Effects of soil cover and protective measures on reducing runoff and soil loss under artificial rainfall

The hazards from wind, sand, and soil erosion caused by human activities, such as residue slopes in abandoned urban mines, have resulted in a vicious circle of environmental degradation. Selecting the optimal protective engineering method in mountainous areas has become a major difficulty in recent years, and the primary goal of our research is to accelerate the process of ecosystem reconstruction to maintain water and soil quality. In this study, cover soil of 10, 20, and 30 cm in depth was spread on the 30° accumulation slopes composed of loose residue from the Huangyuan Quarry, Beijing, and combined with two protection measures: eco-bags and bamboo fences. Runoff and soil loss from the aboveground, soil and residue layers were measured under rainfall intensities of 30, 60 and 120 mm/h generated with a rainfall simulator. The results indicated that both eco-bags and bamboo fences decreased runoff and soil loss. Bamboo fences were better at intercepting water under low runoff, whereas soil loss was more strongly reduced by eco-bags. The analysis also demonstrated that the depth of soil cover had an effect on runoff and soil loss. These findings will enrich the understanding of the effects of human activities on surface mines and provide a scientific basis for the ecological restoration of mines using engineering methods.