An Analysis on the Characteristics and Influence Factors of Soil Salinity in the Wasteland of the Kashgar River Basin

Clarifying the salt ion composition characteristics and the influence factors of soil salinization of the wasteland in the Kashgar River Basin is of high importance for saline land improvement and utilization in this region. We studied the characteristics and influence factors of soil salinity in the wasteland of the Kashgar River Basin through classical statistics, principal component analysis and grey relational theory. The results showed that the total salt content had a T-shaped distribution pattern in the soil profile. As the most important ions, Cl⁻, Na⁺, and SO₄²⁻ have the characteristics of vertical differentiation from top to bottom in the soil profile. Correlation analysis showed that the total salt content was negatively correlated to the HCO₃⁻ content and positively correlated to other salt ions, The most correlated anions were SO₄²⁻ and Cl⁻. Na⁺, the most important cation, had the closest relationship with Cl⁻, followed successively by SO₄²⁻ and HCO₃⁻. Principal component analysis showed that SO₄²⁻, total salt content, Na⁺, Cl⁻, Mg²⁺, and Ca²⁺ could represent soil salinity status and salt ion composition, while HCO₃⁻ could represent soil alkalization status. The grey relational analysis indicated a differentiation in the intensity of influence of each factor on soil salinization at different depths. Except for groundwater burial depth and elevation, the relational degree between other influence factors and soil salt content decreased with depth. Our research findings offer important clues for understanding the soil salinity characteristics and influence factors of salinization in the wasteland of the Kashgar River Basin.