HESSD Hydrology and Earth System Sciences Discussions HESSD Hydrol. Earth Syst. Sci. Discuss. 1812-2116 Göttingen, Germany 10.5194/hess-2022-75 Evaporation loss estimation of the river-lake continuum of arid inland river: Evidence from stable isotopes Zhu Guofeng https://orcid.org/0000-0003-0572-7041 1 2 Sun Zhigang 1 2 Xu Yuanxiao 1 2 Liu Yuwei 1 2 Zhang Zhuanxia 1 2 Sang Liyuan 1 2 Wang Lei 1 2 College of Geography and Environment Science, Northwest Normal University, Lanzhou 730070, Gansu, China Shiyang River Ecological Environment Observation Station, Northwest Normal University, Lanzhou 730070, Gansu, China National Natural Science Foundation of China 41867030, 41971036 22 04 2022 2022 1 33 Copyright: © 2022 Guofeng Zhu et al. 2022 This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/ This article is available from https://hess.copernicus.org/preprints/hess-2022-75/ The full text article is available as a PDF file from https://hess.copernicus.org/preprints/hess-2022-75/hess-2022-75.pdf

<p>Stable isotopes could be used as tracers to estimate the evaporation loss of surface water, which provides a new perspective for the research of hydrological processes. A systematic observation station has been built in the Shiyang River Basin, one of the most important inland river basins in Northwest China. This work conducted systematic observations on the river water, precipitation and hydrometeorology of the Shiyang River from 2017 to 2019. The evaporation loss of the Shiyang River is estimated to be 1.30 % in the mountainous rivers, 2.28 % in the mountainous reservoir (Xiying Reservoir), 2.87 % in the oasis rivers, 7.97 % in the oasis reservoir (Hongyashan Reservoir), and 41.37 % in the terminal lake (Qingtu Lake). No matter in mountain or oasis, the evaporation loss of reservoir is much higher than that of the river, and the evaporation loss of the terminal lake is the largest. The evaporation loss of the river-lake continuum accounts for 14.66 % of the total water volume of rivers and lakes (reservoirs). This work enriches the study of stable isotopes in the field of evaporation loss in the river-lake continuum, expands our understanding of the hydrological cycle in arid regions.</p>