鄱阳湖平原区多时间尺度大气降水稳定同位素变化及其与水汽来源的关系  

Variation of precipitation stable isotopes at multiple time scales and its associated with moisture sources in the Poyang Lake Plain

作　　者：雷蕊宇 丁梦瑶 吴华武[1] 范宏翔 李楷文 祝子淳 李静 付丛生 Lei Ruiyu;Ding Mengyao;Wu Huawu;Fan Hongxiang;Li Kaiwen;Zhu Zichun;Li Jing;Fu Congsheng(Nanjing Institute of Geography and Limnology,Key Laboratory of Watershed Geographic Sciences,Chinese Academy of Sciences,Nanjing 211135,Jiangsu,China;University of Chinese Academy of Sciences,Beijing 100049,China;College of Earth Sciences,Hunan Normal University,Changsha 410000,Hunan,China;School of Geographic Information and Tourism,Chuzhou University,Chuzhou 239000,Anhui,China)

机构地区：[1]中国科学院南京地理与湖泊研究所/中国科学院流域地理学重点实验室,江苏南京211135 [2]中国科学院大学,北京100049 [3]湖南师范大学地理科学学院,湖南长沙410000 [4]滁州学院地理信息与旅游学院,安徽滁州239000

出　　处：《地理科学》2025年第3期652-662,共11页Scientia Geographica Sinica

基　　金：国家自然科学基金项目(42071145,42201105)资助。

摘　　要：基于对鄱阳湖平原区降水的连续、长时间监测,利用氢氧稳定同位素(δD、δ^(18)O)示踪技术与后向轨迹模型,结合天气雷达图分析了该区庐山市牯岭镇和上饶市鄱阳县大气降水δD与δ^(18)O的组成特征及其变化反映的环境效应,探讨水汽来源和天气系统与其的联系。研究结果表明:年尺度上,2地大气降水线的斜率和截距均较全球大气降水线偏大,过量氘长期偏高,表明研究区气候湿润、大面积地表蒸发水汽参与降水,依据二源混合模型得出夏季湖泊蒸发水汽对鄱阳县降水的贡献比为15.4%,大于对牯岭镇的贡献(13.1%);水汽源区的变化导致季节尺度上降水δ^(18)O贫富变化明显,表现为春冬富集、夏秋贫化;连续降水主要受水汽类型与天气系统影响,冷锋降水δ^(18)O表现为逐渐下降,由冷锋转变为对流的降水δ^(18)O呈现“V”型变化。根据水汽源地(大陆与海洋)、路径距离(即轨迹所跨纬度)的差异,将连续降水的水汽划分为远源大陆水汽、近源大陆水汽、海洋性水汽3种类型,牯岭镇降水主要受到海洋性水汽的影响,鄱阳县降水主要受到近源大陆水汽的影响。Based on the continuous sampling and analysis of atmospheric precipitation in the Poyang Lake Plain area,utilized hydrogen and oxygen stable isotope tracing technology and the hybrid single particle lagrangian integrated trajectory model,combined with local meteorological monitoring data and weather radar analysis,to investigate the composition characteristics of atmospheric precipitation isotopes(δD,δ^(18)O)in Guling Town,Lushan City,and Poyang County,Shangrao City.The study also explored the environmental effects reflected by the isotopic variations and the influence of water vapor sources and weather systems.The results showed that,on an annual scale,the slopes and intercepts of the atmospheric precipitation lines in both locations are larger than the global atmospheric precipitation line.And the deuterium excess was consistently high,indicating a humid climate in the study area and the involvement of a large amount of surface evaporated water vapor in precipitation.According to the twocomponent mixing model,it was determined that the contribution of lake evaporated water vapor to precipitation in Poyang County(15.4%)was higher than in Guling Town(13.1%)during the summer.The variation in water vapor sources led to significant isotopic variations in precipitation on a seasonal scale,characterized by enrichment in spring and winter and depletion in summer and autumn.Continuous precipitation was mainly influenced by the types of water vapor and weather systems.The δ^(18)O of precipitation during cold frontal precipitation showed a gradual decrease,while the δ^(18)O of precipitation during the transition from cold fronts to convection exhibited a“V”-shaped variation.Based on the differences in water vapor sources(continental and oceanic)and trajectory distances(latitude span),the water vapor in continuous precipitation was classified into three types:distant continental water vapor,nearby continental water vapor,and marine water vapor.

关 键 词：鄱阳湖平原区 大气降水 稳定氢氧同位素 水汽来源 HYSPLIT模型 

分 类 号：P426.2[天文地球—大气科学及气象学]