Soil Erosion Potential of Reclaimed Mined Lands

Abstract

ABSTRACT RUNOFF and erosion from three mulch treatments were measured on a surface coal mine near Hanna, Wyoming. Treatments included no mulch, standing grain mulch and crimped straw mulch. Treatments were subjected to artificial rainfall generated by a portable rainfall simulator during three successive growing seasons. Soil loss data indicate a peak in erosion hazard during the summer following seeding of the perennial species. Soil losses were initially least on the straw mulch and greatest on the no mulch treatments although soil loss differences declined by the third season. Generally, soil loss amounts varied directly with ground cover. Runoff data from all treatments indicate a general decline in infiltration rates during the study period. Vegetation, soil loss and runoff data were used to calibrate a computer simulation model of runoff and erosion. Results obtained indicate small amounts of soil loss even for very infrequent, intense qne-hour design storms on moderate slopes regardless of mulching method. Simulations indicated that erosion hazards are highly dependent upon antecendent soil moisture conditions and the time distribution of storm intensities.