The matural sloping face of different gradient slope in the hilly region in south of Ningxia after changing sloping field were experimentally studied by means of artificial rainfall simulation. The results showed that the rainfall intensity were in inverse ratio to supplement soil conserving water

infiltration depth were reduced with the increase of gradient. The effect of artificial rainfall simulation and doubt ring method to steady infiltration rate were compared

the soil steady penetrating velocity measured by artificial rainfall was less than one measured by two loop method

and there were linear function relationship between two values. The water supplement to level trench increased with the increase of the gradient and rainfall intensity

the downfall were significant to the water supplement to level trench. The analysis of sediment yield dynamics showed that the sediment content per volume descended with time process under bigger rainfall intensity

while increased by degrees under smaller rainfall intensity. The relationship of rainfall power and soil erosion modulus accorded with the power function equation:Q=0.017 I~(2.5442)