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January 22-February 4, 2001 |
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If you choose to follow any links to the abstracts and/or complete text of articles, books, and documents listed below, you will be leaving the Strategian Web site. If you wish to return to this page from the Web page you are sent to, please use the Back option of your browser. Feature Items: S. Naeem, J.M.H. Knops, D. Tilman, K.M. Howe, T. Kennedy, and S. Gale Plant Diversity Increases Resistance to Invasion in the Absence of Covarying Extrinsic Factors. (... the invasion of an ecosystem by plants and/or animals that normally live outside the ecosystem and, therefore, do not have the same predators and other checks as the animals and plants that are native to a location, is a widespread, but poorly understood phenomenon. Biological invasion [as it is called] can potentially be destructive and costly economically and environmentally. Elton's hypothesis suggests that an important determinant of invasion success is resident biodiversity, arguing that high diversity increases the competitive environment of communities and makes them more difficult to invade. To test this hypothesis, the authors studied the performance of Crepis tectorum [an invasive, annual composite weed] in experimental prairie grassland plots and greenhouse plant assemblages in which resident species richness [biodiversity] was directly manipulated. The authors discovered a strong inverse association between resident diversity and invader performance as predicted by Elton's hypothesis. Higher resident diversity increased crowding, decreased available light, and decreased available nutrients all of which increased the competitive environment of diverse plant assemblages and reduced C. tectorum success. These results suggest that both Elton's hypothesis and its competitive mechanism may operate in nature, but covarying extrinsic factors [like disturbance, climate, or soil fertility] may obscure the negative impact of diversity on invader success as has been noted via observational studies of plant invasions -- from the text of the abstract) Oikos Volume 91, Number 1 (October 2000): 97-108. **An abstract of the article is currently available through the Web site of Oikos** Intergovernmental Panel on Climate Change Climate Change 2001: The Scientific Basis. (... one of the most comprehensive reports on global climate change yet issued. The Intergovernmental Panel on Climate Change [IPCC] was established by the United Nations Environmental Programme [UNEP] and the World Meteorological Organization [WMO] in 1988 to assess the scientific, technical and socio-economic information relevant for the understanding of human induced climate change, its potential impacts and options for mitigation and adaptation. This Third Assessment Report, issued by Working Group I of the IPCC, looks at the science behind past, present, and potential future climate change and whether that change can be attributed to human activities, natural events, or both. The report was produced by some 1,000 scientists around the world who served as authors, editors, and reviewers. The report describes the current state of understanding of the climate system and provides estimates of its projected future evolution and their uncertainties. Other keywords and phrases -- climate system, gases, global warming, greenhouse effect, greenhouse gas, temperature, warming -- from the text of the Summary and the IPCC Working Group II Web site) January 2001. **The complete text of the 20-page "Summary for Policymakers" highlighting the findings described in the entire report and the complete text of the entire report are available through the Web site of the IPCC.** How to find the above journals, magazines, and other publications? See Step 3: Locate of the Information Strategy for details. Questions about any or all of the above? Please let me know. |
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