Abstract:
10 indicators of 26 groups of karst groundwater samples in the study area were comprehensively analyzed to study the groundwater chemical characteristics of the Pingyin-Dong'e hydrogeological unit by correlation analysis, factor analysis and cluster analysis. The results showed that the groundwater hydrochemical types in the study area were dominated by HCO3-Ca·Mg and HCO3-Ca. The chemical composition of groundwater in the recharge, runoff and discharge areas showed significant differences. The main factors controlling the composition of karst groundwater were NO-3, SO42-, Na+ and Ca2+, which can reflect 71.20% of the information volume of the sample. NO-3 and SO42- were mainly affected by industrial production and human activities, with a contribution rate of 31.98%. Na+ was mainly affected by human activities, with a contribution rate of 22.65%. Ca2+ was mainly affected by the weathering-solubility of limestone, and with a contribution rate of 20.17%.