Study on the Ecological Restoration of Saline-alkali Soils Lands in the Shrinkage Area of Plateau Inland Lakes: A Case Study of Dalinor Lake in Inner Mongolia

Climate change and human activities tend to cause the shrinkage of lakes in arid areas, thus affecting regional ecological security. In recent years, biodiversity conservation and ecological restoration in lake shrinking areas have attracted significant attention. To explore the factors of ecological restoration in the shrinkage areas of plateau lakes under global climate change, a case study was carried out in Dalinor Lake in Inner Mongolia. Soil pH, nutrients, and revegetation effectiveness of different ecological restoration sites, including bare land near the lake, Suaeda heteropteran planted area, wetland restored area, and revegetated sandy land, were compared. The adaptation strategy of "climate change-lake shrinking-ecological restoration" was also discussed. The results show that: (1) soil pH values and fertility in the lake shrinking areas were higher than those in revegetated sandy lands. Some soil nutrient indicators improved with the increase in elevation and distance from the lake shoreline. Compared with bare land near the lake, the total carbon, total nitrogen, and total potassium contents in the Suaeda heteropteran planted area and wetland restored area increased significantly. (2) The revegetation effectiveness in the shrinking area of Dalinor Lake has achieved remarkable results, with a gradual increase in vegetation coverage and plant number along the direction of "bare land near the lake-Suaeda heteropteran planted area-wetland restored area" perpendicular to the shoreline of the lake. (3) The saline-alkaline soil produced after the shrinkage of lakes in arid regions is difficult for plants. Revegetation indicators were significantly correlated with soil total carbon (TC), total nitrogen (TN), and organic matter (SOC) contents. The revegetation countermeasures of saline-alkali lands in lake shrinking areas should be classified according to the main functions of ecological restoration zones. The research findings could provide references for strengthening the adaptive management of climate change risks and ecological function restoration for shrinking lakes in dry areas.