Conservation of Biodiversity Chapter 40

Conservation biology Biodiversity!! Emerged in response to a crisis At least 10–20% of all species now living most likely will become extinct in the next 20–50 years Bioinformatics

Conservation biology Supports following ethical principles: Biodiversity is desirable for the biosphere and, therefore, for humans Extinctions, due to human actions, are undesirable Complex interactions in ecosystems support biodiversity and are desirable Biodiversity from evolutionary standpoint has value in and of itself, regardless of practical benefit

Biodiversity Extinction Endangered species Threatened species Variety of life on Earth Between 10 and 50 million species may exist Extinction Of the described species, nearly 1,200 in the United States and 40,000 worldwide are in danger of extinction Endangered species Threatened species

Understanding Biodiversity Genetic diversity variations among the members of a population Ecosystem diversity dependent on interactions of species at a locale Conserve species that play a critical role in an ecosystem Saving an entire ecosystem can save many species Landscape diversity interacting ecosystems within one landscape Fragmentation reduces can disrupt seasonal behaviors Distribution of Biodiversity Biodiversity not evenly distributed throughout the biosphere biodiversity hotspots contain unusually large concentrations of species

Disrupted ecosystem in Flat-head Lake, Montana

Direct Value of Biodiversity Wildlife Has Medicinal Value Most prescription drugs in the United States originally derived from living organisms

Direct Value of Biodiversity Wildlife Has Agricultural Value Crops are derived from wild plants that have been modified Biological pest controls are often preferable to chemical pesticides

Direct Value of Biodiversity Wildlife Has Consumptive Use Value freshwater and marine harvests depend on the catching of wild animals Provides a variety of other products that are sold in the marketplace worldwide

Indirect Value of Biodiversity Biogeochemical Cycles Dispose of Waste Biodiversity contributes to workings of water, carbon, phosphorus, and nitrogen cycles Natural Areas Provide Fresh Water, Prevent Soil Erosion, and Regulate Climate Water-holding capacity of forests and wetlands reduces the possibility of flooding Intact ecosystems naturally retain soil and prevent erosion Ecotourism Is Enjoyed by Many In U.S., people spend $4 billion each year on ecotourism

Wildlife Extinctions Habitat loss Introduction of alien species Pollution Overexploitation Disease

1. Habitat loss 1,880 threatened and endangered species in U.S. 85% of cases Focus on tropical rain forests and coral reefs Loss of habitat also affects freshwater and marine biodiversity Coastal degradation mainly due to the large concentration of people living on or near the coast 60% of coral reefs have been or are on verge of destruction

2. Alien Species Colonization Horticulture and agriculture Nonnative members brought into new ecosystems through Colonization Europeans brought various familiar species with them when they colonized new places Horticulture and agriculture Aliens have escaped from cultivated areas Accidental transport Global trade and travel Aliens on Islands Islands are particularly susceptible to environmental discord caused by the introduction of alien species

2. Alien Species Everglades National Park, Florida Pythons Caiman Wooly rat Monitor lizards

3. Pollution Acid deposition Environmental change that damages lives and health of organisms Acid deposition sulfur dioxide from power plants nitrogen oxides in automobile exhaust converted to acids when they combine with water vapor in the atmosphere Eutrophication Overenrichment algae blooms occur and upon death, the decomposers break down the algae in so doing, they use up oxygen

3. Pollution Ozone depletion Organic chemicals Global warming **** Ozone shield absorbs most of the wavelengths of harmful ultraviolet (UV) radiation so they do not strike the Earth Organic chemicals used in products ranging from pesticides to dishwashing detergents, cosmetics, plastics, etc Global warming **** A 1 meter rise in sea level could inundate 25–50% of U.S. coastal wetlands Bleaching coral reefs

4. Overexploitation Number of individuals taken from a wild population so great that the population becomes severely reduced in number Positive feedback cycle Smaller population Greater incentive to capture few remaining organisms Poachers Overexploited 11 of 15 major oceanic fishing areas Fish are a renewable resource More efficient fishing fleets to decimate fishing stocks

5. Diseases Due to encroachment of humans on habitat and other general interventions Pollution can weaken organisms more susceptible to disease May be due to alien species Chytrid fungus

Conservation Techniques Habitat Preservation Habitat Restoration

Habitat Preservation Keystone species influence the viability of a community Extinction of a keystone species can lead to other extinctions and a loss of biodiversity Metapopulation population subdivided into several small, isolated populations Habitat fragmentation by humans Landscape Preservation Landscape protection for one species is often beneficial for other wildlife that share the same space

Habitat Restoration Restoration ecology Subdiscipline of conservation biology Seeks scientific ways to return ecosystems to former state Three principles have so far emerged: It is best to begin as soon as possible before remaining fragments of the original habitat are lost Once the natural history is understood, it is best to use biological techniques that mimic natural processes to bring about restoration Goal is sustainable development, ability of an ecosystem to maintain itself while providing services to human beings

Habitat Restoration The Everglades Located in southern Florida Beginning of 20th century, settlers began to drain land to grow crops A restoration plan has been developed that will sustain the Everglades ecosystem, while maintaining the services society requires The Everglades is to receive a more natural flow of water from Lake Okeechobee

Global Climate Change Emissions of greenhouse gases are accelerating From 2000–2005 global CO2 emissions increased four times faster than in the preceding 10-year span

Climate Change In many plants and animals, life cycle events are triggered by Warming temperatures Day length As global temperatures warm, and day length remains steady, natural interactions may become out of sync Plants may bloom before pollinators have emerged Eggs may hatch before dependable food sources are available

Human Impact on Biomes Sustainability goal of developing, managing, and conserving Earth’s resources meet the needs of people today without compromising the ability of future generations to meet their needs Student Misconceptions and Concerns 1. Before addressing specific biomes, consider discussing some specific details about global weather patterns with references to the major factors that influence your local weather. Depending upon where you live, students may not understand the influences of mountains, large bodies of water, and latitude on weather. 2. Students may expect that similar biomes have similar species, a common misperception. As the text notes, the similarities in organisms between widely separated but similar biomes is much more likely due to convergent evolution. Teaching Tips 1. Before lecturing about rivers and streams, ask students to speculate how the qualities of a stream change from its source to the point where it joins a larger body of water many kilometers downstream. In particular, how does water temperature, water clarity, water speed, and the types of fish compare as the water flows away from its source? 2. The removal and deposition of sediment in a river or stream reveals the importance of the speed of water. Near the out edge of a curve, a river or stream will erode the bank. However, when the river slows or along the slower inside of curves, sediment tends to deposit. The result is the winding nature of mature rivers. A satellite image of the Mississippi river reveals the extensive curvature of this old system. 3. Throughout the text, the sun has been generally considered as the primary energy input to ecosystems. Hydrothermal vent communities are a clear exception. Some students might enjoy additional details about the nature of these ecosystems and the roles they might have played in the early evolution of life on Earth. One source of good Internet information about hydrothermal vent communities is found at: www.csa.com/discoveryguides/vent/websites.php. 4. The turnover of lakes and ponds in the fall often results in noticeable changes that students may have observed. Fish kills and distinct changes in the colors and smells of the water may have been noticed by students in your course (depending upon your particular location). If you are addressing this subject in the fall or early winter, you might have students watch for this phenomenon. 5. Many web sites introduce the diversity of biomes with varying degrees of detail and imagery. Many related sites are targeted towards pre-college students. The following site lists links related to biomes (www.aresearchguide.com/biomes.html) 6. Consider preparing a chart that will help your students compare the characteristics of the major terrestrial biomes. Helping students learn how to organize information may still be needed at the beginning levels of college. 7. Challenge your students to identify unpredictable natural disturbances in the terrestrial biomes examined. How is each biome adapted to recover? What components of each biome are dependent upon these natural disturbances? Exploring the role of disturbances in ecosystems may provide hope to students who may be saddened by human impacts on biomes. 8. In the 1960s and early 1970s, movies about the American west were produced in portions of Europe. Relying upon similar biomes in Europe and North America, these “spaghetti westerns” were made to look as if they were filmed in the American west. A Google search of “spaghetti westerns” will produce links to websites devoted to this genre of film. 9. A discussion of the movements of water through your local community might help students relate to the concept of global water cycling at a local level. Students could be asked to consider all of the possible inputs of water into your community and the possible routes of exit. Students may not realize that it is possible that the outflow of water from one community leads to the inflow of water in a community downstream.

Figure 18.39 Satellite photos of the Rondonia area of the Brazilian rain forest 1975 2001 Figure 18.39

The Greenhouse Effect and Global Warming Greenhouse gases Include CO2, water vapor, and methane Are transparent to solar radiation Absorb or reflect heat Contribute to increases in global temperatures Student Misconceptions and Concerns 1. The thinning of the ozone layer is a related but separate issue from global warming. Students often confuse these issues and think of them as somehow the same problem. 2. The general tendency to discounts one’s impact on global issues and concerns can be difficult. How can one person matter? Consider addressing this perspective and involving your class in a related discussion to consider including the concept of a person’s carbon footprint. Teaching Tips 1. Identify local issues that are related to the topics addressed in this chapter. What can be done in and around your campus to make meaningful change? 2. One of many carbon footprint calculators can be found at the website for the Nature Conservancy. www.nature.org/initiatives/climatechange/calculator/

Some heat energy escapes into space Sunlight Atmosphere Radiant heat trapped by greenhouse gases Figure 18.43a The greenhouse effect

Carbon dioxide (CO2) (ppm) 400 350 Carbon dioxide (CO2) (ppm) 300 Figure 18.45 Atmospheric concentration of CO2 250 500 1000 1500 2000 Year

Looking to Our Future Emissions of greenhouse gases are accelerating. From 2000–2005 global CO2 emissions increased four times faster than in the preceding 10-year span. In addition, eating locally grown fresh foods may lower the greenhouse gas emissions that result from food processing and transportation. Student Misconceptions and Concerns 1. The thinning of the ozone layer is a related but separate issue from global warming. Students often confuse these issues and think of them as somehow the same problem. 2. The general tendency to discounts one’s impact on global issues and concerns can be difficult. How can one person matter? Consider addressing this perspective and involving your class in a related discussion to consider including the concept of a person’s carbon footprint. Teaching Tips 1. Identify local issues that are related to the topics addressed in this chapter. What can be done in and around your campus to make meaningful change? 2. One of many carbon footprint calculators can be found at the website for the Nature Conservancy. www.nature.org/initiatives/climatechange/calculator/

Our future? carbon (ecological) footprint amount of greenhouse gas emitted as the result of the actions of a single individual reduce our carbon footprints by: Reducing our use of energy Driving less Recycling