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171.
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Economic growth,biodiversity loss and conservation effort   总被引:6,自引:0,他引:6  
This paper investigates the relationship between economic growth, biodiversity loss and efforts to conserve biodiversity using a combination of panel and cross section data. If economic growth is a cause of biodiversity loss through habitat transformation and other means, then we would expect an inverse relationship. But if higher levels of income are associated with increasing real demand for biodiversity conservation, then investment to protect remaining diversity should grow and the rate of biodiversity loss should slow with growth. Initially, economic growth and biodiversity loss are examined within the framework of the environmental Kuznets hypothesis. Biodiversity is represented by predicted species richness, generated for tropical terrestrial biodiversity using a species-area relationship. The environmental Kuznets hypothesis is investigated with reference to comparison of fixed and random effects models to allow the relationship to vary for each country. It is concluded that an environmental Kuznets curve between income and rates of loss of habitat and species does not exist in this case. The role of conservation effort in addressing environmental problems is examined through state protection of land and the regulation of trade in endangered species, two important means of biodiversity conservation. This analysis shows that the extent of government environmental policy increases with economic development. We argue that, although the data are problematic, the implications of these models is that conservation effort can only ever result in a partial deceleration of biodiversity decline partly because protected areas serve multiple functions and are not necessarily designated to protect biodiversity. Nevertheless institutional and policy response components of the income biodiversity relationship are important but are not well captured through cross-country regression analysis.  相似文献   
173.
The optimal spatial design of protected reserves requires attention to the biological mechanisms underlying community organization, and sustaining ecosystem services. Identifying the key mechanisms is especially difficult in species-rich ecosystems. We investigate the example of the tropical rainforest, a biome that is under threat of continuing fragmentation, yet which shelters the majority of living species on Earth. Simple dynamic and spatially explicit simulations, which model the dynamics of plant communities, allow us to elucidate the interplay between patterns of fragmentation and seed dispersal mechanisms in maintaining biodiversity.  相似文献   
174.
Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were determined in pooled samples of ringed seal (Phoca hispida) blubber, beluga (Delphinapterus leucas) blubber and polar bear (Ursus maritimus) liver and fat from several areas throughout the Canadian north and compared to mean PCB and HCB levels in the same samples. All seal samples, and all but one polar bear sample, had detectable 2,3,7,8-TCDD at concentrations ranging from 2 to 37 ng/kg, but TCDD was not found in beluga blubber (< 2 ng/kg). All seal samples and one of three beluga samples contained 2,3,7,8-TCDF at levels of 2 to 7 ng/kg, but TCDF was not found in any bear sample. TCDF must therefore be cleared rapidly by polar bears. No other PCDF congeners were found at detection limits of 4 to 8 ng/kg. OCDD concentrations in seal blubber and polar bear samples ranged from not detected (< 8 ng/kg) to 43 ng/kg. No apparent biomagnification of TCDD, OCDD or TCDF occurred from seal to bear fat, similar to previous findings for DDT, and unlike SigmaPCBs and HCB which biomagnified 6- to 17-fold. Highest concentrations of 2,3,7,8-TCDD and OCDD in seals and bears were found in the central Canadian Arctic Archipelago, and lowest were found in Hudson Bay, the reverse of PCB concentration distribution. The reason for higher levels of TCDD and OCDD in the Arctic than in the sub-Arctic is suggested to be trans-polar movement of aerosols with combustion-related origins in Eurasia. Levels of 2,3,7,8-TCDF were more evenly distributed throughout the North, and were positively correlated with PCB, but not with HCB or 2,3,7,8-TCDD levels in seals.  相似文献   
175.
The challenges faced by coastal protected areas in both promoting highly attractive sites and preserving the natural attributes of these sites have been given a new dimension with the opportunities presented by ecotourism. Realising the market potential of a protected area and, at the same time, conserving the unique features of an area is a difficult task. This paper explores the possibilities that backpacker tourism may offer the Quarantine Station in Sydney Harbour National Park, in Australia. The Quarantine Station is a significant cultural heritage site that is located in a sensitive coastal national park within Sydney's metropolitan area.  相似文献   
176.
Environmental Science and Pollution Research - Large-scale wastewater schemes rely on multi-barrier approach for the production of safe and sustainable recycled water. In multi-barrier wastewater...  相似文献   
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