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BIODIVERSITY Refers to the broadly diverse forms in which organisms have evolved and is considered at three levels: 1. Genetic diversity: variation in genes enabling organisms to evolve and adapt to new conditions; 2. Species diversity: the number kind and distribution of species within an ecosystem; 3. Ecosystem diversity: the variety of habitats and communities of different species that interact in a complex web of interdependent relationships. 1 THREATS TO BIODIVERSITY "Virtually all students of the extinction process agree that biological diversity is in the midst of its sixth great crisis, this time precipitated entirely by Man." -- E.O. Wilson Harvard University Currently, more than 10,000 species become extinct each year Rate has increased alarmingly in recent years. The central cause of species extinction is destruction of natural habitats by human beings. o Habitat destruction (burning or felling of oldgrowth forests) o Overexploitation (over hunting of elephants and rhinos) o Pollution (industrial emissions that cause acid rain) o Global climate change (the greenhouse effect and destruction of the ozone layer) o Invasion by introduced species (displacement of native songbirds in the U.S. by European starlings) 2 Threats driven by underlying social conditions o Increased per-capita consumption o Poverty o Rapid population growth o Unsound economic and social policies. VALUE OF BIODIVERSITY Human survival may depend upon reversing this accelerating threat to species diversity. Among the millions of undescribed species are important new sources of food, medicine When a species vanishes, we lose access to the survival strategies encoded in its genes through millions of years of evolution. We lose the opportunity to understand those strategies, which may hold absolutely essential options for our own future survival as a species. We lose emotionally; we lose the unique beauty, and the unique spirit, associated with that life form. 3 Many indigenous human cultures have also been driven to extinction by the same forces, which have destroyed and continue to threaten nonhuman species. Since 1900 more than 90 tribes of aboriginal peoples have gone extinct in the Amazon Basin. Nearly every habitat on earth is at risk: Rainforests and coral reefs of the tropics, Salt marshes and estuaries of our coastal regions, Tundra of the circumpolar north, Deserts of Asia and Australia, Temperate forests of North America and Europe, Savannahs of Africa and South America. 4 TROPICAL RAINFORESTS Among the most diverse of all terrestrial ecosystems Covering only 7% of the planet's surface, these forests comprise 50-80% of the world's species. 40 million to 50 million acres of tropical forest vanish each year About 1.5 acres per second Trees for lumber Land cleared for agriculture or other development. SOLUTIONS A quarter of the Earth's total biological diversity is threatened with extinction within 20 to 30 years. Solution lies in increased educational efforts. Develop sustainable resources. Rich and poor nations must strive for cooperative stewardship of global biodiversity. 5 WHY SHOULD WE CARE ABOUT BIODIVERSITY? Biodiversity is a necessity, not a luxury. A one-acre patch of elm trees produces oxygen, removes carbon from the atmosphere, and captures at least 16 tons of airborne dirt, which rain then washes back to the ground as productive soil. Provides direct benefits like food, medicine, and energy; Affords us a "life support system." Required for the recycling of essential elements, such as carbon, oxygen, and nitrogen. Responsible for mitigating pollution, Protecting watersheds, Combating soil erosion. Buffer against excessive variations in weather and climate Protects us from catastrophic events beyond human control. 6 Biodiversity is important to the global economy. Modern agriculture, depends on new genetic stock from natural ecological systems, $3 trillion global business; Nature tourism generates some $12 billion worldwide in annual revenues. United States: economic benefits from wild plants and animals make 4.5% of the Gross Domestic Product. 1988: Worldwide commercial trade in wild plants (excluding timber) and animals valued at $5 billion. 20 best-selling US drugs revenues of $6 billion worldwide, All relied on plants, microbes, and animals for development. Each wild plant that provides chemical basis for new drugs generates at least $290 million annually 7 Biodiversity is essential for ensuring food security. Major food crops, corn, wheat, and soybeans, depend on genetic material to remain productive and healthy. Breeders and farmers rely on genetic diversity of crops and livestock to increase yields and respond to environmental changes. Plant breeding, wild genetic stock and other sources, account for half the gains in agricultural yields in United States from 1930 to 1980. Earth's oceans, lakes, and rivers contain food resources. Food production from wild stocks of fish single largest source of animal protein for expanding population. In 1994, more than 10 billion pounds of fish, valued at about $4 billion, caught and sold in the United States alone. 8 Teosinte, A wild relative of corn discovered in Mexico during the 1960s, resists four of the eight major diseases that kill corn in the United States. Had it been available to U.S. farmers in the 1970s, losses of $1 billion could have been avoided when disease wiped out uniformly susceptible varieties. Thanks to Teosinte, prices for grain-fed meats, soft drinks, and other corn-related foods have been kept low. Genetic biodiversity protects American farmers and consumers alike. 9 Biodiversity safeguards human health. 79% of top-selling 150 prescription drugs in US originate in nature. Many synthetic drugs, including aspirin, first discovered in wild plants and animals. Roughly 119 pure chemical substances extracted from 90 species of higher plants used in pharmaceuticals. Traditional medicine: Relies on species of wild and cultivated plants, Basis of primary health care for 80% of people in developing countries. U.S. imports more than $20 million of rain forest plants per year for medicinal properties. Only 2% of the 250,000 described species of vascular plants screened for chemical compounds. Taxol, new drug from the Pacific yew tree, o Used to treat ovarian cancer. o In 1960, a child with leukemia had a 1 in 5 chance of remission. Anti-cancer drugs developed from wild periwinkle - chance of survival 80% 10 Biodiversity provides recreational opportunities. Provides recreational opportunities & aesthetic value. In 1991, recreation associated with wild birds generated nearly $20 million and 250,000 jobs in the United States, Exceeded many Fortune 500 companies. Saltwater recreational fishing in the U.S. generates more than $15 billion annually Provides over 200,000 full-time jobs U.S. parks brought in $3.2 billion from visitors in 1986. Tourism in Kenya amounted to $400 million. The economic value of viewing elephants alone totaled $25 million in 1989. Large economic revenues reflect the high value people place on recreation involving biodiversity. 11 Biodiversity and the issues that affect it cross all national borders. Air and water pollution do not respect national borders Acid rain, air pollutants mix with falling rain, In North America, industrial emissions cause acid rain Sugar maples in Canada, threatens future maple syrup production. Global climate change most serious threat to life Carbon released from human-induced activities Burning of fossil fuels, forests, and other natural habitats Tropical forest burning accounted for 25% of all carbon released into the atmosphere over the past decade. Build-up of carbon dioxide, greenhouse gases, ozone depletion causing climate change. 12 Catastrophic consequences for wildlife and ecosystems Warmer temperatures cause shifting of agricultural lands hundreds of miles north Cause severe coastal flooding. Species migrate to keep up with optimum conditions, Rate of change would be too fast for many to adapt. Loss of biodiversity can even threaten national security. Many national and international conflicts over water, land, and other natural resources. Environmental conflicts lead to mass migrations of people Strain national budgets, public infrastructure, and international relations 13 Rates of species extinction are unprecedented. Virtually all of the loss is caused by human activities, Mostly through habitat destruction and over hunting. Over 34,000 plant species and 5,200 animal species around the globe are threatened with extinction North America: 98% of virgin forests have been destroyed, 54% of wetlands have been lost Over the past 500 years 200 species of plants 71 species & sub-species vertebrates Extinct in North America alone Another 750 species endangered or threatened. 14 Only 13% of the approximately 14 million species on Earth described by scientists. Human pressure on biological resources, increase rates of extinction The undersea kelp forest ecosystems Northern Pacific rim the richest marine habitats known Home or breeding ground of many species of fish and sea otters. Sea otter: western coast of Canada and US Hunted almost to extinction 19th and 20th Century Invertebrates - the sea urchin - left without major predator. Sea urchins increased dramatically; consumed the kelp and other seaweeds Became a barren undersea terrain. Conservation efforts throughout the latter half of the 20th century protected and reintroduction of sea otter to ecosystems; Kelp forests once again thrive. 15 What is being done to conserve biodiversity? 1993 public opinion poll, 89% of the public agrees that human beings have an ethical responsibility for protecting plant and animal species. 78% believe greater protection for fish and wildlife habitats on federal forest lands Public concern benefits society indirectly 1972: public outcry over the declining populations of the American bald eagle The U.S. banned the production and sale of the pesticide DDT This chemical was later identified as a serious cancer-causing agent in humans. Global: International Convention on Biodiversity. Recognizes conservation of biodiversity as global issue More than 100 countries have ratified it. 16 What can we do? Individuals: Conserve biodiversity by Investing in and supporting environmentally sound businesses; o Supporting local, national, and international conservation efforts; o Minimizing our consumption of gasoline, electricity, and material goods; o Becoming informed about legislation that affects the world's biodiversity and sharing our concerns with our elected representatives. Society o Curb our use of energy, o Eliminate our consumption and use of threatened species, o Support the transformation of national and international policies to those that are more sustainable and less harmful to biodiversity. 17