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A laboratory experimental investigation was conducted to define the action of rising bubbles with respect to heavy-metal enrichment at the sea surface. Analytical data (HMDE-differential pulse anodic stripping voltammetry technique) show possible enrichments of organic-bound Zn, Cu, Cd and Pb at the top of a laboratory bubble-extraction column filled with water samples collected in the Southern Tyrrhenian Sea. In consideration of analogy between natural and laboratory bubble-extraction processes, laboratory results, i.e., enriched-over-original concentration ratios, make it possible to assess the intrinsic heavy-metal flotation capability in marine waters.  相似文献   
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This study estimates the consequences of climate change on cropland with and without implementation of adaptation measures, paying special attention to the maintenance of soil organic carbon (C) stocks. We examine the possibility for regional sustainable agricultural management practice that combines both maintenance and gain in soil carbon level with profit maximization. Future scenarios of Regional Agricultural Production Systems (RAPS) were constructed for 2000–2070 based on linking the effects of global climate change, predicted change in productivity parameters for the main agricultural crops, land-use and soil database parameters. The RAPS were used to examine profitability and feasibility of alternative agricultural scenarios, based on an economic model. A number of recommendations for decision making were proposed based on an assessment of the efficiency of adaptation in animal husbandry and in the crop production sector, after analysis of current percentage of perennial grass in rotation in comparison with future economic scenarios. Figures in color are available at  相似文献   
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The report summarizes surveys on carbon inventories and initiatives on sustainable carbon cycling taken by the Research Center for Eco-Environmental Sciences, where the authors work/worked. The first part of the report, which appeared in the preceding issue of this journal, deals with the concept of sustainable carbon cycling, the historic evolution of carbon cycling processes in China, carbon pool enhancement, value addition, carbon sequestration and carbon balance. This very paper, as the second part of the report, covers the results of carbon dynamics modeling, emission inventories of various carbon-containing greenhouse gases and their potential abatement measures.  相似文献   
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Abstract: The angiosperm flora of Sri Lanka, which has been comparatively well studied by many eminent botanists for over two centuries, has a rich endemic component and also exhibits strong affinities to that of peninsular India Some of the 15 floristic regions recognized in the island have exceptionally rich, highly localized floras. But increased forest disturbances over the years have taken a heavy toll. A plea is made to conserve at least one sufficiently large forest reserve in each floristic region. A meaningful conservation program has been launched in the Sinharaja MAB Reserve; similar programs are urgently needed for other protected areas of the island.  相似文献   
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Leaching, depending on the acidity of the eluent, was investigated for K, Mg and Mn. The curves for the leachate concentration versus time could be described by a power function. Leaching from old needles exceeded leaching from young needles to a high degree, but the ratios of the leached elements were almost equal. A method for continuous measurements of pH change in solutions contacting plant materials was developed. The results were in agreement with data on acidity changes in water falling through spruce or beech canopies.  相似文献   
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Environment, Development and Sustainability - The objectives of this study across the highlands of Ethiopia were: (i) to characterize the association between soil organic carbon (SOC) stocks and...  相似文献   
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