拉林河流域地下水中稀土元素质量浓度及分异特征  

Mass concentrations and patterns of rare earth elements in groundwater of Lalin River basin

作　　者：王慧群 胡斌 滕彦国[1,2] 詹燕红 翟远征[1,2] WANG Huiqun;HU Bin;TENG Yanguo;ZHAN Yanhong;ZHAI Yuanzheng(College of Water Sciences,Beijing Normal University,Beijing 100875,China;Engineering Research Center of Groundwater Pollution Control and Remediation,Ministry of Education,Beijing 100875,China;Key Laboratory of Drinking Water Science and Technology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]北京师范大学水科学研究院,北京100875 [2]地下水污染控制与修复教育部工程研究中心,北京100875 [3]中国科学院生态环境研究中心饮用水科学与技术重点实验室,北京100085 [4]中国科学院大学,北京100049

出　　处：《南水北调与水利科技（中英文）》2021年第1期158-167,共10页South-to-North Water Transfers and Water Science & Technology

基　　金：国家自然科学基金(41877355);北京高精尖学科“陆地表层学”资助。

摘　　要：为了解拉林河流域地下水中稀土元素(REE)的地球化学特征,通过稀土元素质量浓度测试和北美页岩(NASC)归一化分析研究区域地下水系统中稀土元素的质量浓度和分异特征,利用软件PHREEQC模拟计算研究稀土元素沿流向的形态分布特征。结果表明:拉林河流域地下水中稀土元素总质量浓度(ΣREE)较低,范围为0.030~2.649μg/L(均值0.328μg/L);轻稀土元素(LREE)相对亏损,而重稀土元素(HREE)相对富集,具有显著Eu正异常和轻度Ce负异常;地下水中稀土元素主要以LnCO_(3)+和Ln(CO_(3))2-形态存在;随径流距离增加,地下水中ΣREE质量浓度明显下降,Eu正异常程度增大,LnCO_(3)+和Ln(CO_(3))2-形态质量浓度分别呈下降和上升趋势,稀土元素形成二碳酸配合物是造成重稀土元素相对富集的主要原因。To understand the geochemical characteristics of rare earth elements(REE)in groundwater of Lalin River basin,the rare earth elements in the regional groundwater system were studied through rare earth element mass concentration testing and North American Shale Composite(NASC)normalized analysis.The distribution characteristics of REE speciation along the groundwater flow path were studied using PHREEQC software modeling.The results showed that:the total amount of rare earth elements(ΣREE)in the groundwater of the Lalin River basin ranged from 0.030 to 2.649μg/L(mean value 0.328μg/L);Light Rare Earth Elements(LREE)is quite depleted,while Heavy Rare Earth Elements(HREE)are relatively enriched,with significant positive Eu anomalies and mild Ce negative anomalies;the REE in the groundwater mainly existed in the form of LnCO_(3)+and Ln(CO_(3))_(2)^(-);along the regional groundwater flow path,the groundwater in Lalin River basin demonstrated the decline ofΣREE concentration and the increase of positive Eu anomalies.Furthermore,LnCO_(3)^(+)concentrations decreased and Ln(CO_(3))_(2)^(-)increased respectively along the groundwater flow path;the formation of dicarbonate complexes of rare earth elements was the main reason for the relative enrichment of HREE.

关 键 词：拉林河 地下水 稀土元素 配分模式 Eu/Ce异常 稀土元素形态 

分 类 号：X142[环境科学与工程—环境科学]