巴丹吉林沙漠东南部湖泊和地下水的氢氧同位素特征  

Features of Hydrogen and Oxygen Isotopes in Lakes and Groundwater in Southeast Badain Jaran Desert

作　　者：张华安[1] 王乃昂[1] 李卓仑[1] 董春雨[1] 陆莹[1] 李贵鹏[1] 

机构地区：[1]兰州大学资源环境学院/干旱区水循环与水资源研究中心,甘肃兰州730000

出　　处：《中国沙漠》2011年第6期1623-1629,共7页Journal of Desert Research

基　　金：国家基础科学人才培养基金项目(J1030519);高等学校博士学科点专项科研基金项目(20090211110025);国家自然科学基金项目(50879033)联合资助

摘　　要：通过对巴丹吉林沙漠湖泊和地下水氢氧同位素分析,讨论了沙漠湖水和地下水的补给关系,并结合地下水可溶性固体总量的特征,进一步探讨了巴丹吉林沙漠的蒸发特性。根据氢氧同位素的分析结果,本研究区的蒸发趋势线方程为:δD=4.1δ18O-30.02‰(n=37,R2=0.94)较低的斜率显示了巴丹吉林沙漠强烈的蒸发环境特征。巴丹吉林沙漠东南部湖泊和地下水具有相似的蒸发趋势,推测两者之间存在补给关系。根据沙漠腹地地下水氧同位素值富集程度高于东南部地下水氧同位素值的特点,得出前者蒸发较后者强烈。进而对比其他干旱条件下盐湖的蒸发,结果显示巴丹吉林沙漠湖水存在过度蒸发效应。The Badain Jaran Desert is located in the centre of the Alxa Plateau to north of the Qilian Mountains and the Tibetan Plateau.It is the second largest desert in China with an area of 52 162 km2.Elevation in the interior of the Badain Jaran ranges from 1 500 m in the southeast to 900 m in the northwest,producing a regional hydraulic gradient from SE to NW.The unique desert environment with its lakes attracted many scientific investigations,so in this paper,by analyzing hydrogen and oxygen isotopes in the desert lakes and groundwater in the southeast of Badain Jaran Desert,connecting with totally dissolved solids（TDS） of groundwater,we discussed the recharge relationship between lakes and groundwater in the desert area,and made a further investigation on the evaporation in the Badain Jaran Desert.The hydrogen and oxygen isotope test indicated that the averaged δD and δ18O compositions had a relationship of δD=4.1δ18O-30.02‰（n=37,R2=0.94）,and the low slope of the evaporation line indicated the enhanced evaporation in the Badain Jaran Desert.The lakes had a similar evaporation trend with the groundwater in the southeast Badain Jaran Desert,and it implied that there was some degree of recharge between them.Comparison of the isotopic enrichment degrees of groundwater in the central region and the southeastern parts of the desert showed that the groundwater evaporated in the central region was more severe than in the southeast margin.Comparison of the evaporation of lagoon in the study area and in other arid regions illustrated that the lakes in the Badain Jaran Desert were affected by the effect of excessive evaporation.

关 键 词：巴丹吉林沙漠 氢氧同位素 地下水 大气降水线 蒸发效应 

分 类 号：P342[天文地球—水文科学]