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281.
282.
The Russian natural gas industry is the world's largest producer and transporter of natural gas. This paper aims to characterize the methane emissions from Russian natural gas transmission operations, to explain projects to reduce these emissions, and to characterize the role of emissions reduction within the context of current GHG policy. It draws on the most recent independent measurements at all parts of the Russian long distance transport system made by the Wuppertal Institute in 2003 and combines these results with the findings from the US Natural Gas STAR Program on GHG mitigation options and economics.With this background the paper concludes that the methane emissions from the Russian natural gas long distance network are approximately 0.6% of the natural gas delivered. Mitigating these emissions can create new revenue streams for the operator in the form of reduced costs, increased gas throughput and sales, and earned carbon credits. Specific emissions sources that have cost-effective mitigation solutions are also opportunities for outside investment for the Joint Implementation Kyoto Protocol flexibility mechanism or other carbon markets.  相似文献   
283.
This study aimed at statistically investigating the association between the internal exposure of children and young adults to uranium (U) and epidemiologically relevant external determinants of exposure. The investigation was performed with data from two studies within the framework of the German health-related environmental monitoring program: The German Environmental Survey for Children (GerES IV) conducted by the Federal Environment Agency (Umweltbundesamt) with data on 1,780 children 3–14 years of age and their home environment and the German Environmental Specimen Bank (ESB, section: human specimens) with data on 2,253 students 20–29 years of age. Both studies provided data on the U levels in human urine for all probands. GerES IV furthermore provided an extensive environmental and demographic database on, e.g., U levels in drinking water. The data from GerES IV and ESB were linked by GIS to spatially relevant exposure information, including background values of U in stream sediments and in upper and lower soils, U levels in mosses and particulate matter in the lower atmosphere, precipitation and elevation as well as forest density. Bivariate correlation analysis and two decision tree models showed moderate but significant associations between U in human urine and U levels in drinking water, stream sediments and upper and lower soils. Future investigations considering additional epidemiologically relevant data sets may differentiate the results. Furthermore, the sample design of future environmental epidemiology studies should take the spatial evaluation of the data into greater account.  相似文献   
284.

Goal and Scope

At the present, air borne particulate matter is in the focus of public and scientific interest. In this context, it makes sense to remember the buffer function of vegetation for particulate air pollutants, notwithstanding technical and traffic management measures. Since trees with large and dense crowns might be able to shade windows and minimise the turbulent dilution of pollutants, natural-scientific results and socio-scientific aspects will point to the potentials of vertical greening with creeping plants.

Methods

To differentiate the endogenous and exogenous element fractions, the pollution caused by dust that covers the façade climbing creepers leaves was removed by a polyvinyl-butyrale based stripping method. The cleaning success is proven by SEM-Scans. The results of cleaned and not cleaned leaf-samples from an inner-city vertical greening for the element concentrations of Al, Cd, Co, Cr, Cu, Fe, Ni, Pb, Pt, Rh, Sb and Zn between 1991 and 1997 are shown by AAS- and ICP-MS analyses.

Results and Conclusion

The results show the increasing element concentrations during the course of the separate vegetation periods. Due to the long investigation period, it is possible to detect historical aspects concerning pollution, such as the end of the use of leaded fuel and the introduction of the catalytic converters. The comparison of dust deposition data from different cities shows the relevance of the pollution filtering by vertical greenings with Japanese Creeper. The comparison of investigation results of sycamore leaves refer to entirely different filtering characteristics of the leaf-surfaces.

Recommendation and Perspective

If appropriate planning and maintenance is assured, vertical greening can be a useful contribution for air pollution control and neighbourhood improvement. As selected results from a survey show, from the citizens point of view, the aesthetical and psychosocial aspects of well-being are of more relevant than ecological arguments. Therefore it seems to be wise to implement the combined fields of interest.  相似文献   
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