Effect of Underground Coal Mining on Slope Morphology and Soil Erosion

Table 9

Erosion modulus (M_s) and runoff modulus (M_w) of different natural slope gradient before and after mining.

Slope gradient	Before mining		After mining		Variation
	Ms (t·km^−2)	Mw (t·km^−2)	Ms (t·km^−2)	Mw (t·km^−2)	Ms (t·km^−2)	Mw (t·km^−2)
0°	0	0	2.854	374.214	2.854	374.214
5°	7.252	930.107	8.470	1082.184	1.218	152.077
10°	12.121	1535.245	13.029	1647.697	0.909	112.452
15°	16.369	2058.219	17.074	2145.470	0.705	87.251
20°	20.258	2534.092	20.832	2605.101	0.575	71.010
30°	27.357	3397.319	27.695	3439.962	0.337	42.643