An interplay of soil salinization and groundwater degradation threatening coexistence of oasis-desert ecosystems

Xinwei Yin; Qi Feng; Yan Li; Ravinesh C Deo; Wei Liu; Meng Zhu; Xinjun Zheng; Ran Liu

doi:10.1016/j.scitotenv.2021.150599

An interplay of soil salinization and groundwater degradation threatening coexistence of oasis-desert ecosystems

Sci Total Environ. 2022 Feb 1;806(Pt 2):150599. doi: 10.1016/j.scitotenv.2021.150599. Epub 2021 Sep 27.

Authors

Xinwei Yin¹, Qi Feng², Yan Li³, Ravinesh C Deo⁴, Wei Liu⁵, Meng Zhu⁵, Xinjun Zheng⁶, Ran Liu⁶

Affiliations

¹ Key Laboratory of Ecohydrology of Inland River Basin, 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, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China. Electronic address: qifeng@lzb.ac.cn.
³ State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, Xinjiang, China. Electronic address: liyan2016@zafu.edu.cn.
⁴ School of Sciences, Centre for Applied Climate Sciences, Centre for Sustainable Agricultural Systems, Institute for Life Sciences and the Environment, University of Southern Queensland, Springfield, 4300, Australia.
⁵ Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
⁶ Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, Xinjiang, China; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.

PMID: 34592278
DOI: 10.1016/j.scitotenv.2021.150599

Abstract

In salt-affected and groundwater-fed oasis-desert systems, water and salt balance is critically important for stable coexistence of oasis-desert ecosystems, especially in the context of anthropogenic-induced over-development and perturbations due to climate variability that affects the sustainability of human-natural systems. Here, an investigation of the spatio-temporal variability of soil salinity and groundwater dynamics across four different hydrological regions in oasis-desert system is performed. An evaluation of the effects of soil salinization and groundwater degradation interplays on the coexistence of oasis-desert ecosystems in northwestern China is undertaken over 1995-2020, utilizing comprehensive measurements and ecohydrological modelling framework. We note that the process of salt migration and accumulation across different landscapes in oasis-desert system is reshaping, with soil salinization accelerating especially in water-saving agricultural irrigated lands. The continuous decline in groundwater tables, dramatic shifts in groundwater flow patterns and significant degradation of groundwater quality are occurring throughout the watershed. Worse so, a clear temporal-spatial relationship between soil salinization and groundwater degradation appearing to exacerbate the regional water-salt imbalance. Also, the eco-environmental flows are reaching to their limit with watershed closures, although these progressions were largely hidden by regional precipitation and streamflow variability. The oasis-desert ecosystems tend to display bistable dynamics with two preferential configurations of bare and vegetated soils, and soil salinization and groundwater degradation interplays are causing catastrophic shift in the oasis-desert ecosystems. The results highlight the importance of regional adaptive water and salt management to maintain the coexistence of oasis-desert ecosystems in arid areas.

Keywords: Adaptive water-salt management; Groundwater dynamics; Interplay; Oasis-desert ecosystems; Soil salinization.

MeSH terms

Agriculture
China
Ecosystem
Groundwater*
Humans
Salinity
Soil*

Substances

Soil