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Economic liberalization in former socialist countries may have various implications for their environmental sustainability. Positive effects of this process are potentially associated with improved efficiency, investments into cleaner technologies, responsiveness to environmentally aware markets, and ending subsidies to heavy industries. On the other hand, market liberalization may result in weaker environmental controls, economic instabilities distracting attention from environmental issues, and increasing orientation towards profit-making leading to more intensive exploitation of natural resources. In addition, trade liberalization may result in shifts towards more pollution and resource-intensive industries. This article seeks to quantify effects of economic restructuring in Russia on air pollution from productive economic sectors in the 1990s. Air pollution in Russia had significantly declined in 1991-1999, however, this decline was largely due to economic decline, as the overall pollution intensity of the economy had decreased only slightly. The factors that affected the pollution intensity are: (1) a decrease in the combined share of industrial and transport activities in the economy and (2) changing pollution intensities of the industrial and transport sectors. The pollution intensity of the Russian industry had remained relatively stable during the 1990s. This was the result of the two opposite and mutually canceling trends: (a) increasing shares of pollution-intensive branches such as metal smelting and oil production vs. less pollution intensive manufacturing and (b) decline in pollution intensities within the industrial branches. The article proposes a methodology by which the contribution of both factors to the overall pollution intensity of the industrial sector can be quantified. The pollution intensity of the Russian transport sector appears to have declined in the first half of the 1990s and increased in the second half. The most recent trend can be explained by a rising proportion of private motorcars used for transportation of people and goods instead of traditional rail and other public transport. The findings of the paper demonstrate that shifts towards more pollution-, resource- and energy-intensive industries as a result of economic liberalization emerges as a significant negative factor of the process of economic transition threatening sustainability of emerging market economies. A research agenda to further investigate these impacts is proposed.  相似文献   
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In the tradition of the study of materials flows through society, the Substance Flow Analysis (SFA) method and its software tool SFINX are presented. SFA aims at providing the relevant information for a country’s overall management strategy regarding single substances or coherent groups of substances. Three modelling techniques and their possibilities and limitations are discussed: Bookkeeping, static modelling, and dynamic modelling. The computer program SFINX can be used for varoius purposes: (1) to obtain an overview of stocks and flows of a substance in, out and through a nation’s economy and environment for a specific year, (2) to trace the origins of specific pollution problems, and (3) to estimate the effectiveness of certain abatement measures. Each application has its own requirements with regard to data and modelling.  相似文献   
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Hansson LA  Hylander S  Sommaruga R 《Ecology》2007,88(8):1932-1939
In order to avoid environmental threats, organisms may respond by altering behavior or phenotype. Using experiments performed in high-latitude Siberia and in temperate Sweden, we show for the first time that, among freshwater crustacean zooplankton, the defense against threats from ultraviolet radiation (UV) is a system where phenotypic plasticity and behavioral escape mechanisms function as complementary traits. Freshwater copepods relied mainly on accumulating protective pigments when exposed to UV radiation, but Daphnia showed strong behavioral responses. Pigment levels for both Daphnia and copepods were generally higher at higher latitudes, mirroring different UV threat levels. When released from the UV threat, Daphnia rapidly reduced (within 10 days) their UV protecting pigmentation-by as much as 40%--suggesting a cost in maintaining UV protective pigmentation. The evolutionary advantage of protective pigments is, likely, the ability to utilize the whole water column during daytime; conversely, since the amount of algal food is generally higher in surface waters, unpigmented individuals are restricted to a less preferred feeding habitat in deeper waters. Our main conclusion is that different zooplankton taxa, and similar taxa at different latitudes, use different mixes of behavior and pigments to respond to UV radiation.  相似文献   
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Reducing emissions from deforestation and forest degradation (REDD) can be an effective and efficient means of mitigating climate change. However, the perceived equity in the distribution of financial incentives for REDD could also emerge as a critical issue in international negotiations. The design of reference levels, which provide the benchmark for crediting emissions reductions, affects the economic incentives for national participation in a REDD mechanism and thus the overall willingness to reach an agreement on REDD. This paper compares the equity impacts of five proposed reference level designs using a partial-equilibrium model. Tradeoffs among equity, environmental effectiveness and cost-efficiency indicate the proposals trigger similar aggregate emissions reductions but lead to different outcomes in efficiency and alternative measures of equity. If equity across countries is measured as the financial incentive provided relative to a country's forest carbon stock, then a REDD mechanism compensating a uniform share of at-risk carbon stocks is the most equitable. On the other hand, if equity is evaluated as the financial incentive relative to the opportunity costs of participating in REDD, then the most equitable approach would be compensating emissions reductions but withholding a part of the payments to compensate for carbon stocks, which also encourages broader country participation under our model.  相似文献   
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Environmental Science and Pollution Research - Rivers act as a natural source of greenhouse gases (GHGs). However, anthropogenic activities can largely alter the chemical composition and microbial...  相似文献   
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