基于因子分析的岩溶地下水水质影响因素研究——以毕节市大方县南部为例

Study on Influencing Factors of Karst Groundwater Quality Based on Factor Analysis——Take the Southern Part of Dafang County,Bijie City as an Example

为了解研究区岩溶地下水水质形成及离子质量浓度空间变异影响因素,以毕节市大方县南部为研究区,采用因子分析方法对56组水样进行分析,得到基于研究区岩溶地下水水质形成及其影响的4组因子(F1、F2、F3、F4):F1以TH、TDS、COD、Ca^(2+)、SO_(4)^(2-)、F^(-)为主,代表了碳酸盐岩及膏盐矿物的充分溶解对水质的影响;F2以游离CO_(2)、Mg^(2+)、HCO_(3)^(-)为主,反映了碳酸盐岩中白云石矿物的溶解对水质的影响;F3以Na^(+)、K^(+)、Cl^(-)为主,代表了盐岩溶解、大气降水对水质的影响;F4以pH、NO_(3)^(-)为主,揭示了人类生活污水和农业灌溉污水对岩溶地下水水质的影响。以上4种因子可以解释研究区岩溶地下水水质影响因素的80%以上。

In order to understand the influencing factors of karst groundwater quality formation and spatial variation of ion mass concentration in the study area,the southern part of Dafang County in Bijie city is taken as the research area,56 groups of water samples were analyzed by factor analysis method,and four groups of factors(F1,F2,F3 and F4)were obtained based on karst groundwater quality formation and its influence in the study area:F1 is dominated by TH,TDS,COD,Ca^(2+),SO_(4)^(2-)and F^(-),representing the influence of co-dissolution of carbonate rock and gypsolyte on water quality.F2 is dominated by free CO_(2),Mg^(2+)and HCO_(3)^(-),reflecting the influence of dolomite dissolution on water quality in carbonate rocks.F3 is dominated by Na^(+),K^(+) and Cl^(-),representing the influence of salt rock dissolution and atmospheric precipitation on water quality.F4 is dominated by pH and NO_(3)^(-),revealing the impact of human domestic sewage and agricultural irrigation sewage on karst groundwater quality.The above four factors can explain more than 80%of the influencing factors of karst groundwater quality in the study area.