Integrating satellite observations and human water use data to estimate changes in key components of terrestrial water storage in a semi-arid region of North China

Wenchao Sun; Yongliang Jin; Jingshan Yu; Guoqiang Wang; Baolin Xue; Yue Zhao; Yongshuo Fu; Sangam Shrestha

doi:10.1016/j.scitotenv.2019.134171

Integrating satellite observations and human water use data to estimate changes in key components of terrestrial water storage in a semi-arid region of North China

Sci Total Environ. 2020 Jan 1:698:134171. doi: 10.1016/j.scitotenv.2019.134171. Epub 2019 Aug 30.

Authors

Wenchao Sun¹, Yongliang Jin¹, Jingshan Yu¹, Guoqiang Wang², Baolin Xue¹, Yue Zhao³, Yongshuo Fu⁴, Sangam Shrestha⁵

Affiliations

¹ Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, College of Water Sciences, Beijing Normal University, Xinjiekouwai Street 19, Beijing 100875, China.
² Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, College of Water Sciences, Beijing Normal University, Xinjiekouwai Street 19, Beijing 100875, China. Electronic address: wanggq@bnu.edu.cn.
³ Water Environment Institute, Chinese Academy of Environmental Planning, 8 Dayanfang BeiYuan Road, Beijing 100012, China. Electronic address: zhaoyue@caep.org.cn.
⁴ Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, College of Water Sciences, Beijing Normal University, Xinjiekouwai Street 19, Beijing 100875, China; Department of Biology, University of Antwerp, Universiteitsplein 1, BE-2610, Belgium.
⁵ Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani 12120, Thailand.

PMID: 31514033
DOI: 10.1016/j.scitotenv.2019.134171

Abstract

Sustainable management strategies for water resources rely on accurate knowledge about the dynamics of hydrological processes, especially in drylands, where freshwater is the limiting factor for the development of human society and ecosystems. The populated Loess Plateau (LP) in North China is a typical semi-arid region where competition for water between people and nature is worth noting because of afforestation promoted by the Grain to Green Program. In this study, changes in key components of terrestrial water storage (TWS) in the LP were explored using a multi-satellite approach, including Gravity Recovery and Climate Experiment (GRACE) observations and Earth observations of precipitation, evapotranspiration and soil moisture. By integrating data on human water use from different sources with satellite observations, we were able to examine the mechanisms driving these changes. The results demonstrated that, according to an evaluation based on reproducing TWS computed from the regional water balance in the LP, the mascon solution of the Center for Space Research (CSR) at University of Texas at Austin performed best out of the commonly used GRACE products. Regional TWS derived from the CSR mascon solution in the LP decreased significantly for the period 2003-2015. Significant decreases were also detected for regional ground water storage (GWS) estimated by decomposing the GRACE TWS using multi-sources remote sensing data. GWS made the greatest contribution to the changes in TWS. Increased plant transpiration was one reason for the decreasing trend of GWS. Because changes in precipitation, soil moisture and water consumed by irrigation were minor at regional scales, we concluded that the increase of transpiration is driven by deep-rooted trees planted, which use the part of precipitation that previously recharged groundwater. The findings from this study are valuable for water resource management and ecological restoration in semi-arid regions with high populations.

Keywords: Afforestation; Gravity recovery and climate experiment; Irrigation; Loess plateau; Terrestrial water storage.