Arid Zone Research ›› 2022, Vol. 39 ›› Issue (3): 820-828.doi: 10.13866/j.azr.2022.03.15

Previous Articles     Next Articles

Hydrogen-oxygen isotope characteristics of water bodies in the Xiangride-Qaidam River Basin and its influencing factors

HE Qixin1,2,3(),CAO Guangchao2,3,4(),CAO Shengkui1,2,3,CHENG Mengyuan1,2,3,DIAO Erlong1,2,3,GAO Siyuan1,2,3,QIU Xunxun1,2,3,ZHAO Meiliang1,2,3,CHENG Guo1,2,3   

  1. 1. School of Geographical Science of Qinghai Normal University, Xining 810008, Qinghai, China
    2. Qinghai Province Key Laboratory of Physical Geography and Environmental Process, Xining 810008, Qinghai, China
    3. MOE Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation, Xining 810008, Qinghai, China
    4. Academy of Plateau Science and Sustainability People’s Government of Qinghai Province & Beijing Normal University, Xining 810008, Qinghai, China
  • Received:2021-09-03 Revised:2022-02-22 Online:2022-05-15 Published:2022-05-30
  • Contact: Guangchao CAO E-mail:heqixin0504@163.com;Caoguangchao@qhnu.edu.cn

Abstract:

In this paper, 59 sets of samples from different water bodies such as lake water, river water, groundwater, well water, and snow in the Xiangride-Qaidam River Basin were used to measure δ2H and δ18O of indoor samples; analyze their characteristics; and explore their influencing factors, deuterium excess parameter values, and river water variation along the river. Results show that (1) the hydrogen and oxygen isotope characteristics of the water bodies in the Xiangride-Delta River Basin are different. In addition, the enrichment of δ18O during water cycle is presented in the following order: lake water > ice > groundwater > river water > well water > snow. River water and groundwater are closely linked hydraulically, and the evaporation of river water and lake water is the strongest among the water bodies in the basin. (2) The maximum values of lake water δ2H and δ18O are observed in Hobson Lake at the bottom of the basin, and the minimum values are observed in the upper east branch of the river water collected from winter to the wrong lake. It shows that the δ2H and δ18O of lake water in the northern part of the Qinghai-Tibet Plateau are more positive than those in the south, and there is an obvious elevation effect. (3) Moreover, a significant linear relationship is found between river water δ2H and δ18O: δ2H = 4.93 δ18O - 29.6 (R2=0.97). The enrichment of hydrogen and oxygen isotope components is primarily controlled by the influence of river evaporation; strong evaporation effect in the upper reaches of the river; and high deuterium excess caused by high altitude, low temperature, and low air humidity. (4) Compared with water, the depletion of hydrogen and oxygen-stable isotopes in ice at the same location results from repeated evaporation and condensation of local water vapor.

Key words: hydrogen and oxygen isotope, deuterium excess parameter, precipitation line, isotopic effect, Xiangride-Qaidam River Basin