熵权扩展集对分析模型在西安市浅层地下水水质评价中的应用

Application of Entropy Weight Extended Set Pair Analysis Model on Xi'an City Shallow Groundwater Quality Assessment

为克服地下水水质评价传统方法的不足,为西安市地下水环境的保护和治理提供依据,应用熵权扩展集对分析模型对西安市浅层地下水水质进行评价。选取一般化学指标8项,毒理学指标3项作为地下水水质评价因子,采用熵权法确定各评价指标权重,将集对分析模型由以往的3元扩展为5元,对19口监测井水质进行评价。结果表明:研究区单井水质可划分为四个级别,其中测井12#、4#水质优,水质级别Ⅱ级;7#、1#、2#、19#、3#、10#、13#水质良好,水质级别Ⅲ级;6#、8#、5#、15#、16#、11#水质中等,水质级别为Ⅳ级;17#、18#、9#、14#水质较差,水质级别为Ⅴ级。将西安市浅层地下水划分为3级4个水质分区,包括长安区、周至县、鄠邑区水质优良区;灞桥区、未央区水质优良区;鄠邑—长安—蓝田以北,渭河以南水质中等区;临潼区、阎良区、高陵县水质较差区。

To overcome the deficiency in traditional groundwater quality assessment methods,the entropy weight extended set pair analysis model has been used on the Xi’an City shallow groundwater quality assessment to provide basis for groundwater environment protection and governance.Totally 8 general chemical indices and 3 toxicological indices have been selected as groundwater quality assessment factors,through entropy weight method to define weight for each index;then extended the set pair analysis form original 3 elements to 5 elements carried out water quality assessment for 19 monitoring wells.The result has shown that the single well water quality in the study area can be partitioned into 4 categories.In which,well Nos.12 and 4 have excellent water quality,belong to category II;Nos.7,1,2,19,3,10 and 13 water quality good,belong to category III;Nos.6,8,5,15,16 and 11 water quality medium,belong to category IV;Nos.17,18,9 and 14 water quality poor,belong to category V.The shallow groundwater in Xi’an City can be partitioned into 3 grades and 4 zones:they are 1).Chang’an District,Zhouzhi County and Huyi District water quality good zone;2)Baqiao and Weiyang districts water quality good zone;3)to the north of Huyi-Chang’an-Lantian line,south of the Weihe River water quality medium zone;4)Lintong,Yanliang districts and Gaoling County water quality poor zone.