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681.
The utilisation of Social Impact Assessment (SIA) in Iran is analysed in terms of its policy context and its application in practice. Five case studies where SIA was employed in conjunction with Environmental Impact Assessments (EIA) for agricultural development projects are evaluated. In addition, the performance of the policy context is assessed. This research revealed that there are legal and institutional constraints to the effective functioning of SIA in Iran, and that there are deficiencies in the operating guidelines. There were serious problems associated with the way SIA was undertaken in all five case studies. Recommendations to improve the policy framework for the conduct of SIA are made. The recommendations advocate for a higher profile of SIA within legislation, for social issues to have greater emphasis in official guidelines for the conduct of EIA and SIA, and for a range of measures to increase the professionalism of SIA practice.  相似文献   
682.
无线传感器网络在环境监测中的应用   总被引:5,自引:0,他引:5  
介绍了一种基于无线传感器网络的环境监测系统组成及架构,讨论了系统网络节点、网关的硬件设计,并对基于TinyOS的应用程序组件结构和节点工作流程做了说明。  相似文献   
683.
原子荧光光谱法同时测定环境水体中痕量锡和锌   总被引:2,自引:0,他引:2  
采用原子荧光光谱法同时测定环境水样中痕量锡和锌,优化了试验条件。锡在1.00μg/L~10.0μg/L、锌在20.0μg/L~200μg/L范围内线性良好,方法检出限锡为0.13μg/L,锌为1.76μg/L,锡和锌标准溶液测定的相对标准偏差分别为2.9%和4.0%,环境水样加标回收率锡为96.4%~106%,锌为92.0%~111%。  相似文献   
684.
浊点萃取分离富集荧光光度法测定水中α - 萘酚   总被引:2,自引:1,他引:1  
基于非离子表面活性剂Triton X-114,采用浊点萃取分离富集荧光光度法测定水中α-萘酚,优化了影响浊点萃取的各种因素,包括样品酸度、表面活性剂体积分数、氢氧化钠溶液浓度、平衡温度和时间等,讨论了常见无机离子和可能共存的有机物的干扰。方法在0.010 mg/L~0.400 mg/L范围内线性良好,检出限为3.0μg/L,标准溶液测定的RSD为4.8%,水样加标回收率为94.3%~103%。  相似文献   
685.
猛进水库是五家渠地区的主要水源地,也是乌鲁木齐市重要的淡水鱼供应基地.近年来,猛进水库水质呈不断恶化的趋势,水质为劣V类,为此,猛进水库水质恶化问题已经成为各级政府及公众十分关注的问题.本文选用新疆水环境监测中心多年对猛进水库水质监测及调查的资料,对猛进水库水质现状进行分析评价,运用季节性肯达尔(Kendall)检验等方法,分析了猛进水库水质变化趋势及影响猛进水库水质的主要污染源,提出了进一步保护猛进水库水质的建议,为改善其水环境质量提供依据.  相似文献   
686.
In this study, an interval-fuzzy two-stage chance-constrained integer programming (IFTCIP) method is developed for supporting environmental management under uncertainty. The IFTCIP improves upon the existing interval, fuzzy, and two-stage programming approaches by allowing uncertainties expressed as probability distributions, fuzzy sets, and discrete intervals to be directly incorporated within a general mixed integer linear programming framework. It has advantages in uncertainty reflection, policy investigation, risk assessment, and capacity-expansion analysis in comparison to the other optimization methods. Moreover, it can help examine the risk of violating system constraints and the associated consequences. The developed method is applied to the planning for facility expansion and waste-flow allocation within a municipal solid waste management system. Violations of capacity constraints are allowed under a range of significance levels, which reflects tradeoffs between the system cost and the constraint-violation risk. The results indicate that reasonable solutions for both binary and continuous variables have been generated under different risk levels. They are useful for generating desired decision alternatives with minimized system cost and constraint-violation risk under various environmental, economic, and system-reliability conditions. Generally, willingness to take a higher risk of constraint violation will guarantee a lower system cost; a strong desire to acquire a lower risk will run into a higher system cost.  相似文献   
687.
Mixed-integer linear programs are proposed for siting development and conservation areas in watersheds, addressing economic objectives (development perimeter and proximity) and ecological objectives. Links between watershed hydrology and ecology need not be well defined. Parameters for the linear programs are obtained from linearization of the SWAT hydrologic model.  相似文献   
688.
Rising populations and incomes throughout the world have boosted meat demand by over 75% in the last 20years, intensifying pressures on production systems and the natural resources to which they are linked. As a growing proportion of global meat production is traded, the environmental impacts of production become increasingly separated from where the meat is consumed. In this paper, we quantify the use of three important resources associated with industrial livestock production and trade—water, land, and nitrogen—using a country-specific model that combines trade, agronomic, biogeochemical, and hydrological data. Our model focuses on pigs and chickens, as these animals are raised predominantly in intensive systems using concentrated, compound feeds. The results describe the geographical patterns of environmental resource use due to meat production, trade, and consumption. We show that US feed, animal, and meat destined for export require almost as much nitrogen and land, and 20% more water, than products destined for domestic consumption. Model results also demonstrate that among various production factors, improvements in crop yields and animal feed conversion efficiencies result in the most significant reductions in environmental harm. By explicitly tracking the externalities of meat production, we hope to bolster suppliers’ accountability and provide better information to meat consumers.
Kirsten OlesonEmail:
  相似文献   
689.
2008年我国环境保护投资总体特征分析   总被引:1,自引:1,他引:0  
立足于环保投资数据库,从投资构成、空间分布和行业分布3个方面对我国环保投资进行综合分析。2008年,全国环保投资增幅持续保持较快增长,环保投资弹性系数为1.9,环保投资增速大大超过经济增速,"三同时"项目成为拉动环保投资的主要驱动力。引入了环保投资平衡度的概念,在此基础上对各地区环保投资的合理性进行了初步分析。重点行业环保投资方面,工业治污设施运行费用远远大于同期固定资产投资,一定程度上说明了应对治污运行费用来源给予充分重视,采取措施确保稳定可靠的资金渠道。  相似文献   
690.
The effect of selected organic and inorganic compounds, present in snow and cloudwater was studied. Photolysis of solutions of nitrate to nitrite was carried out in the laboratory using a UVB light source. The photolysis and other reactions were then modelled. It is shown that formate, formaldehyde, methanesulphonate, and chloride to a lesser extent, can increase the initial formation rate of nitrite. The effect, particularly significant for formate and formaldehyde, is unlikely to be caused by scavenging of hydroxyl radicals. The experimental data obtained in this work suggest that possible causes are the reduction of nitrogen dioxide and nitrate by radical species formed on photooxidation of the organic compounds. Hydroxyl scavenging by organic and inorganic compounds would not affect the initial formation rate of nitrite, but would protect it from oxidation, therefore, increasing the concentration values reached at long irradiation times. The described processes can be relevant to cloudwater and the quasi-liquid layer on the surface of ice and snow, considering that in the polar regions irradiated snow layers are important sources of nitrous acid to the atmosphere. Formate and (at a lesser extent) formaldehyde are the compounds that play the major role in the described processes of nitrite/nitrous acid photoformation by initial rate enhancement and hydroxyl scavenging.  相似文献   
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