Unformatted text preview: Bio Pl 2400 Bio Pl 2400 Part III Biodiversity Loss of Biodiversity Loss of Biodiversity Global Extinction Rate is estimated to be 10 10,000 times higher than it was before human existence. 2200 species/day become extinct 34% of Fish species, 25% of amphibians, 24% of mammals, 20% of reptiles, 14% of plant species face premature extinction In the USA 33% of plant and animal species are vulnerable to extinction Polar Bears Brown Bears Orchid Species Native to USA Pitcher Plant native to Southern USA Human Factors Relating to Human Factors Relating to Decreased Biodiversity Habitat Loss and Degradation Invasive Species Hunting, poaching, overfishing Sale of Exotic Species (animal and plants) Pollution Climate Change Effect of Human Activity on Effect of Human Activity on Biodiversity 4050% of the Earth’s surface has been taken over, disturbed or degraded conversion of forests and grasslands to crop fields or urban areas, filling in wetlands Global forest cover has been reduced by 20 50% Half of all wetlands have been lost in the last century Amazon Rainforest cleared For Agriculture Satellite Image of forest destruction in Bolivia for soybean cultivation United States United States 9595% of virgin forests in the USA have been cleared since 1620 98% of tallgrass prairie cleared in the midwest USA 99% of grassland, 91% of wetlands, 85% of Redwood forests in California are Gone Clear cut forest in Oregon Human Factors Relating to Human Factors Relating to Decreased Biodiversity Habitat Loss and Degradation Invasive Species Hunting, poaching, overfishing Sale of Exotic Species (animal and plants) Pollution Climate Change Invasive Species Purple Loosestrife An invasive species in wetlands Spotted Knapweed An invasive species Zebra Mussel Invasive Species Invasive Species Northern Snakehead Human Factors Relating to Human Factors Relating to Decreased Biodiversity Habitat Loss and Degradation Invasive Species Sale of Exotic Species (animal and plants) Pollution Climate Change Hunting, poaching, overfishing Passenger Pigeon Passenger Pigeon Passenger Pigeon Population estimated to be as high as 5 billion birds in the early 1800’s Hunting became popular in the 1850’s, advanced with the development of the telegraph and railroads in the 1870’s Population down to a few thousand by the 1880’s, last known wild pigeon killed in 1900, last pigeon in captivity died in 1914. Value of Biodiversity Value of Biodiversity
Instrumental value Human centered Utilitarian Uses/ Non Utilitarian Uses Intrinsic Value Inherent Value unrelated to humans Utilitarian Uses Utilitarian Uses Economic GoodsFood, Fuel, fiber, lumber , medicines, etc. 90% of food crops were domesticated wild tropical plants 40% of all medicines, 80% of the top 150 prescription drugs in the USA derived from living organisms. 74% from tropical plants from developing countries 85% of antibiotics are fungal derivatives, 0nly 2% of known fungi have been evaluated. Only 3% of plant species have been examined for useful drugs Digitalis purpureaCommon foxglove Colchicum autumnaleautumn crocus Produces colchicine- an antitumor drug Taxus previfoliaPacific Yew Produces Taxol- antitumor drug Ephedra viridis- Mormon Tea Source of pseudoephedrine Southern Gastric Brooding Frog Utilitarian Uses Utilitarian Uses Ecological Services The flow and cycling of materials and energy in the biosphere Photosynthesis Pollination of crops aand other plants Soil formation and maintenance Nutrient Recycling Absorption and detoxification of pollutants in air and water Utilitarian Uses Utilitarian Uses Information Genetic information and educational or scientific information from studies Recreation Ecotourism Americans spend 3 times more to watch wildlife than movies or professional sports A male lion living to age 7 in Kenya generates $515,000 in tourism revenue, $1,000 if killed for its hide. NonUtiliitarian Uses NonUtiliitarian Uses We find value in its existence, aesthetic beauty Intrinsic Value of Biodiversity Each Species has an inherent value and right to exist ...
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This note was uploaded on 01/26/2009 for the course BIOPL 2400 taught by Professor Silva,t. during the Fall '08 term at Cornell.
- Fall '08