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371.
This Φ Ψ study of environmental equity uses secondary quantitative data to analyze socioeconomic disparities in environmental
conditions in the Rijnmond region of the Netherlands. The disparities of selected environmental indicators—exposure to traffic
noise (road, rail, and air), NO2, external safety risks, and the availability of public green space—are analyzed both separately and in combination. Not only
exposures to environmental burdens (“bads”) were investigated, but also access to environmental benefits (“goods”). Additionally,
we held interviews and reviewed documents to grasp the mechanisms underlying the environmental equity situation, with an emphasis
on the role of public policy. Environmental equity is not a priority in public policy for the greater Rotterdam region known
as the Rijnmond region, yet environmental standards have been established to provide a minimum environmental quality to all
local residents. In general, environmental quality has improved in this region, and the accumulation of negative environmental
outcomes (“bads”) has been limited. However, environmental standards for road traffic noise and NO2 are being exceeded, probably because of the pressure on space and the traffic intensity. We found an association of environmental
“bads” with income for rail traffic noise and availability of public green space. In the absence of regulation, positive environmental
outcomes (“goods”) are mainly left up to market forces. Consequently, higher-income groups generally have more access to environmental
“goods” than lower-income groups. 相似文献
372.
An integrated fuzzy-stochastic modeling approach for risk assessment of groundwater contamination 总被引:7,自引:0,他引:7
An integrated fuzzy-stochastic risk assessment (IFSRA) approach was developed in this study to systematically quantify both probabilistic and fuzzy uncertainties associated with site conditions, environmental guidelines, and health impact criteria. The contaminant concentrations in groundwater predicted from a numerical model were associated with probabilistic uncertainties due to the randomness in modeling input parameters, while the consequences of contaminant concentrations violating relevant environmental quality guidelines and health evaluation criteria were linked with fuzzy uncertainties. The contaminant of interest in this study was xylene. The environmental quality guideline was divided into three different strictness categories: "loose", "medium" and "strict". The environmental-guideline-based risk (ER) and health risk (HR) due to xylene ingestion were systematically examined to obtain the general risk levels through a fuzzy rule base. The ER and HR risk levels were divided into five categories of "low", "low-to-medium", "medium", "medium-to-high" and "high", respectively. The general risk levels included six categories ranging from "low" to "very high". The fuzzy membership functions of the related fuzzy events and the fuzzy rule base were established based on a questionnaire survey. Thus the IFSRA integrated fuzzy logic, expert involvement, and stochastic simulation within a general framework. The robustness of the modeling processes was enhanced through the effective reflection of the two types of uncertainties as compared with the conventional risk assessment approaches. The developed IFSRA was applied to a petroleum-contaminated groundwater system in western Canada. Three scenarios with different environmental quality guidelines were analyzed, and reasonable results were obtained. The risk assessment approach developed in this study offers a unique tool for systematically quantifying various uncertainties in contaminated site management, and it also provides more realistic support for remediation-related decisions. 相似文献
373.
Rui Zhang Fan-Xin Zeng Wu-Jun Liu Raymond J. Zeng Hong Jiang 《Environmental management》2014,53(6):1119-1131
Environmental dredging is an efficient means to counteract the eutrophication of water bodies caused by endogenous release of nitrogen and/or phosphorus from polluted sediments. The huge operational cost and subsequent disposal cost of the dredged polluted sediments, as well as the adverse effect on the benthic environment caused by excessive dredging, make the currently adopted dredging methods unfavorable. Precise dredging, i.e., determining the dredging depth based on the pollution level, not only significantly decreases the costs but also leaves a uniform favorable environment for benthos. However, there is still no feasible process to make this promising method executable. Taking a river heavily polluted by organic compounds as an example, we proposed an executable precise dredging process, including sediment survey, model establishment, data interpolation, and calculation of dredging amount. Compared with the traditional dredging method, the precise one would save 16 to 45 % of cost according to different pollutant removal demands. This precise dredging method was adopted by the National Water Project of China to treat the endogenous pollution of Nanfei River in 2010. This research provides a universal scientific and engineering basis for sediment dredging projects. 相似文献
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马庄山金矿区位于星星峡一卡瓦布拉克地块、古生代岛弧东段北侧活动大陆边缘,有多种火山宕、次火山岩和侵入岩,而与金矿成矿关系最为密切的是海西中、晚期次火山岩。该矿区次火山岩有花岗闪长斑岩、石英斑岩、花岗斑岩、隐爆角砾岩(简称花岗质岩)和辉绿岩。因此,在区域地质背景和矿区地质特征分析基础上,着重对次火山岩及其地球化学特征进行系统研究,结果认为.该矿区花岗质岩为高硅富钾贫铝钙碱性同熔(1)型花岗岩类,岩浆源区来自中下地壳;辉绿岩则为富钠碱性正常型基性岩类,岩浆源区来自下地壳。前者含Co、Pb、Zn、Sn、As、Bi、W、Mo、An、Ag、Tc等元素较高,有重要找矿前景;后者含Ba、Pb、Zn、Tl、As、Bi、Au、Ag、Tc等元素较高,也可为成矿提供物源。这些认识,对该区次火山岩特征、性质、成矿关系和构造背景,以及进一步找矿都有重要理论和实践指导意义。 相似文献
377.
6月3日,国家环保模范城市市长峰会在人民大会堂隆重召开,中共中央政治局委员、国务院副总理曾培炎出席并作了重要讲话。本刊在此全文刊登讲话内容,以指导新时期的环境保护工作。 相似文献
378.
A new isolation procedure for the determination of nitrogen/phosphorous containing pesticides and organochlorine pesticides in water was tested, and statistical evaluation of the recoveries was performed. The procedure, designed specifically for the analysis of semi-volatile compounds in water containing Suspended Particulate Matter (SPM), utilizes a specially designed filtration vessel coupled directly to an SPE cartridge. The studies were based on surface water samples (from the Vistula River) spiked with pesticides. SPM separation and analyte isolation/concentration were carried out in a special filtration vessel. Pesticides were sorbed both on the SPE cartridge and on the suspended matter. The cartridge and the filter with the suspended matter were extracted separately with a solvent, which enabled the determination of analyte distribution between the two. For organochlorine pesticides, between 3 and 60% of the initial amount was found on the filter, while the recoveries in the filtrate ranged from 30 to 98%. Total recoveries of organochlorine pesticides from surface water samples spiked with pesticides using the method described were high, ranging from 90 to 101%. The amounts of nitrogen/phosphorus containing pesticides recovered from the filter were lower than 2%, while those from the filtrate ranged from 69 to 92%. Total recoveries of nitrogen/phosphorus containing pesticides from surface water samples were high, ranging from 71 to 92%. 相似文献
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The impact of wind turbulence-induced pressure fluctuations at the soil surface on landfill gas transport and emissions to the atmosphere at an old Danish landfill site was investigated using stochastic modelling combined with soil property and gas transport data measured at the site. The impacts of soil physical properties (including air permeability and volumetric water content) and wind-induced pressure fluctuation properties (amplitude and temporal correlation) on landfill gas emissions to the atmosphere were evaluated. Soil-air permeability and pressure fluctuation amplitude were found to be the most important parameters. Wind-induced gas emissions were further compared with gas emissions caused by diffusion and by long-term pressure variations (due to passing weather systems). Here diffusion and wind-induced gas transport were found to be equally important with wind-induced gas transport becoming the most important at lower soil-air contents. 相似文献