基于模糊层次评价法的黄河兰州段突发水污染风险评价

为实现对流域突发水污染的分级管理,增加对水环境风险的应对能力,根据流域突发性水污染事故特点及风险形成机理,构建了以风险源危害性、控制机制有效性和风险受体易损性为准则层的风险评价指标体系,提出模糊层次综合评价法对流域突发水污染进行风险评价。以黄河兰州段为例对此模型进行应用,结果表明:兰州黄河流域内西固区、七里河区所处风险等级为Ⅱ级,属中度风险区;城关区风险等级为Ⅲ级,属低风险区;上游西固区工矿企业和城关区人口、水源地是研究段风险管理应着重关注的风险源和受体。

Risk assessment of sudden water pollution in Lanzhou section of Yellow River based on fuzzy hierarchy evaluation method

This article is aimed at proposing a quantitative method suitable for assessing the risk of sudden water pollution in Lanzhou section of the Yellow River basin so as to realize the graded management of such water pollution and enhance the power to deal with the risk accidents for water environment protection.And,just for this purpose,we have first of all built up the risk assessment index system of sudden water pollution suitable for watershed,with its steps being illustrated as follows:In regarding to the characteristic features of such water pollution accidents and the resulting mechanism of such accidental risks,it is essential to identify and determine the key indicative factors of the risk source hazards and overcome the vulnerability of the risk sufferers through the hierarchical analysis,and,then,categorize the said factors into a hierarchical structure in accordance with its interior attribution categories.Furthermore,it is also of practical need to bring into application the grading standards of each basic underlying indicator according to the currently existing standards and norms so as to determine the weight sets of indicators via the said hierarchical analysis and establish a fuzzy hierarchical evaluation model.And,finally,we have made trial application of the model to the pollution evaluation of the Lanzhou section of the River.The results of our practice show that the risk level of the Xigu District and Qilihe District can be relegated to grade Ⅱ,which should belong to the moderate risk zone.And,in comparison,the risk level of Chengguan District should be put to grade Ⅲ,that is,of the lower risk area.In spite of this,it is also of tremendous need to pay primary attention to the risk sources of the upstream pollution situation of the district and the risk sufferer of the district population and water source.Last of all,equal emphasis should also be put on the formulating of corresponding management measures according to the actual situation of the area under study and the leading risk factors.