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BIODIVERSITY and CONSERVATION http://darwin.bio.uci.edu/~sustain/bio65/ (OR – search for Biodiversity Conservation UCI).
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BIODIVERSITY and CONSERVATIONhttp://darwin.bio.uci.edu/~sustain/bio65/(OR – search for Biodiversity Conservation UCI) The origin, evolution, and value of biological diversity. Extinction and depletion caused by overexploitation, habitat loss, and pollution. Conservation through habitat preservation and restoration, captive breeding, and reintroduction. 30%~50% Writing Assignment 30% Mid-term 40% Final Slide shows and other protected pages: User ID = Bio65; password = students
Three assignments • Write a letter. Deadline: First mid-term • Learn about local biodiversity. Deadline: Second Midterm • Help with a local habitat restoration project. Deadline: Final Exam
Biodiversity: • All living things • Conservation: • Preventing loss • Arguments: • Anthropocentric • Biocentric • Local Data: • Natural History of Orange County, California Recommended reading: Wilson, E. O. (2002) "The Future of Life". Alfred A. Knopf, publisher.
A typical day on planet Earth • We will lose forest the size of New York City • We will lose 40 to 100 species • We will add 250,000 people • We will add 2,700 tons of chlorofluorocarbons to the atmosphere • We will add 15 million tons of carbon to the atmosphere
Human domination of Earth: 1. Land surface • We have reduced forests from roughly 50% of the earth's land surface to less than 20%. • If deforestation continues at present rates, Thailand will have no forest left in 25 years; the Philippines in less than 20 years, and Nepal in 15 years. • Many of the large areas of grassland in the world were originally forest and were created by deforestation. • Many of the dry deserts of North Africa, Greece, Italy, and Australia were created by deforestation followed by soil erosion • The Earth's land masses lose ~ 24 billion tons of topsoil every year
Human domination of Earth: 2. Atmosphere • Atmospheric CO2 increased by 30% • Global average surface temperature increased by >1ºC • These are probably related! Source: Millennium Ecosystem Assessment
Since 1979, the size of the summer polar ice cap has shrunk more than 20 percent. (Illustration from NASA)
According to the IPCC, North Pole sea-ice has thinned by 40% in recent decades.
Rising temperatures are thought to cause sea levels to rise as the oceans expand and polar ice melts. The IPCC says sea levels rose between 10 and 20cm worldwide during the 20th Century. It predicts a further rise of between 9cm and 88cm by 2100.
Disappearing Glaciers Upsala Glacier, Argentina Riggs Glacier, Alaska The Global Retreat of Glaciers Shrinking Glaciers Thawed Faster in 2005 Rhone Glacier, Switzerland
Wrapping Glaciers The thin protective layer of foil covers an area of 3,000 sq m Wrapping the Gurschen glacier
“ there have been more than four times as many weather-related disasters in the last 30 years than in the previous 75 years. The United States has experienced more of those disasters than any other country. (May 2008): a swarm of tornadoes shredded the central states. California and Florida have been scorched by wildfires, and a crippling drought in the Southeast has forced Georgia to authorize plans for new reservoirs.” http://www.nytimes.com/2008/05/31/opinion/31blow.html?th&emc=th
Climate Change: 2006 data • The sixth warmest year since record-keeping began in 1880 (2005 was warmest) • Arctic sea ice in September was at 5.9 million sq. km., the second lowest on record. • Canada: mildest winter and spring on record • U.S.: warmest January-September on record. • Australia: warmest Spring since record-keeping started in 1950 • Severe droughts in some areas (China, Brazil, parts of Africa, Australia, parts of U.S.) • Severe flooding elsewhere (parts of Africa, U.S.) • Record numbers of hurricanes in the Pacific, cyclones in China and Australian regions • In September, the ozone hole over the Antarctic was the largest ever http://www.ens-newswire.com/ens/jan2007/2007-01-03-02.asp
Biological Indicators (of 116) • 26. Washington, D.C. -- Cherry trees blossoming earlier. Average peak bloom from 1970-1999 came April 3, compared to April 5 from 1921-1970. • 28. California -- Butterfly range shift. Edith's Checkerspot Butterfly has been disappearing from the lower elevations and southern limits of its range. • 31. Olympic Mountains, Washington -- Forest invasion of alpine meadow. Sub-alpine forest has invaded higher-elevation alpine meadows, partly in response to warmer temperatures. • 33. Alaska -- Sea bird population decline. The black guillemot population is declining from 1990 levels because melting sea ice has increased the distance the birds must fly to forage for food and reduced the number of resting sites available. • 34. Canadian Arctic -- Caribou die-offs. Peary caribou have declined from 24,000 in 1961 to ~ 1,100 in 1997, mostly because of major die-offs after heavy snowfalls and freezing rain that covered the animals' food supply. • 35. Monterey Bay , California -- Shoreline sea life shifting northwards.
Human domination of Earth: 3. Freshwater Ecosystems • We usemore than halfof the accessible surface fresh water • Water withdrawals from lakes and rivers has doubled in the last 40 years. • Flow from rivers has been reduced dramatically. • For parts of the year, the Yellow River in China, the Nile in Africa and the Colorado in N. America dry up before they reach the ocean • 69 dams have been built on the Columbia River • Many of the rivers in industrial areas (e.g. Rhine, Danube, Illinois, Cuyahoga, Mississippi) are so polluted and low in oxygen that very few species can live in them any more. • Thousands of lakes in N. America have been sterilized by acid rain Source: Millennium Ecosystem Assessment
Lake Victoria, the world's largest tropical lake and the second largest freshwater lake, is dying • Introduction of Nile Perch led to the extinction of at least 200 species of endemic cichlids ("the greatest vertebrate mass extinction in recorded history”) • Nile Perch now makes up 80% of fish biomass in the lake. • Fish filets are exported to Europe and Russia; the locals get the left-overs (Film: “Darwin’s Nightmare”). • Loss of the cichlids, plus massive nutrient pollution from agriculture, industrial and sewage pollution has led to overgrowth of algae and the appearance of huge dead zones with low oxygen. • The lake has also been invaded by water hyacinth which deprives other lake vegetation of sunlight and further depletes oxygen
Human domination of Earth: 4. Oceans • Since 1980 • ~35% of mangroves have been lost • ~20% of coral reefs have been destroyed and another 20% badly degraded. • Many coastal areas suffer eutrophication and toxic algal blooms caused by nutrient runoff. • Dead zones becoming more numerous • Plastic pollution now found in the entire water column • Noise pollution from low-frequency active sonar is confusing and probably causing ear damage in marine mammals
Human domination of Earth: 5. Species Introductions • On many islands, > half of plant species have been introduced by man; on continental areas the fraction is 20% or more. • > 4,000 exotic plant and 2,300 exotic animal species are now established in the U.S. • The Baltic Sea is now home to ~100 introduced species, a third of them native to the Great Lakes of N. America. • The Great Lakes are now home to ~170 introduced species, a third of them originally from the Baltic. • Introduction of the American comb jellyfish in the Black Sea led to the destruction of 26 commercially important stocks of fish. • In San Francisco Bay, >half of the species are exotic.
Human domination of Earth: 6. Species Extinction • Prehistoric: After primitive humans arrived in America, Europe and Australia, the megafauna soon disappeared: all the large herbivores (mammoths, mastodons, ground sloths, cave bears, woolly rhinoceros, other rhinoceroses, etc.) and the carnivores that fed on them, the dire wolves and saber-tooth cats. • Historic: documented extinctions: • Birds: 42 species and 44 subspecies • Mammals: 73 species and 30 subspecies • Amphibians: 122 species • Current: Species threatened with extinction this century: • 25% mammals, 25% amphibians, 11% birds, 20% reptiles, 34% fish, 10% trees
Human domination of Earth: 7. Depletion of terrestrial species by Overharvesting • Most targets of the fur, leather, ivory and medicine trades reduced to small fractions of their original populations. Some also threatened by habitat loss: • squirrels, martens, ermine, sable, foxes, beaver, otter, sea otter, pine marten, fisher, wolverine, buffalo, fur seal, harp seal, cheetah, tigers, many other cats, chinchilla, vicuna, giant otter, many primates, pandas, elephants, rhinos • Several valuable tree species, including West Indian mahogany, Caoba mahogany of Ecuador, and Lebanese cedar, have been reduced to a few scattered ruins of forest. • Many orchids, tropical fish and birds have been threatened by overhunting for the pet trade.
Human domination of Earth: 8. Depletion of Marine Species by Overharvesting • Many marine mammals severely depleted due to overharvesting for oil, meat, ivory: Walrus, elephant seal, sperm, bowhead, right, humpback, blue, fin, sei whales, Dall’s porpoise • Many major marine fisheries have collapsed: e.g. California sardine, Atlantic Cod, Pacific Cod, Hake, Pollack • In some areas, the catch is now <1% of that before industrial fishing • Many invertebrate fisheries have also collapsed: e.g. abalone, blue crabs, oysters • Pacific salmon harvest down to about 10% of historical • The total weight of the ocean's large predators - tuna, swordfish and sharks – is down to 10% of historic Atlantic Cod, E. coast of Newfoundland
Predicted Total Loss of Commercial Seafood • In 2003, 29% of commercial fisheries had collapsed • Extrapolation: All commercial fish and seafood species will COLLAPSE by 2048 Trajectories of collapsed fish and invertebrate taxa over the past 50 years (diamonds, collapses by year; triangles, cumulative collapses). Data are shown for all (black), species-poor (<500 species, blue), and species-rich (>500 species, red) LMEs. Global Loss of Biodiversity Harming Ocean’s Bounty Impacts of Biodiversity Loss on Ocean Ecosystem Services
Human domination of Earth: 9. Secondary and Indirect Effects of Overharvesting • Driftnet fishing for squid and swordfish kills thousands of salmon, dolphins, whales, seabirds, and seals • Many dolphins killed in tuna fishery • Sea turtle and fish killed in the shrimp fishery • Massive damage to sea floor by bottom trawling • Ecosystem collapse: • Aleutian Islands • Kelp Forests in Pacific and Atlantic • Chesapeake Bay Oyster Beds
The Millennium Ecosystem Assessment2005; more reports being releasedCommissioned by the UN – a 4-year effort by 1,300 scientists from 95 countries. Most comprehensive survey into the state of the planet - concludes that human activities threaten the Earth's ability to sustain future generations. Defines ecosystems in terms of the "services", or benefits, that people get from them – wood for building; clean air to breathe; fish for food; fibers to make clothes.(An “Anthropocentric” view)
The Millennium Ecosystem Assessment- Conclusions • By 2050, the planet's population will increase from 6 to 9 billion, with most people migrating to massive cities. • The global economy will quadruple. • Demand for food, fresh water and raw materials for construction and heat will stretch natural resourcesto their limits • If major changes are not made in the way humans consume natural resources, • there will be widespread famine, • severe shortages of clean water • huge impacts from natural disasters such as hurricanes. • Cities will be beset by vast amounts of wastewater and sewage. • Sea levels will rise • Fisheries will collapse • Emerging disease epidemics will sweep across the globe • Coral reefs will die off (ALL of these are already happening!)
What you can do! Write letters
Writing assignment:Write and send three letters • Local issue • State issue • National or international issue • (Links to instructions and tips in Chapter 1) • Each with a one-page background report • Conservation Issue Guides • Letter, copy of letter, report and stamped addressed envelope to me in time for both deadlines • My deadlines: listed on syllabus • Agency deadlines (listed on issue guides) • No credit for late letters! • http://darwin.bio.uci.edu/~sustain/bio65/