Man and the Biosphere Program

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Man and the Biosphere Program

The Man and the Biosphere (MAB) program is a global system of biosphere reserves begun in 1986 and organized by the United Nations Educational, Social, and Cultural Organization (UNESCO ). MAB reserves are designed to conserve natural ecosystems and biodiversity and to incorporate the sustainable use of natural ecosystems by humans in their operation. The intention is that local human needs will be met in ways compatible with resource conservation . Furthermore, if local people benefit from tourism and the harvesting of surplus wildlife , they will be more supportive of programs to preserve wilderness and protect wildlife.

MAB reserves differ from traditional reserves in a number of ways. Instead of a single boundary separating nature inside from people outside, MAB reserves are zoned into concentric rings consisting of a core area, a buffer zone, and a transition zone. The core area is strictly managed for wildlife and all human activities are prohibited, except for restricted scientific activity such as ecosystem monitoring. Surrounding the core area is the buffer zone, where nondestructive forms of research, education, and tourism are permitted, as well as some human settlements. Sustainable light resource extraction such as rubber tapping, collection of nuts, or selective logging is permitted in this area. Preexisting settlements of indigenous peoples are also allowed. The transition zone is the outermost area, and here increased human settlements, traditional land use by native peoples, experimental research involving ecosystem manipulations, major restoration efforts, and tourism are allowed.

The MAB reserves have been chosen to represent the world's major types of regional ecosystems. Ecologists have identified some 14 types of biomes and 193 types of ecosystems around the world and about two-thirds of these ecosystem types are represented so far in the 276 biosphere reserves now established in 72 countries. MAB reserves are not necessarily pristine wilderness. Many include ecosystems that have been modified or exploited by humans, such as rangelands , subsistence farmlands, or areas used for hunting and fishing. The concept of biosphere reserves has also been extended to include coastal and marine ecosystems, although in this case the use of core, buffer, and transition areas is inappropriate.

The establishment of a global network of biosphere reserves still faces a number of problems. Many of the MAB reserves are located in debt-burdened developing nations, because many of these countries lie in the biologically rich tropical regions. Such countries often cannot afford to set aside large tracts of land, and they desperately need the short-term cash promised by the immediate exploitation of their lands. One response to this problem is the debt for nature swaps in which a conservation organization buys the debt of a nation at a discount rate from banks in exchange for that nation's commitment to establish and protect a nature reserve.

Many reserves are effectively small, isolated islands of natural ecosystems surrounded entirely by developed land. The protected organisms in such islands are liable to suffer genetic erosion , and many have argued that a single large reserve would suffer less genetic erosion than several smaller reserves which cumulatively protect the same amount of land. It has also been suggested that reserves sited as close to each other as possible, and corridors that allow movement between them, would increase the habitat and gene pool available to most species .

[Neil Cumberlidge Ph.D. ]