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Salit Kark Department of Evolution, Systematics and Ecology

Conservation Biology (Ecology) Lecture 2 Oct 2009. Salit Kark Department of Evolution, Systematics and Ecology The Silberman Institute of Life Sciences The Hebrew University of Jerusalem. What is Biodiversity?

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Salit Kark Department of Evolution, Systematics and Ecology

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  1. Conservation Biology (Ecology) Lecture 2 Oct 2009 Salit Kark Department of Evolution, Systematics and Ecology The Silberman Institute of Life Sciences The Hebrew University of Jerusalem

  2. What is Biodiversity? "...the diversity within species, between species and of ecosystems” (UN Convention on Biological Diversity 1992) The within species component has been defined as “the frequency and diversity of different genes and/or genomes...” (IUCN 1993)

  3. What is Biodiversity? “the millions of plants, animals, and microorganisms, genes they contain, and the intricate ecosystems they help build into the living environment” (World Wildlife Fund, 1989) “the variety of life on Earth at all its levels, from genes to ecosystems, and the ecological and evolutionary processes that sustain it.” (Gaston 1996)

  4. Patterns of biodiversity How many species are there? Which groups do they belong to? Why is it so unevenly distributed?

  5. Patterns of biodiversity Where is it found? What are the main correlates?

  6. Conservation International’s hotspots

  7. Global environmental changes Climate change Habitat fragmentation and destruction Invasion by alien species Major threat to biodiversity, to the functioning of ecological systems and to the services provided to humanity by nature (threshold?) Opportunity to address research questions central to conservation ecology (“grand natural experiment”)

  8. Human related factors shaping biodiversity: We will deal with some of these in more detail during our course: • Fragmentation and habitat destruction • Urbanization and changes in land use • Agriculture (type, matrix) • Introduced species • Pollution • Climate changes (changes in climatic means and extremes, competition, communities, distributions ranges…)

  9. Biodiversity decline: Genetic diversity Number of populations Number of species Number of endemic and rare species Ecosystems and their services

  10. Biodiversity and extinction today Current extinction rates are likely occurring at 100 to 1000 times the normal background extinction rates. If these continue over the centuries, there will be extinction levels as in the Big Five.

  11. Source: World Conservation Monitoring Centre, "Global Biodiversity" Chapman & Hall, London, 1992).

  12. One of the differences from past extinctions is the rapid pace of today's extinctions. Ecologists estimate that we have lost hundreds of thousands of species in the past 50 years. Experts predict that if present trends continue, we are likely to lose half of all living species within the next century. Certain groups and regions are disappearing faster: Almost half of all plant species could be facing extinction (Science, Nov 2002) Tropical forests, Mediterranean regions…

  13. Ivory-billed woodpecker Local Extinctions on Islands: Human Impact Over History Many documented extinctions from the recent past have occurred on islands (e.g. New Zealand, Hawaii and Mauritius) but some prominent continental exceptions (such as passenger pigeons, some species of buffalo and mastodon) dodo

  14. The last captive specimen of the marsupial tiger died in a Tasmanian zoo in 1936. No living specimen has been verified since, but sporadic reports persist in Tasmania, Victoria, and Western Australia.

  15. Evidence over past 2,000 years shows major human effects: 20% of birds in Pacific region gone due to human colonization of islands 60 endemic species on Hawaiian islands went extinct 1,500 yrs ago after settlers arrived 44 species (including flightless moas) went extinct in New Zealand after Polynesian settlers arrived.

  16. Tropical Forests • Tropical forests occupy only 7% of the land area on Earth but contain 50% of the species • Human impact is more recent in tropics • currently have highest population growth rates • Highest rates of habitat loss • Africa and Americas 1980-1990: 0.7% tropical forest lost per year • Asian tropical forest worse: 1.1% loss per year • Amazon forest largest continuous forest on Earth. Forest destruction rapid and large scale.

  17. Biodiversity: Extinction by numbers Stuart Pimm and Peter Raven 2000. Nature403,843-5 How can we calculate the rate of species extinctions from habitat fragments? There have been only a few such estimates, but combining the rate of habitat loss, the species-area relationship and survivorship curves gives a crude extinction curve.

  18. ...יש הכחדות בישראל? גנים? מינים מערכות

  19. כיום ידוע על 39 מיני צמחים שנכחדו בישראל, מהם 69% נכחדו עד אמצע שנות השישים . צמחים נכחדים בישראל רון פרומקין ,אבי שמידע ,יובל ספיר ,אורי פרגמן –ספיר ונעם לוין מתוך :פרומקין ,ר ',חנין ,ד 'ואידלמן ,ע '(עורכים) .2004 סימני חיים, מרכז השל לחשיבה ומנהיגות סביבתית ,מכון ירושלים לחקר ישראל והוצאת בבל .

  20. מתוך :פרומקין ,ר ',חנין ,ד 'ואידלמן ,ע '(עורכים) .2004 סימני חיים, מרכז השל לחשיבה ומנהיגות סביבתית ,מכון ירושלים לחקר ישראל והוצאת בבל . צמחים נכחדים בישראל רון פרומקין ,אבי שמידע ,יובל ספיר ,אורי פרגמן –ספיר ונעם לוין

  21. למה לשמור? Why conserve biodiversity? The value of biodiversity Direct: Economic, resources Indirect: Water and soil protection, climate regulation… Existence (inherent), ethical values

  22. The value of biodiversity Source: The Economic Value of Biodiversity IUCN —The World Conservation Union

  23. The value of biodiversity (Meffe 1997)

  24. The value of biodiversity – forest example Source:The Economic Value Of Biodiversity IUCN —The World Conservation Union

  25. Why conserve biodiversity? The value of biodiversity Direct: Economic, resources Indirect: Water and soil protection, climate regulation… Existence (inherent), ethical values

  26. Some ethical arguments for preserving biodiversity (Primack 2002): • Each species has a right to exist • Species are interdependent (The Rivet hypothesis) • We have responsibility as stewards • Responsibility for future generations • and more…

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