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11.
Environmental distribution conflicts (EDCs) related to the construction and operation of waste incinerators have become commonplace in China. This article presents a detailed case study of citizen opposition to an incinerator in the village of Panguanying, Hebei Province. Drawing on in-depth fieldwork, we show how this case was notable, because it transcended the local arena to raise bigger questions about environmental justice, particularly in relation to public participation in siting decisions, after villagers exposed fraudulent public consultation in the environmental impact assessment. An informal network between villagers and urban environmental activists formed, enabling the Panguanying case to exert influence far beyond the village locality. This network was critical in creating wider public debate about uneven power and substandard public participation in siting disputes, a central feature in many Chinese EDCs. By transcending local specificities and exposing broader, systemic inadequacies, this case became instrumental in supporting “strong sustainability”.  相似文献   
12.
Regional scale air quality simulation models covering spatial scales of thousands of kilometers are finding increasing applications in studies of acid deposition and other air pollution problems. The purpose of this paper is to familiarize the nonexpert with the characteristics of the major types of interregional air quality models currently in use: Eulerian grid, statistical trajectory, and Lagrangian trajectory. The basic features, advantages, and disadvantages of each of these modeling approaches are summarized, as are the important limitations and problems associated with interregional modeling in general. Typical applications are illustrated using examples from the use of a representative Lagrangian trajectory model, ENAMAP, over the eastern North American area.  相似文献   
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14.
The objective of the investigation of the municipal solid waste incinerator (MSWI) bottom ash landfill, Landfill Lostorf, was to determine the residence time of water in the landfill and the flow paths through the landfill. Over a period of 22 months, measurements of rainfall, landfill discharge and leachate electrical conductivity were recorded and tracer experiments made. Over the yearly period 1995, approximately 50% of the incident rainfall was measured in the discharge. An analysis of single rain events showed that in winter, 90–100% of rainfall was expressed in the landfill discharge, whereas in summer months, the value was between 9 and 40% depending on the intensity of the rain event. The response to rainfall was rapid. Within 30–100 h, approximately 50% of water discharged in response to a rain event had left the landfill. The discharge was less than 4 l/min for approximately 50% of the measurement periods. Qualitative tracer studies with fluorescein, pyranine and iodide clearly showed the existence of preferential flow paths. This was further substantiated by quantitative tracer studies of single rain events using / ratios and electrical conductivity measurements. The proportion of rainwater passing directly through the landfill was found to be between 20 and 80% in summer months and around 10% in winter months. The difference has been ascribed to the water content in the landfill. The average residence time of the water within the landfill has been estimated to be roughly 3 years and this water is the predominant component in the discharge over a yearly period.  相似文献   
15.
Concentrations of air pollutants were monitored during the May November 1999 period on a network of forested sites in Sequoia National Park, California. Measurements were conducted with: (1) active monitors for nitric oxide (NO), nitrogen dioxide (NO2) and ozone (O3); (2) honeycomb denuder/filter pack systems for nitric acid vapor (HNO3), nitrous acid vapor (HNO2), ammonia (NH3), sulfur dioxide (SO2), particulate nitrate (NO3-), ammonium (NH4+), and sulfate (SO4(2-)); and (3) passive samplers for O3, HNO3 and NO2. Elevated concentrations of O3 (seasonal means 41-71 ppb), HNO3 (seasonal means 0.4-2.9 microg/m3), NH3 (seasonal means 1.6-4.5 microg/m3), NO3 (1.1-2.0 microg/m3) and NH4+ (1.0-1.9 microg/m3) were determined. Concentrations of other pollutants were low. With increasing elevation and distance from the pollution source area of O3, NH3 and HNO3 concentrations decreased. Ammonia and NH4+ were dominant N pollutants indicating strong influence of agricultural emissions on forests and other ecosystems of the Sequoia National Park.  相似文献   
16.
Agricultural opportunities to mitigate greenhouse gas emissions   总被引:15,自引:0,他引:15  
Agriculture is a source for three primary greenhouse gases (GHGs): CO(2), CH(4), and N(2)O. It can also be a sink for CO(2) through C sequestration into biomass products and soil organic matter. We summarized the literature on GHG emissions and C sequestration, providing a perspective on how agriculture can reduce its GHG burden and how it can help to mitigate GHG emissions through conservation measures. Impacts of agricultural practices and systems on GHG emission are reviewed and potential trade-offs among potential mitigation options are discussed. Conservation practices that help prevent soil erosion, may also sequester soil C and enhance CH(4) consumption. Managing N to match crop needs can reduce N(2)O emission and avoid adverse impacts on water quality. Manipulating animal diet and manure management can reduce CH(4) and N(2)O emission from animal agriculture. All segments of agriculture have management options that can reduce agriculture's environmental footprint.  相似文献   
17.
Sediments contaminated by various sources of mercury (Hg) were studied at 8 sites in Sweden covering wide ranges of climate, salinity, and sediment types. At all sites, biota (plankton, sediment living organisms, and fish) showed enhanced concentrations of Hg relative to corresponding organisms at nearby reference sites. The key process determining the risk at these sites is the net transformation of inorganic Hg to the highly toxic and bioavailable methylmercury (MeHg). Accordingly, Hg concentrations in Perca fluviatilis were more strongly correlated to MeHg (p < 0.05) than to inorganic Hg concentrations in the sediments. At all sites, except one, concentrations of inorganic Hg (2-55 microg g(-1)) in sediments were significantly, positively correlated to the concentration of MeHg (4-90 ng g(-1)). The MeHg/Hg ratio (which is assumed to reflect the net production of MeHg normalized to the Hg concentration) varied widely among sites. The highest MeHg/Hg ratios were encountered in loose-fiber sediments situated in southern freshwaters, and the lowest ratios were found in brackish-water sediments and firm, minerogenic sediments at the northernmost freshwater site. This pattern may be explained by an increased MeHg production by methylating bacteria with increasing temperature, availability of energy-rich organic matter (which is correlated with primary production), and availability of neutral Hg sulfides in the sediment pore waters. These factors therefore need to be considered when the risk associated with Hg-contaminated sediments is assessed.  相似文献   
18.
PROBLEM: Injuries resulting from lifting are costly, and create significant pain and discomfort. While engineering controls are the most effective means of reducing risks, most organizations continue to rely on manual lifting techniques. The problem, however, is that the use of safe-lifting techniques is inconsistent and managers have a difficult time motivating use of these techniques. Consequently, it is important to understand the factors driving safe-lifting behaviors. METHODS: This study used a survey to apply the theory of planned behavior (Ajzen., I., 1991. The theory of planned behavior. Organization Behavior and Human Processes, 50, 179-211) to safe-lifting among 136 materials management employees at a heavy manufacturing organization. Structural equation modeling and factor analysis were employed to analyze relationships among constructs. RESULTS: Results revealed that perceived behavioral control and intention were the strongest predictors of safe-lifting behavior. Subjective norms, to a lesser degree, were also important influences on intention. Attitudes did not surface as effective direct predictors of safe-lifting behavior, but did affect behavior and intent via mediating factors (subjective norms and perceived behavioral control). Finally, the theory of planned behavior was supported as an effective model explaining safe-lifting behavior, and had potential application for many other safety-related behaviors. IMPACT ON INDUSTRY: Results from this study emphasize the importance of perceived behavioral control as a factor associated with safety-related behavior.  相似文献   
19.
Promoting shared leadership in teams and enhancing team creativity is aided by complementarity between leader and team member characteristics. We integrate insights from social learning theory and dominance complementarity perspective with the team leadership and creativity literature to explore the facilitating role of formal participative leadership for enhancing team creativity indirectly by promoting shared leadership. The relationships among formal participative leadership, shared leadership, and team creativity are bounded by team voice behavior and team creative efficacy. To test our theoretical model, we collected multisource and multiwave survey data from 382 members of 73 teams. Results revealed a significant positive relationship of participative leadership with shared leadership in teams, which in turn was positively associated with team creativity. Team voice behavior and team creative efficacy moderated these relationships, respectively, by strengthening the positive relationships. We discuss the theoretical contributions, practical implications, and future directions of our findings.  相似文献   
20.
The impact of co-solutes on sorption of tetrachloroethene (PCE) by two porous media with low organic-carbon contents was examined by conducting batch experiments. The two media (Borden and Eustis) have similar physical properties, but significantly different organic-carbon (OC) contents. Sorption of PCE was nonlinear for both media, and well-described by the Freundlich equation. For the Borden aquifer material (OC = 0.03%), the isotherms measured with a suite of co-solutes present (1,2-dichlorobenzene, bromoform, carbon tetrachloride, and hexachloroethane) were identical to the isotherms measured for PCE alone. These results indicate that there was no measurable impact of the co-solutes on PCE sorption for this system. In contrast to the Borden results, there was a measurable reduction in sorption of PCE by the Eustis soil (OC = 0.38%) in the presence of the co-solutes. The organic-carbon fractions of both media contain hard-carbon components, which have been associated with the manifestation of nonideal sorption phenomena. The disparity in results observed for the two media may relate to relative differences in the magnitude and geochemical nature of these hard-carbon components.  相似文献   
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