The Impact of Salinization and Wind Erosion on the Texture of Surface Soils: An Investigation of Paired Samples from Soils with and without Salt Crust

Abstract

Wind erosion removes fine soil particles and thus affects surface soil properties, but the existence of a salt crust could prevent wind erosion and protect fine soil particles. Such results referring to wind erosion affecting soil surface textural properties have been reported by many studies. However, it is still not clear whether soil properties differ between salt-crusted soils and adjacent soils without a salt crust in areas experiencing serious wind erosion. Therefore, the objective of this study was to investigate paired samples from salt-crusted and non-crusted surface soils at 23 sites in the Tarim River Basin. The particle size distribution, salt content and composition, and crust thickness and strength were determined. The results of the pooled t-test reveal that, compared with soils without a salt crust, the salt-crusted soils had finer particles (silt + clay), but this difference only occurred in paired soils from the same site, and the silt content showed the largest difference between the paired soils. The salt content and salt crust strength showed great variability, from 88.52 to 603 g·kg−1 and from 0.30 to 5.96 kg·cm−1, respectively, at all sites, but only a weak relationship (R2 = 0.396) between the salt content and crust strength was found, indicating that the salt content was not the only factor affecting crust strength. Our results suggest that wind erosion and salinization cause great soil texture spatial heterogeneity, especially for silt particles in the Tarim River Basin. Variation in salt crust strength can influence dust emissions and must be considered in future management.