Effects of soil deformation on clay dispersion in loess soil

All the measurements were done with soil from the plough (5-20 cm) and subsoil (25-35 cm) layers. The amount of RDC increased with increasing deformation level and depth. In the plough layer this increase was from 0.786 under NC to 1.216 g 100 g−1 under SC. Corresponding values in the subsoil layer were 1.227 and 1.874 g 100 g−1. Positive correlations were found between readily-dispersible clay and bulk density in both the plough (R2 =0.685) and the subsoil layers (R2 =0.332). The results for clay dispersion are discussed in relation to the different contents of organic carbon in the plough and subsoil layers and the potential mechanisms of soil vulnerability to soil erosion, crusting and deformation.