Soil Salinization Characteristics and Multi-factor Risk Assessment in an Arid Lakeshore Zone: A Case Study of Chaiwopu Lake, Xinjiang, China

Abstract

Drylands are highly vulnerable to salt accumulation, particularly near shrinking inland water bodies where strong evaporation, shallow groundwater, and terrain interact. To quantify this process, 39 surface samples (0–20 cm) were collected from a 94.18 km² belt surrounding Chaiwopu Lake, and nine indicators—ESP, pH, slope, aspect, distance to the lake, groundwater-level decline, Simpson’s diversity index, vegetation coverage, and elevation—were integrated into a composite index. Correlation analysis, multiple linear regression, and GIS interpolation were used to map total dissolved salts and identify dominant controls. Shoreline soils were mainly moderately to severely affected, with saline and highly saline classes accounting for 45.56% of the area. High and very high classes occupied 33.47% and 45.97%, respectively, indicating basin-scale land degradation. The model explained 85.2% of the variance in total dissolved salts (R² = 0.852) and showed a strong positive relationship between the composite index and observed conditions (r = 0.801). Vegetation diversity, elevation, and vegetation coverage were the most influential factors. This framework provides a practical basis for zoning priorities for water regulation, amendment application, and ecological restoration in inland dryland basins.