CH-5-6 Sustaining Biodiversity: The Species Approach – Sustaining the Earth : Chapter Notes

This Document Contains Chapters 5 to 6 Chapter 5 Sustaining Biodiversity: The Species Approach Summary and Objectives 5-1 What are the trends in species extinction? Human modification of the earth’s natural ecosystems has been extensive: reducing biodiversity, eliminating the earth’s net primary productivity, strengthening some pest species and disease-causing bacteria, over harvesting natural resources, etc. CONCEPT 5-1 Species are becoming extinct 100 to 1,000 times faster than they were before modern humans evolved, and by the end of this century, the extinction rate is projected to be 10,000 times higher than that background rate.1. Distinguish between an endangered and a threatened species. List nine characteristics of extinction-prone species. 2. Compare past extinctions to present extinctions. Evaluate the reality of an extinction crisis. 3. Why do extinction experts consider the current estimates of species extinction to be conservative? 5-2 Why should we care about the rising rate of species extinction? Wild species have value, some of which has not yet been identified. We need a precautionary strategy to prevent significant decrease in the genetic, species, ecological, and functional diversity of the earth. CONCEPT 5-2 We should avoid hastening the extinction of wild species because of the ecosystem and economic services they provide, and because many people believe that these species have a right to exist regardless of their usefulness to us. 4. Describe the economic, medical, scientific, ecological, aesthetic, and recreational significance of wild species. 5. List and explain two reasons why some biologists caution us not to focus on protecting relatively large organisms with which we are most familiar? 5-3 How do humans accelerate species extinction? Humans can increase species extinction by causing degradation of habitat, introducing alien species, population growth, pollution from daily activities, and by over harvesting. CONCEPT 5-3 The greatest threats to any species are (in order) loss or degradation of its habitat, harmful invasive species, human population growth, pollution, climate change, and overexploitation. 6. Briefly explain what the acronym HIPPCO stands for. 7. List and briefly describe eight ways humans increase the rate of extinction, indicating which of these has the most impact. 8. Give two examples of the harmful effects of nonnative species that have been introduced both deliberately and accidentally. 9. State two examples of what can be done to decrease the incidence and impacts of invasions of nonnative species? 5-4 How can we protect wild species from extinction resulting from our activities? Mankind must live with a precautionary principle: prevent harm even if a cause-and-effect relationship has not been established. A low throughput economy reduces the use of matter and energy resources in reusing and recycling nonrenewable resources, reduces unnecessary consumption, emphasizes waste reduction, encourages pollution reduction, and controls population growth. CONCEPT 5-4 We can reduce the rising rate of species extinction and help to protect overall biodiversity by establishing and enforcing national environmental laws and international treaties, creating a variety of protected wildlife sanctuaries, and taking precautionary measures to prevent such harm. 10. State and briefly describe the most far-reaching international treaty to protect wildlife. 11. Should the Endangered Species Act be strengthened or weakened? Defend your position. 12. Briefly assess the usefulness of wildlife refuges, gene banks, botanical gardens, and zoos in protection of wildlife. List three qualities that should be given priority in defending wildlife. 13. List and briefly describe four things that you can do as an individual to help prevent the premature extinction of species. 14. Describe how wildlife populations can be managed. Evaluate whose interests are generally the most influential in determining wildlife management priorities. Key Terms biological extinction endangered species threatened species instrumental value intrinsic value existence value HIPPCO Outline 5-1 What Are the Trends in Species Extinction? The balance between forming new species and the extinction of existing species determines earth's biodiversity. The three types of species extinction are local, ecological, and biological. A. Local extinction occurs when a species disappears from an area it once inhabited but is found elsewhere in the world. B. Ecological extinction occurs when the number of members of a particular species is so low that they cannot fulfill their ecological roles in their biological communities. C. Biological extinction occurs when a species has disappeared from the earth. 1. The passenger pigeon represents lost natural capital, primarily because of over hunting and habitat destruction directly attributable to man. (See Case Study: The Passenger Pigeon: Gone Forever, p. 93) 2. Scientific studies show that human activities are causing extinctions: consuming resources, filling wetlands, loss of forests, degrading aquatic ecosystems, etc. D. Biologists use measurements and models to estimate extinction rates. (See Science Focus: Estimating Extinction Rates.) 1. Predicting future extinction rates is difficult because: a. Extinction of a species usually takes a long time and is difficult to document. b. We do not know the precise number of species on the earth and the rate of species extinction. c. Biologists know little about the nature and ecological roles of most identified species. 2. Human activities affect extinction rates. a. Currently, the rate of extinction is from 1,000–10,000 times the rate before mankind existed. b. Using estimated extinction rates, by 2050 25% of the world’s present plant and animal species will be gone; 50% will vanish by 2099. 3. Greater extinction rates than predicted are likely because of several factors. a. Species loss and biodiversity loss will likely increase because of exponential population growth. b. Biologically diverse area extinction rates may be as high as 25–-50%. The extinction rates in these “hot spots” deserve special attention. c. Possible colonization sites for new species are being eliminated, degraded, and simplified by human activities so that new species cannot arise. By reducing this rate of speciation, we are creating a speciation crisis, which may contribute to dominance of the world by species with survival power—cockroaches, rats, and weeds—and contribute to the permanent decline of earth’s variety of species. E. Classifying species 1. Endangered species are those that could become extinct fairly soon because there are so few survivors. 2. A threatened/vulnerable species is likely to become extinct because its numbers are rapidly declining. 3. http://www.iucnredlist.org/ is an online database that lists the world’s threatened species. 4. Such threatened animals tend to be the big, slow, and tasty ones whose valuable parts can be sold. 5-2 Why Should We Care about the Rising Rate of Species Extinction? Wild species have value—economic and ecological—that is important to the earth. A. We are destroying species biodiversity more quickly than new species can evolve. It will take 5–10 million years for speciation to rebuild the animals and plants we will destroy in 100 years. B. Some of the economic and ecological benefits (instrumental value) of present species have not even been identified; we are destroying our chance for a future. 1. Medicinal properties are found in many plants and some animals. 2. Genetic information in species helps them adapt and produce new species. This information can be used to develop food and medicines for people. 3. Recreational use and pleasure are provided by plants and animals. 4. Eco-tourism generates money to help poor countries; preserving plants and animals is much more economically wise than destroying them. a. A male lion skin is worth $1,000; a male lion living for seven years produces $515,000 in tourist dollars. b. Elephant tusks are worth many times less than the ecotourist revenue generated over its lifetime. c. C. Some people would protect some species, not necessarily all of them. Others believe in the intrinsic or existence value of every species having the right to exist free from human interference. 5-3 How Do Humans Accelerate Species Extinction? There are several causes of depletion and premature extinction of wild plants and animals. The acronym HIPPCO describes these causes. A. The loss, degradation, and fragmentation of habitat is the greatest threat to a species. 1. Deforestation in tropical forests is the greatest species eliminator. 2. Temperate biomes have been compromised by widespread development. 3. Endemic species are those found nowhere else on earth and are often found in island habitats. Habitat islands are habitats surrounded by different ones, such as a national park surround by logging or mining activities. a. Habitat fragmentation leads to species vulnerability to predators, disease, etc. b. Species are limited in their ability to colonize new areas, and find mates and food. 4. Bird species are excellent environmental indicators; they respond quickly to environmental change and are easy to track. B. Introduction of alien species can lead to native species extinction. Nonnative species introduction into an ecosystem can cause ecological and economic harm. 1. The alien species can be introduced accidentally or deliberately. 2. Some of these species threaten and endanger native species. (See Case Study: Burmese Pythons Eating their Way through the Florida Everglades) a. They have no natural predators, competitors, or pathogens in their new habitat. b. They can trigger ecological disruptions, such as the wild African honeybee, Argentina fire ant, or the Formosan termite. 3. The best control is to prevent the nonnative species from being introduced. a. Identify the types of ecosystems that are vulnerable to invaders and identify the characteristics that allow the nonnative species to become successful invaders. b. Inspect imported goods. c. Identify harmful invader species and pass international laws that prohibit their transfer from one country to another. d. Require ships to clean or sterilize their ballast water to kill invader organisms. C. Pollution from human activities undermines habitats and the lives of species. 1. Climate change threatens a number of species with extinction. (See Case Study: Polar Bears and Climate Change) a. Changes in climate will alter the world’s habitats. b. Species may not have enough time to adapt to the climate change and will die. 2. Pollution undermines all living species. a. Chemicals degrade the environment and kill species. b. Pesticides are especially deadly to honeybees, birds, and fish. c. DDT is an example of harm to species through both bioaccumulation and biomagnifications. D. Illegal killing/capturing of wild animals also threatens them. 1. Commercial hunting and poaching must be eliminated. 2. Illegal international trade kills two-thirds of smuggled animals in transit. a. Huge profits attract organized crime. b. Poverty forces people to trap and sell animals for minimal payback. (See Case Study: A Disturbing Message from the Birds, for an illustration of how all of these human impacts are harming bird populations.) 5-4 How Can We Protect Wild Species from Extinction Resulting from Our Activities? A. Treaties help protect endangered/threatened species, but enforcement is hard and punishment inadequate. B. The 1975 Convention on International Trade in Endangered Species (CITIES) protects 900 species from commercial trade and restricts international trade for 34,000 species that may become threatened. 1. Enforcement is difficult. 2. Many countries are not signatories and still trade in animals. 3. The Convention on Biological Diversity (CBD) binds governments to reverse the global decline in biological biodiversity. The United States has not ratified this treaty. C. Two laws help the U.S. control imports and exports of endangered wildlife and wildlife products. 1. The Endangered Species Act of 1973 (ESA) identifies and lists endangered species in the U.S. and abroad. a. Identification of endangered, threatened ocean and land species is made by the National Marine Fisheries Service and/or the US. Fish and Wildlife Service. b. Habitats of endangered species must be protected. 2. A 2000 study by the Nature Conservancy found one-third of the U.S. species are at risk of extinction. 3. Landowners are encouraged to develop habitat conservation plans to protect species on private land. 4. Efforts have been made to repeal/weaken the Endangered Species Act. D. Successes of the Endangered Species Act are outlined in the Case Study: The U.S. Endangered Species Act 1. The only species listed are in serious danger of extinction. 2. It takes many decades to bring a species in critical condition back so that it can be removed from the list. There are no “quick fixes” for those listed. 3. Almost 40% of the species on the list are stable or improving—a good rate. 4. Much has been accomplished on a shoestring budget. 5. In order to strengthen the ESA, the U.S. National Academy of Sciences recommended that: a. The funding be increased to implement the act b. Recovery plans be developed more quickly c. Conservation plans that contain solid scientific evidence showing that they are likely to succeed be required E. Establishing wildlife refuges and protected areas 1. The sanctuary approach began in 1903 and is still being used to protect wild species. 2. 555 federal refuges protect wildlife, but the habitats are deteriorating from invasive species, pollutants, and little operational or maintenance funding. 3. Gene banks, botanical gardens and farms can be used to raise threatened species and help protect species from extinction; but they are expensive to operate and funding is inadequate. F. Zoos and aquariums can help protect some endangered species, but they are both notoriously underfunded. 1. Egg pulling collects wild eggs of endangered bird species and hatches them in zoos/research centers. 2. Captive breeding takes wild animals into captivity for breeding; aiming to re-introduce the offspring back into the wild. 3. The major conservation role of zoos is to educate the public about species’ biological importance and the need to protect habitats. Zoos do not have the space to sustain the needed numbers in an animal population. G. The precautionary principle states that when we have substantial preliminary evidence that an activity can harm human health or the environment we should take measures to prevent or reduce such harm even in the absence of full cause and effect relationships. Teaching Tips 1. More and more classrooms are now being equipped with technology that enables instructors to download relevant videos from the internet to share with their students. In addition to the supplementary BBC News Videos, becoming familiar with websites that offer free downloads can be a wonderful way to supplement classroom learning, especially when working with a limited budget. 2. One popular site for accessing videos is youtube.com. Additionally, using a video search engine such as video.google.com will display all videos found on the internet, including those found on YouTube, that are relevant to the topic searched. An advanced video search is also available with this video search engine. 3. Videos effectively allow students to quickly travel through time and space, exposing them to issues that they would otherwise not able to experience firsthand. Using short videos can also serve as an attention-getting device to draw students into the lesson. 4. Free downloadable videos can also be assigned as homework. Encourage students to share videos they find with the class as this is an excellent way to get students interested in the class material. Sharing also fosters a learning environment in which all students are welcome to contribute. 5. Rather than reinventing the wheel by making follow-up activities for the videos, first try doing a simple internet search for instructor or educator materials and lesson plans. Additionally, many videos now have online companion websites with free downloadable classroom activities. 6. Remember to download videos before class begins to ensure that the video is ready when needed. Downloading videos can sometimes take a few minutes, and so it’s better to do this ahead of time and maximize the time on task within the classroom. Doing this will also help avoid other technological errors during class time. Topics for Term Papers and Discussion Conceptual Topics 1. Significance of wildlife. Medicines derived from plants and animals; commercial products from wildlife; aesthetic and recreational significance of wildlife; ecological significance of wildlife. 2. Endangered and threatened wildlife. Tropical deforestation and species extinction; the international trade in endangered species and exotic pets; lead poisoning in waterfowl and the American bald eagle; Florida’s alien species problem; the California condor; the Florida manatee; the blue whale. 3. Protecting wildlife. Gene banks; zoos and captive breeding programs; habitat management; artificial reef-building materials and methods. Attitudes & Values 1. Do you believe that humans have a duty to subdue wild nature to provide food, shelter, and other resources for people and to provide jobs and income through increased economic growth? 2. Do you believe that every living species has a right to exist, or at least struggle to exist, simply because it exists? 3. Do you believe that we have an obligation to leave the earth for future generations of humans and other species in as good a shape as we found it, if not better? Did past generations do this for you? 4. Should animals be used for medical research? As sources of organs for surgical implants in humans? As sources of food, fur, fat, oils, and other commercially valuable products? 5. Are extremist tactics by Greenpeace and Earth First! Necessary or justifiable? 6. Should sport hunting be used as a wildlife management tool? Action-Oriented Topics 1. Individuals. Scientific methods for estimating wildlife populations and successional stage of ecosystems. 2. Groups. Ducks Unlimited; the National Wildlife Federation; the Audubon Society; Greenpeace; Earth First! 3. National. America’s National Wildlife Refuge System. 4. Global. The World Wildlife Fund. Activities and Projects 1. Are there zoos, aquariums, botanical gardens, or arboretums in your locale that are operating programs designed to increase the populations of endangered species? If so, invite a spokesperson to explain one or more of these programs to your class. 2. Ask your students to bring to class and share paintings, sketches, poetry, songs, and other artistic creations depicting the beauty and wonders of wildlife. 3. Have a game warden address your class about management of populations of fish and animals that are hunted for sport. 4. Compile a list of the wildlife species in your locale that have been officially designated as threatened or endangered. As a class project, find out what specific actions are being taken to assist these species. 5. As a class, examine and evaluate the goals of the World Conservation Strategy. Develop objectives that could help implement the goals that are agreed upon by the class. BBC News Videos The Brooks/Cole Environmental Science Video Library with Workbook, Featuring BBC Motion Gallery Video Clips, 2011. DVD ISBN: 978-0-538-73355-7 (Prepared by David Perault) Kalahari Desert Could Double in Size Half the World Denied Basic Sanitation Darwin's Galapagos Under Threat China's Deadly Pollution How Exotic Species Are Devastating Hawaii's Native Fauna Are We Facing an Extinction Crisis? Suggested Answers for Critical Thinking Questions 1. Student answers will vary. Some examples include taking steps to reduce personal excessive and wasteful resource consumption, avoid purchasing exotic pets and decorative plants, and avoid overusing pesticides. 2. Aspects of a person’s lifestyle that directly or indirectly contribute to the premature extinction of some bird species may include overuse of resources, introduction of nonnative species, and commercial hunting and fishing. Things that can be done to reduce the premature extinction of birds include reducing human population growth, restricting deforestation, decreasing pollution emission, and efforts to avoid the introduction of nonnative species. 3. Student answers will vary. While some students may profess belief in inherent right for species to survive without human interference, that view may be challenged (or at least be more challenging to profess) when species that are harmful to humans (mosquito, infections bacterial) are considered. 4. Aldo Leopold’s quote relates to the chapter material on the precautionary principle. We need to take steps to maintain biodiversity even if some of the cause-and-effect relationships have not been fully established scientifically. 5. Student answers will vary. The range of opinions represented here are common in a community – discussion of how these attitudes support or conflict with each other and inform policy decisions is of interest. 6. Student answers will vary. Student answers should explore multiple sides of the issue – economic, environmental, social, business, etc. There are no right answers, but the way forward in real life lies in compromise. 7. Student answers will vary. Chapter 6 Sustaining Biodiversity: The Ecosystem Approach Summary and Objectives 6-1 What are the major threats to forest ecosystems? Human activities have caused or contributed to the premature extinction of hundreds of species. They have, in addition, degraded from 50–83% of the earth’s land surface. CONCEPT 6-1 Unsustainable cutting and burning of forests, along with the projected effects of climate change, are the chief threats to forest ecosystems. 1. Distinguish between old-growth forest and second-growth forest. List five reasons why forests are commercially important. List five reasons why forests are ecologically important. 2. List three ways to help reduce the interlocking problems of tropical deforestation and the fuelwood crisis. 3. State the rates of tropical deforestation. List five ways that tropical forests touch lives in the temperate zones. List three factors underlying causes of tropical deforestation. List eight human activities that actually destroy the tropical forests. List five ways that tropical deforestation could be reduced. 4. Describe the advantages and disadvantages of clear-cutting a forest ecosystem. 5. Describe the natural capital of forests in terms of ecological and economic services. 6-2 How should we manage and sustain forests? In order to preserve natural environments, countries must establish and manage nature reserves as well as wilderness areas. CONCEPT 6-2 We can sustain forests by emphasizing the economic value of their ecosystem services, removing government subsidies that hasten their destruction, protecting old-growth forests, harvesting trees no faster than they are replenished, and planting trees. 6. Describe the steps in forest management. List and summarize the goals for three types of tree harvesting. 7. Define and describe at least seven characteristics of sustainable forestry. 6-3 How should we manage and sustain parks and nature reserves? Sustainably managing and protecting wilderness helps preserve large areas of biodiversity. CONCEPT 6-3 Sustaining biodiversity will require more effective protection of existing parks and nature reserves as well as the protection of much more of the earth's remaining undisturbed land areas. 8. Briefly describe the extent of national parks worldwide. Describe a major problem of national parks. State three steps that could improve the national park system. Evaluate the wolf controversy, take a stand, and defend it. 9. Define wilderness. Describe a biosphere reserve. State one problem of wilderness areas and describe how that problem could be managed better. 10. Compare the status of U.S. forests from 1900 and the present. Summarize how U.S. forests are currently managed. List ways environmentalists recommend to reform federal forest management, including: (a) two changes in resource-use practices, (b) three economic strategies, and (c) three political strategies. 6-4 What is the ecosystem approach to sustaining terrestrial biodiversity? We must focus on protecting and sustaining ecosystems and the biodiversity within them rather than on saving individual species. CONCEPT 6-4 We can help to sustain terrestrial biodiversity by identifying and protecting severely threatened areas (biodiversity hotspots), restoring damaged ecosystems, and sharing as much of the earth's land as possible with other species. 11. What is a biodiversity hotspot? Give three supporting reasons why it is important to protect such areas. 12. Define and give three examples of ecological restoration. 6-5 How can we protect and sustain marine biodiversity? Marine biodiversity must be protected in all ocean zones through marine sanctuaries and integrated coastal management. CONCEPT 6-5 We can help sustain marine biodiversity by using laws and economic incentives to protect species, setting aside marine reserves to protect ecosystems, and using community-based integrated coastal management. 13. Summarize ways to globally manage marine fisheries to prevent over fishing. 14. Define the importance of aquatic biodiversity and describe three ways to protect and sustain marine biodiversity. 6-6 How can we protect and sustain freshwater biodiversity? Everything that is done on land and in the water has some effect on freshwater aquatic systems, so they must be protected through laws, economic incentives, and restoration efforts. CONCEPT 6-6 We can help to sustain freshwater biodiversity by protecting the watersheds of lakes and streams, preserving wetlands, and restoring degraded freshwater systems. 15. Define the importance of aquatic biodiversity and describe three ways to protect and sustain freshwater biodiversity. 16. Describe three ways that freshwater ecosystems are threatened. 6-7 What should be our priorities for sustaining biodiversity? Lessons from ecology can help us in sustaining the earth’s biodiversity as we live upon it. We must understand our dependence on the earth and sun; understand that everything is inter-dependent; maximize protection of ecosystems; foresee and provide for our actions, and discontinue depleting and degrading our environment. CONCEPT 6-7 We can help to sustain the world's biodiversity by mapping it, protecting biodiversity hotspots, creating large terrestrial and aquatic reserves, and carrying out ecological restoration of degraded terrestrial and aquatic ecosystems. 17. List and briefly explain four of the priorities for protecting most of the world’s remaining ecosystems as proposed by Edward O. Wilson. Key Terms old-growth forests second-growth forests tree plantations tree farm commercial forest deforestation wilderness biodiversity hotspots ecological restoration reconciliation ecology ocean acidification Outline 6-1 Human Impacts on Biodiversity A. Forests are classified according to their age and structure into three major types. 1. Old growth/frontier forests are those that have not been seriously disturbed by human activities or natural disasters for hundreds of years. These forests are storehouses of biodiversity because of the ecological niches they provide for wildlife species. 2. Second-growth forests develop in an area after human activities or natural forces have removed the trees in an area (secondary ecological succession). 3. Tree plantations/tree farms replant and clear-cut one species of tree in a regular cycle. B. The ecosystem services that forests provide are more valuable than the trees themselves. 1. Forests help stabilize the earth’s temperature and slow global warming as part of the carbon cycle. 2. These services are worth at least $4.7 trillion per year; hundreds of times more than their economic value. C. The presence of logging roads has many negative consequences. 1. Logging roads increase erosion and sediment runoff, fragment habitats, and contribute to loss of biological diversity. 2. They expose forest to invasion by nonnative pests, diseases, and wildlife species. 3. Roads also open once-inaccessible roads to invasion by people (hunters, farmers, ranchers, and their vehicles) D. Different harvesting methods affect the continuing growth of forests. 1. In selective cutting, intermediate-aged/mature trees are cut singly or in groups. 2. Clear-cutting removes every single tree in one cutting. 3. Strip cutting removes a strip of trees along the contour of the land and spreads the cutting out over several decades. E. Deforestation is widespread across the planet and is continuing. 1. Forests have been eradicated, and those that have not disappeared have been altered and fragmented. 2. Between 1990 and 2005, the global forest cover loss rate was between 0.2% and 0.5% per year 3. These forest losses are concentrated in less-developed countries, especially Latin America, Indonesia, and Africa. F. Many old-growth forests in the U.S. have undergone reforestation by secondary ecological succession. See Case Study. 1. More wood is grown each year in the U.S. than is cut. 2. About 40% of U.S. forests are on protected lands, mostly in national forests. 3. But the U.S. is losing its old-growth and second-growth forests, replaced by biologically simplified tree plantations. This disrupts forest biodiversity and ecosystem processes. G. Tropical forests cover approximately 6% of Earth’s land, but scientists think forests once covered twice this much land. Most of the forest loss has occurred since 1950. 1. Brazil has more than 30% of the world’s tropical rain forest 2. Widespread burning and deforestation is changing weather patterns in the Amazon basin, converting the forest into a savanna. H. The causes of tropical forest destruction are complex 1. Poverty and population growth drive subsistence farmers to tropical forests where they attempt to farm. 2. Government subsidies make tropical forest resources cheap—relative to their full ecological value. 3. Degradation of forests usually follows a predictable pattern: selective logging of largest trees damages many surrounding trees. Burning is widely used for clearing forest areas, while roads, settlements, farming, and similar activities fragment forests. 4. Foreign corporations do much of the logging work, with beneficial government contracts. After the best timber has been removed, the land is often sold to ranchers who overgraze the land and then sell the degraded land to farmers for crops. 6-2 How Should We Manage and Sustain Forests? A. If the economic value of the ecological services provided by forests was included in forest-use decisions, many of the old-growth forests would not be cut. 1. Selective harvesting and using forests for recreation will help sustain forests indefinitely. 2. Certification of sustainably grown timber indicates that a company uses selective cutting and other environmentally friendly harvesting methods. 3. Up to 60% of the wood consumed in the US is wasted – improving efficiency of our wood use is an important aspect of sustainable forests. Developing tree-free paper products is also an important step toward sustainability. 4. Reducing the need to cut trees for fuel will help reduce deforestation in less-developed countries B. Goals for sustainable forestry (Fig 6-8) 1. Include ecosystem services of forests in economic estimates. 2. Identify and protect highly diverse forest areas. 3. Stop logging in old-growth forests. 4. Stop clear cutting on steep slopes. 5. Reduce road building in forests and rely more on selective and strip cutting. 6. Leave most standing dead trees and large fallen trees for wildlife habitat and nutrient cycling. 7. Put tree plantations only on deforested and degraded land. 8. Certify timber grown by sustainable methods. C. To reduce deforestation and degradation of tropical forests (Fig. 6-9): 1. Protect the most diverse and endangered areas 2. Educate settlers about sustainable agriculture and forestry. 3. Subsidize only sustainable forest use 4. Protect forests through debt-for-nature swaps and conservation concessions. 4. Certify sustainably grown timber. 5. Reduce poverty and slow population growth. 6. Governments and individuals can reforest and rehabilitate degraded tropical forests and watersheds. (See Individuals Matter: Wangari Maathai and Kenya’s Green Belt Movement) 6-3 How Should We Manage and Sustain Parks and Nature Reserves? National parks, established by governments, are popular with people all over the world. A. Several threats to national parks must have a sustainable response. 1. Parks need protection from illegal uses a. People search for wood, game animals, etc. b. Loggers, miners, and poachers take all they want from the parks. c. Park services are underfunded and understaffed to manage these challenges d. Parks are too small to sustain many large animals and often have invasive species which proliferate unchecked. 2. Many of the stresses on US public parks result from large numbers of visitors, introduction of invasive species, predators, and loss of surrounding biodiversity (See Case Study: Stresses on U.S. Public Parks, and Science Focus: Reintroducing the Gray Wolf to Yellowstone National Park) . B. Nature reserves occupy only a small part of the earth's land. 1. Ecologists believe the best way to preserve biodiversity is to create a world-wide network of protected areas. 2. Conservation biologists call for protection of 20% of the earth's land, but economic and political interests oppose this idea. Implementation requires action and funding from organizations as well as partnerships among government, businesses, and conservation organizations. 3. The buffer zone concept describes a sustainable management strategy where the inner core of a reserve is strictly protected, surrounded by two buffer zones where local people can extract resources without harming the inner core. 4. Costa Rica is rich in biodiversity and now devotes a larger proportion of its land to biodiversity conservation than does any other country. Today, the country's income largely relies on eco-tourism. See Case Study: Costa Rica – A Global Conservation Leader. C. Protecting wilderness helps preserve large areas of biodiversity. 1. Wilderness is land legally set aside in a large enough area to prevent/minimize harm from human activities. 2. Opponents of wilderness protection view this as keeping some areas economically unusual to people living today. 6-4 What is the Ecosystem Approach to Sustaining Terrestrial Biodiversity? A number of different techniques are available for rehabilitating and restoring damaged ecosystems. A. We must focus on protecting and sustaining ecosystems and the biodiversity within them rather than on saving individual species by: 1. Mapping global ecosystems and inventory species 2. Identifying terrestrial ecosystems that are resilient and that can recover 3. Locating and protecting the most endangered ecosystems and species 4. Restoring degraded ecosystems 5. Making development biodiversity-friendly by providing technical help and financial incentives B. Immediately protect terrestrial “hot spots” in the world where significant biodiversity is under immediate threat. Such hot spots are areas that are especially rich in plant and animal species not found anywhere else and that are in great danger of extinction/serious ecological disruption as well. Most of the “hot spots” are tropical forests. 1. One strategy is that of prevention: focus international efforts to establish a variety of large and small reserves in the world. 2. Most bio-diverse countries are in areas within these countries where species-rich areas are threatened. 3. See Case Study: Madagascar: An Endangered Center of Biodiversity. C. Ecological restoration is a process that repairs damage caused by humans to the biodiversity and dynamics of natural ecosystems. 1. Repair operations can be sped up using several approaches. a. In restoration, efforts are made to return a degraded habitat/ecosystem to its natural state. b. In rehabilitation, a degraded ecosystem is turned back into a functional or useful ecosystem without restoring its original condition. c. A degraded ecosystem may be replaced with another type of ecosystem. d. An artificial ecosystem may be created. 2. Even if we are unable to restore an ecosystem to its original condition, man’s destruction must be counterbalanced, and with experience, the effectiveness of ecological restoration will improve. 3. A science-based approach to restoration includes: identify causes of degradation, eliminate/reduce those factors, reintroduce key species, and protect the area from further degradation. D. Reconciliation or applied ecology focuses on inventing, establishing, and maintaining new habitats to conserve species diversity in places where people live, work, or play. E. The Blackfoot Challenge successfully restored and enhanced large areas of wetlands, streams, and native grasslands (See Case Study). 6-5 How Can We Protect and Sustain Marine Biodiversity? We know very little about the earth’s aquatic biodiversity because there has been so little exploration of the water on this “water planet.” A. Three patterns of marine biodiversity are: 1. The greatest marine biodiversity occurs in coral reef and on the deep-sea ocean floor. 2. Biodiversity is higher near the coasts because of great variety of producers, habitats, and nursery areas. 3. Biodiversity is higher in the bottom region of the ocean because of the greater variety of habitats and food sources. B. Threats to marine systems (HIPPCO) 1. Sea-bottom habitats are destroyed by dredging operations and trawling fishing boats. 2. Deliberate or accidental introduction of invasive species. 3. The pressure of coastal development: inputs of sediment and waste, threaten shore-hugging species as well as highly productive coastal ecosystems. 4. Climate change, which causes a rise in sea levels that drown coastal ecosystems. 5. Overfishing, which reduces breeding stock needed for recovery and threatens many fish species with extinction. C. Protecting marine diversity is difficult because of several factors. 1. Difficulty in monitoring the quickly expanding human ecological footprint in aquatic areas. 2. The inability to view damage to the oceans. 3. The belief that the size of the ocean keeps it from being damaged. 4. The lack of international agreements to protect the ocean. D. To sustain marine biodiversity, we must: 1. Protect endangered species. 2. Establish protected sanctuaries. 3. Manage coastal development. 4. Reduce water pollution. 5. Prevent over-fishing. E. To protect marine biodiversity, we must: 1. Establish protected marine sanctuaries, MPAs (marine protected areas). 2. Establish integrated coastal management: identify problems and goals, develop workable and cost-effective solutions 3. Protect existing coastal and inland wetlands from destruction/degradation. 4. Manage marine fisheries to prevent over-fishing. 5. Regulate and prevent aquatic pollution. 6-6 How Should We Protect and Sustain Freshwater Biodiversity? A. Human activities are severely threatening freshwater lakes, rivers, and fisheries. 1. Habitat disruption 2. An increase in the amount of water we withdraw yearly from lakes and rivers 3. Invasion of invasive species (See Case Study: Can the Great Lakes Survive Repeated Invasions by Alien Species) 4. Pollution 5. Climate change B. Understanding watersheds is a key part of recognizing the connection between land and water and protecting both. 6-7 What Should Be Our Priorities for Sustaining Terrestrial and Aquatic Biodiversity? A. Edward O. Wilson’s priorities for protecting the world’s ecosystems and species are: 1. Map the world's land and aquatic biodiversity (identify, locate species) to make conservation efforts precise, cost-effective. 2. Identify and preserve the world's terrestrial and aquatic biodiversity hotspots 3. Cease all logging of old-growth forests everywhere. 4. Create large and fully protected marine reserves to allow damaged marine ecosystems to recover. 5 Protect and restore watersheds 6. Initiate ecological restoration projects worldwide (coral reefs, inland/coastal wetlands) to preserve biodiversity and ecosystem services in these systems. 7. Make conservation efforts beneficial to people who live in/near protected areas Teaching Tips Active Learning: Post-It Note Technique 1. Active learning is becoming increasing popular within the education realm as more and more instructors are using this technique during class time. Often, instructors find that active learning is an effective way to deal with troublesome behaviors that are present within classes predominately based on lecture. 2. Active learning is a great way to get students involved in class material and provide hands-on opportunities to learn, discuss, and share. There are many active learning techniques. One activity that is well-liked and fairly simple to implement is the “Post-It Note” activity. Enough Post-it notes for each student is the only item needed to for this active learning activity. This activity has many variations, but commonly is used to share viewpoints, present solutions, and recall class material. 3. Begin by deciding how many Post-it notes each student will receive. Note that each Post-it note represents the number of contributions that each student will be required to make. Remember, these contributions may be viewpoints on a particular topic, solutions to a problem, or recall of important key concepts. Give students the needed time to write their responses on the Post-it(s). The Post-it(s) are then placed onto each student’s shirt. 4. Next, students should circulate amongst one another reading and discussing the responses. Students are encouraged to swap Post-it’s with other classmates when they learn something new or find another student’s response persuasive. Another option would be to have students get into small groups and share their responses within their group. 5. For example, discussion question number 7 found under the Attitudes & Values section below would work well for this activity. The question asks: What steps do you feel should be taken to support human cultures and wildlife species in ways that create sustainable societies? 6. After sharing their responses with one another, the Post-it notes could then be put on a display board or wall for further classroom discussion. Consider having the class select the five best solutions proposed. Have the class rationalize why they selected what they did. Topics for Term Papers and Discussion Conceptual Topics 1. Multiple-use and moderate-use public lands in the United States. Bureau of Land Management policies and programs in the arid West; the U.S. Forest Service; Gifford Pinchot and the forest conservation movement; sustainable forestry’s answer to clear-cutting; the role of fire in forestry management; the Sagebrush Rebellion. 2. Tropical Rain Forest. Medicinal plants; damage caused by mahogany tree harvesting; biodiversity; ecological functions. 3. A comparison of old-growth and second-growth forests. 4. Restricted-use lands in the United States. The National Parks System; the National Wilderness System. 5. Wilderness preservation in developing countries: success stories (Costa Rica) & challenges (Brazil, Indonesia). Biosphere reserves. Attitudes & Values 1. What wildlife is most common in your area? Where are the nearest locations in your area to go to observe wildlife? What are your feelings toward wildlife species? What relationship between humans and wildlife do you find most desirable? 2. Do you feel that humans have the right to relate to other species in any way they wish? If not, what limits do you see on human behavior toward other species? 3. Do you use products that come from the tropical forest? Do the products you use result in destruction of forest or continued sustainable use of the forest? 4. How do you feel when you see pictures of the destruction of ancient forests? Do you feel we can continue to find substitutes for losses we suffer when ancient forests are destroyed? 5. How do you feel when you see pictures of unemployed loggers unable to support their families? Is it really the spotted owl versus the loggers? 6. Do you feel it is right to destroy cultures that live sustainably in the tropical rain forests? If not, what steps do you support to protect these cultures? 7. What steps do you feel should be taken to support human cultures and wildlife species in ways that create sustainable societies? 8. Have you ever visited rangeland? How did you feel about the land? What benefits do you enjoy as a result of cattle grazing? 9. Have you ever visited a national forest? How did you feel about the forest? What benefits do you enjoy as a result of lumbering activity? Do you feel nature can continue to replenish forests at any rate humans choose to harvest the forests? 10. Have you ever visited a wilderness area? How did you feel about the wilderness? What benefits do you enjoy as a result of protection of wilderness areas? Do you feel more land should be set aside as biosphere reserves? 11. Would you support classifying a much larger proportion of the public lands (such as parks, forests, and rangeland) in your country as wilderness and making such land unavailable for timber cutting, livestock grazing, mining, hunting, fishing, motorized vehicles, or any type of human structure? Why or why not? 12. What is the best way for Madagascar, one of the world’s richest countries in biodiversity, to develop sustainably? 13. What is the value of biodiversity? Should the United States take a global leadership role in protecting biodiversity? Why or why not? 14. Are developed countries exploiting the resources of developing countries? How much tropical forest is a fast-food hamburger worth? 15. What is the trade-off between fuelwood and public health in developing countries? 16. How does a pioneer’s worldview affect human migration and resource consumption patterns? 17. Should fires be allowed to burn in forests on public lands? Should mining be allowed in national wildlife refuges? Should parts of the wilderness areas be set aside for wildlife only? Alaska’s value: wilderness or oil supply? Action-Oriented Topics 1. Individual. Tree planting movements. 2. Groups. The Nature Conservancy; the Wilderness Society; reducing the pressure of people on the national parks. 3. Regional. Sustainable use of tropical forests; rubber tapping in South America; steps that can be taken to resolve the economic problems of logging communities in the Pacific Northwest. 4. National laws. The Alaskan Land-Use Bill; the Endangered American Wilderness Act of 1978; the Wild and Scenic Rivers Act of 1968; the 1974 and 1976 Forest Reserves Management Acts. 5. Global. Rio Earth Summit of 1992. Efforts at a biodiversity treaty. Who is the treaty for? Who isn’t it for? Why? The UN World Heritage Trust; debt-for-nature swaps; solar cookers and the world firewood crisis. Activities and Projects 1. Invite a furniture manufacturer or salesperson to talk to your class about the different types of wood that are available. What are the basic differences in wood quality? Have him or her explain why walnut furniture was the rage in the 50s and 60s but can no longer be bought. Another approach would be to have a program on specialty wood products, such as wood used for musical instruments. 2. One of the useful therapies that help some institutionalized patients could be called nature therapy. Why would taking disturbed patients to natural habitats have a healing effect? 3. Invite a National Park Service or state official to your class to discuss park problems and future management plans. 4. As a class field trip, visit a forest managed for pulp and paper production or industrial timbering. What specific methods are used to maximize economic returns and to curb ecosystem damage? Contrast the appearance of commercial forestland and relatively undisturbed forestland. Which do you like best? Why? 5. Arrange a field trip to a wilderness area. Collect works of art, music, and literature that reflect human feelings toward the wilderness. Hold a class discussion about the value of wilderness areas. 6. Have your students do a survey of the popular magazines and other print media so that they can assess topics such as deforestation, effects of acid deposition of forests, forest decline, the fuelwood crisis, the destruction of giant redwood forests, and the exploitation of a particular species (for example, harvesting Pacific yew trees to obtain Taxol for cancer treatment). 7. Consider the many different ways that the Amazon Basin could be used. Which use would have the greatest impact and which would have the least impact? Why? 8. If there are rangelands in your locale, try to schedule a class visit to examples of well-managed and poorly-managed grazing lands. Compare the quantity and quality of vegetation present. BBC News Videos The Brooks/Cole Environmental Science Video Library with Workbook, Featuring BBC Motion Gallery Video Clips, 2011. DVD ISBN: 978-0-538-73355-7 (Prepared by David Perault) Darwin's Galapagos Under Threat Suggested Answers for Critical Thinking Questions 1. Concept 6-6 proposes that sustaining freshwater biodiversity involves protecting watersheds, preserving wetlands, and restoring degraded freshwater systems. Student answers will vary but may include participating in creek/coastal clean-up projects (and even continuing them year-round!), being politically active to promote wetland preservation and habitat restoration, participating in restoration projects (such as removing invasive species, planting native species, etc.), community projects related to minimizing runoff from residential/commercial sources, patronizing businesses who are water-friendly (water use, waste management, pollution prevention, etc.) 2. Student answers will vary. Some alternatives to cutting trees that would provide biofuels include growing oil palm trees in already deforested and degraded land and investing more energy into sources such as corn-ethanol biofuel, which can be grown in already agriculturally developed land. Other biofuel options include switchgrass, ryegrass, and other non-food plants (“Grassohol”) 3. Student answers will vary but may argue, for example: Yes, developed countries should provide most of the money for efforts to preserve remaining tropical forests in developing countries. Developed countries have a much larger ecological footprint than developing countries. The tropical forests are an enormous provider of ecological services such as storing atmospheric carbon and purifying air and water. If developed countries take financial responsibility to preserve the forests, they can counteract some of their pollution emissions and wasted resources. No, developed countries should not have to provide most of the money because preserving tropical forests benefits the entire planet. All countries should share the responsibility. It can even be argued that since the tropical forests are located within developing countries where most of the unsustainable cutting and burning is actually occurring, the financial responsibility should rest with those countries. 4. Students who support the reintroduction of the grey wolf may discuss the overall success of the program in the Yellowstone ecosystem. Opinion regarding the reintroduction of the wolves to areas outside of the park will vary, but should consider habitat impacts as well as carrying capacity of the area under consideration, and opposing views held by ranchers and other people living and working in the area. Opinions about reintroduction of bears maybe different than those related to reintroduction of wolves, since the threat to humans seems greater. 5. Answers will vary depending on where students live (or grew up). Examples of three human activities on land affecting a body of water are: i) Withdrawing water from rivers and lakes for agricultural irrigation with possible pollution from fertilizers and pesticides in run-off water. ii) Unsustainable cutting and burning of forests. iii) Untreated sewage and litter may find their way to water bodies. Lifestyle changes to lessen the impact on water systems include: using less water (often by wasting less water) in household activities (washing, bathing, toilet flushing, fixing leaks, etc.), reducing pollution by not washing car in driveway, picking up litter that may blow into water; eating sustainably produced food, using recycled products. 6. Student answers will vary, but their “policies” should reflect the priorities and trade-offs associated with conservation/preservation and pollution-prevention of each ecosystem described. Socio-economic, political, business, individual and environmental concerns should all be addressed in formation of policies. Emphasis should be placed on individuals, businesses, communities where appropriate. General approaches of pollution-prevention, wilderness protection, habitat restoration, and minimizing/repairing human impacts are expected. Instructor Manual for Sustaining the Earth G. Tyler Miller, Scott E. Spoolman 9781285769493