Abstract:As sheet erosion has spatial variations along slope,it is important for the improvement of soil erosion theory to explain soil erosion process on different segments of a hillslope.Sheet erosion characteristics on downslope were analyzed based on experiments of simulated rainfall with multiple plots.The results show that the sheet erosion characteristics on the down slopes differed from those on the whole slopes and upslopes.The sheet erosion on downslopes displayed extremely strong variability.The sheet erosion rates fluctuated with rainfall course,rainfall intensity,and slope gradient.Generally,it increased with the increased time at beginning and then stabilized.The rate increased with slope gradient and rainfall intensity.The variation of sheet erosion modulus with rainfall intensity and slope gradient can be described by a duality linear equation and rainfall intensity affected sheet erosion modulus much greater than slope gradient.The impact of runoff from both upslope and downslope and sediment from upslope on downslope sheet erosion were described by a duality linear equation,with contributions of 56.9%and 25.4%,respectively.Runoff had a greater effect than sediment.It can effectively control sheet erosion on downslope to take measures such as increasing the infiltration and reducing runoff