Abstract:The objective of this study was to investigate the law of runoff and sediment yielding from original and disturbed sites in the Shenfu-Dongsheng coalfield by a simulated rainfall experiment. Results showed that the time for runoff initiation in disturbed sites was 1.8 to 11.7 times that in original sites. However, runoff rate for disturbed sites was 5% to 54.4% less than that for original sites. The initial sediment concentration, average sediment concentration and sediment yield in disturbed sites were 1.1 to 5.8, 1.2 to 6.3, and 2 to 12.7 times of those in original sites, respectively. Runoff and soil erosion in disturbed sites occurred under high intensive rainfall because of lower bulk density, higher porosity and greater infiltration rate as compared with original sites. Once erosion began, disturbed sites were subject to erosion under the same rainfall condition due to smaller critical shear resistance and could result in larger erosion rate. It was found by regression analysis, there existed a linear relationship between sediment yield and flow shear stress.