典型高寒流域冲洪积扇地下水与地表水交互机制  

Groundwater⁃Surface Water Interaction and Its Mechanism in a Piedmont Fluvial⁃Alluvial Fan of an Alpine Watershed

作　　者：杨泽森 常启昕 贺笙哲 廖习锐 Yang Zesen;Chang Qixin;He Shengzhe;Liao Xirui(College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China;State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China;School of Environmental Studies,China University of Geosciences,Wuhan 430074,China)

机构地区：[1]成都理工大学环境与土木工程学院,四川成都610059 [2]地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [3]中国地质大学环境学院,湖北武汉430074

出　　处：《地球科学》2025年第2期687-698,共12页Earth Science

基　　金：国家自然科学基金项目(Nos.42102301,41772270,91325101).

摘　　要：差分流量测量、一维热传输方程、环境同位素和水化学等常规手段仍不能精细刻画高寒流域冲洪积扇复杂河段地下水与地表水交互机制.因此,利用分布式光纤对葫芦沟流域冲洪积扇东支到干流河段的河床与河水表面进行高时空分辨率的连续温度监测,发现东支观测河段有12个地下水排泄点,干流观测河段均为地下水排泄带,排泄方式分别为集中流和扩散流.并结合该流域的水文地质条件,提出了高寒流域冲洪积扇地下水与地表水交互作用概念模型,描绘了局部河段地下水排泄点/带,认为粉质粘土体的存在影响了地下水与河水的交互关系.高寒流域冲洪积扇含水层的非均质性是影响地下水与地表水交互关系的重要因素,且影响的时空范围会随着气候变暖而逐步增大.Conventional methods such as differential flow gauging,one-dimensional heat transport equations,and environmental isotopic and geochemical tracers are often used to study the interaction mechanism between groundwater and surface water in alpine watersheds.However,they can not accurately describe this mechanism on a small scale,such as the complex stream stretches of a piedmont fluvial-alluvial fan.Therefore,the piedmont fluvial-alluvial fan in the Hulugou Valley in the headwaters of the Heihe River was chosen as our study site.Discrete zones of groundwater discharge along the stream stretches from the east tributary to the mainstream were identified on the basis of variations in streambed temperature using a distributed temperature sensor(DTS).The DTS gives measurements of the spatial(±1 m)and temporal(10 min)variation of streambed temperature over a much larger reach of stream(~883 m)than previous methods.Results show that focused groundwater discharge has been identified in twelve points along the east tributary,and groundwater discharge in the mainstream has been dominated by diffuse flow.Combining the hydrogeology of this catchment,we build the conceptual model of interactions between groundwater and surface water in a piedmont fluvial-alluvial fan.The heterogeneity of fluvial-alluvial aquifers in the alpine watershed controls and impacts groundwater flow and its interaction with surface water.Furthermore,the impact′s space-time scope will gradually increase with climate warming.

关 键 词：高寒流域 冲洪积扇 分布式光纤测温 非均质性 地下水与地表水交互 

分 类 号：P641[天文地球—地质矿产勘探]