青藏高原不同水体氢氧稳定同位素特征  

Stable isotopic characteristics of hydrogen and oxygen in different water bodies in the Qinghai-Tibet Plateau

作　　者：徐忠宝 杨丽萍 翁白莎[3] 严登华[3] 彭辉[1] XU Zhongbao;YANG Liping;WENG Baisha;YAN Denghua;PENG Hui(College of Hydraulic&Environment,China Three Gorges University,Yichang 443002,China;Beifang Investigation,Design&Research Co.,Ltd,Tianjin 300222,China;State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100038,China)

机构地区：[1]三峡大学水利与环境学院,湖北宜昌443002 [2]中水北方勘测设计研究有限责任公司,天津300222 [3]流域水循环模拟与调控国家重点实验室中国水利水电科学研究院,北京100038

出　　处：《南水北调与水利科技（中英文）》2024年第3期521-533,共13页South-to-North Water Transfers and Water Science & Technology

基　　金：第二次青藏高原综合科学考察研究项目(2019QZKK0207-02);国家优秀青年科学基金项目(52022110)

摘　　要：为揭示青藏高原区域水文循环机制和促进水资源合理利用,基于氢氧稳定同位素技术分析不同水体氢氧稳定同位素特征和转化关系,应用端元混合径流分割模型和IsoSource软件进行流域水源解析。结果表明:区域大气降水δ(^(18)O)值2—5月上升、5—10月下降;氘盈余值冬季高夏季低;δ(^(18)O)在青藏高原北部地区表现出“逆海拔效应”,区域内其他地区“海拔效应”明显。河水、湖水、地下水的平均蒸发损失量分别为20.8%、30.9%、23.6%。河水氢氧稳定同位素的沿程变化受补给水源和蒸发作用影响,降水补给使得河水δ(^(18)O)减小,重同位素相对富集的地下水补给导致河水δ(^(18)O)增大,蒸发作用使得河水δ(^(18)O)增大,蒸发效应使得湖水重同位素富集,湖水注入河道后导致河水δ(^(18)O)增大。降水是拉萨河流域的最主要补给水源,而对于疏勒河流域的补给水源来说,降水和地下水平均贡献率相近,岷江流域则以地下水补给居多。那曲河流域下游受错那湖调节,随着沿程距离的增加,湖水补给贡献率呈下降趋势。Over the years,great progress was made in the study ofδ(D)andδ(^(18)O)in the Qinghai-Tibet Plateau.However,a comprehensive systematic study of the entire Qinghai-Tibet Plateau was lacking,and much of the research focused on the spatial and temporal patterns and evolutionary mechanisms of precipitation stable isotopes.There was a lack of systematic research at the basin scale for runoff source analysis,and further exploration was needed on the relationships between different runoff components.The available data was used to analyze theδ(D)andδ(^(18)O)values of different types of water samples on the Qinghai-Tibet Plateau to investigate their characteristics.Hydrogen and oxygen stable isotopic data were obtained mainly from the following aspects:(1)Water samples were collected in the Naqu River basin from August 2016 to June 2023,and the stable isotope values of hydrogen and oxygen were measured;(2)Global Network of Isotope in Precipitation(GNIP;https://www.iaea.org/services/networks/gnip);(3)National Qinghai-Tibet Plateau/Third Pole Environment Data Center(TPDC;https://data.tpdc.ac.cn);(4)Stable isotope values of hydrogen and oxygen in the Qinghai-Tibet Plateau studied by predecessors.Water samples collected in the Naqu River basin were analyzed and tested using the L2130-i Water Isotope Analyzer(Picarro,USA),which indicated the stable isotope ratio with respect to the Vienna Standard Mean Ocean Water(V-SMOW).The Local Meteoric Water Line(LMWL)wasδ(D)=8.25δ(^(18)O)+16.85.Theδ(^(18)O)value increased from February to May and decreased from May to October.A high deuterium surplus value was observed in winter,while it was low in summer.An"inverse altitude effect"was demonstrated by the stable isotopes in the northern part of the Qinghai-Tibet Plateau,while other areas exhibited an obvious"altitude effect".When comparing with the local atmospheric precipitation line and the global atmospheric precipitation line,it was found that both the slope and intercept of the river water line of the Minjiang River and the Da

关 键 词：青藏高原 稳定同位素 降水 河水 湖水 地下水 

分 类 号：X143[环境科学与工程—环境科学]