The series of overland flow experiments were conducted on flexible vegetative beds with 20 degree slopes,and the hydraulic characteristics of sheeted flows were observed for parameters such as surface velocity,flow depth,and the averaged velocity.The local head losses was also calculated.The results showed that the mechanism of flow resistance presents very obvious differences because of the effects of hydraulic jump and aeration on the overland flow around flexible vegetation.The fitting relations showed an exponential function and curve of the second degree,respectively.In addition,the surface flow velocity was made by means of dye-color method,the relationship between surface velocity and averaged velocity was discussed,and the revised coefficient of 0.23 with the distributions of flexible vegetation was obtained.
