Sustaining Terrestrial Biodiversity: The Ecosystem Approach G. Tyler Miller’s Living in the Environment 12th Edition Chapter 23 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
Land Use in the World Urban 2% Cropland 11% Tundra and wetlands 9% Desert 20% Cropland 11% Rangeland and pasture 26% Forest 32% Urban 2% Fig. 23.2, p. 586
Land Use in the United States Rangeland and pasture 29% U.S. Land Use Forest 30% Parks, wildlife refuge, wilderness 9% Desert, tundra, wetlands 13% Urban 2% Cropland 17% U.S. Land Ownership Federal 35% Native American 3% State and local 7% Private 55% Fig. 23.3, p. 586
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
National parks and preserves National wildlife refuges US Public Lands National parks and preserves National forests National wildlife refuges
Managing US Public Land Biodiversity and ecological function No subsidies or tax breaks for use Public should get fair compensation Users held responsible for actions Takings and property rights
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
Forest Structure Emergent Canopy Understory Floor Subsoil Birds, invertebrates, bats reptiles, amphibians, lichens, mosses Shade-tolerant plants, birds, squirrels, lizards, chipmunks Rotting debris, worms, insects, bacteria Nematodes, microrganisms Bole Snag Fig. 23.6, p. 592
Types of Forests Old-growth (frontier) forests Second-growth forests Tree farms/plantation Virgin forests, 1620 Virgin forests, 1998 Fig. 23.13b, p. 600
Forest Management Rotation cycle Even-aged management Industrial forestry Uneven-aged management Improved diversity Sustainable production Multiple-use
Management Strategies Years of growth 30 25 15 10 5 Clear cut Weak trees removed Seedlings planted Time Short rotation Wood volume or wood biomass B C A Long rotations Old-growth harvest (such as hardwoods for furniture) Fig. 23.7, p. 593 Fig. 23.9, p. 594