1 / 25

Chapter 10 Biodiversity

Chapter 10 Biodiversity. Biodiversity – the variety of living things in an area; three levels: 1. 2. 3. Benefits of Biodiversity. Biodiversity can affect the stability of ecosystems When even one species is lost, it affects the entire ecosystem.

illias
Download Presentation

Chapter 10 Biodiversity

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Chapter 10 Biodiversity

  2. Biodiversity – the variety of living things in an area; three levels: 1. 2. 3.

  3. Benefits of Biodiversity • Biodiversity can affect the stability of ecosystems When even one species is lost, it affects the entire ecosystem

  4. Keystone species – species that are critical to the survival of an entire ecosystem Example: sea otter, p. 242

  5. Healthy ecosystems provide good ecosystem services – the benefits that people obtain from ecosystems See list on p. 357

  6. Ecosystem Services: the benefits people obtain from ecosystems Regulating Benefits obtained from regulation of ecosystem processes • climate regulation • disease regulation • flood regulation Provisioning Goods produced or provided by ecosystems • food • fresh water • fuel wood • genetic resources Cultural Non-material benefits from ecosystems • spiritual • recreational • aesthetic • inspirational • educational Supporting Services necessary for production of other ecosystem services • Soil formation • Nutrient cycling • Primary production

  7. Benefits of Biodiversity 2. Biodiversity can affect the sustainability of populations • Need for genetic diversity – increases the chance that some members of a population will survive change • “Living dead” – species that has reached the point where no amount of intervention can save it

  8. Humans need biodiversity for medical, industrial, and agricultural purposes See Table 1 on p. 243.

  9. Potential new food crops may be lost forever Source: FAO

  10. Ethics, aesthetics, and recreation E.O. Wilson: there is “spiritual, religious and psychological value” in preserving biodiversity Ecotourism – tourism that supports conservation and sustainable development of ecologically unique areas

  11. Biodiversity at Risk Extinction is a natural process Mass extinction – when more than half the existing species go extinct over a period of 1000’s or tens of thousands of years Are we heading for a sixth mass extinction? Predicted time to completion: 100 years Cause: human activity

  12. Endangered species – a species that is likely to become extinct unless some protective measures are enacted immediately Threatened species – species with declining populations, likely to become endangered if not protected

  13. How do humans cause extinction? 1. Habitat destruction – may be complete destruction or habitat fragmentation

  14. Introduction of invasive species Example: Mites, called Verroa destructor, introduced from Asia have reduced the wild honeybee population in the U.S. to 2% of what it used to be

  15. Harvesting, hunting, poaching Both legal and illegal collecting of organisms has had a negative impact

  16. Pollution Example: Use of DDT almost caused the extinction of the Bald Eagle and other predatory birds, see p. 120-121

  17. How do humans cause extinction? Species Introductions 39% Hunting 23% Other 2% Habitat Destruction 36%

  18. Areas of Critical Biodiversity • Tropical rainforests • Coral reefs and coastal ecosystems • Islands • Biodiversity “hotspots” • High numbers of endemic species • Threatened by human activities • Examples: see p. 250

  19. Efforts to Preserve Biodiversity • Efforts to save individual species • Captive-breeding programs – California condor population went from 9 in 1986 to 58 in 2002 • Zoos, aquariums, parks, gardens – for many, there is now more emphasis on preservation and less on entertainment

  20. Efforts to save habitats and ecosystems It is important to save the entire ecosystem, not just an isolated species Example: Vermillion Darter The vermilion darter is found only in the Turkey Creek drainage, a tributary of the Locust Fork of the Black Warrior River, Jefferson County, Alabama. The current range of the vermilion darter is about seven miles in the Turkey Creek system. Surveys conducted in 2003 indicated that the vermilion darter has declined substantially in this drainage. The greatest threat to the vermilion darter is water quality and substrate degradation caused by sedimentation and other pollutants.

  21. Legal protection – exists in many countries U.S. has Endangered Species Act, passed in 1973 Main Provisions (p. 255): U.S. Fish and Wildlife Service (USFWS) complies a list of endangered and threatened species on land and in freshwater, National Marine Fisheries Service is responsible for marine species End./Thr. Species may not be killed, caught, sold (penalties include fines and jail, enforced mainly by USFWS, also Coast Guard) Fed. Govt. may not carry out projects that jeopardize listed species USFWS must develop a recovery plan for each listed species

  22. Successful recoveries • Species which increased in population size since being placed on the endangered list include: • Bald Eagle (increased from 417 to 11,040 pairs between 1963 and 2007); removed from list 2007 • Whooping Crane (increased from 54 to 436 birds between 1967 and 2003) • Kirtland's Warbler (increased from 210 to 1,415 pairs between 1971 and 2005) • Peregrine Falcon (increased from 324 to 1,700 pairs between 1975 and 2000); removed from list • Gray Wolf (populations increased dramatically in the Northern Rockies, Southwest, and Great Lakes) • Gray Whale (increased from 13,095 to 26,635 whales between 1968 and 1998); removed from list • Grizzly bear (increased from about 271 to over 580 bears in the Yellowstone area between 1975 and 2005); removed from list 3/22/07 • California’s Southern Sea Otter (increased from 1,789 in 1976 to 2,735 in 2005) • San Clemente Indian Paintbrush (increased from 500 plants in 1979 to more than 3,500 in 1997) • Red Wolf (increased from 17 in 1980 to 257 in 2003) • Florida's Key Deer (increased from 200 in 1971 to 750 in 2001) • Hawaiian Goose (increased from 400 birds in 1980 to 1,275 in 2003) • (increased from 3,500 in 1979 to 18,442 in 2004)

  23. International efforts IUCN – organization that publishes the “red list” of endangered species, promotes preservation of species and habitats CITES treaty – first effort to stop killing of African elephants for ivory tusks Biodiversity Treaty – came out of Earth Summit, 1992, controversial

  24. Private organizations Examples: World Wildlife Fund, Nature Conservancy, Greenpeace International

More Related