Effects of Vegetation and Slope Gradient on Rainfall‐Induced Erosion of Reconstructed Iron Tailings Slopes: An Experimental Study

Abstract

The loose structure and steep slope of iron tailings severely limit vegetation restoration under heavy rainfall erosion. To mitigate soil and water loss from iron tailings, this study reconstructed iron tailings to create a substrate suitable for plant growth. The effects of vegetation at different growth stages and slope gradients on runoff erosion on reconstructed soil slopes were investigated, providing scientific support for optimizing slope stability and vegetation‐based ecological restoration techniques. Continuous monitoring of runoff initiation time, volume, and sediment yield enables quantitative analysis of the effects of these factors on rainfall infiltration and slope erosion. The results revealed that bare soil slopes presented average infiltration rates of 0.916, 0.891, and 0.857 mm/min, which stabilized within 9 to 12 min, with rates decreasing as the slope gradient increased. In contrast, vegetation significantly enhances infiltration; for example, on a 15° slope, the average infiltration rates for vegetated slopes at 30, 60, and 90 days were 0.923, 0.936, and 0.943 mm/min, stabilizing at 15, 24, and 27 min, respectively. Furthermore, vegetation cover effectively reduces runoff rates, with the cumulative runoff volume decreasing by 13%, 40%, and 53.2% at 30, 60, and 90 days, respectively. Vegetation also substantially suppresses soil erosion, with sediment yield reductions ranging from 12.5% to 76.56%, 11.77% to 77.57%, and 11.97% to 78.66% across various slopes. After 60 days of growth, significant improvements in runoff and erosion control were observed, providing crucial insights for soil stabilization and the advancement of vegetation‐based slope protection technologies.