To gain an in-depth understanding of the groundwater environmental quality and its dynamic changes in the Daqing River Basin, the detection and distribution of 20 heavy metals and 40 organic micropollutants in the groundwater of the basin were investigated. The results indicate that the overall groundwater quality in Daqing River Basin is relatively good, with 77.19% of the monitoring sites meeting the Class III groundwater quality standard. However, heavy metals and emerging organic compounds still pose potential threats to regional water security. There were 10 heavy metals exceeding the standard, with manganese and iron showing the highest exceedance rates, with concentration ranges of ND–1421.00 and ND–42300.00 μg/L, respectively. The major excessive emerging organic substances were 1,2-dichloroethane and atrazine, with concentration ranges of ND–90.00 and ND–2.86 μg/L, respectively. The concentration ranges of total volatile organic compounds, total polycyclic aromatic hydrocarbons, and total pesticides were ND–90.00, ND–0.01 and ND–3.91 μg/L. Significant differences were observed in the concentrations of certain heavy metals (such as silver and cadmium) in groundwater between piedmont and plain regions, as well as notable variations in pesticide and polycyclic aromatic hydrocarbon concentrations across different aquifer types (unconfined and confined groundwater). Natural environmental conditions, including soil properties and mineral distribution, are the primary factors influencing the presence of heavy metals in groundwater, while agricultural activities and domestic wastewater discharge are the main sources of organic micropollutants. Overall, the groundwater in plain regions exhibits a higher suitability for drinking purposes compared with mountainous areas. The findings of this study reveal the evolutionary characteristics of groundwater environments in typical urban agglomerations in China and emphasize the importance of protecting groundwater quality in key water source areas. 

Beijing-Tianjin-Hebei region, Daqing River Basin, water resource distric, groundwater quality, drinking water applicability, heavy metal, organic micropollutants

为深入理解大清河流域地下水环境质量及其动态变化, 调查大清河流域地下水中20种重金属和40种有机微污染物的检出及分布情况。结果显示, 大清河流域地下水的水质整体上较好, 77.19%的监测站点符合地下水Ⅲ类水质标准。然而, 重金属和新型有机物对区域水安全仍然构成潜在威胁。超标重金属组分有10项, 超标率最高的两种重金属为锰和铁, 浓度范围分别为ND~1421.00和ND~42300.00 μg/L; 超标的新型有机物主要为1,2-二氯乙烷和莠去津, 浓度范围分别为ND~90.00和ND~2.86 μg/L; 总挥发性有机物、总多环芳烃和总农药浓度范围分别为ND~90.00, ND~0.01和ND~3.91 μg/L。山前和平原地区地下水中的个别种类重金属(银和镉等)浓度存在显著差异, 不同含水层类型(潜水和承压水)的农药和多环芳烃类物质浓度存在较明显的差异。土壤属性和矿物分布等自然环境条件是地下水中重金属赋存的主要影响因素, 农业生产活动和生活废水排放是有机微污染物的主要来源。总的来说, 平原区地下水的饮用水适用性水平高于山区。研究结果揭示了中国典型城市群地下水环境的演化特征, 强调了关键水源区地下水质量保护的意义。