Sustaining Terrestrial Biodiversity The Ecosystem Approach G Tyler

Sustaining Terrestrial Biodiversity: The Ecosystem Approach G. Tyler Miller’s Living in the Environment 14 th Edition Chapter 11 Dr. Richard Clements Chattanooga State Technical Community College

Key Concepts Ø Human land use Ø Types and uses of US public lands Ø Forests and forest management Ø Implications of deforestation Ø Management of parks Ø Establishment and management of nature preserves Ø Importance of ecological restoration

Types of US Public Lands Ø Multiple-use lands: National Forests; National Resource Lands Ø Moderately-restricted use lands: National Wildlife Refuges Ø 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 Ø Food webs and energy flow Ø Water regulation Ø Local and regional climate Ø Numerous habitats and niches Ø Air purification

Managing and Sustaining Forests Economic Importance of Forests Ø Fuelwood (50% of global forest use) Ø Industrial timber and lumber Ø Pulp and paper Ø Medicines Ø Mineral extraction and recreation

Emergent Forest Structure Birds, invertebrates, bats Canopy Birds, reptiles, amphibians, lichens, mosses Understory Snag Shade-tolerant plants, birds, squirrels, lizards, chipmunks Floor Rotting debris, worms, insects, bacteria Fig. 23. 6, p. 592 Bole Subsoil Nematodes, microrganisms

Types of Forests Ø Old-growth (frontier) forests Ø Second-growth forests Ø Tree farms/plantation Virgin forests, 1620 Fig. 23. 13 b, p. 600 Virgin forests, 1998

Forest Management Ø Rotation cycle Ø Even-aged management Ø Industrial forestry Ø Uneven-aged management Ø Improved diversity Ø Sustainable production Ø Multiple-use

Management Strategies Weak trees removed 25 15 30 Years of growth Fig. 23. 7, p. 593 Seedlings planted 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 Ø Increased erosion and runoff Ø Habitat fragmentation Ø Pathways for exotic species Ø 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 Ø Selective cutting Ø High-grading Cut 2 Cut 1 Shelterwood Cutting Selective Cutting Seed-Tee Cutting Clear-Cutting Ø Shelterwood cutting Ø Seed-tree cutting Ø Clearcutting Ø Strip cutting Cut Uncut Cut 1 year ago 6– 10 years ago 3– 5 years ago Strip Cutting

Sustainable Forestry Ø Longer rotations Ø Selective or strip cutting Ø Minimize fragmentation Ø Improved road building techniques Ø Certified sustainable grown (See Solutions p. 598)

Pathogens Fungal Diseases Ø Chestnut blight Ø Dutch elm disease Insect Pests Ø Bark beetles Ø Gypsy moth

Fire Ø Surface fires Surface fire Ø Crown fires Crown fire

Forest Resources and Management in the United States Ø Habitat fro threatened and endangered species Ø Water purification services Ø Recreation Ø 3% of timber harvest Ø Sustainable yield and multiple use Ø Substitues for tree products

Tropical Deforestation Ø Rapid and increasing Ø Loss of biodiversity Ø Cultural extinction Ø Unsustainable agriculture and ranching Ø Clearing for cash crop plantations Ø Commercial logging Ø 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 Ø Identification of critical ecosystems Ø Reducing poverty and population growth Ø Sustainable tropical agriculture Ø Encourage protection of large tracts Ø Debt-for-nature swaps Ø Less destructive harvesting methods

The Fuelwood Crisis Ø Planting fast-growing fuelwood plants Ø Burning wood more efficiently Ø Switching to other fuels Fig. 23. 21, p. 611

Managing and Sustaining National Parks Ø Most parks are too small to maintain biodiversity Ø Invasion by exotic species Ø Popularity a major problem Ø Traffic jams and air pollution Ø Visitor impact (noise) Ø Natural regulation Ø Better pay for park staff

Establishing, Designing, and Managing Nature Reserves Ø Include some moderate disturbance Ø Sustain natural ecological processes Ø Protect most important areas Ø Buffer zones Ø Gap analysis Ø Wilderness areas See Solutions p. 620

Ecological Restoration Ø Ecological restoration Ø Restoration ecology Ø Rehabilitation Ø Replacement See Individuals Matter p. 624 Ø Creating artificial ecosystems Ø Natural restoration