Soil salinization has posed a great threat to agricultural production and regional development in irrigation districts of arid regions with shallow groundwater tables. Therefore, it is highly demanding to assess the soil salinization-alkalization for rational regulation of soil water and salt regime in high-efficient utilization of water and land resources. In this study, an attempt was made to evaluate the spatial distribution pattern of soil salinization in the farmland of the Wulate sub-irrigation area in the lower reaches of the Hetao irrigation district in spring. An analysis of soil particle size was performed using field sampling combined with laboratory testing. The soil profiles (ground surface to groundwater level) of typical points were determined to measure the salinization indicators at 113 sampling points, including the Total Salt content (TS), pH value, contents of eight major salt ions (CO32-, HCO3-, Cl-, SO42-, Ca2+, Mg2+, and K++Na+), exchangeable Na+ content, Cation Exchange Capacity (CEC), and Exchangeable Sodium Percentages (ESP) in 0-20 cm and 20-40 cm soil layers. Classical statistics, geostatistics, and multi-index comprehensive evaluation were applied to obtain the spatial distributions of soil salinization regime using different indicators. The results showed that the content of TS in 0-20 cm soil layer was higher than that in 20-40 cm. The soluble salt ions in the soil were mainly HCO3-, SO42-, Cl-, and Na+. The spatial variability of pH value was weak with the coefficient of variation (CV) less than 10%, those of TS and contents of CO32-, Cl-, SO42- and K++Na+ were strong with CV greater than 100%, those of HCO3-, CEC, exchangeable Na+ and ESP were medium with 10%
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