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1.
/ Why are some environmental risks distributed disproportionately in the neighborhoods of the minorities and the poor? A hypothesis was proposed in a recent study that market dynamics contributed to the current environmental inequity. That is, locally unwanted land uses (LULUs) make the host communities home to more poor people and people of color. This hypothesis was allegedly supported by a Houston case study, whereby its author analyzed the postsiting changes of the socioeconomic characteristics of the neighborhoods surrounding solid waste facilities. I argue that such an analysis of postsiting changes alone is insufficient to test the causation hypothesis. Instead, I propose a conceptual framework for analysis of environmental equity dynamics and causation. I suggest that the presiting neighborhood dynamics and the characteristics of control neighborhoods be analyzed as the first test for the causation hypothesis. Furthermore, I present theories of neighborhood change and then examine alternative hypotheses that these theories offer for explaining neighborhood changes and for the roles of LULUs in neighborhood changes. These alternative hypotheses should be examined when analyzing the relationship between LULUs and neighborhood changes in a metropolitan area. Using this framework of analysis, I revisited the Houston case. First, I found no evidence that provided support for the hypothesis that the presence of LULUs made the neighborhoods home to more blacks and poor people, contrary to the conclusion made by the previous study. Second, I examined alternative hypotheses for explaining neighborhood changes-invasion-succession, other push forces, and neighborhood life-cycle; the former two might offer better explanation.KEY WORDS: Environmental equity and justice; Locally unwanted lane uses; Siting; Market dynamics; Invasion-succession; Neighborhood changes  相似文献   
2.
ABSTRACT

Interaction of environmental pollution between peripheral areas has become a central topic in the field of resources and environment but little is known about the actual impact on peripheral areas in the current literature. This paper sets out a simultaneous equation model to investigate the spillover effect of environmental pollution between China’s peripheral areas utilizing the panel data of 218 cities in China. Making use of indicators for measuring the impact on environmental pollution, it identifies that environmental pollution between cities of China has a significant two-way spillover effect. After standardization of variables, it is found that the spillover effect of peripheral areas on urban environmental pollution cannot be neglected. Nearly, a third of the environmental pollution level in a city is induced by the environmental pollution in peripheral areas. If the indicator of environmental pollution in peripheral areas is missing, wrong conclusions will be drawn. Therefore, government should shift the emphasis of environmental regulation from local to global, and improve the overall environmental quality through coordinated management of regional environment.  相似文献   
3.
Red meat production has a range of negative environmental impacts. We sought to characterize the motivations, environmental attitudes and demographics of red meat-eaters, and examine the effect of message framing in reducing future meat consumption. Canadian adult meat-eaters (593) completed a survey and were randomly assigned to one of six message treatments that presented information on the environmental impacts of meat production using frames representing social norms and/or place identity constructs. Taste and quality were the most important motivators for eating meat, while moral/ethical factors were the least. Forty-nine percent of respondents indicated they would reduce red meat intake after exposure to an information only message, while the social norms frame was more effective than others (χ2). Awareness of the environmental effects increased significantly after messaging for all 13 impacts. These findings should assist communicators with designing more effective messaging aimed at encouraging pro-environmental behaviours associated with meat consumption.  相似文献   
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5.
根据对各级环保机械综合信息技术应用的调研,提出环境监测综合信息系统设计原则及技术路线。  相似文献   
6.
畜禽养殖污染是不容忽视的新的环境问题   总被引:5,自引:0,他引:5  
本文论述了畜禽养殖业对环境带来的污染已成为新的环境问题,并提出了改进的措施。  相似文献   
7.
On exposure to sunlight or photolysis at λ >300nm, the dechlorination of a polychlorinated biphenyl mixture (Aroclor 1254) in the H donor alcohol 2-propanol under neutral conditions is enhanced by the presence of the photosensitizer hydroquinone. Dechlorination is strongly promoted by an increasingly aqueous solvent (1:1 water:alcohol) and by maintaining neutral conditions (pH 7.0 buffer) both in the presence and absence of sensitizer. Atmospheric oxygen (continuous aeration) retards the hydroquinone induced dechlorination less than the direct photolysis process.  相似文献   
8.
Lepom P  Irmer U  Wellmitz J 《Chemosphere》2012,86(2):202-211
Mercury concentrations have been analysed in bream (Abramis brama L.) and zebra mussels (Dreissena polymorpha) collected at 17 freshwater sites in Germany from 1993-2009 and 1994-2009, respectively, within the German Environmental Specimen programme. Mercury concentrations in bream ranged from 21 to 881 ng g−1 wet weight with lowest concentrations found at the reference site Lake Belau and highest in fish from the river Elbe and its tributaries. Statistical analysis revealed site-specific differences and significant decreasing temporal trends in mercury concentrations at most of the sampling sites. The decrease in mercury levels in bream was most pronounced in fish from the river Elbe and its tributary Mulde, while in fish from the river Saale mercury levels increased. Temporal trends seem to level off in recent years. Mercury concentrations in zebra mussels were much lower than those in bream according to their lower trophic position and varied by one order of magnitude from 4.1 to 42 ng g−1 wet weight (33-336 ng g−1 dry weight). For zebra mussels, trend analyses were performed for seven sampling sites at the rivers Saar and Elbe of which three showed significant downward trends. There was a significant correlation of the geometric mean concentrations in bream and zebra mussel over the entire study period at each sampling site (Pearson’s correlation coefficient = 0.892, p = 0.00002). A comparison of the concentrations in bream with the environmental quality standard (EQS) of 20 ng g−1 wet weight set for mercury in biota by the EU showed that not a single result was in compliance with this limit value, not even those from the reference site. Current mercury levels in bream from German rivers exceed the EQS by a factor 4.5-20. Thus, piscivorous top predators are still at risk of secondary poisoning by mercury exposure via the food chain. It was suggested focusing monitoring of mercury in forage fish (trophic level 3 or 4) for compliance checking with the EQS for biota and considering the age dependency of mercury concentrations in fish in the monitoring strategy.  相似文献   
9.
Wu Q  Qu Y  Li X  Wang D 《Chemosphere》2012,87(11):1281-1287
Here we investigated whether the assay system (10-d) in Caenorhabditis elegans can be used to evaluate chronic toxicity of chromium (Cr(VI)) at environmental relevant concentrations ranging from 5.2 μg L−1 to 260 μg L−1. The results indicated that lethality, locomotion behavior as revealed by head thrash, body bend, and forward turn, metabolism as revealed by pumping rate and mean defecation cycle length, intestinal autofluorescence, and ROS production were severely altered in Cr chronically exposed nematodes at environmental relevant concentrations. The most surprising observations were that head thrash, body bend, intestinal autofluorescence, and ROS production in 13 μg L−1 Cr exposed nematodes were significantly influenced. The observed adverse effects of Cr on survival, locomotion behavior, and metabolism were largely due to forming severe intestinal autofluorescence and ROS production. Therefore, our findings demonstrate the usefulness of chronic toxicity assay system in C. elegans in evaluating the chronic toxicity of toxicants at environmental relevant concentrations.  相似文献   
10.
We report results of a multigenerational experiment with Chironomus riparius. Two strains with a high and a low level of genetic variability were exposed to a low, environmentally relevant TBT concentration of 80 μg Sn kg−1 sediment dw nominally (time weighted mean, based on measured concentrations: 4.5 μg Sn kg−1 sediment dw), and various life history traits as well as genetic diversity were monitored for eleven consecutive generations. While TBT effects are hardly visible in the outbred and genetically diverse strain, the inbred and genetically impoverished strain shows a clearly reduced population growth rate compared to the control. Moreover, the impoverished strain shows an increase in fitness over time. Analyses of variation at five microsatellite loci revealed that the level of genetic variation is strongly reduced in the inbred compared to the outbred strain. Moreover, genetic diversity increases over time in the inbred strain. This finding explains the observed increase in fitness in both inbred lineages (control and TBT exposed). The results document that inbreeding and the level of genetic diversity might be of crucial importance in populations under pollution stress. Furthermore, ecotoxicological bioassays have to consider genetic diversity if results between laboratories should be comparable. Our data provides evidence that genetic diversity strongly contributes to the survival of a population exposed to chemical pollution.  相似文献   
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