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Halina Szejnwald Brown Martin de Jong David L. Levy 《Journal of Cleaner Production》2009,17(6):571-580
Global Reporting Initiative (GRI) is the best-known framework for voluntary reporting of environmental and social performance by business worldwide. Using extensive empirical data, including interviews and documentary analysis, we examine GRI's organizational field and conclude that since its modest beginnings in 1999 GRI has been by several measures a successful institutionalization project. But the institutional logic of this new entity, as an instrument for corporate sustainability management, leaves out one of the central elements of the initial vision for GRI: as a mobilizing agent for many societal actors. This emergent logic reflects GRI's dominant constituency – large global companies and financial institutions and international business management consultancies – and not the less active civil society organizations and organized labor. We attribute these developments to factors such as building GRI within the existing institutional structures; the highly inclusive multistakeholder process; and the underdeveloped base of information users. From the institutional theory perspective, this case shows how the process of institutionalization is deeply affected by initial strategies of the founders, and how it reproduces existing power relations. From the governance perspective, this case leads us to question the power of commodified information to mobilize civil society and to strengthen governance based on partnerships. 相似文献
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上海中心城区苏州河沿岸排水系统降雨径流水文水质特性研究 总被引:4,自引:0,他引:4
为了解城市合流制管道系统降雨径流的水文水质变化过程与特征,于2007年7~9月对上海中心城区合流制排水系统(CSS)4类强度降雨(小雨、中雨、大雨和暴雨)的降雨量、径流量和污染浓度进行了同步连续监测与分析.结果表明,径流过程线滞后于降雨过程线约15~25 min,形态与降雨过程线相似,波动幅度低于降雨过程线.4类强度降雨的径流系数分别为:0.33、 0.62、 0.67和0.73.CSS基本存在30/30标准的降雨径流初始冲刷现象,污染物浓度过程线滞后于降雨过程线约30~40 min. 4类强度降雨径流的pH值和重金属Cu、Zn、Cr、Cd、Pb、Ni的事件平均浓度(EMC)均符合地表水环境质量标准Ⅴ类水要求,COD、BOD5、NH+4-N和TP的EMC的变化范围分别为225.0~544.1、 31.5~98.9、 8.9~44.2和1.98~3.52 mg·L-1,平均分别超过Ⅴ类水标准9.3、 5.6、 11.7和6.1倍,接近国外城市CSS的平均污染水平.SS与COD、BOD5、NH+4-N和TP在P<0.01水平上均具有一定的正相关性(R为0.359~0.736),颗粒态有机类和营养类污染物的比例平均为70.21%. 相似文献
128.
Background, aim, and scope Compared to other micropollutants such as pesticides or pharmaceuticals, less attention has been paid to biocides so far. A prioritisation of the biocides currently used in Switzerland in terms of pollution of waters revealed that quaternary ammonium compounds (QAC), the isothiazolinones chloromethylisothiazolinone and benzisothiazolinone as well as Irgarol exhibit the highest risk potential. The QAC benzalkoniumchloride (BAC) and didecyldimethylammoniumchloride (DDAC-C10) are used in considerable amounts and have a high biological activity. Materials and methods The emissions of selected QAC in waters and soil and the predicted environmental concentrations (PECs) were estimated by means of a substance flow analysis (SFA). The study was based on data from the Swiss products register, on literature, contacts to producers and users as well as on own assumptions. Results and discussion The consumption of BAC (four homologues) and DDAC-C10 in biocidal applications in Switzerland amounts to 90 and 30 tons annually. The most important applications are disinfectants for public health areas, food and feed areas as well as wood preservatives. The total emissions to the environment of all five substances account for approximately 11?t/a. The PECs in surface waters and sediments vary from values slightly lower than the predicted no-effect concentration (PNEC) to roughly three orders of magnitude below the PNEC. However, concentrations above the PNEC are possible at certain locations, particularly downstream of wastewater treatment plants (WWTP) effluents and sewer overflows. Effects on aquatic organisms can therefore not be excluded. Three BAC homologues could not be assessed, as there were no PNEC values available. Conclusions The contribution of emissions from WWTP (punctual emissions) to the environment is only about one tenth and relatively low compared to diffuse emissions. This means that measures for the emission reduction focussing only on end-of-pipe solutions in WWTP will not reduce the emissions significantly. Moreover, for the evaluation of measures, attention has to be paid to the fact that biocides such as the selected QAC are often also applied in non-biocidal applications (e.?g. three times higher volumes in the case of BAC). Recommendations and perspectives SFA serves as a useful tool for early recognition of environmental problems caused by chemicals. This allows recommending appropriate risk reduction measures in the production, the use and the end-of-life phase. It is advisable to use the SFA already in the development stage of chemicals and later on as a quality control tool. The relevant sources of chemicals and sinks in the environment can thus be determined in complex systems, even in absence of extensive measurements or product registers with consumption figures by means of estimations and scenarios. 相似文献
129.
Robert L. Heath Allen S. Lefohn Robert C. Musselman 《Atmospheric environment (Oxford, England : 1994)》2009,43(18):2919-2928
Ozone interacts with plant tissue through distinct temporal processes. Sequentially, plants are exposed to ambient O3 that (1) moves through the leaf boundary layer, (2) is taken up into plant tissue primarily through stomata, and (3) undergoes chemical interaction within plant tissue, first by initiating alterations and then as part of plant detoxification and repair. In this paper, we discuss the linkage of the temporal variability of apoplastic ascorbate with the diurnal variability of defense mechanisms in plants and compare this variability with daily maximum O3 concentration and diurnal uptake and entry of O3 into the plant through stomata. We describe the quantitative evidence on temporal variability in concentration and uptake and find that the time incidence for maximum defense does not necessarily match diurnal patterns for maximum O3 concentration or maximum uptake. We suggest that the observed out-of-phase association of the diurnal patterns for the above three processes produces a nonlinear relationship that results in a greater response from the higher hourly average O3 concentrations than from the lower or mid-level values. The fact that these out-of-phase processes affect the relationship between O3 exposure/dose and vegetation effects ultimately impact the ability of flux-based indices to predict vegetation effects accurately for purposes of standard setting and critical levels. Based on the quantitative aspect of temporal variability identified in this paper, we suggest that the inclusion of a diurnal pattern for detoxification in effective flux-based models would improve the predictive characteristics of the models. While much of the current information has been obtained using high O3 exposures, future research results derived from laboratory biochemical experiments that use short but elevated O3 exposures should be combined with experimental results that use ambient-type exposures over longer periods of time. It is anticipated that improved understanding will come from future research focused on diurnal variability in plant defense mechanisms and their relationship to the diurnal variability in ambient O3 concentration and stomatal conductance. This should result in more reliable O3 exposure standards and critical levels. 相似文献
130.
Rainfall trends in twentieth century over Kerala,India 总被引:1,自引:0,他引:1
K.N. Krishnakumar G.S.L.H.V. Prasada Rao C.S. Gopakumar 《Atmospheric environment (Oxford, England : 1994)》2009,43(11):1940-1944
Attempts were made to study temporal variation in monthly, seasonal and annual rainfall over Kerala, India, during the period from 1871 to 2005. Longterm changes in rainfall determined by Man-Kendall rank statistics and linear trend. The analysis revealed significant decrease in southwest monsoon rainfall while increase in post-monsoon season over the State of Kerala which is popularly known as the “Gateway of summer monsoon”. Rainfall during winter and summer seasons showed insignificant increasing trend. Rainfall during June and July showed significant decreasing trend while increasing trend in January, February and April. Hydel power generation and water availability during summer months are the concern in the State due to rainfall decline in June and July, which are the rainiest months. At the same time, majority of plantation crops are likely to benefit due to increase in rainfall during the post-monsoon season if they are stable and prolonged. 相似文献