Abstract：By selecting three typical soil categories and three representative natural rainfalls in southern red soil erosion area,we studied the regularity of the runoff and sediment yield and compared the soil particle composition before and after the rainfalls under the same testing conditions. Under the same erosion conditions, runoff of three types of soil followed the order of purple soil > granite red soil > quaternary red clay, and the sediment yield ranked as granite red soil > purple soil > quaternary red clay. Comparison of particle composition on the soil surface before and after rainfalls revealed that the dimension of three types of particles on the surface had a tendency of increasing. Loss of a large amount of fine particles is the major cause of soil degradation and ecological deterioration.
2014, Vol. 12 
