QIN Huanhuan^1,2, GAO Bai², CHEN Yiping¹, SUN Zhanxue^1,2

(1. State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, China;
2.School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, China)

Abstract: Stable isotope tracing technology is an important tool to study the river hydrological process, e.g., the source of river recharge, the interaction between river and other water bodies, the hydrological cycle process, etc. The hydrogen and oxygen isotopes of Lhasa River were determined by using the method of thermal transformation element analysis isotope ratio mass spectrometry, with the contents and spatial distribution characteristics of δD and δ18O been measured. The isotopic effects of Lhasa River were analyzed, including the relationship between the hydrogen and oxygen isotopes and the meteoric water line, the variation characteristics of hydrogen and oxygen isotopes, the variation of deuterium excess parameters, the elevation effect and the continental effect. The results indicated the hydrogen and oxygen isotopes of water body of Lhasa River showed different characteristics, which reflect the supply source, continental effect, elevation effect and other factors. As a whole, δD and δ18O in Lhasa River decrease with the increase of distance along the river. δD and δ18O are close to the global meteoric water line and the meteoric water line of the eastern Qinghai Tibet Plateau, indicating that the atmospheric precipitation is the main supply source of Lhasa River Basin. The deuterium excess parameters in Lhasa River are all greater than 10‰, and far exceed the deuterium excess parameters of the global meteoric water line, indicating that Lhasa River might be replenished by ice and snow melt water with relatively poor hydrogen and oxygen isotopes.

Key words: Lhasa River; hydrogen and oxygen isotopes; deuterium excess parameter; meteoric water line; isotopic effect

EARTH AND ENVIRONMENT Vol.49, No.3, Tot No.341, 2021, Page 277-284