Compounding effects of human activities and climatic changes on coexistence of oasis-desert ecosystems:Prioritizing resilient decision-making for a riskier world

作     者：XinWei Yin Wei Liu Meng Zhu JuTao Zhang Qi Feng HaiYang Xi LinShan Yang Tuo Han WenJu Cheng YingQing Su BaiTing Zhang YuanYuan Xue ZeXia Chen LingGe Wang XinWei Yin;Wei Liu;Meng Zhu;JuTao Zhang;Qi Feng;HaiYang Xi;LinShan Yang;Tuo Han;WenJu Cheng;YingQing Su;BaiTing Zhang;YuanYuan Xue;ZeXia Chen;LingGe Wang

作者机构：Key Laboratory of Ecohydrology of Inland River BasinNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Key Laboratory of Desert and DesertificationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of SciencesBeijing 100049China College of Geography and Environment ScienceNorthwest Normal UniversityLanzhouGansu 730070China 

出 版 物：《Research in Cold and Arid Regions》 (寒旱区科学（英文版）)

年 卷 期：2023年第15卷第5期

页      面：219-229页

核心收录：

学科分类：07[理学] 09[农学] 0705[理学-地理学] 0903[农学-农业资源与环境] 0713[理学-生态学] 

基　　金：supported by the National Key R&D Program of China(2022YFF1303301) the National Natural Science Foundation of China(52179026,42101115,41901100,32301671) the China Postdoctoral Science Foundation Project(2022M720162) the XPCC Science and Technique Foundation(2021AB021) 

主　　题：Oasis-desert ecosystems Hydrological regimes Soil salinization Vegetation dynamics Resilient decision-making 

摘      要：Water-salt balance is critical for the stable coexistence of salt-affected and groundwater-fed oasis-desert ecosystems. Yet, a comprehensive investigation of how soil salinization and groundwater degradation threaten the coexistence of oasis-desert ecosystems is still scarce, especially under the compounding effects of human activities and climatic changes. Here, we assessed the impacts of irrigated agriculture on hydrological regimes in oasisdesert systems, investigated the spatio-temporal variations of soil salinization in irrigated cropland, and evaluated the implications of the interplays of soil salinization and groundwater degradation on the coexistence of oasis-desert ecosystems in northwestern China, based on meaningful modelling approaches and comprehensive measurements over 1995–2020. The results showed that the irrigation return flow coefficient decreased sharply from 0.21 ± 0.09 in the traditional irrigation period to 0.09 ± 0.01 in the water-saving irrigation period. The continuous drop in groundwater tables and significant degradation of groundwater quality are occurring throughout this watershed. The eco-environmental flows are reaching to their limit with watershed closures(i.e.,the drainage from the oasis region into the desert region is being weakened or even eliminated), although these progressions were largely hidden by regional precipitation and streamflow variability. The process of salt migration and accumulation across different landscapes in oasis-desert system is being reshaped, and soil salinization in water-saving agricultural irrigated lands is accelerating with a regional average annual growth rate of18%. The vegetation in this watershed is degrading, and anthropogenic disturbance accelerates this trend. Our results highlight that environmental stress adaptation strategies must account for resilience maintenance to avoid accelerating catastrophic transitions in oasis-desert ecosystems. Determining the optimal oasis scales and formulatin