Spatial variation of stable isotopes in different waters during melt season in the Laohugou Glacial Catchment, Shule River basin  

作　　者：WU Jin-kui DING Yong-jian YANG Jun-hua LIU Shi-wei CHEN Ji-zu ZHOU Jia-xin QIN Xiang 

机构地区：[1]Laboratory of Watershed Hydrology and Ecology, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences [2]Qilian Shan station of Glaciology and Ecologic Environment, State Key Laboratory of Cryospheric Science, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences [3]Institute for Landscape Ecology and Resources Management, Justus-Liebig-University Giessen

出　　处：《Journal of Mountain Science》2016年第8期1453-1463,共11页山地科学学报（英文）

基　　金：the projects of National Major Scientific Research Project (2013CBA01806);National Natural Science Foundation of China (Grant Nos. 41271085,41130641);open fund project of State Key Laboratory of Cryospheric Science (SKLCS-OP2013-05)

摘　　要：To evaluate isotopic tracers at natural abundances by providing basic isotope data of the hydrological investigations and assessing the impacts of different factors on the water cycle, a total of 197 water samples were collected from the Laohugou Glacial catchment in the Shule River basin northwestern China during the 2013 ablation seasons and analyzed their H- and O-isotope composition. The results showed that the isotopic composition of precipitation in the Qilianshan Station in the Laohugou Glacial catchment was remarkable variability. Correspondingly, a higher slope of δ180-δD diagram, with an average of 8.74, is obtained based on the precipitation samples collected on the Glacier No.la, mainly attributed to the lower temperature on the glacier surface. Because of percolation and elution, the bottom of the firn the isotopic composition at is nearly steady. The 6180 /altitude gradients for precipitation and melt water were -o.37%o/100 m and -o.34%o/100 m, respectively Exposed to the air and influenced by strong ablation and evaporation, the isotopic values and the 6180 vs 6D diagram of the glacial surface ice show no altitudinal effect, indicating that glacier ice has the similar origins with the firn. The variation of isotopic composition in the melt water, varying from -l0.7‰ to -16.9‰ （8180） and from -61.1%o to -122.1%o （6D） indicates the recharging of snowmelt and glacial ice melt water produced at different altitudes. With a mean value of -13.3‰ for 8180 and -89.7‰ for 8D, the isotopic composition of the stream water is much closer to the melt water, indicating that stream water is mainly recharged by the ablation water. Our results of the stable isotopic compositions in natural water in the Laohugou Glacial catchment indicate the fractionations and the smoothing fluctuations of the stable isotopes during evaporation, infiltration and mixture.

关 键 词：Stable isotopes Precipitation/snow/ice Altitude effect Melt water Laohugou GlacialCatchment Qilian Mountains 

分 类 号：P342[天文地球—水文科学]