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Biodiversity

Biodiversity. Its Importance and Its Future. Biodiversity. Biodiversity. The number and variety of different species in a given area Humans need to preserve biodiversity for our own survival Extinction of species leads to a decrease in biodiversity

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Biodiversity

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  1. Biodiversity Its Importance and Its Future

  2. Biodiversity

  3. Biodiversity • The number and variety of different species in a given area • Humans need to preserve biodiversity for our own survival • Extinction of species leads to a decrease in biodiversity • Humans don’t know which species are key to our survival on Mother earth

  4. Benefits of Biodiversity • Species and ecosystems are interconnected • Species and populations must survive • Humans are dependent on species for medical, industrial, and agricultural uses • The are ethical, aesthetic and recreational reasons to preserve species, ecotourism

  5. Benefits of Biodiversity • Keystone species: any species that must be present in a ecosystem for that ecosystem to survive • When a species is removed, a strand of a food web is eliminated

  6. Species versus populations • In general, in any given area, the more species, the smaller the population • And the less species, the larger the population • Always remember that an ecosystem is healthiest when there are the gretest number of species • When an ecosystem is healthy, it is less likely for any individual species to go extinct

  7. Number of Species on Earth • About 1.7 million known • Mostly insects • Vertebrates comprise the fewest species

  8. Other types of Diversity • Ecosystem diversity • Genetic diversity • Genetic diversity is a critical factor to a species, the less genetically diverse a species, the more likely it is to go extinct

  9. Population Bottleneck

  10. Stop and Answer • Describe the 3 levels of biodiversity • Explain how biodiversity is important to ecosystems

  11. Biodiversity at Risk Mass Extinctions

  12. Current Extinctions • Between 1800 and 2000 up to 25% of all species may have gone extinct • Endangered species: likely to become extinct if steps are not taken to preserve it • Threatened species: has a declining population and is likely to become endangered if it is not protected

  13. Mass Extinction

  14. How do humans cause extinctions • Habitat destruction and fragmentation • Fragmentation is breaking ecosystems into smaller and smaller pieces • Example Ashburn

  15. Humans and extinctions • Introduction of invasive exotic species • An exotic species is not native to a region • An exotic species may become invasive if it has no natural predators • Examples: • Fire ants • Killer bees • Kudzu • Canadian thistle

  16. Humans and extinction • Harvesting, hunting, poaching • Poaching is illegal hunting • Excess harvesting and hunting leads to species decline

  17. Humans and Extiction • Pollution • Pesticides • Cleaning agents • Drugs

  18. Areas of Critical Biodiversity • Certain areas of the world contain a greater diversity of species than other areas • They have a large portion of endemic species, that is species that are native to an area • Example: in a tropical rain forest there may be 200 tree species in an acre, but in a temperate forest there is usually only about 25 endemic species per acre

  19. Tropical Rain Forests • Many of the plants in tropical rain forests have antibiotic or anti-cancer properies • Tropical rainforests are at ever increasing risk as land is cleared for farming and grazing and trees are sold for timber or burned

  20. Coral Reefs and Coastal Ecosystems • These areas are the nurseries for most of the fish on Mother Earth • Pollution is greatest along coasts worldwide because most of the big human cities are located along the coast • Overdevelopment is also causing destruction of dunes and wetlands which protect the coast • Overfishing is causing fish extinctions worldwide

  21. Biodiversity Hot Spots • Hot spots are the most threatened areas of high species diversity on Earthmost of the hotspots have lost 70% or more of their natural vegetation • When the vegetation goes, so do the animals • Mostly tropical rainforests, coastal areas and islands

  22. Hotspot Losses • Madagascar more than 80% of its 10,000 flowering plant species and 90% of its reptile species are endemic • Most live no where else on Earth • All 33 species of lemur are found only in Madagascar, this is 18% of all primate species on Earth • Madagascar has lost 18% of its forests

  23. HotSpots

  24. Biodiversity in thUSA • Contains 3 biodiversity hotspots • Florida Everglades • Hawaii • California coastal region • 3488 native plant species • 2124 are endemic • 565 threatened or endangered

  25. Stop and Answer • Describe 4 ways that species are threatened with extinction • Define endangered species and threatened species

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