Chapter 38 Conservation Biology

Transcription

1 Chapter 38 Conservation Biology PowerPoint Lectures for Biology: Concepts & Connections, Sixth Edition Campbell, Reece, Taylor, Simon, and Dickey Copyright 2009 Pearson Education, Inc. Lecture by Brian R. Shmaefsky

2 Introduction: Saving the Tiger Conservation biology is a goal-oriented science It seeks to counter the biodiversity crisis It can focus on a single species It can also protect many species at once by preserving habitats and ecosystems Conservation biology touches all levels of ecology From a single tiger To the forest it roams Copyright 2009 Pearson Education, Inc.

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6 THE BIODIVERSITY CRISIS Copyright 2009 Pearson Education, Inc.

7 38.1 Biodiversity is a vital resource that is being lost Scientists estimate that the Earth has anywhere from 1.8 to 200 million species It is difficult to estimate species loss Species loss may be 1,000 times higher than in the past 100,000 years Copyright 2009 Pearson Education, Inc.

8 38.1 Biodiversity is a vital resource that is being lost Scientists are concerned about the ecological changes that underlie biodiversity loss Ecologists point out the services provided by the biodiversity of ecosystems Copyright 2009 Pearson Education, Inc.

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10 38.2 Biodiversity includes genetic, species, and ecosystem diversity Biodiversity has three levels Genetic diversity Species diversity Ecosystem diversity Copyright 2009 Pearson Education, Inc.

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12 38.2 Biodiversity includes genetic, species, and ecosystem diversity Endangered species One that is in danger of extinction throughout all or a significant portion of its range Protected by Endangered Species Act Threatened species Those likely to become endangered in the foreseeable future Copyright 2009 Pearson Education, Inc.

13 38.2 Biodiversity includes genetic, species, and ecosystem diversity 93% of coral reefs were damaged by human activities 40 50% of the reefs are home to one-third of marine fish species These fish could be lost in the next 30 to 40 years Video: Coral Reef Copyright 2009 Pearson Education, Inc.

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15 38.3 Habitat destruction, invasive species, and overexploitation are major threats to biodiversity Human alteration of habitats poses the greatest threat to biodiversity Habitation alteration is caused by Agriculture Urban development Forestry Mining Environmental pollution Copyright 2009 Pearson Education, Inc.

16 38.3 Habitat destruction, invasive species, and overexploitation are major threats to biodiversity Invasive species rank behind habitat destruction as a threat to biodiversity Invasive species Compete with native species Prey on native species Parasitize native species Copyright 2009 Pearson Education, Inc.

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18 38.3 Habitat destruction, invasive species, and overexploitation are major threats to biodiversity Overexploitation is the third major threat to biodiversity Overharvesting has threatened Rare trees Fish Bison Hunting of wild animals for bushmeat is depleting biodiversity worldwide Copyright 2009 Pearson Education, Inc.

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20 38.4 CONNECTION: Pollution of the environment compounds our impact on other species The global water cycle can transport pollutants Pesticides used on land Sulfur and nitrogen oxides emitted into the atmosphere Gradually thinning ozone layer Release of chlorofluorocarbons from aerosol cans and manufacturing Nutrient pollution from fertilizer and wastes Linked to summer dead zone in the Gulf of Mexico Copyright 2009 Pearson Education, Inc.

21 38.4 CONNECTION: Pollution of the environment compounds our impact on other species Pollutants in a food chain can lead to biological magnification Copyright 2009 Pearson Education, Inc.

22 Concentration of PCBs Herring gull eggs 124 ppm Lake trout 4.83 ppm Smelt 1.04 ppm Zooplankton ppm Phytoplankton ppm

23 38.5 CONNECTION: Rapid warming is changing the global climate The scientific debate about global warming is over Global temperature has risen 0.8 C in the last 100 years 0.6 C of that increase occurred in the last three decades 2 to 4.5 C increases are likely by the end of the 21st century Global warming most evident in arctic Shrinking sea ice Thinning ice sheets Melting permafrost Copyright 2009 Pearson Education, Inc.

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26 38.6 CONNECTION: Human activities are responsible for rising concentrations of greenhouse gases Atmospheric CO 2 did not exceed 300 ppm for 650,000 years Atmospheric CO 2 is approximately 385 ppm today High levels of methane and nitrous oxide also trap heat Copyright 2009 Pearson Education, Inc.

27 CO 2 (ppm), N 2 O (ppb) CH 4 (ppb) Carbon Dioxide (CO 2 ) Methane (CH 4 ) Nitrous Oxide (N 2 O) Year 600

28 Atmosphere Photosynthesis Fossil fuel Ocean

29 38.7 Global climate change affects biomes, ecosystems, communities, and populations Terrestrial biomes determined by temperature and rainfall Changing as a consequence of global warming Distributions of populations and species also changing Disappearance of many species being caused by changing climate Climate change affects seasonal events in some plants and animals Copyright 2009 Pearson Education, Inc.

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32 38.8 EVOLUTION CONNECTION: Global climate change is an agent of natural selection Global climate change drives natural selection of some organisms Most of this selection is attributed to phenotypic plasticity Altering phenotype in response to environmental conditions Within the normal range of genetic expression Can involve genetic shifts that change a species Prevents extinction of some species Copyright 2009 Pearson Education, Inc.

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34 38.8 EVOLUTION CONNECTION: Global climate change is an agent of natural selection Red squirrels in Canada Natural selection to coordinate breeding time with food availability Copyright 2009 Pearson Education, Inc.

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36 CONSERVATION BIOLOGY AND RESTORATION ECOLOGY Copyright 2009 Pearson Education, Inc.

37 38.9 Protecting endangered populations is one goal of conservation biology Habitat loss Population fragmentation A harmful effect of habitat loss Splitting and isolation of portions of populations Can lead to extinctions Copyright 2009 Pearson Education, Inc.

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40 38.9 Protecting endangered populations is one goal of conservation biology Proactive conservation strategies attempt to stop declines in populations Recovery of the red-cockaded woodpecker From near-extinction to sustainable populations Results from providing its key habitat factors Copyright 2009 Pearson Education, Inc.

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42 38.10 Sustaining ecosystems and landscapes is a conservation priority Conservation biology priority Past efforts Today Saving individual species Biodiversity of ecosystems Landscape ecology Dynamics of a collection of ecosystems Copyright 2009 Pearson Education, Inc.

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45 38.10 Sustaining ecosystems and landscapes is a conservation priority Edges can fragment ecosystems Fragmentation is corrected with movement corridors Copyright 2009 Pearson Education, Inc.

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47 38.11 Protected areas are established to slow the loss of biodiversity Conservation biology focuses on biodiversity hot spots Have a large number of endangered and threatened species Have a concentration of endemic species Hot spot designation favors the most noticeable organisms Copyright 2009 Pearson Education, Inc.

48 Equator

49 38.11 Protected areas are established to slow the loss of biodiversity Migratory species pose a special problem for conservationists Monarch butterflies occupy many areas Sea turtles travel great distances Reserves are set up to protect biodiversity 7% of world s land is in various forms of reserves Copyright 2009 Pearson Education, Inc.

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51 38.12 Zoned reserves are an attempt to reverse ecosystem disruption Zoned reserve Extensive region of land with one or more areas undisturbed by humans Contributes to sustainable development Long-term prosperity of human societies and the ecosystems Provide an economic base for people living there Copyright 2009 Pearson Education, Inc.

52 38.12 Zoned reserves are an attempt to reverse ecosystem disruption Zoned reserves are used in Costa Rican conservation Copyright 2009 Pearson Education, Inc.

53 Nicaragua Caribbean Sea Costa Rica National parkland Buffer zone Pacific Ocean

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55 38.13 CONNECTION: The Yellowstone to Yukon Conservation Initiative seeks to preserve biodiversity by connecting protected areas Yellowstone to Yukon Conservation Initiative Created a string of parks and reserves 3,200-km wildlife corridor Alaska across Canada to northern Wyoming Included introduction of wolf populations Sparked angry protests from ranchers Copyright 2009 Pearson Education, Inc.

56 YUKON TERRITORY NORTHWEST TERRITORIES Whitehorse ALBERTA Pacific Ocean BRITISH COLUMBIA Calgary Vancouver Spokane WASHINGTON MONTANA Bozeman OREGON IDAHO Jackson WYOMING

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59 38.14 CONNECTION: The study of how to restore degraded habitats is a developing science Restoration ecology Uses ecological principles to restore environments Restoring environments Bioremediation Using organisms to detoxify polluted ecosystems Replanting native vegetation Repairing waterways and wetlands Copyright 2009 Pearson Education, Inc.

60 Lake Kissimmee Widened canal Water control structure remaining Water control structure removed River channel restored Phase 1 completed Detail Atlantic Ocean Kissimmee River Floodplain Canal backfilled Water control structure to be removed in Phase 2 Gulf of Mexico FLORIDA 0 10 Miles Lake Okeechobee

61 Former canal

62 38.15 Sustainable development is an ultimate goal Biosphere is made of complex interconnections Sensible decisions needed to conserve these networks Must work for a sustainable future Sustainable development depends on continued research and application Copyright 2009 Pearson Education, Inc.

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64 Habitat destruction Invasive species Overexploitation

65 Conservation biology seeks to conserve may involve (a) ecosystems and landscapes (b) may be protected in attempt to restore which uses nature reserves restoration projects (c) need to identify and support may be (d) to detoxify or replenish degraded ecosystems minimum viable population size (e) which support sustainable development

66 You should now be able to 1. Explain why biodiversity must be protected 2. Describe the three components of biodiversity 3. Explain the major factors that threaten biodiversity 4. Explain the consequences of global climate change 5. Describe major strategies used in conservation biology 6. Explain the principles of sustainable conservation practices Copyright 2009 Pearson Education, Inc.