摘要
为了加深对黑河上游水循环过程的理解,以研究区5个站点2015年8月至2016年8月的降水同位素实测数据和气象数据为基础,除对降水同位素特征进行分析外,主要利用TrajStat软件中的后向轨迹计算模块与潜在源贡献因子分析(PSCF)方法,对研究区降水的水汽来源进行了分析,并结合水汽通量等方法进行了补充分析。结果表明:降水同位素呈夏高冬低趋势,大气水线斜率(8.02)和截距(11.02)均高于全球大气水线的斜率(8.00)和截距(10.00),存在温度效应(δ18O=0.43x-10.82,r=0.54,P<0.0001),不存在降水量效应(δ18O=-0.05x-7.81,r=0.03,P<0.0001);研究区降水受多种水汽影响,西风水汽影响最大。夏季除受西风水汽影响外,还受东南季风水汽影响显著且水汽来源复杂;研究区夏季的潜在蒸发源地集中在一些相对湿度和蒸发量较大的地区,如祁连山区、河西地区、柴达木盆地北部、青藏高原东南部及酒泉地区西南部等;当降水量小、温度高时,持续性降水的大气水线方程的斜率和截距较小,暴雨稳定同位素值较贫化,受东南季风水汽影响最大,其次是北方和西风水汽,多种水汽辐合是暴雨事件发生的必要条件。
In order to deepen the understanding of the process of water circulation in the upper reaches of Heihe River,based on the measured data of precipitation isotopes and meteorological data from 5 sites in the study area from Augus t2015 to August 2016,in addition to the analysis of precipitation isotope characteristics,TrajStat software is mainly used.The backward trajectory calculation module and the potential source contribution function analysis(PSCF)method focus on the analysis of the water vapor source of the precipitation in the study area,and supplement the analysis with the method of water vapor flux.The results show that:(1)The precipitation isotope is obviously low in summer and high in winter,and the slope(8.02)and intercept(11.02)of the meteoric water line in the study area are higher than the slope(8)and intercept(10)of the global atmospheric waterline.There is a temperature effect(δ18 O=0.43 x-10.82,r=0.54,P<0.0001),there is no precipitation effect(δ18 O=-0.05 x-7.81,r=0.03,P<0.0001);(2)Precipitation in the study area is affected by many kinds of water vapor,and the west wind water vapor has the greatest influence.In summer,except the west wind water vapor,the southeast water vapor has obvious influence and the source of water vapor is complicated;(3)The potential evaporation sources in the study area are mainly concentrated in some areas with large evaporation and relatively high humidity,such as:Qilian Mountains,Hexi area,northern part of the Qaidam Basin,the southeastern part of the plateau and the southwestern part of the Jiuquan area are the main potential evaporation sources for summer precipitation in the study area;(4)When precipitation is small and temperature is high,the slope and intercept of atmospheric water line equation of continuous precipitation are small.The stable isotope value of rainstorm is relatively depleted,which is most affected by water vapor of southeast monsoon,followed by water vapor of north and west wind,a variety of water vapor convergence is a necessary condition for the occurrence of heavy rain events.
作者
孟鸿飞
张明军
王圣杰
邱雪
周苏娥
张亚宁
余秀秀
王雯
MENG Hongfei;ZHANG Mingjun;WANG Shengjie;QIU Xue;ZHOU Su’e;ZHANG Yaning;YU Xiuxiu;WANG Wen(College of Geography and Environmental Science,Northwest Normal University,Lanzhou 730070,China;Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;Key Laboratory for Ecology and Environment of River Wetlands in Shaanxi Province,Weinan 714099,Shaanxi;MOE Engineering Center of Desertification and Blown-sand Control,Beijing Normal University,Beijing 100875,China)
出处
《冰川冻土》
CSCD
北大核心
2020年第3期937-951,共15页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(41461003,41771035)
甘肃省高等学校科研项目(2018C-02)资助。
关键词
黑河上游
降水同位素
水汽来源
潜在蒸发源地
典型降水事件
the upper reaches of Heihe River
precipitation isotope
water vapor source
potential evaporation source
typical precipitation event
