Factors Influencing Soil Erosion on Roadbed Side Slope in Southwest Hubei Province

In order to study soil erosion processes and their influence factors on roadbed side slope,the roadbed side slope of Hurongxi expressway from Enshi to Lichuan located in Southwest Hubei Province was taken as a study object.The analysis of main factors of soil erosion on the roadbed side slope was carried based on soil erosion observation under the natural rainfall condition.The analysis indicates that rainfall process was the most important factor influencing soil erosion and as a whole the effects of rainfall amount,rainfall duration,and rainfall intensity on soil erosion were relatively similar.On a relatively gentle slope,the influence of rainfall amount was greater than that of rainfall intensity,but on a relatively steep slope,the influence of rainfall intensity was greater than that of rainfall amount.Taking the time as change sequence,the factors influencing soil erosion were in such an order of rainfall soil moisture content vegetation degree of coverage.Soil erosion did not have a remarkable correlation with slope length and gradient,but was more sensitive to the change in gradient.