Impact of incorporated residues on runoff and soil erosion in black soil under simulated rainfall

Incorporated residue cover and surface residue cover are strongly recommended in field management to control soil erosion. However, quantitative investigations on the use of incorporated residue cover for soil and water conservation were relatively fewer in the black soil region of Northeast China. Simulated rainfall experiments were conducted to compare the effects of incorporated residues on soil and runoff production with those of surface cover measures. Five biomass amounts of corn residues according to the annual yield return in 1 year were designed under different rainfall events for the laboratory experiments. A quantitative conversion relationship between the incorporated residue cover and biomass was derived based on the RUSLE. The values, representing the ratio of the area covered by a piece of residue to the mass of that residue (ha/kg) from the CROP data in RUSLE, were calibrated and compared to the given values in the model. Then, the soil loss factor of the incorporated residue cover compared with the surface cover was established. Finally, the observed runoff and soil loss for the two residue cover treatments were compared and the incorporated residue cover had a higher efficiency. Our findings calibrated the parameters from the CROP data in RUSLE by simulated rainfalls. Based on the efficiency of the incorporated residue cover and surface residue cover on soil and water conservation, combining natural field management for accurate evaluation is required for actual application.