Characteristic of Runoff-Sediment Yield and Runoff Simulation on Hillslope in Northern Shaanxi

The rules of sediment and runoff using field simulated rainfall trails.The results show that: the runoff on barren land were 1.15,1.46 and 2.64 times greater than that on grass land and PAM land and straw mulch land,the sediment production on barren land were 1.3,1.5 and 44.4 times greater than that on grass land and PAM land and straw mulch land in the same rainfall intensity,and straw mulch was better than the others on the effect of soil and water conservation;cumulative sediment linearity increase with cumulative runoff,they had perfectly correlativity and correlation coefficient above 0.95;It simulates the measured runoff based on the short duration of runoff modified model.The simulations results indicated that the modified Philip model is be apply to predict runoff on bare land,grass land,PAM land which calculated and measured values within 10% to meet the accuracy requirements,however,it need further study because it is not flexible for the straw mulch.The soil absorption parameters of methods to estimate rates of S applied to the grass and PAM to get the relationship between the soil conductivity of and saturated hydraulic conductivity: grassland K=0.90KS,PAM land K=0.98KS.This study had a great significance to the choices of soil and water conservation measures.