基于组合权TOPSIS数学模型的 地表水水质评价

Evaluation of Surface Water Quality Based on Combined Weight-TOPSIS Mathematical Model

为了对超出Ⅴ类的水体进行评价,使水质评价更加客观全面,基于同里古镇8个断面的水质监测结果,将地表水水质标准划分为六级,引入主观赋权(AHP法)与客观赋权(熵权法)相结合确定的组合权重,采用组合权改进的TOPSIS数学模型对同里古镇水质进行评价,并与其他评价方法进行了对比。评价结果表明:采样监测期内同里古镇的水质为Ⅴ类或劣Ⅴ类,且古镇内部断面水质比外部断面更差;影响水质的主要因子为溶解氧(DO)和氨氮(NH 3-N)。组合赋权方法克服了单独采用主观赋权法或客观赋权法的缺点,赋权过程更加科学;组合权TOPSIS模型与改进模糊综合评价法结果基本一致,水质评价结果具有一定的区分度,值得在同类水质评价问题中推广应用。

In order to evaluate the water worse than class V,and make a more objective and comprehensive evaluation,based on the water quality monitoring results of 8 sections in old Tongli Town,this paper divides the surface water quality standards into six classes,determines the combined weight by the combination of subjective weighting(AHP)and objective weighting(entropy weight),evaluates the water quality of old Tongli Town by the TOPSIS mathematical model improved with combined weight,and compares the results with those of other methods.The evaluation results show that:The water quality of old Tongli Town is class V or V-,and the water quality of internal section is worse than that of external section.The main impact factors for water quality are the DO and NH 3-N.The combined weighting method overcomes the shortcoming of subjective weighting method or objective weighting method alone,with more scientific weighting process.The results of combined weight-TOPSIS model is basically consistent with those of the improved fuzzy comprehensive evaluation method,which can make the evaluation results more differentiated,so it is worthy of popularization and application in the evaluation of similar water quality.