Soil salinity patterns reveal changes in the water cycle of inland river basins in arid zones

Abstract. Soil salinization caused by irrational water resource use seriously affects the agricultural development and ecological construction of inland river basins in arid zones, so clarifying the water cycle mechanism of salinization in inland river basins in arid zones is crucial for the ecological environment management of the basins and the rational use of water resources. Based on remote sensing and observation data, this study quantitatively analyzed the changes in soil salinity in the Shiyang River Basin from 2002 to 2022. It explored the impacts of water conservancy projects, farmland irrigation, and climate change on soil salinity. The results of the study show that: (1) the salinized area in the Shiyang River Basin is generally on the rise, and the degree of salinization is further aggravated; (2) the lower reaches of the Shiyang River are the areas with more severe salinization, and the middle and upper reaches of the river are at lesser risk of salinization; and (3) the regional salinization problem is more prominent as a result of the rise in the groundwater level around the reservoirs, the evaporation from the irrigation of the agricultural fields, and the evaporation from the downstream ecological water conveyance. Human activities have become a decisive factor in changing the salinization pattern of inland river basins, and the rational use and management of water resources have great potential to improve soil salinization.