Modeling and assessing the impacts of climate change on groundwater recharge in endorheic basins of Northwest China

Wenju Cheng; Qi Feng; Haiyang Xi; Xinwei Yin; Lei Cheng; Celestin Sindikubwabo; Baiting Zhang; Yuqing Chen; Xinyue Zhao

doi:10.1016/j.scitotenv.2024.170829

Modeling and assessing the impacts of climate change on groundwater recharge in endorheic basins of Northwest China

Sci Total Environ. 2024 Mar 25:918:170829. doi: 10.1016/j.scitotenv.2024.170829. Epub 2024 Feb 8.

Authors

Wenju Cheng¹, Qi Feng², Haiyang Xi³, Xinwei Yin³, Lei Cheng⁴, Celestin Sindikubwabo⁵, Baiting Zhang¹, Yuqing Chen¹, Xinyue Zhao¹

Affiliations

¹ Key Laboratory of Ecohydrology of Inland River Basin, Qilian Mountains Eco-environment Research Center in Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
² Key Laboratory of Ecohydrology of Inland River Basin, Qilian Mountains Eco-environment Research Center in Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China. Electronic address: qifeng@lzb.ac.cn.
³ Key Laboratory of Ecohydrology of Inland River Basin, Qilian Mountains Eco-environment Research Center in Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
⁴ State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China.
⁵ College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China.

PMID: 38340856
DOI: 10.1016/j.scitotenv.2024.170829

Abstract

Climate change imposing additional stressors on groundwater resources globally, thereby predicting groundwater recharge (GR) changes is crucial to sustainably managing water resources, especially in the arid endorheic basins. Groundwater in the Endorheic Basins of Northwest China (NWEB) is potentially impacting regional socio-economic output and ecosystem stability due to the imbalance between supply and extraction exacerbated by climate change. Hence, recognizing the impacts of climate change on past and future GR is imperative for groundwater supply and sustainable groundwater management in the NWEB. Here, the impact of historical (1971-2020) and projected (2021-2100) climate changes on GR across the entire NWEB and three distinctive landscape regions (i.e., mountainous, oasis, and desert) were assessed. A coupled distributed hydrologic model (CWatM-HBV model), which integrates the Community Water Model (CWatM) and the HBV model, was run with three shared socioeconomic pathways (SSP1-2.6, SSP2-4.5, and SSP3-7.0) forcing from 10 general circulation models (GCMs) to simulate and analyze the interannual and seasonal variations of GR, along with their driving factors. Over the past 50 years, both precipitation and runoff have undergone significant increases, and leading to a dramatic rise in GR (0.09 mm yr^-1). The future annual growth rate of GR is projected to range from 0.01 to 0.09 mm yr^-1 from SSP1-2.6 to SSP3-7.0 across the entire NWEB, with the majority of the increase expected during the spring and summer seasons, driven by enhanced precipitation. GR from the mountainous region is the primary source (accounting for approximately 56-59 %) throughout the NWEB with the greatest increase anticipated. Precipitation and runoff have significant influences on GR in mountainous areas, and the impact of precipitation on GR is expected to increase over time. Changes in GR in oasis and desert areas are mainly limited by precipitation variation and increase in the SSP2-4.5 and SSP3-7.0 scenario. Additionally, the processes of glacial retreat and permafrost degradation will complicate the GR dynamics although the process is largely interfered with by anthropogenic environmental changes, especially in oasis-desert systems. The average annual recharge in the NWEB was 8.9 mm in the historical period and 13.6 ± 4.1 mm in the future. Despite an increase in GR due to climate change, groundwater storage is likely to continue to decline due to complex water demands in the NWEB. This study highlights the significance of future precipitation changes for GR and contributes to the understanding of the influence of climate change on groundwater systems and advances the sustainable management of water resources.

Keywords: CWatM-HBV model; Climate change; Endorheic basins of Northwest China; Groundwater recharge.