Effects of Polyacrylamide on Runoff and Sediment Characteristics of Slope in Northeast Black Soil Area

Abstract

Soil erosion caused by hydraulic erosion has become the main driving force to destroy the ecosystem and has become a worldwide environmental problem. The effect of polyacrylamide (PAM) on slope erosion characteristics in black soil area was studied under different conditions. The method of artificial simulation of rainfall was adopted. At 4 slopes and 5 PAM concentrations, the rainfall lasted 60min and the rainfall intensity was 80mm/h. The results show that when the rainfall intensity and underlying surface conditions are the same, the slope increases from 10° to 25°, the average runoff on the slope increases first and then decreases, and the sediment yield increases with the increase of the slope. The sediment yield on the 25° slope is 1.64 times that of the 10° slope. With the same rainfall intensity and slope compared with bare land, the concentration of Polyacrylamide in 2g / m2 increased to 5g / m2, and the average yield decreased by 10.6% to 20%. The average sediment yield decreased with the increase of the concentration, which was 20.4%∼52.5% lower than that of the bare land. The variation law of PAM and bare slope sediment yield can be described by power function. Compared with the total sediment yield of PAM and bare slope, PAM is obviously decreased. The bare slope surface is mainly characterized by splash erosion and surface erosion. The application of PAM can reduce the erosion area of slope compared with bare slope, which plays an important role in corrosion prevention.