环境工程学报2026，Vol.20Issue(4)：1042-1059,18.DOI:10.12030/j.cjee.202507013
西南岩溶地下河水化学特征及健康风险评价—以广西平江地下河为例
Hydrochemical characteristics and health risk assessment of karst underground rivers in southwest China:A case study of the Pingjiang underground river in Guangxi
摘要
Abstract
The groundwater system in the karst regions of Southwest China is crucial for ensuring water supply security in traditional agricultural areas and maintaining ecosystem health.Assessing the water quality and ecological risks of karst groundwater is therefore of strategic importance for regional ecological conservation and sustainable development.This study focused on the representative Pingjiang Underground River Basin.42 groundwater samples across high-flow,normal-flow,and low-flow periods were collected.A comprehensive hydrochemical analysis was conducted to identify the primary factors influencing groundwater chemistry,and the Objective Comprehensive Weight Water Quality Index(OCWQI)alongside human health risk assessment models were employed to evaluate groundwater quality and associated health risks.The results indicated that the dominant anions and cations in the groundwater were HCO3-and Ca2+,respectively.The groundwater was generally weakly alkaline and slightly hard,with chemical constituent concentrations following the sequence:low-flow period>normal-flow period>high-flow period.The hydrochemical type across the basin was consistent,classified entirely as HCO3-Ca.Groundwater hydrochemistry in the Pingjiang Underground River Basin was primarily governed by rock weathering processes,particularly of carbonate and silicate rock,while also being notably influenced by anthropogenic activities.This influence was evidenced by elevated nitrate(NO3-)concentrations attributable to agricultural practices.Health risk assessment revealed that during the normal-flow and low-flow periods,64％and 79％of groundwater samples,respectively,exceeded the natural threshold for NO3-(3 mg·L-1)for adults,corresponding to a low-risk level(Hazard Index,0.09<RHI<0.30).For children,the proportions were 64％and 86％during the same periods,exceeding the same threshold and reaching a lower threshold for risk(0.06<RHI<0.20),indicating potential low-level non-carcinogenic health risks,particularly for younger populations.The spatial patterns of groundwater quality degradation aligned closely with the distribution of NO3--related health risks,showing a stepwise increase from northwest to southeast and consistently higher risk levels for children compared to adults.These findings provide valuable insights for the sustainable use and protection management of groundwater resources in the Pingjiang Underground River Basin and analogous karst regions.关键词
地下水质量/水化学/NO3-/平江地下河流域/健康风险评价Key words
groundwater quality/hydrochemistry/nitrate/Pingjiang underground river basin/health risk assessment分类
资源环境引用本文复制引用
覃佳肖,郑焕君,李金明,冯俊海,侯萍萍,张勤军,黄春阳,贝为昶..西南岩溶地下河水化学特征及健康风险评价—以广西平江地下河为例[J].环境工程学报,2026,20(4):1042-1059,18.基金项目
广西科技重大专项(桂科 AA24206020) （桂科 AA24206020）
广西重点研发计划(桂科 AB25069497) （桂科 AB25069497）
国家自然科学基金资助项目(42372294) （42372294）
广西地质矿产勘查开发局"广西靖西市坡豆河流域岩溶碳汇调查评价"(GXDK202405) （GXDK202405）
