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Chapter 38 Conservation Biology We are now living through a biodiversity crisis A rapid decrease in Earth’s great variety of organisms 6th mass extinction event in Earth’s history PowerPoint Lectures for Biology: Concepts and Connections, Fifth Edition – Campbell, Reece, Taylor, and Simon Lectures by Chris Romero Modified by K. McCoy Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings THE BIODIVERSITY CRISIS: AN OVERVIEW 38.1 Human activities threaten Earth’s biodiversity • Biodiversity includes – Genetic diversity, within and between populations --raw material for adaptation – Species diversity – Ecosystem diversity Figure 38.1B Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings • Human activities – Threaten diversity at all levels Figure 38.1A Known extinct during historical times or threatened with extinction 12% if birds 24% mammals 20% of all freshwater fish 200 species of plants in US extinct 730 endangered Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Biodiversity is valuable for its own sake Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Biodiversity is valuable for its own sake (movie) Some people believe that all living organisms have an innate right to life. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Biodiversity is valuable for its own sake and… 38.2 Biodiversity is vital to human welfare – Also provides food, clothing, shelter, oxygen, medicines, and ecosystem services – 25% of all prescriptions are plant based Rosy periwinkle is native to Madagascar 8000 species of flowering plants many not studied yet Madagascar has lost 80% of its forests and 50% of its native species! Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Figure 38.2 Rosy periwinkle treats cancer Ecosystem diversity •Network of interactions among populations of different species. •Means that extinction of one species can negatively impact the ecosystem and connected ecosystems…(aquatic to terrestrial) •Each ecosystem has a global function… if altered can affect biosphere • “protective pastures” of phytoplankton in ocean uses CO2 for photosynthesis (producers) and for building shells… – Feeding us and protecting us from global warming… Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Ecosystem services •Ecosystems have economic value • Wetland reduce severity of floods • Natural predators reduce crop pests • Pollination • Plants purify air • Decomposition of waste • Nutrient cycling •Value of services 1997 = 33 trillion US $ •Global gross national product 1997 = 18 trillion GNP~ total market value goods and services produced plus the income accruing as a result of investments. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings So ecosystems are valuable and necessary for maintaining our current comfortable way of life. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Humans are a part of the environment and not apart from it. Your actions affect other organisms. The things we eat, wear, drive, and purchase have a direct impact on organisms, populations, and communities around the globe. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Figure 38.3A 38.3 Habitat destruction, introduced species, and overexploitation are the major threats to biodiversity • Introduced species – Can disrupt communities by competing with or preying on native species Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings • Figure 38.4 Habitat destruction Chemical pesticides May be concentrated by biological magnification – Phytoplankton absorb chemicals – Zooplankton eat a lot of phytoplnkton Concentration of PCBs • Herring gull eggs 124 ppm Lake trou 4.83 ppm Smelt 1.04 ppm – Fish eat a lot of zooplankton – Larger fish eat a lot of small fish – Birds and humans eat a lot of large fish Zooplankton 0.123 ppm Phytoplankton 0.025 ppm Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 38.4 Pollution compounds our impact on other species • Effects of pollution include – Acid rain, ozone depletion, eutrophication, and dead zones (http://www.smm.org/deadzone/what/top.html and http://www.smm.org/deadzone/causes/top.html) A Dead Zone is a large region of the ocean that is very low in oxygen, and therefore can't support life. Dead Zones occur along many of the world's coastlines and are caused by fertilizer and sewage and other nutrients. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings • Overexploitation of wildlife by harvesting – Has threatened various animal and plant species Figure 38.3B Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 38.5 Rapid global warming is altering entire biosphere • Burning of fossil fuels – Is increasing the amount of CO2 and other greenhouse gases in the air 1.05 0.90 CO2 concentration (ppm) 380 0.75 370 Temperature 0.60 360 0.45 350 0.30 340 0.15 330 CO2 0 320 –0.15 310 Figure 38.5A –0.30 300 –0.45 1960 1965 1970 1975 Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 1980 1985 Year 1990 1995 2000 2005 Temperature variation (°C) 390 Rapid global warming is altering entire biosphere • The increase of these gases in the atmosphere – leading to global warming Global warming: CO2 lets sunlight through but retains the heat radiated from Earth. Human activities and natural processes add CO2 to the atmosphere, increasing the effect. Photosynthesis removes CO2 from the atmosphere, decreasing the effect. CO2 CO2 in the atmosphere CO2 CO2 Destroying rain forest and causing dead zones in the ocean…increase global warming Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Figure 38.5B • Global warming may – Change climate patterns, melt polar ice caps, flood coastal regions – Increase the rate of species loss – Affect coastal communities of humans Figure 38.5C Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings So we are destroying the Earth… Can we do anything about it? YEP, MANY PEOPLE ARE. Conservation biology: Is a goal-driven science that seeks to counter the biodiversity crisis. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings CONSERVATION OF POPULATIONS AND SPECIES Major Threat: Habitat degradation – Often fragments populations, causing their numbers to decline Figure 38.6A, B Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings CONSERVATION OF POPULATIONS AND SPECIES 38.6 Two ways to study endangered populations • The small-population approach – Identifies the minimum viable population size and focuses on preserving genetic variation • The declining-population approach – Diagnoses and treats the causes of a population’s decline Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings MANAGING AND RESTORING ECOSYSTEMS Sustaining ecosystems and landscapes is a conservation priority 38.8 • Conservation efforts – Are increasingly aimed at sustaining ecosystems and landscapes (habitats) Figure 38.8A, B Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Figure 38.8C 38.7 Identifying critical habitat factors can guide conservation efforts • Preserving and managing critical habitat – May help endangered species recover Figure 38.7A–C Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings • Migratory species, both terrestrial and aquatic – May require international protection Figure 38.9B Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 38.9 Protected areas are established to slow biodiversity loss • Biodiversity hot spots – Have large concentrations of endemic species – Provide an opportunity to protect many species in very limited areas Equator Figure 38.9A Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Preservation The Yellowstone to Yukon Conversation Initiative seeks to preserve biodiversity by connecting protected areas Yellowstone to Yukon Ecoregion 38.10 YUKON TERRITORY NORTHWEST TERRITORIES ALBERTA BRITISH COLUMBIA –Is an international research and conservation effort that seeks to connect reserves and protect species and ecosystems YELLOWSTONE TO YUKON CONSERVATION INITIATIVE LEGEND MONTANA Major Highways WASHINGTON Protected areas Y2Y Ecoregion 70 0 140 280 km OREGON Figure 38.10A Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings IDAHO WYOMING • Grizzly bears and gray wolves – Are two species that may benefit from this initiative Figure 38.10B, C Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Restoration • Large-scale restoration project – Attempt to restore damaged landscapes Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 38.12 The Kissimmee River Restoration Project – Is restoring river flow and wetlands, and improving water quality and wildlife habitat Former canal Figure 38.12A, B Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Protection Zoned reserves are an attempt to reverse ecosystem disruption 38.13 • Zoned reserves – Are undisturbed wild-lands surrounded by buffer zones of compatible economic development Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings • Costa Rica – Has established many zoned reserves Nicaragua Caribbean Sea Costa Rica Buffer zones supply steady lasting supply of forest products, water, hydro electric power etc. Supports sustainable agriculture While maintaining 80% native species and nature as a resource for tourism. National parkland Buffer zone Pacific Ocean Figure 38.13A, B Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Zoned reserves •Work because • They involve partnerships – among national and local governments, non-government organizations, and citizens • They are NOT damaging human welfare – Infant mortality is down – Life expectancy is up – Living conditions have improved – Literacy rate is very high Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings 38.14 Sustainable development is the ultimate goal • Sustainable development – Seeks to improve the human condition while conserving biodiversity – Depends on increasing and applying ecological knowledge as well as valuing our linkages to the biosphere We must understand that natural processes sustain us. The goal is for each generation to inherit enough natural and economic resources and a stable environment. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Figure 38.14 Saving the Tiger • Tigers once roamed across Asia – But the arrival of humans brought competition for food, and also hunters Myanmar tiger photographed by a remote “camera trap” Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Another example of success.. •Conservation efforts – Are providing protection for tigers in Myanmar so their populations can increase •The efforts to save tigers – Reflect a worldwide struggle to preserve biodiversity, the diversity of living things. Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Hukawng Valley, Myanmar