Influence of simulated erosion on soil properties and maize yield in Northwestern India

Abstract

Laboratory and field experiments were conducted at the Regional Research Station of Kandi Area, Ballowal Saunkhri, Punjab, India, to determine the immediate influence of artificial topsoil removal (simulated erosion) on selected soil properties, maize (Zea mays) growth and yield, and restoration of crop productivity with nitrogen (N) fertilization. For the laboratory experiment, soil samples (0–15 cm) were obtained after removing 0, 6, 12, and 18 cm of a sandy loam topsoil from a cereal grain cropped field. In the field experiment, topsoil was removed at 0, 6, 12, and 18 cm in main plots, and six N treatments at rates of 0, 40, 80, 120, 160, and 200 kg N ha^‐1 were applied in subplots. Topsoil removal greatly decreased mineralized N, N mineralization potential and rate constant, and increased time for half mineralization of N. Bulk density and penetration resistance increased as a result of topsoil removal and infiltration capacity of the soil decreased. Total profile water was more at the time of harvest than at sowing in the plots where topsoil was removed, but the water expense efficiency decreased. Both grain and straw yield of maize decreased substantially as a result of adverse effect of topsoil removal on plant height, mass and depth of root, length and girth of cob, and thousand grain weight. Nitrogen application improved maize growth and yield, but the crop responded to higher doses of N on eroded plots than the uneroded plots, and yields on eroded plots did not match to those obtained on uneroded plots at any level of N application. In conclusion, artificial surface soil erosion deteriorated soil properties governing maize productivity. More N was required where topsoil had been eroded, but N application alone did not restore crop yield to that level obtained from uneroded soil. Therefore, there is a need to look for and quantify other factors also to improve soil productivity.