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Wild Species and Terrestrial Species Biodiversity

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Text of Wild Species and Terrestrial Species Biodiversity

Sustaining Wild & Terrestrial Species

Chapter 22 Sustaining Wild Species Biodiversity Estimate 12-14 million species Endangered species Threatened/vulnerable species Increase Biodiversity: physically diverse habitat moderate environmental disturbance small variations in environmental conditions (nutrient supply, precipitation, and temperature) middle stages of succession evolution Decrease Biodiversity: environmental stress large environmental disturbance extreme environmental conditions limit of an essential nutrient, habitat or other resource introduce nonnative species geographic isolation human activities red/wildlife.html Endangered vs Threatened

Human Impact What is the Human Impact on Biodiversity? increasing fragmentation, habitat loss, degradation ***greatest threat to species eliminating wetlands use/waste/destroy net primary productivity of ecosystems logging land conversion (agriculture, commercial development) destruction of coral reefs simplifying many diverse ecosystems (because of development) and preventing speciation (speciation crisis) increase speciation of opportunist species (insects/weeds) when we degrade land decrease level of higher order organisms mammals and trees pollution, use of pesticides, and climate change

Human Impacts on Biodiversity

Fig. 22-2 p. 561

Species Extinction: Local species no longer in particular area Ecological species are so few no longer play role in ecological community Biological species no longer found forever # and diversity of species balance between speciation and extinction Biodiversity = Speciation - Extinction 99.9% of all species that existed now extinct (by evolution) Extinction spasms large # lost over a few centuries to 1000 years Use models of species vs area loss of habitat (90%)causes loss of species (50%) Current rate of extinction between .1% - 1% per year (not sure) Still exponential compared to before humans existed (.0001%) extinction rates higher when biodiversity rich Ex-tropical rainforests, coral reefs

Extinct Organisms

Passenger pigeon

Great auk


Dusky seaside sparrow

Aepyornis (Madagascar)

Extinction occurs from habitat loss nonnative species hunting and poaching

Type of Nonnative Organism Crop disease Crop weeds Rats Feral cats and outdoor pet cats Crop insects Livestock diseases Forest insects and diseases Zebra mussels Common pigeon

Annual Losses and Damages $23.5 billion $23.4 billion $19 billion $17 billion $14 billion $9 billion $4.8 billion $3 billion $1.1 billion

Formosan termiteFishes Asian clam Feral pigs Starlings Fire ant

$1.1 billion $1.1 billion$1.1 billion $0.8 billion $0.8 billion $0.6 billion

Figure 22-17 (1) Page 576Purple looselife European starling African honeybee (Killer bee) Nutria Salt cedar (Tamarisk)

Marine toad

Water hyacinth

Japanese beetle


European wild boar (Feral pig)

Invasive Species

Figure 22-17 (2) Page 576Sea lamprey (attached to lake trout) Argentina fire ant Brown tree snake Eurasian muffle Common pigeon (Rock dove)

Formosan termite

Zebra mussel

Asian long-horned beetle

Asian tiger mosquito

Gypsy moth larvae

Invasive Species Continued

Streaming Facts on File Invasive Species

What does biodiversity do for us? food fuel lumber, paper medicine (for cancers alkaloids) exploration of new pharmaceuticals genetic engineering of new products pollination nutrient cycles pest control climate regulation water waste decomposition purification of air and water allow for evolution recreation ecotourism biophilia (love of life)

Solutions Bioinformatics communicating biological information Ex - via internet Ex Species 2000 lists all species for study CITES Convention on International Trade in Endangered Species (1975) now signed by 152 countries protects endangered or threatened wild species 2 US Laws: Lacey Act of 1990 prohibits transporting wild animals across states border without a permit Endangered Species Act of 1973 (ESA) amended in 1982-1988 illegal for Americans to import or trade any product made from endangered or threatened species (unless used for science) need to protect critical habitat laws hard to enforce, little fines given Wildlife Management Sanctuaries/Refuges/Zoos/Aquariums

Ch 23 Sustaining Terrestrial Biodiversity Forest Classification Tropical (47%) Subtropical (9%), Temperate (11%) Boreal (Polar) 33%

Layers of a Tree Emergent birds and bats Canopy birds and reptiles Understory shady plants, birds, squirrels Floor insects, bacteria Subsoil nematodes, microorganisms

Old growth forests (frontier) around for several hundred years uncut forests/regenerated lots of diversity Second growth forests secondary ecological succession human activity (clear cutting for timber or conversion to cropland) natural forces (fire, hurricanes, volcanoes) Tree plantations/free farms uniform trees of one species harvested by clear-cutting commercially valuable produce 10% of worlds wood

Forests provide many ecological and economic services: cycling reduce soil erosion absorb and release water purify air and water influence climate/reduce global warming store carbon provide wildlife habitats fuelwood (developing countries) provides 7% of worlds energy supply (developing 15%, 3% developed) lumber pulp to make paper mining livestock grazing recreation and jobs prescription drugs Paper Production worlds fastest growing use of wood (use pulpwood) 50% packaging, 30% writing and printing, 12% newspaper, 8% tissues/towels

Figure 23-7 Page 600Forests Ecological Services Economic Services

Support energy flow and chemical cycling Reduce soil erosion

Fuelwood Lumber Pulp to make paper

Absorb and release water

Mining Purify water Livestock grazing Purify air Recreation Influence local and regional climate Store atmospheric carbon Provide numerous wildlife habitats


Land Use: urban use (2%), cropland (11%), desert (20%), wetlands, tundra (9%),pastures/rangeland (26%), forests (32% ) Federal Public Lands vs Private Lands 35% federal, 55% private, 7% state and local, 3% native American (US) 1)multiple use lands used for all purposes mining, logging, recreation, farming, fishing, conservation National Forest System managed by US Forest Service 156 forests and 22 grasslands Bureau of Land Management (BLM) manages National Resource lands in western states and Alaska 2)moderately restricted use lands some permitted activities but regulated regulate 524 National Wildlife Refuges 3)restricted use lands 55 major parks and 324 national recreation areas (NPS-national park) only camping, hiking, fishing, boating

Land Use in the World

Fig. 23-2 p. 595

Land Use in the United States

Rangeland and pasture 29%

Fig. 23-3 p. 595

Management of US Public Lands Based on Aldo Leopolds Concept of Land Ethics) need to conserve environment humans need to be protectors of nature need to view land as a community we belong to and love and respect (not as a commodity belonging to us). Economists/developers more concerned about how useful land is for resources does it to help economic growth

Forest management

Even aged management trees same age and size industrial forestry tree plantation fast growing economically desirable 6-100 years (depends on species) Uneven aged management longer term many sizes and shapes variety of tree species biological diversity long term production quality lumber (if you want nicer furniture) selective cutting multiple use of forest (timber as well as wildlife, watershed protection, and recreation) fosters natural regeneration Tropics can be 6-10 year rotations Temperate 20-30 years rotations

Steps in Forest Management (rotation) take inventory of site develop a forest management plan build roads into site prepare sites for harvest harvest lumber regenerate and manage site until next harvest

Management StrategiesFig. 23-11 p. 601

Fig. 23-12 p. 602

Tree Harvesting: Selective cutting intermediate/mature trees in uneven-aged forest, cut individual or in small groups Shelterwood cutting removes all mature trees in 2 or three cuttings, over 10 years Seed-tree cutting harvests all in 1 cutting, leaves a few seed-producing trees to regenerate Clear-cutting removes all trees from an area in a singe cutting Strip cutting clear cutting of forest in narrow strips over several decades with minimal damage

Selective Cutting

Cut 2 Cut 1 Shelterwood Cutting


Seed-Tree Cutting


35 years ago 1 year ago 610 years ago





Strip Cutting

Impacts of Deforestation: reduces biodiversity reduces uptake of greenhouse gases CO2 adds CO2 if trees burned or allowed to decay (contributed 30% of buildup of CO2) affects precipitation decline of rainfall increases soil erosion accelerates floods by removing tree cover

Degradation of Tropical Forests

Fig. 23-22 p. 615

Outside Influences on Forests: 1)Disease parasitic fungi Chestnut blight Dutch Elm Disease White Pine Blister Rust 2)Insects Ex Beetles, moth, larvae, worms 3)Fires Surface fire removes bottom lowlying vegetation and small trees good when occasional secondary succession Crown fire more serious larger trees/larger scale mass destruction Smokey Bear tries to prevent 4)Air Pollution and Climate Change (too warm/no rain/more fires)

Chestnut blight has eliminated Chestnut trees as a commercial tree. (no cure)

Surface Fire

Crown Fire


Surface fires

Crown fires

Fig. 23-17 p. 607

Solutions sustainable grow more timber on long rotations strip cutting/selective cutting instead of clear cutting minimize fragmentation minimize erosion reduce road building into uncut forest leaving standing dead trees (snags) and fallen timber (boles) to maintain wildlife habitats/recycled as nutrients switch to nonrenewable resources (ironic to say) Ex use steel/aluminum framing, carpeting genetically improved trees on tree plantations (that use less space) debt for nature swap protect nature and we will give you foreign aid or debt relief use tree-free fibers Ex Kenaf in US (rapidly growing woody annual plant, expensive, 3 times more expensive) Florida Stewardship Council

National Parks

1100 National Parks in World US National Park System established in 1912 55 National Parks (most in west) Parks/ Reserves should be placed in worlds most biodiverse countries (rainforests) and at hot spots - areas rich in plants and animals Nature Parks/Preserves (to protect biodiversity) 1)Circular reserve better than rectangle? YES - less edges 2)Single large preserve vs several small reserves? Large Preserve - Better to maintain large species/more species Several Small Reserves - wider variety of habitats/more biodiversity/ cannot be devastated) 3)Homogeneous or heterogeneous reserve? better to have heterogeneous because have a variety of habitat patches -patch dynamics with different sizes, shapes, and successional stages 4)Should small reserves be connected or isolated? should be connected by habitat corridors helps support more species allows for migration of animals if conditions unsuitable (like global warming) 5)Want Buffer zones (biosphere reserve) inner core surrounded by buffer zones

Biosphere Reserve

Human settlements

Tourism and education center Research station

Core area Buffer zone 1 Buffer zone 2

Want to always preserve wilderness US Wilderness Act of 1964 Wilderness - areas of undeveloped land man visits but does not remain Should be at least 150 square miles 2002 Edward Wilson big leader in biodiversity, book Future of Life