Abstract
In order to clarify the straw mulch effect on slopes steeper than 18X, soil losses were measured for three rates of straw mulch and four stages of slope steepness. Mulch applied at a rate of 1 ton/lOa greatly reduced soil erosion 0.073% as compared with no mulch. Both soil loss and water runoff from soybean — planted slopes with mulch were almost constant with the increase of slope steepness, nevertheless soil losses per unit area of bare slopes increased as the 2.6 power of the slope steepness. Straw mulch reduced the surface runoff and controlled the rill erosion on the slopes with the steepness between 18% and 44%.
