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BIOLOGY PROJECT BIODIVERSITY* Biodiversity: is the variation of life forms within a given ecosystem, biome, or for the entire Earth. • genetic • species • ecosystem BIODIVERSITY BENEFITS* Human uses 1.FOOD RESOURCES 2. Drugs 3.Raw materials for manufacturing Fibres WAXES pesticides lubricants perfumes 4. Rapidly growing leisure industry Eco-tourism which is based on the observation of wild animals and wilderness habitats generates billions US dollars profit annually. Non-Human use • • • • • nutrient cycling soil formation watershed protection waste disposal Pollination • • • oxygen production carbon dioxide absorption climate regulation However, we humans are facing serious threats to the survival of biodiversity. Increasing numbers of species disappearing every day. Extinction of different kinds of organisms has been much greater than before. A variety of human activities are the main causes. Current rates of extinctions are alarmingly high. The extinction rate for birds and mammals was about 1 species every decade from 1600 to 1700. But, it rose 4 species every year between 1986 and 1990. Apparently, the rate of extinction is accelerating. CAUSES* 1.Habitat degradation (1) destruction (2) pollution e.g. pesticides, sewages, combustions (3) human disruption e.g. mining for fossil fuels (4) habitat fragmentation (diving up the habitat into small isolated areas) (5) over-hunting Rapid human population growth (1)Demand on food destruction of habitat of animal for cultivation remove various species of plant of that habitat cultivate single species of plant cannot maintain the gene pool (2)Demand on places deforestation / logging commercial building, building up the societies. supply furniture have to kill or expel animals Cultivation for food farming African elephants lost a large piece of land Number of African elephant decrease fall to the edge of extinction p.s. Overexploitation for elephants’ tusk (ivory) Global warming climate change melting of ice in polar Polar bears cannot find floating ice in Arctic Ocean 2.Species overexploitation Species that are hunted or harvested by humans. There are many examples of overexploitation: (1)passenger pigeons (2)bison (3)sharks e.g. fins (4)commercial fish such as Atlantic bluefin tuna (5)coral fishes e.g. Humphead wrasse(蘇眉). (6)lion,fox,raccoon e.g. fur (7)elephant e.g. Craft work: Ivory tusk 3.Introduced species The introduction of exotic species is a potent threat to biodiversity. the endemic species in that ecosystem that have not evolved to cope with the exotic species became the prey of the exotic ones. E.g. African bees, Dodo bird CONSEQUENCE* Threatens the economy The depletion of fish stocks from overfishing and illegal fishing to agricultural activities polluting river basins Economy is directly dependent on natural resources for their livelihoods Affecting the life support Collapse of ecosystem -Food web is affected -The keystone species may be removed -Greater competition and predation SOLUTION* Policy level -Banning of Over-exploitation -The bodies such as the International Whaling Commission and the Convention on International Trade in Endangered Species (CITES). Conservation -Green lobbies and Government -conservation of endanger organisms -116 species of European farmland birds are now of conservation concern Green lobbies and Government Sustainable development -unprecedented collective effort is needed to return human use of natural resources to within sustainable limits -maintaining a certain process of ecosystems and biodiversity -A long-sighted policy which is benefic for our offspring and also the environment -resources must be used at a rate at which they can be replenished -maintain the gene pool continuously E.g. eco-municipalities, sustainable cities Smart growth -An urban planning and transportation theory that concentrates growth in the center of a city to avoid urban sprawl E.g.(1)neighborhood schools (2)complete streets (3)mixed-use development (4)regional considerations of sustainability Our response as individuals -Change our Lifestyle -E.g. Don’t use the wood from sustainable forestry and recycle our news-paper and don’t use the toxic chemicals which are harmful to wildlife in our home -Caring for the living world around us -being volunteers and supporting the conservation organizations or green lobbies