Balance of water supply and consumption during ecological restoration in arid regions of Inner Mongolia, China

Abstract Water shortage is a critical obstacle to socioeconomic development and ecological restoration in arid regions. In this study, soil-vegetation water use was calculated, and a system dynamic model that coupled economic, societal, and ecological factors was developed to simulate the water-use structure in the Alxa League of China's Inner Mongolia Autonomous Region. The results showed that the soil–vegetation system water use in Alxa was approximately equal to precipitation and showed a water-balance status; however, more than 50% of the vegetation areas were undersupplied by rainwater. The model indicates that the disparity between water supply and consumption in Alxa is likely to increase over the next 15 years. If priority were given to expanding ecological land, such as greatly increasing the area of desert psammophytes, less than 86% of the demand for water resources could be met, which would result in insufficient water supply for production. Water supply and consumption would only be balanced in water-saving-optimization scenarios, which could provide 90 million m3 of excess water for ecological restoration. Therefore, it is necessary to carefully choose plantation sites based on their water-balance status, appropriately control the scale of ecological land, and adopt effective water-saving measures in industrial and agricultural production.