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Preservation of the biological diversity and ecosystems in protected areas can be achieved through projects linking conservation of the protected areas with improved standards of living for resident peoples within surrounding buffer zones. This is the hypothetical claim of the integrated conservation and development project (ICDP) approach to protected area management. This paper, based on several years of experience with the Ranomafana National Park Project in Madagascar, questions the major assumptions of this approach from ethical and practical perspectives. The four basic strategies available to ICDPs – protected areas, buffer zones, compensation, and economic development – are analyzed and shown to be deficient or untested in the case of Ranomafana. Recommendations are made to explore conservation models other than the western conception of the national park, to modify the notion of a buffer zone outside the protected area, to redistribute money or other resources directly to the poor people living in and around the protected areas, and to eliminate the middle men in the development business. An appeal is made to focus on local education, organization and discipline in order to promote self-determination and self-reliance among resident peoples of protected areas. The paper argues that a public works program, similar to the Roosevelt administration's Civilian Conservation Corps of the 1930s, funded through a hard-currency endowment or other innovative financing mechanism, should be tried as a replacement for the currently questionable ICDP approach at Ranomafana.  相似文献   
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Regional Environmental Change - Water is a fundamental component of the ecological integrity, economic development, and sustainability of northern regions, as well as the health and well-being of...  相似文献   
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This paper briefly describes waste treatment trends in Sweden and describes an example of state-of-the-art treatment in a local integrated waste treatment system (Bor?s). The focus is on treatment of household waste, to illustrate what can be done to establish a sustainable waste treatment system with high recovery of materials and energy. The various processes have resulted in a low amount of landfilled household waste, and high proportions of recovered energy and materials. Heat, electricity, vehicle fuel and fertilizers, metals and construction materials are recovered from the local waste in Bor?s, with less than 4% of domestic waste being sent to landfill.  相似文献   
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This paper reviews progress in phytoextraction of soil elements and illustrates the key role of hyperaccumulator plant species in useful phytoextraction technologies. Much research has focused on elements which are not practically phytoextracted (Pb); on addition of chelating agents which cause unacceptable contaminant leaching and are cost prohibitive; and on plant species which offer no useful phytoextraction capability (e.g., Brassica juncea Czern). Nickel phytoextraction by Alyssum hyperaccumulator species, which have been developed into a commercial phytomining technology, is discussed in more detail. Nickel is ultimately accumulated in vacuoles of leaf epidermal cells which prevents metal toxicity and provides defense against some insect predators and plant diseases. Constitutive up-regulation of trans-membrane element transporters appears to be the key process that allows these plants to achieve hyperaccumulation. Cadmium phytoextraction is needed for rice soils contaminated by mine wastes and smelter emissions with 100-fold more soil Zn than Cd. Although many plant species can accumulate high levels of Cd in the absence of Zn, when Cd/Zn>100, only Thlaspi caerulescens from southern France has demonstrated the ability to phytoextract useful amounts of Cd. Production of element-enriched biomass with value as ore or fertilizer or improved food (Se) or feed supplement may offset costs of phytoextraction crop production. Transgenic phytoextraction plants have been achieved for Hg, but not for other elements. Although several researchers have been attempting to clone all genes required for effective hyperaccumulation of several elements, success appears years away; such demonstrations will be needed to prove we have identified all necessary processes in hyperaccumulation.  相似文献   
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On November 5, 1984, The Dow Chemical Company issued a report entitled: “Point Sources and Environmental Levels of 2378-TCDD on the Midland Plant Site of The Dow Chemical Company and in the City of Midland, Michigan.” This report is based upon the efforts of a 22-person task force who dedicated approx. 21 months of effort to the generation and analysis of over 6000 analytical data points regarding specific CDD/CDF concentrations in the four basic environmental elements of air, earth, fire (incineration), and water. A summarization of this study will be presented which includes methodology, analytical QA-QC criteria, and representative soil analyses, as they pertain to the survey conclusions.  相似文献   
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