在实验和对比分析的基础上 ,讨论了黄土善土结皮的一些主要物理化学性质特征。结果认为 ,结皮的形成是以细砂和粗粉砂为骨架 ,以小于 0 .0 1mm的细小颗粒填塞土壤空隙的一个物理过程 ,其腐殖质含量几乎与土壤相同 ,而碳酸钙含量则略低。结皮的坚实度与前期含水率呈负相关 ,与容重和厚度呈正相关 ,而容重与厚度间的关系较为复杂 Based on the experiments and comparative analyzes, some major physicochemical properties of loess sodic crusts are discussed. The results show that the formation of crust is a physical process of fine sand and coarse silt as the framework to fill the soil pores with fine particles smaller than 0.01 mm, the humus content is almost the same with the soil, while the content of calcium carbonate is slightly lower . The solidity of the crust was negatively correlated with the water content in the early stage, positively correlated with the bulk density and thickness, and the relationship between bulk density and thickness was more complicated