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141.
Summary Environmental degradation in the Asian Pacific area developing countries continues and has probably increased since the Stockholm Conference of 1972. The causes for this continued environmental degradation in Asia are analyzed. The paper assesses the actions of the International Assistance Agencies in providing support for the Asian developing countries since Stockholm. The Asian Development Bank project on Economic Policies for Sustained Development is described, and advocated as an important first step in a strategy moving towards economic-cum-environmental sustainability. Drastic changes and bold initiatives are suggested and required to establish true sustainable development for the developing countries.Dr Harvey F. Ludwig is Chairman of SEATEC International Consulting Engineers. He is a regular contributor to this journal.  相似文献   
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Conclusion  The need is urgent, if the ongoing rapid degradation of the remaining precious eco-systems of the developing countries are to be put under control while there is still time, for developing a procedure by which the real world intrinsic meaningfulness to people of precious eco-systems is recognized by assigning them monetary values to be considered in benefit/cost analyses. The procedures recommended by the U.S. Corps of Engineers and Resources of the Future for use in the USA seem to be much too complex for application in developing countries in the foreseeable future. Rather a very pragmatic approach is recommended based on actual experience in money outlays for such protection in USA projects, with the amounts modified to suit developing country conditions. Hopefully the IAAs (Multilateral Development Banks, Bilaterials, U.N. Agencies) will carry out the recommended R&D studies to produce a prescribed methodology recognized by economic, environmental, and political decision makers of both the IAAs and the DCs to be appropriate for use in planning and evaluating DC projects.  相似文献   
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Kammesheidt L 《Ambio》2002,31(3):243-250
Secondary forests regrowing on abandoned agricultural land constitute an important, albeit widely overlooked, component in the landscape matrix of tropical lowland America. These 'new' forest resources on private land-holdings derive either from unsustainable cattle-ranching practices of better-off farmers or are part of the crop/fallow system of resource-poor farmers. If previous land use was light, secondary forest management may offer an interesting use option to better-off farmers, providing that subsidies for stand improvement are given. Improved fallow systems using partly the successional vegetation may be a way to establish sustainable small-scale agriculture for resource-poor farmers. Given some technical and financial input, land-use systems based on secondary vegetation could play a vital role both in sustainable landscape management and biodiversity conservation.  相似文献   
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A methodology for determining regional ozone design values and the expected number of exceedances is described. The methodology was applied to data bases for one year or less from four U.S. urban areas: Houston, Los Angeles, Philadelphia, and St. Louis. The effects of reducing numbers of stations in a network were tested, and it was concluded that networks of nine or ten appropriately selected stations are adequate for estimating design values. Using the methodology described, the expected number of exceedances tends to be underestimated when using smaller networks; however, this appears to be an artifact of the conservative approach taken in developing the methodology.  相似文献   
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It is shown how the Goetz Aerosol Spectrometer can be used to determine the particle size distribution of a specific component of a mixed atmospheric aerosol. The method requires no micrographic counting, but does require that sensitive quantitative chemical analysis methods be available for the compounds of interest. The accuracy of the method and the sensitivity limitations are briefly discussed.  相似文献   
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