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Unit 6: Sustaining Biodiversity. January 8, 2012 AP Environmental Science Mr. Plowman. LT 6A : Discuss the role human activities play in extinction. Biological extinction: a species has disappeared from the earth. Background extinction is an historic, continuous, low level of extinction.
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Unit 6:Sustaining Biodiversity January 8, 2012 AP Environmental Science Mr. Plowman
LT 6A: Discuss the role human activities play in extinction. • Biological extinction: a species has disappeared from the earth. • Background extinction is an historic, continuous, low level of extinction. • Extinction rate is the percentage or number of species that go extinct each year. • Mass extinction is the loss of many species in a short period of time.
LT 6A: Discuss the role human activities play in extinction. • Human activities increase the pace of extinction. • Current rate is 100—1,000 times the background rate (0.01–.1% per year). • Predictions hold that this will rise to 10,000 times that background rate during this century. • Under this scenario ¼ to ½ of all species will be extinct by the end of the century.
LT 6A: Discuss the role human activities play in extinction. • Why should we care about the rising rate of species extinction? • four reasons we should prevent our activities from causing extinctions. • Species are a vital part of earth’s life support system. • Species support our economy (materials, medicines, ecotourism). • It will take millions of years for natural speciation to rebuild biodiversity. • Species have a right to exist, regardless of their usefulness.
LT 6A: Discuss the role human activities play in extinction. • There are several causes of depletion and premature extinction of wild plants and animals. The acronym HIPPCO describes these causes. • Habitat destruction, degradation, and fragmentation* • Invasive species • Population growth and increasing use of resources • Pollution • Climate change • Overexploitation * Habitat destruction, degradation and fragmentation is greatest threat
LT 6B: Describe the significance of the U.S. Endangered Species Act • Initiated in 1973 and amended in 1982, 1985, and 1988 • Designed to identify and protect endangered species in the US and abroad • National Marine Fisheries Service (NMFS) and the U.S. Fish and Wildlife Service (USFWS) are the agencies responsible for identifying and listing endangered and threatened species • List MUST be based on biological factors alone, without consideration of economic or political factors
LT 6B: Describe the significance of the U.S. Endangered Species Act • Once a species is identified as endangered/threatened the act does the following: • Forbids federal agencies (except department of defense) to carry out, fund, or authorize projects that would jeopardize species or their habitats • Makes it illegal for Americans to: • Sell or buy any product made from such species • Hunt, kill, collect or injure such species • Protects an additional 573 species from other countries
LT 6B: Describe the significance of the U.S. Endangered Species Act • Between 1973 and 2010 the number of US species on the list increased from 92 to more than 1370 • In 2009 90% of the species on the listed were covered by active recovery plans • In 1982 amended to give private landowners incentives to help save endangered/threatened species
LT 6C: Identify and describe the major threats to forest ecosystems and discuss possible solutions for sustainability • Two types of natural forests • Old-growth: not seriously disturbed by humans • Second-growth: resulting from secondary ecological succession; affected by human activities • Forests provided important economic and ecological services • Support energy flow and chemical cycling • Reduce soil erosion • Purify water and air
LT 6C: Identify and describe the major threats to forest ecosystems and discuss possible solutions for sustainability • Major threats to forest ecosystems: • Unsustainable logging • Fire • Insects • Climate change • Deforestation
LT 6D: Identify and describe the major threats to grasslands, parks and nature reserves.. • Major threat to grassland is overgrazing • Can be more sustainable by controlling the number of animals • Major threat to US Parks is popularity • Between 1960 and 2008 the number of visitors more than tripled • Major threat to nature reserves is economic development • Developers and resource extractors oppose protecting undisturbed ecosystems
LT 6E: Illustrate how we can help sustain terrestrial biodiversity using the ecosystem approach • Focus on protecting and sustaining ecosystems and on the biodiversity contained within them by employing the following four-point plan: • Map the world’s terrestrial ecosystems and create an inventory of the species and natural services in them • Locate and protect most endangered ecosystems and species • Seek to restore as many degraded ecosystems as possible • Make development biodiversity-friendly by providing incentives
LT 6E: Illustrate how we can help sustain terrestrial biodiversity using the ecosystem approach Ecological services Economic services Fuelwood Lumber Pulp to make paper Mining Livestock grazing Recreation Jobs • Support energy flow and chemical cycling • Reduce soil erosion • Purify water and air • Influence local and regional climate • Store atmospheric carbon • Provide numerous wildlife habitat
LT 6F: Identify and describe the major threats to aquatic biodiversity…. • Three general patterns related to marine biodiversity • Greatest marine biodiversity occurs in the coral reefs, estuaries and on the deep-ocean floor • Biodiversity is higher near the coasts than in the open sea because of the greater variety or producers • Biodiversity is generally higher in the bottom region of the ocean than in the surface because of the greater variety of habitats and food sources on the ocean bottom
LT 6F: Identify and describe the major threats to aquatic biodiversity…. • Major threats to aquatic biodiversity • HIPPCO • Habitat loss and degradation* • Introduction of invasive species • Population growth • Pollution • Climate change • Overfishing and extinction * Greatest threat is habitat loss and degradation
LT 6F: Identify and describe the major threats to aquatic biodiversity…. • Protecting marine biodiversity is difficult because: • Human ecological footprint and fishprint are expanding rapidly so it is difficult to monitor • Much of the damage is not visible to most people • Incorrectly viewed as inexhaustible resources that can absorb an infinite amount of waste and pollution • Most of the world’s ocean area lie outside the legal jurisdiction of any country
LT 6G: Identify and describe major threats to … fishing and wetlands… • Steps to protect and sustain marine fisheries: • Estimate and monitor fish populations • Regulate fish harvests • Stop offering subsidies than can encourage overfishing • Consumer choices to demand sustainable seafood: know how and where the fish was caught
LT 6G: Identify and describe major threats to … fishing and wetlands… • Wetlands • Are important reservoirs of aquatic biodiversity • Provide vital ecological and economic services • Have been drained, filled in or covered over to: • Create rice fields or other cropland • Accommodate expanding cities and suburbs • Build roads • Have been destroyed in order to extract minerals, oil and natural gas and to eliminate breeding grounds for insects • Will most likely become submerged because of rise in sea levels
LT 6H: Discuss priorities for sustaining aquatic biodiversity • Ecosystem approach: • Complete mapping of the world’s aquatic biodiversity • Identify and preserve world’s aquatic biodiversity hotspots • Create large and fully protected marine reserves • Protect and restore the world’s lake and river systems • Initiate ecological restoration projects worldwide in systems such as coral reefs and inland and coastal wetlands • Find ways to raise the incomes of people who live in or near protected lands and waters so that they can become partners in protecting and sustaining aquatic ecosystems