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Biodiversity Assessment

The Global Biodiversity Assessment completed by 1500 scientists under the auspices of UNEP in 1995 updated what we know, or more correctly how little we know, about global biological diversity at the ecosystem, species and genetic levels (Heywood, 1995). The assessment was uncertain of the total number of species on Earth within an order of magnitude. Of its working figure of 13 million species, only 13% have been scientifically described. Ecological community diversity is also poorly known, as is its relationship to biological diversity, and genetic diversity has been studied for only a small number of species. The effects of human activities on biodiversity have increased so greatly that the rate of species extinctions is rising to hundreds or thousands of times the background level. These losses are driven by increasing demands on species and their habitats, and by the failure of current market systems to value biodiversity adequately. The Assessment calls for urgent action to reverse these trends (Heywood, 1996).

There has been a new recognition of the importance of protecting marine and aquatic biodiversity. The first quantitative estimates of species losses due to growing coral reef destruction predict that almost 200,000 species, or one in five presently contributing to coral reef biodiversity, could die out in the next 40 years if human pressures on reefs continue to increase (Reaka-Kudla, 1996).

Since Rio, many countries have improved their understanding of the status and importance of their biodiversity, particularly through biodiversity country studies such as those prepared under the auspices of UNEP/GEF. The United Kingdom identified 1250 species needing monitoring, of which 400 require action plans to ensure their survival (Bendall, 1996). Protective measures for biodiversity, such as legislation to protect species, can prove effective. In the USA, almost 40 percent of the plants and animals protected under the Endangered Species Act are now stable or improving as a direct result of recovery efforts (USFWS, 1994). Some African countries have joined efforts to protect threatened species through the 1994 Lusaka Agreement, and more highly migratory species are being protected by specialized cooperative agreements among range states under the Bonn Convention.

There is an emerging realization that a major part of conservation of biological diversity must take place outside of protected areas and involve local communities. The extensive agricultural areas occupied by small farmers contain much biodiversity that is important for sustainable food production. Indigenous agricultural practices have been and continue to be important elements in the maintenance of biodiversity, but these are being displaced and lost. There is a new focus on the interrelationship between agrodiversity conservation and sustainable use and development practices in smallholder agriculture, with emphasis on use of farmers' knowledge and skills as a source of information for sustainable farming (Global Environmental Change: Human and Policy Implications, 1995; Uitto and Ono, 1996).

Perhaps even more important than the loss of biodiversity is the transformation of global biogeochemical cycles, the reduction in the total world biomass, and the decrease in the biological productivity of the planet (Golubev, in litt.). While quantitative measurements are not available, the eventual economic and social consequences may be so significant that the issue requires further attention.

References and Sources

Bendall, Roger. 1996. "Biodiversity: the follow up to Rio". The Globe 30:4-5, April 1996.

Global Environmental Change: Human and Policy Implications. 1995. Special issue on "People, Land Management and Environmental Change", Vol. 3, No. 4, September 1995.

Golubev, Genady N. (Moscow University) In litt. 29 June 1996.

Heywood, V.H. (ed.). 1995. Global Biodiversity Assessment. United Nations Environment Programme. Cambridge University Press, Cambridge.

Heywood, V.H. 1996. "The Global Biodiversity Assessment". The Globe, 30:2-4, April 1996.

Reaka-Kudla, Marjorie. 1996. Paper presented at American Association for Advancement of Science, February 1996. Quoted in Pain, Stephanie. "Treasures lost in reef madness". New Scientist, 17 February 1996.

Uitto, Juha I., and Akiko Ono (eds). 1996. Population, Land Management and Environmental Change. The United Nations University, Tokyo.

USFWS. 1994. U.S. Fish and Wildlife Service report to Congress, cited in news release 21 July 1994.
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