南水入冀新水情下，百泉泉域地下水环境发生改变，岩溶地下水地球化学过程有待查明。综合利用数值模拟、机器学习(自组织聚类)和同位素(δD和δ¹⁸O)等方法系统揭示了矿业活动与南水入冀下百泉泉域岩溶地下水地球化学过程，并基于熵变权水质指数( Entropy-weighted water quality index， EWQI)进行了水质分级评价。南水入冀后，百泉泉域岩溶地下水位整体抬升。时间上，呈现出既有年际动态变化又有年内季节变化特征。空间上，补给区表现为剧变型，而径流、排泄区呈缓变型。地下水降落漏斗主要分布在泉域东南部的煤、铁矿密集区。泉域岩溶地下水呈弱碱性，水化学类型以Ca−HCO₃型和Ca−SO₄型为主导。主要阴阳离子质量浓度遵循ρ(${mathrm{HCO}}_3^{-} $) > ρ(${mathrm{SO}}_4^{2-} $) > ρ(Cl⁻)和ρ(Ca²⁺) > ρ(Mg²⁺) > ρ(Na⁺) > ρ(K⁺)的顺序。各离子沿着径流路径呈现出逐渐增大的空间分布特征。岩溶地下水化学成分主要受岩石(方解石、白云石和石膏)风化溶解和反向阳离子交换作用主导。人为活动对泉域岩溶地下水系统中的${mathrm{SO}}_4^{2-} $和${mathrm{NO}}_3^{-} $质量浓度有一定程度影响。岩溶地下水来源于大气降水，并且在入渗前发生了二次蒸发作用，氘盈余值在径流过程中有所降低。水质评价结果表明，岩溶地下水质量整体优于第四系地下水，分别有50%的岩溶水和37.5%的第四系水样满足饮用目的。TDS、ρ(${mathrm{SO}}_4^{2-} $)和ρ(${mathrm{NO}}_3^{-} $)是影响泉域地下水水质的关键指标。引起泉域岩溶地下水系统水质恶化的潜在人类活动主要包括矿山排水、农业灌溉和城市污水排放。通过水质分级评价，提出了泉域地下水环境保护措施。研究结果将有助于为百泉泉域岩溶地下水资源的供水安全和地下水环境保护治理提供参考。

Under the new water situation of the south water into Hebei, the groundwater environment of Baiquan Spring area has been changed, and the geochemical process of karst groundwater needs to be clarified.In this research, numerical simulation, machine learning (self-organized clustering) and isotope (δD and δ¹⁸O) methods were used to systematically reveal the geochemical processes of karst groundwater in the Baiquan Spring area under the mining activities and the inflow of water from the south into Hebei Province, and the water quality was evaluated on the basis of entropy-variable weighted water quality index(EWQI). After the entry of south water into Hebei, the karst groundwater level in the Baiquan spring area was raised as a whole. Temporally, it presented both inter-annual dynamic changes and intra-annual seasonal changes. Spatially, the recharge area displayed a drastic change type, while the runoff and discharge areas showed a slow change type.The groundwater dropping funnel was mainly distributed in the coal and iron ore intensive area in the southeast of the spring area. The karst groundwater in the spring area was weakly alkaline, and the hydrochemical types were dominated by Ca−HCO₃ and Ca−SO₄ types. The major anion and cation concentrations followed the order of ρ(${mathrm{HCO}}_3^{-} $) > ρ(${mathrm{SO}}_4^{2-} $) > ρ(Cl⁻) and ρ(Ca²⁺) > ρ(Mg²⁺) > ρ(Na⁺) > ρ(K⁺). The ions showed a gradually increasing distribution pattern along the runoff path.Karst groundwater chemistry was dominated by weathering dissolution of rocks (calcite, dolomite and gypsum) and reverse cation exchange.The contents of ${mathrm{SO}}_4^{2-} $ and ${mathrm{NO}}_3^{-} $ in karst groundwater system in spring were affected by anthropogenic activities to some extent.Karst groundwater was derived from atmospheric precipitation and underwent secondary evaporation prior to infiltration, with the deuterium surplus value being reduced during runoff.The results of the water quality evaluation showed that the quality of karst groundwater was overall better than quaternary groundwater. Approximately 50% of the karst water and 37.5% of the quaternary water samples were suitable for drinking purposes, respectively. TDS, ρ(${mathrm{SO}}_4^{2-} $) and ρ(${mathrm{NO}}_3^{-} $) are crucial indicators affecting groundwater quality in the spring area.Potential anthropogenic activities causing water quality degradation in the karst groundwater system of the springs mainly include mine drainage, agricultural irrigation, and urban sewage discharge.Groundwater environmental protection measures for the spring area were proposed through water quality grading evaluation.The research results will be helpful to provide reference for the safety of water supply and the protection of groundwater environment in Baiquanspring area.