The Effect of Vegetation Restoration on Erosion Processes and Runoff on a Hillslope Under Simulated Rainfall

Determining the impact of vegetation restoration on runoff and sediment yield is crucial for formulating science-based slope management practices. The study analyzed runoff and sediment yield behavior in relation to varying vegetation cover and components, based on field-simulated rainfall experiments. The results showed that both runoff and sediment yield rates tended to decrease as vegetation cover increased. Vegetation contributed more significantly to the reduction in sediment yield than to the reduction in runoff. For a rainfall intensity of 1.5 mm·min−1, the sediment yield reduced to 37%, 73%, 78%, and 94% under the vegetation coverage of 20%, 40%, 60%, and 90%, respectively. The corresponding sediment yield reduction effects at the rainfall intensity of 2.0 mm·min−1 were 27%, 67%, 78% and 89%, respectively. At a rainfall intensity of 1.5 mm·min−1, the sediment yield reduction contributions of the litter layer, stem-leaf layer, and roots were 36%, 3%, and 51%, respectively. The corresponding sediment yield reduction contributions at the 2.0 mm·min−1 rainfall intensity were 30%, 7%, and 51%, respectively.