基于层次分析与集对理论的城市污染场地风险等级划分

城市污染场地风险评价过程充满不确定性因素,其中评价系统的客观随机性、评价因子选取的不完整以及监测数据的不精确都易导致评价结果失真,不能客观反映场地的实际风险情况。在综合考虑场地污染带来的潜在生态风险和人体健康风险的基础上,本文将递阶分层的评价指标体系用于场地污染风险分级,采用层次分析法确定了各层各指标的权重;并用模糊聚类思想建立了评价指标集,同时对综合评价指标进行量化,根据对综合评价指标的取值研究,将污染场地风险等级划分为低、中、较重、重和严重5类;构建了一个基于不确定信息的场地污染风险集对分析模型。实例验证表明,集对分析法与模糊综合评价法评价结果基本一致,评价手段合理,为场地污染风险等级划分提供了一种新方法。

URBAN CONTAMINATED SITES RISK CLASSIFICATION BASED ON THE ANALYTIC HIERARCHY PROCESS AND SET PAIR ANALYSIS

Urban contaminated sites risk assessment process is full of uncertainties,of which,the objective randomness of the system,the incompleteness of selected evaluation factors and the inaccuracy of the data may lead to the evaluation results distortion and can not objectively reflect the actual risk situation of the site.A hierarchical stratification contaminated sites risk assessment system is established based on the consideration of potential ecological risk and human health risk caused by contaminated sites,and analytic hierarchy process(AHP) is applied to calculate the weight of the index of the layers.With the ideological of fuzzy clustering,an evaluation index set is established,meanwhile,the comprehensive evaluation indexes are quantified.According to the comprehensive evaluation index values,the risk level of contaminated site is divided into five levels of "low","medium","heavy","heavier" and "very-heavy".A set pair analysis(SPA) model is developed to describe the contaminated site risk based on the uncertain information.Verified by an example,the results show that evaluation results are basically the same using the SPA compared to fuzzy comprehensive evaluation method.The result is reasonable and provides a new method for contaminated sites division of the level of risk.