Conserving Biodiversity A Research Agenda for Development Agencies (1992) / Chapter Skim
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1 BIODIVERSITY AND DEVELOPMENT
1 BIODIVERSITY AND DEVELOPMENT
Pages 12-34
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From page 12... ...
We also live in a world in which thousands of people, primarily women and young children in developing nations, die each day of starvation or of diseases related to starvation; in which human beings consume well over a third of total terrestrial photosynthetic productivity; and in which human activity threatens, over the next few decades, to eliminate a quarter of the world's species species we may not use directly, but on which our survival depends in many other ways. During the 1980~ the total human population increased by about 0.8 billion people (from about 4.5 to 5.3 billion)
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From page 13... ...
The level of concern among world leaders, including the international development agencies, has risen. Many are rethinking their priorities with respect to the allocation of resources to slow the degradation.
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From page 14... ...
Species diversity normally refers to the diversity among species, whereas genetic diversity refers to the diversity within species. Ecosystem (derived from "ecological system")
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From page 15... ...
It is easier to comprehend (and measure) the ecological services that biological diversity provides more locally in protecting watersheds, cycling nutrients, combating erosion, enriching soil, regulating water flow, trapping sediments, mitigating pollution, and controlling pest populations.
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From page 16... ...
Although the accelerated pace of deforestation in the humid tropics has drawn widespread attention and is of immediate concern, the degradation of natural ecosystems and habitats, and the loss of their characteristic species diversity, are occurring in nearly every part of the globe as human populations and their support systems expand. We are at a critical juncture for the conservation and study of biological diversity; such an opportunity will not occur again.
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From page 17... ...
The environmental changes affecting biodiversity today have a different origin, order, and magnitude than those recorded in geologic annals. Today, the rate and scale of environmental changes brought about by human activities have increased to the point where a great many species may not have sufficient time or space in which to migrate or adapt.
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From page 18... ...
Unlike these currently threatened species, or those whose fate is now part of the geologic record, human beings can decide not to choose extinction. We can change our behavior and stop the acceleration of environmental degradation and species loss, thereby safeguarding species, their habitats, and our own future options for their use and enjoyment.
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From page 19... ...
To date, some 1.4 million kinds of organisms have been assigned scientific names, but coverage is complete for only a few well-studied taxonomic groups such as vertebrates, angiosperms, and butterflies (Wilson, 1988; see table 1-11. Most groups and many major habitats such as coral reefs, the deep sea floor and thermal vents, tropical soils and forest canopies, remain poorly studied.
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From page 20... ...
20 TABLE 1-1 Numbers of Described Species of Living Organisms BIODIVERSITY Kingdom and Major No. of Described Subdivision Common Name Species Totals Virus Viruses 1 ,000 (order of magnitude only)
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From page 21... ...
One-half of the total species diversity of the Earth may be found in the tropical forests and is, therefore, threatened by their destruction or degradation. If current trends continue, almost all the remaining tropical forests will be severely damaged or reduced to small patches within the next few decades, resulting in the extinction of many as yet unknown plant species (Raven, 19881.
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From page 22... ...
Little is being done to investigate the enormous numbers of legume species that exist in the tropics: 6,000 can be found in Latin America alone; of these, an estimated 2,000 or more are threatened with extinction as the forests of Latin America are degraded and disappear. Unless work on these species is undertaken immediately, most will never have been studied in relation to their utility, nor will they have been incorporated into botanical gardens or seed banks.
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From page 23... ...
Mycorrhizal fungi, which form symbiotic relationships with plant roots and enhance mineral nutrient uptake by their host plants, are critical links between the soil and plant components of most terrestrial ecosystems, and have been shown to have significant impacts on sustainable crop and forest management, as well as on the success of environmental restoration efforts (Harley and Smith, 1983; Miller, 1985; Amaranthus and Perry, 1987; Cook, 1991~. These fungi, however, are insufficiently studied, with most attention being devoted to those relatively few associated with economically important plants.
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From page 24... ...
Invertebrates Our knowledge of invertebrate species diversity, like that of microorganisms, is poor for most of the world, especially soil and marine environments, and tropical forests. No more than 10 percent of
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From page 25... ...
Invertebrates such as corals and some mollusks can substantially modify the physical structure of the marine environment by building reefs. Marine grazers, such as mollusks and echinoderms, can reduce the structural complexity of the marine environment by removing marine macroalgae and angiosperms.
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From page 26... ...
The alterations of habitat, on all scales, that are taking place in tropical regions thus result in far greater incidence of invertebrate species loss than would alterations on a similar scale in temperate regions. Studies of invertebrates do not reflect either their numbers or their importance in ecosystems, which represents a primary constraint of biodiversity research as a whole.
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From page 27... ...
In the same sense that tropical rain forests might contain many species whose products could be of great use, fish communities may include members whose nutritional modes, defense mechanisms, behavior, or growth characteristics could be applied in the production of proteins, medicines, or fertilizers, and in the management of aquatic habitats. In comparison to other taxonomic groups, there are few undescribed species of reptiles, birds, and mammals.
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From page 28... ...
A number of tropical lakes, large and small, support high levels of fish endemism and merit study not only because of their inherent importance for science, but also because of their susceptibility to the effects of exotic fish introductions. The unique circumstances under which the biota of tropical lakes has evolved and the likelihood of alteration due to development pressures make these lakes important sites for expanded scientific attention.
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From page 29... ...
, the variety of ecosystems it contains, and the difficulties involved in exploring and studying the life of the sea have hampered efforts to treat marine biodiversity more comprehensively. Marine organisms have long been used in cell biology and other areas of basic biological research, and certain communities in particular, coastal wetlands, mangrove forests, and coral reefs (the species richness of which is often compared to that of tropical rain forests)
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From page 30... ...
Above and beyond these commodity values, marine organisms are critical determinants of the structure and function of the global ecosystem. Marine phytoplankton, for example, are the foundation of marine food chains and play an important role in atmospheric dynamics.
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From page 31... ...
IMPLICATIONS FOR DEVELOPMENT AGENCIES Biological diversity reaches its highest levels, and faces its greatest risks, in the developing nations of the world, primarily because of intensive resource exploitation and the extensive alteration of habitats. This is due in part, however, to international markets, development policies, and lending practices that transfer financial resources from developing countries to industrial countries and undermine the capacity of developing countries to sustainably manage their resources.
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From page 32... ...
In many areas, expanding demand and declining local supplies have led to excessive harvest rates, and acute fuelwood shortages, and subsequent decline in soil and water resources. Developing renewable, cost-effective alternative energy sources, sustainable agroforestry systems, and more productive sources of firewood, charcoal, and timber will require greater attention to potentially useful species and genetic resources (NRC, 1991a)
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From page 33... ...
Finally, development agencies must have a "built-in" capacity to review outcomes, monitor practices, and recommend adjustments in policies that affect the status of biological diversity. Several development agency research programs have begun to reflect these needs.
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From page 34... ...
The research agenda outlined in the remainder of this report is intended to assist development agencies in their efforts to respond to these research needs Research cannot, in and of itself, conserve biodiversity in developing nations any more than it can in the developed nations. What research can do, however, is provide the people and the leaders of these nations with information that may help them to improve their lives, while securing the biological legacy on which their livelihood depends.
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