Wang Xuemei, Li Bo, Zhu Mingtan, Tang Jie, Liu Guo, Wang JinJin, Wang Yanqun, Hu Jinzhao
College of Environment Civil Engineering, Chengdu University of Technology, Chengdu 610059, PR China; School of Environment and Resource, Xichang University, Xichang 615000, PR China; State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu 610059, PR China; State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation & Water Pollution, College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China.
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu 610059, PR China; State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation & Water Pollution, College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China; College of Environmental Science and Engineering, China West Normal University, Nanchong 10637001, PR China.
Sci Total Environ. 2024 Dec 20;957:177747. doi: 10.1016/j.scitotenv.2024.177747. Epub 2024 Nov 27.
Mining activities have led to significant rare earth elements (REEs) contamination and ecotoxicological risks in aquatic systems. However, the concentration, speciation, and primary controlling factors of REEs in aquatic systems in southwest China have remained unclear. This study investigated the water geochemistry, concentration, speciation, fractionation patterns, and anomalies of REEs in the surface water, shallow groundwater, and deep groundwater within a mining-impacted catchment area in southwest China across different seasons. REE concentrations were in the range of 1.12-73.66 μg/L in surface water, 0.09-96.58 μg/L in shallow groundwater, and 0.09-1.05 μg/L in deep groundwater. Seasonal variations significantly impacted REE concentrations in surface water and shallow groundwater. The variability of environmental parameters, driven by higher temperatures during the wet season, significantly controlled the increases in the proportions of dissolved REE in both surface water and groundwater. The water recharge between surface water and groundwater resulted in analogous REE fractionation patterns and anomalies. Variation in pH, oxidation-reduction potential, iron, manganese and aluminum content in water influenced the fractionation indices of REEs. Cerium and europium anomalies in water samples provided insights into REE sources and associated hydrological dynamics. Our results demonstrate that REE fractionation patterns and anomalies were influenced by water-rock interactions, mining activities and hydrogeological factors, which facilitates a comprehensive understanding of the hydrogeochemistry process in aqueous systems.
采矿活动已导致水生系统中出现显著的稀土元素（REEs）污染和生态毒理风险。然而，中国西南地区水生系统中稀土元素的浓度、形态及主要控制因素仍不明确。本研究调查了中国西南某受采矿影响集水区内不同季节地表水、浅层地下水和深层地下水中稀土元素的水地球化学、浓度、形态、分馏模式及异常情况。地表水中稀土元素浓度范围为1.12 - 73.66μg/L，浅层地下水中为0.09 - 96.58μg/L，深层地下水中为0.09 - 1.05μg/L。季节变化对地表水和浅层地下水中稀土元素浓度有显著影响。雨季较高温度驱动的环境参数变化显著控制了地表水和地下水中溶解态稀土元素比例的增加。地表水与地下水之间的水体补给导致了类似的稀土元素分馏模式和异常情况。水体中pH值、氧化还原电位、铁、锰和铝含量的变化影响了稀土元素的分馏指数。水样中的铈和铕异常为稀土元素来源及相关水文动力学提供了见解。我们的结果表明，稀土元素分馏模式和异常受水 - 岩相互作用、采矿活动和水文地质因素影响，这有助于全面理解水系统中的水文地球化学过程。
