selective or strip cutting Minimize fragmentation Improved road building techniques Certified sustainable grown (See Solutions p. 598) Pathogens Fungal Diseases Chestnut blight Dutch elm disease Insect Pests Bark beetles Gypsy moth Fire Surface fires Surface fire Crown fires Crown fire Forest Resources and Management in the United States Habitat fro threatened and endangered species Water purification services Recreation 3% of timber harvest Sustainable yield and multiple use Substitues for tree products Tropical Deforestation Rapid and increasing Loss of biodiversity Cultural extinction Unsustainable agriculture and ranching Clearing for cash crop plantations Commercial logging Fuelwood Degradation of Tropical Forests Bromeliad Primary Causes: Rapid population growth Poverty Exploitive government policies Exports to developed counties Failure to include ecological services in evaluating forest resources Toucan Scarlet macaw Golden lion marmoset Orchid Secondary Causes: Roads Logging Unsustainable peasant farming Cash crops Blue morpho butterfly Cattle ranching Tree plantations Flooding from dams Mining Oil drilling Fig. 23.18, p. 608 Reducing Tropical Deforestation Identification of critical ecosystems Reducing poverty and population growth Sustainable tropical agriculture Encourage protection of large tracts Debt-for-nature swaps Less destructive harvesting methods The Fuelwood Crisis Planting fast-growing fuelwood plants Burning wood more efficiently Switching to other fuels Fig. 23.21, p. 611 Managing and Sustaining National Parks Most parks are too small to maintain biodiversity Invasion by exotic species Popularity a major problem Traffic jams and air pollution Visitor impact (noise) Natural regulation Better pay for park staff Establishing, Designing, and Managing Nature Reserves Include some moderate disturbance Sustain natural ecological processes Protect most important areas Buffer zones Gap analysis Wilderness areas See Solutions p. 620 Ecological Restoration Ecological restoration Restoration ecology Rehabilitation Replacement See Individuals Matter p. 624 Creating artificial ecosystems Natural restoration