层次化健康风险评估方法在苯污染场地的应用及效益评估

以北京某大型苯污染场地为例,详细介绍了如何开展层次化健康风险评估.同时,结合场地污染调查结果,比较了不同层次风险评价确定的土壤苯修复目标、修复量及修复成本的差异.结果表明,在1×10-6可接受致癌风险水平下,该场地第二层次风险评价确定的0～1.5 m深度范围内土壤苯修复目标为0.26 mg·kg-1、1.5～10 m范围内土壤苯修复目标为0.15mg·kg-1,相应的土壤修复量约为292 759 m3,修复成本约2.06亿元.但是,基于该场地苯污染区域土壤气中苯浓度进行的第三层次风险评价确定的0～1.5 m深度范围内土壤苯修复目标为2.6 mg·kg-1、1.5～10 m范围内土壤苯修复目标为1.5mg·kg-1,相应的土壤修复量约为153 222 m3,减少139 537 m3,修复成本为1.49亿元,减少了5 700万元,修复成本的降低远多于因开展第三层次风险评价所付出的约10万元的成本.因此,对于类似大型VOCs污染场地,开采第三层次健康风险评价能够节省大量修复成本、带来巨大的经济效益.     

中水回用与效益分析

当前我国水资源供需矛盾日益加剧,实现中水利用是节约水资源的一条有效途径.通过分析中水水源、MBR处理技术及中水用途,结合一个高校实例,进行经济效益分析,并对建设中水回用系统的可行性进行论证.经计算可得效益费用比达到2.38,经济效益是非常明显的,具有实际的参考价值.中水回用不仅节约了水资源而且也产生了明显的经济效益,是城市发展的趋势.     

Review on water leakage control in distribution networks and the associated environmental benefits

Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water is lost from the pipes of distribution systems. Water leakage is not only a waste of water resources, but also incurs great socio-economic costs. This article presents a comprehensive review on the potential water leakage control approaches and specifically discusses the benefits of each to environmental conservation. It is concluded that water leakage could be further reduced by improving leakage detection capability through a combination of predictive modeling and monitoring instruments, optimizing pipe maintenance strategy, and developing an instant pressure regulation system. The environment could benefit from these actions because of water savings and the reduction of energy consumption as well as greenhouse gas emissions.     

滇池污染底泥环保疏浚一期工程实施后环境效益评估

通过对滇池草海污染底泥环保疏浚一期工程实施前后水质、底质及水生生物的监测和分析,评价工程实施后对改善草海水质,减轻内源负荷及对水生态恢复的环境效益。结果表明,疏浚工程直接去除了草海污染底泥层,随污染层分别去除TN、TP20 538 t和1 716 t。疏浚后草海水体透明度由0.37 m提高到0.80 m,水体中的TN和TP由疏挖前的8.91 mg/L和1.07 mg/L降低到疏挖后的8.15 mg/L和0.69 mg/L。疏浚后新生界面层促使形成新的水—沉积物的平衡,水质与底质条件改善以及水下光照条件超过沉水植物恢复的需求,是疏浚后水生态呈现恢复趋势的机理。     

Female seed beetles, <Emphasis Type="Italic">Callosobruchus maculatus,</Emphasis> remate for male-supplied water rather than ejaculate nutrition

Female seed beetles, Callosobruchus maculatus, mate multiply even though association with males and copulations carry costs, such as injury to the genital tract. Multiple mating (polyandry) may, however, offset these costs through the acquisition of food and water, two material benefits hypothesized to be obtained from the large ejaculates produced by males. The material benefits hypothesis can be tested by increasing female access to nutrients and water, with the prediction that female mating frequency will decrease as copulation is no longer required to derive these materials. Females were given water, 5% sugar–water or baker’s yeast, and were compared with females deprived of these. We presented females with virgin males daily for 8 days and recorded female mating frequency, survivorship, and fecundity. Females provided with water and sugar–water decreased mating frequency. Thus, water, rather than nutrients in the ejaculate, appears to be important to females of this species. In addition, both life span and fecundity were extended for females in the sugar–water and water treatments. Since water is scarce in the arid environment in which this species is found, we conclude that polyandry provides material benefits to females that may offset some of the costs of associating with males.     

运用LCA方法分析污水再生处理的成本效益

运用生命周期评价(LCA)方法,以西安市北石桥污水净化中心的污水处理与再生利用全过程为例进行环境影响评价,通过清单分析、当量计算和权重分析等一系列分析过程,计算出污水处理过程的投入成本及污水再生处理前后对环境的影响,得出污水在经过处理后,能够很大程度上减小其对环境的影响,从而产生环境正效益。该研究明确了污水处理在环境保护中的重要地位,同时对优化污水处理与再生利用工艺过程具有重要的参考价值和指导意义。     

Health benefits valuation of regulatory intervention for air pollution control in thermal power plants in Delhi,India

This study estimates minimum marginal health benefits (morbidity reduction only) of air pollution control and total health benefits arising from regulatory intervention regarding the adoption of the World Bank emission guidelines (WBEG) for thermal power plants (TPPs) in Delhi. The Industrial Source Complex-Short-Term Version–3 (ISCST3) model has been used to estimate the contribution to air pollution from TPPs. The household health production function (avertive behaviour) has been used to value health benefits of air pollution control. The study revealed that the ambient air pollution due to TPPs is reduced by between 62.17% to 83.45% by adopting the WBEG. Annual marginal benefit due to reduction in exposure to air pollution by 1 μg m^?3 is estimated to be US$0.353 per person. Total annual health benefits for adopting the WBEG for TPPs are estimated at US$235.19 million. This study provides a novel methodology to evaluate health benefits of regulatory intervention.     

ESTIMATION OF POTENTIAL REDUCTIONS IN RECREATIONAL BENEFITS DUE TO SEDIMENTATION1

ABSTRACT: A travel cost model is developed to estimate the potential reductions in recreational benefits from sedimentation in Reelfoot Lake in northwestern Tennessee. In addition to the consumer surplus estimates generated by the model, three other aspects of the study were significant. First, the study applied a relatively untested methodology for deriving the opportunity cost of travel time. The study resulted in a value that is less than one-half of the Water Resource Council's “one-third of the wage rate” rule-of-thumb. Second, water quality perceptions were unsuccessfully incorporated into the model as a demand shifter. This raised questions as to the appropriate manner in which perceptions could be included in a travel cost model. Finally, a simple methodology was outlined by which estimates of the recreational value of Reelfoot Lake could be used to suggest how much cost could be justified for soil erosion control on agricultural land surrounding the lake.     

ESTIMATING THE WATER QUALITY BENEFITS FROM SOIL EROSION CONTROL1

ABSTRACT: A framework for estimating the water quality benefits from soil erosion was developed. The framework is based on the linkages between soil erosion and offsite damages. The linkages are: erosion on the field, movement of eroded materials to waterways, impact of discharged material on water quality parameters, impact of water quality changes on ability of water to provide economic services, and the economic value of the changes in water use. These linkages need to be modeled in order to estimate the water quality benefits from reductions in soil erosion. Methods for modeling each link on a geographic level, which enables the analyses of national soil conservation, were examined. Areas where data or models were found to be lacking include transport of sediment and nutrients to water systems, impact of discharged materials on water quality parameters, and impact of water quality on ability of water to provide economic services. An economic evaluation of 1983 soil conservation programs was presented as an example of how the framework could be used. A number of simplifying assumptions were made to represent links that could not be modeled with available data.     

Drainage Investment and Wetlands Loss: an Analysis of the National Resources Inventory Data

The United States Soil Conservation Service (SCS) conducts a survey for the purpose of establishing an agricultural land use database. This survey is called the National Resources Inventory (NRI) database. The complex NRI land classification system, in conjunction with the quantitative information gathered by the survey, has numerous applications. The current paper uses the wetland area data gathered by the NRI in 1982 and 1987 to examine empirically the factors that generate wetland loss in the United States. The cross-section regression models listed here use the quantity of wetlands, the stock of drainage capital, the realty value of farmland and drainage costs to explain most of the cross-state variation in wetland loss rates. Wetlands preservation efforts by federal agencies assume that pecuniary economic factors play a decisive role in wetland drainage. The empirical models tested in the present paper validate this assumption.