Research on processes and factors of rill erosion

The erosion processes of 10 kinds of soil were studied with the experimental erosion slots and 2 artificial rainfalls with an interval of 11 hours.As a result,rill erosion has been observed in most soils during the second event of rainfall.The observations about runoff and sediment suggest that sediment concentration and runoff rate of all the soils with rill erosion decrease in the first rainfall,and increase then decrease in the second rainfall.The results of physical and chemical analysis and the multi-factor regression show that soil texture,content of soil organic matter,ferrous and aluminous compounds have an unnoticeable effect on rill erosion,while indexes of soil structure concerning soil aggregates have a close correlation with the rill erosion,the velocity and grosses of runoff and sediment.The degree of aggregate despersibility and the ratio of collapsing rate to infiltration rate work well in predicting possibility of rill erosion and the sediment discharge as well.