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Mrs. Dow Unit Four Chapter 11. Sustaining Terrestrial Biodiversity: Managing and protecting Ecosystems. Reintroducing Wolves to Yellowstone. 8/25/2014. 2. Case Study: Reintroducing Wolves to Yellowstone. At one time the gray wolf ranged over most of North America
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Mrs. DowUnit FourChapter 11 Sustaining Terrestrial Biodiversity: Managing and protecting Ecosystems
Reintroducing Wolves to Yellowstone 8/25/2014 2
Case Study: Reintroducing Wolves to Yellowstone At one time the gray wolf ranged over most of North America 1850-1900- an ~ 2 million wolves were shot, trapped and poisoned by ranchers, hunters, and government employees Trying to make the West and Great Plains safe for livestock and big game
1973 the ESA (Endangered Species Act) was passed Only ~ 400-500 gray wolves remained in lower 48. Gray wolves an important keystone species They culled the herds of bison, elk and deer The number of bison and elk increased devastating the some of the vegetation, increased erosion and threatened the niches of other species 1995 wolves were reintroduced 2004 the number were up to 760 wolves downgraded them from endangered to threatened
Human impacts on terrestrial biodiversity 11.1 • We have degraded 50-83% of land surface • Cleared 82% of temperate forests for farming • Logged 95% of virgin forests • 98% of tall prairie grassland has disappeared • Extinction rate is 100-10,000x what is was prior to humans
Preservation of biodiversity • Needed for . . . • Goods & services • Scientific information • Recreation • Ecological services • Valuing natural beauty • Leaving capital for future generations
Conservation biology 11.2 • Conservation biology is a multidisciplinary science; its goal is to use emergency responses to slow down the rate at which we are destroying and degrading the earth's biodiversity • Identify hotspots- the most endangered and species-rich ecosystems • Rapid assessment teams (RAT) • Evaluate • Make recommendations • Take emergency actions
Bioinformatics • Applied science of managing, analyzing, communicating biological info • Tools • High-res digitized images • DNA sequencing for identifying microorganisms
11.3 Public lands National parks and preserves National forests (and Xs) National wildlife refuges
National parks and preserves National forests (and Xs) National wildlife refuges
Public lands in the U.S. 11.3 • Public lands help preserve biodiversity • U.S. has set aside more land than any other nation • More than a 1/3rd of the land in the US consist of publicly owned national forests, resource lands, parks, wildlife refuges and protected wilderness areas • 73% of that is in Alaska • National forests & resource lands (USFS) • Logging, mining, grazing, oil, gas, recreation • National Wildlife Refuges (USFWS) • Protected habitats & breeding grounds • May hunt, trap, fish, mine, log, graze, farm
National Park System (NPS) • Allows camping, hiking, sport fishing, boating, not hunting, mining or oil • National Wilderness Preservation System • Only recreational use
Arctic Circle Arctic Circle 60° EUROPE NORTH AMERICA ASIA 30°N Tropic of Cancer Atlantic Ocean AFRICA Pacific Ocean Pacific Ocean 0° 150° 120° 90° 30°W 0° 60°E 90° 150° SOUTH AMERICA Indian Ocean Tropic of Capricorn AUSTRALIA 30°S Antarctic Circle 60° ANTARCTICA Critical and endangered Threatened Stable or intact Projected Status of Biodiversity 1998–2018
Controversy over using public lands for resources • From an environmentalist approach . . . • Protect biodiversity and habitats • No subsidies for taking resources • Compensation to public for use • Extractors pay for damage • Federal gvt gives billions yearly to private interests
Developers & extractors • No federal funding for admin of land • Cut old trees and replant • Open land to drilling • Dismantling NPS – building theme parks • Support 1872 Mining Law • Repealing Endangered Species Act • Decreasing wetlands
Managing & sustaining forests 11.4 3 types 1. Old growth/frontier Not seriously disturbed by humans/natural disasters • Land at less than market value • Large amounts of diversity • 22% of world’s forest • Logging threatens 33%
2.Second-growth Develop after human activities/natural forces Secondary succession • 63% of world’s forest 3. Tree plantations/tree farms • Replant & clear-cut one species of tree in regular cycle • 5% of world’s forest
Forest management • Even-aged – tree plantations • Maintains trees about the same age & size • Replaces an old-growth forest • Uneven-aged • Variety of ages & sizes • Promotes diversity • Selectively cut various aged trees • Used for timber, wildlife, recreation
Highway Old growth Building roads into previously inaccessible forests paves the way to their fragmentation, destruction and degradation
Cleared plots for grazing Highway Cleared plots for agriculture
Logging roads • Increase erosion, sediment runoff, affect habitats, loss of biodiversity • Expose forests to invasion by nonnative pests, disease • Access to human pests (ticks) • Disqualify land for protection as wilderness
Selective cutting • Intermediate aged/mature trees cut in small groups • Reduces crowding, encourages growth of younger trees maintains a uneven-aged forest • High grading • Largest, best specimens cut • Forest floor becomes warmer, drier, subject to erosion, fire
Weak trees removed Seedlings planted Clear cut 25 15 10 30 Years of growth 5
Cut 2 Cut 1 Shelterwood Cutting
Uncut Cut Cut Cut Uncut 1 year ago 3–5 years ago 6–10 years ago Strip Cutting
Three ways to harvest trees that need full to moderate sunlight • Shelterwood cutting • Removes all mature trees in an area in two or three cuttings over a period of time • Seed-tree cutting • Removes nearly all trees but leaves a few seed-producing trees who would begin a new generation • Clear cutting • Every tree in one cutting
Trade-Offs Clear-Cutting Forests Advantages Disadvantages Higher timber yields Maximum economic return in shortest time Can reforest with genetically improved fast-growing trees Short time to establish new stand of trees Needs less skill and planning Best way to harvest tree plantations Good for tree species needing full or moderate sunlight for growth Reduces biodiversity Disrupts ecosystem processes Destroys and fragments some wildlife habitats Leaves moderate to large openings Increases soil erosion Increases sediment water pollution and flooding when done on steep slopes Eliminates most recreational value for several decades 8/25/2014 30
Effects of deforestation • Reduces biodiversity • Change regional climate • Destroys and fragments some wildlife habitats • Increases soil erosion • Emits carbon dioxide (global climate) • Original world forest decreased by 20 to 50% • Mainly in tropics
Temperate forest have increased from reforestation (secondary succession) • Some tropics have been replanted
Forest resources & management in U.S. 11.5 • 40% U.S. forests protected • U.S. mainly losing old-growth & second-growth
White pine blister rust Hemlock wooly adelgid Pine shoot beetle Sudden oak death Beech bark disease
Individuals Matter: Butterfly in a Redwood Tree • Julia “Butterfly” Hill spent 2 years of her life on a small platform near the top of a giant redwood tree in California to protest the clear-cutting of forest of these ancient trees, some of them over 1,000 years old • She lost her battle but persuaded Pacific lumber MAXXAM to save her tree called Luna and a 60- meter buffer zone around it. • Someone seriously damaged it with a chain saw cables and steel plates have been used to preserve it.
Types of fires 1. Surface fires • Burn underbrush, leaf litter, most animals survive • Germinate some plants • Can kill seedling but spare most mature trees and allow most wildlife to escape
2. Crown fires Hot & leap from tree to tree More ground litter greater destruction Destroy most vegetation, kill wildlife, increase erosion 3. Ground fires Most common in peat bogs Go underground Hard to detect & fight
Preventing forest fires • Prescribed burns • Logging leaves debris • Goats clear area • Goals • Reduce ground-level fuel • Clearing flammable vegetation around homes • Fire lanes
The Healthy Forests Initiative (HFI) was launched in August 2002 by President Bush with the intent to reduce the risks severe wildfires pose to people, communities, and the environment. • By protecting forests, woodlands, shrublands, and grasslands from unnaturally intensive and destructive fires
Healthy forest Initiative • Congress passed law in 2003 • Timber companies are allowed to cut down economically valuable medium and large trees in 71% of the country’s forest for 10 years • In return for clearing away smaller fire prone trees and underbrush • Exempts most thinning projects from environmental reviews and appeals
Controversy in national forests • Timber companies want low prices • Conservationists want less cutting • Incentives have been given to FS for selling timber • Reforesting does not include road building, overhead costs • Recreation, hunting, fishing adds more money than cutting timber
Increase efficiency of wood consumption • Construction • Excess packaging, junk mail • Paper recycling • Reuse wooden shipping containers
Use kenaf for packaging • Paper can be made without trees. • One acre of kenaf, a plant related to cotton, produces as much fibre in one year as an acre of yellow pine does in twenty.
Tropical deforestation 11.6 • Brazil • 40% remaining rainforests • Gone in 50 yrs. • 450 tree species/2 house lots • Loss of chemicals, storehouse for carbon
Rauvolfia Rauvolfia sepentina, Southeast Asia Tranquilizer, high blood pressure medication
Foxglove Digitalis purpurea, Europe Digitalis for heart failure