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871.
This paper reports the distribution of Polycyclic Aromatic Hydrocarbons (PAHs) in wash-off in urban stormwater in Gold Coast, Australia. Runoff samples collected from residential, industrial and commercial sites were separated into a dissolved fraction (<0.45 μm), and three particulate fractions (0.45-75 μm, 75-150 μm and >150 μm). Patterns in the distribution of PAHs in the fractions were investigated using Principal Component Analysis. Regardless of the land use and particle size fraction characteristics, the presence of organic carbon plays a dominant role in the distribution of PAHs. The PAHs concentrations were also found to decrease with rainfall duration. Generally, the 1- and 2-year average recurrence interval rainfall events were associated with the majority of the PAHs and the wash-off was a source limiting process. In the context of stormwater quality mitigation, targeting the initial part of the rainfall event is the most effective treatment strategy. The implications of the study results for urban stormwater quality management are also discussed.  相似文献   
872.
以太湖15个入湖河流之一的社渎港为研究对象,利用社渎港流域的水环境质量监测数据、工业企业污染排放调查数据、环境统计数据及社会经济统计数据,对社渎港流域产业结构的合理性进行了诊断,并采用典型相关分析方法探讨了产业结构演变对水环境的影响。结果表明,研究区的工业污染总体上得到了较好控制,其中屺亭街道的工业污染排放最为严重;城乡生活污染和农业面源污染是研究区水环境质量恶化的主要原因,城乡生活污染对COD和氨氮入河量的贡献率较高,分别为46.59%和60.55%,农业面源污染对TN和TP入河量的贡献率突出,分别为64.05%和76.50%;研究区产业结构与钱纳里三次产业结构模式(产业结构合理程度的参照标准)的Hamming贴近度从2001年的0.83下降到2007年的0.77,产业结构不尽合理,且不合理程度逐渐加剧;研究区第一产业对TN和TP入河量的影响最为显著,第三产业对氨氮和COD入河量的影响最为明显;可通过优化产业结构来减轻研究区的水环境污染状况,产业结构调整的主要目标应为降低第二产业产值比例及增加第三产业产值比例。  相似文献   
873.
不同模糊评价方法在水环境质量评价中的应用比较   总被引:7,自引:0,他引:7  
近年来,运用模糊评价方法对水质和水体营养化程度进行评价逐渐受到重视。目前,对模糊评价方法的研究多集中在实测数据标准化、权重的确定和模糊模式识别模型研究几个方面。以滇池历年营养物质数据为实测数据,通过对几种实测数据标准化方法、权重确定方法和模糊模式识别方法的组合应用,获得水环境质量模糊评价最优组合方法。结果表明,在评价方法中,实测数据标准化方法采用线性内插法,权重的确定采用超标倍数法,模糊模式识别模型采用广义海明距离和加权海明距离法,即采用超标倍数法的广义海明距离和加权海明距离法能够更真实反映水环境质量的实际情况。  相似文献   
874.
吐曼河近5a水质变化浅析   总被引:1,自引:0,他引:1  
通过单因子评价法对吐曼河水质现状及近期变化趋势进行了分析,揭示了近几年来吐曼河水质年内及年际变化的特点,以期对吐曼河水污染治理提供参考。  相似文献   
875.
秦皇岛市天然矿泉水水质特征及开发利用前景研究   总被引:2,自引:0,他引:2  
秦皇岛市天然矿泉水主要赋存在早太古代的花岗岩和变质岩的构造裂隙与风化裂隙之中,有锶、偏硅酸、锶及偏硅酸、锶溴及偏硅酸等4种类型。矿泉水水源地数量较多,水质优良,但开采程度较低,开发利用前景广阔。  相似文献   
876.
Zardari, Noor ul Hassan, Ian Cordery, and Ashish Sharma, 2010. An Objective Multiattribute Analysis Approach for Allocation of Scarce Irrigation Water Resources. Journal of the American Water Resources Association (JAWRA) 46(2):412-428. DOI: 10.1111/j.1752-1688.2009.00410.x Abstract: In this study, end user (farmer) and decision maker (water allocator) opinions were surveyed and a conjoint analysis (CA) based method was applied to the quantitative and qualitative data to assess the utility associated with each attribute that plays a role in forming the final thinking of the water users. The application of CA for estimating the utility for each attribute level is a novel approach, which helps provide a formal, objective basis for assigning relative scales for each attribute interval within a multiattribute decision-making model. The utilities (part-worths) obtained from the CA have a cardinal scale and were found to be comparable within and across the attributes. A farmers’ survey on five water allocation attributes was completed from 62 farmers and their opinions on the relative importance of attributes were elicited for a subarea of the Indus River Basin. The CA method was then applied to the survey data and the utilities for each attribute level were determined. This allowed, for instance, decisions to be made, which take account of the perceived value of the water and of the availability of local labor to work on the farm. Finally, these interval scales were used within the specification of the ELECTRE multiattribute decision-making method to provide a complete and objective ranking of nine irrigation districts so that the best decisions on water allocation could be made.  相似文献   
877.
对南京市在污染源普查过程中采取的质控措施进行了探讨,分析出普查质控工作的不足,并提出了几点建议。为提高以后普查的质量拓宽思路。  相似文献   
878.
从环境监测为环境管理服务的职能入手,系统分析了基层环境监测站的环境质量综合分析工作现状,针对实际工作中存在的问题,提出了提高环境质量综合分析水平的对策建议。  相似文献   
879.
River Nile is one of the longest transboundery rivers and it is shared and used by Burundi,Democratic Republic of Congo,Egypt,Ethiopia,Eritrea,Kenya,Rwanda,Sudan,Tanzania and Uganda.As of today,the Nile is a crucial resource for the economic development of the Nile Basin countries and a vital source of livelihood for 160 million inhabitants as well as 300 million people living in the 10 riparian countries.The Nile Basin Initiative(NBI) is one of the international cooperative river basin management program and regional partnership where all the Nile Basin countries except Eritrea unite to pursue long-term sustainable development,improved land use practices and management.This review therefore focused on the challenges not faced on NBI in terms of integrated use of the river and conducted analysis of strengths,weaknesses,opportunities and threats(SWOT) based on secondary data.The result of the review revealed that for decades,the Nile Basin people have been facing many complex environmental,social,economic and political challenges that have made it difficult for the proper management and sustainability of Nile water.The initiative provides training to develop skills in government ministries,non-governmental organizations and local communities in each country.It is also working to raise awareness of critical environmental issues by strengthening networks of environmental education practitioners;developing curriculum in the education sector.The challenges of NBI include the involvement and funding of World Bank,lack of sufficient staff,procedural and policies conflicts,lack of coordination and linkage with other regional institutions and lack of recognition as river basin organization.Considering the complex nature of the project,it is recommended that the NBI should come up with a strong multi-disciplinary monitoring and evaluation team to follow up all implemented projects.The NBI should carry out participatory land use planning in communities along the river basin.Moreover,livelihood analysis should be carried out especially in communities along the Nile to come up with poverty eradication projects which are socially acceptable,applicable,economically viable and affordable.  相似文献   
880.
利用模糊数学方法,根据元素毒性的大小进行权重赋值,对成都经济区近地表大气尘进行地球化学环境质量评价。结果显示:不同城市中,成都、乐山、眉山的大气环境质量较好,处于一级清洁级别;眉山、雅安的大气环境质量处于二级安全级别;德阳的大气环境质量已经处于三级警戒级。不同地区中,绵阳和眉山的大气环境质量较好,处于一级清洁级别;德阳和雅安处于二级安全级别,成都和乐山处于三级警戒级.  相似文献   
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