The elevation gradient of stable isotopes in precipitation in the eastern margin of Tibetan Plateau  

作　　者：Jie LI Zhonghe PANG 

机构地区：[1]Engineering Research Center of Groundwater Pollution Control and Remediation of Ministry of Education,College of Water Sciences,Beijing Normal University,Beijing 100875,China [2]Key Laboratory of Shale Gas and Geoengineering,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China [3]Innovation Academy of Earth Science,Chinese Academy of Sciences,Beijing 100029,China [4]University of Chinese Academy of Sciences,Beijing 100049,China [5]Frontiers Science Center for Critical Earth Material Cycling,Nanjing University,Nanjing 210008,China

出　　处：《Science China Earth Sciences》2022年第10期1972-1984,共13页中国科学（地球科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 42130809 and 41602276);the Beijing Advanced Innovation Program for Land Surface Science of China;the Frontiers Science Center for Critical Earth Material Cycling Fund (Grant No. JBGS2102);the CRP Project of IAEA (Grant No. F31006)。

摘　　要：Tibetan Plateau(TP)receives moistures from different directions,so variations of isotope elevation gradient on different sides may exist.In this study,we systematically monitored and modeled the elevation effect of stable isotopes in precipitation of the eastern margin of the Tibetan Plateau,where we collected 265 water samples for stable isotope(δ2H andδ^(18)O)analyses,of which 70 are eventful rainfall samples,and 195 are surface water samples,for comparison.Alpine lakes on the mountain peaks were used to reconstruct the average isotope composition of the local precipitation based on the evaporation effect.An elevation gradient of−4.2‰km^(−1)(R^(2)=0.93)was established for the eastern marginal region of TP.This elevation gradient was further confirmed by fractionation assessment using the Rayleigh fractionation model.This is the highest ever reported for the TP and it is the highest as compared to those of all the other slopes as well as that of the interior part of the TP.Precipitation isotopes in the interior of TP show a lower elevation gradient,which is likely caused by significant local moisture recycling.This paper also discusses the limitations of using river water samples to construct the elevation gradient.

关 键 词：Elevation gradient Stable isotopes Rayleigh fractionation Moisture recycling Tibetan Plateau 

分 类 号：P426.612[天文地球—大气科学及气象学]