Modeling of soil redistribution by sweeps

Soil translocation due to tillage resulting in increased soil erosion has been an ongoing problem in crop production. Developing physically based mathematical models to describe soil redistribution by tillage tools is very important for both designing new tools and managing tillage practices. Based on the model developed fora single sweep in previous study, a model of soil redistribution by multiple sweeps was developed and validated with soil bin experimental results. The model can describe lateral soil redistribution and mixing during tillage, and calculate the geometrical parameters of soil profile. Tillage depth and speed, a soil strength parameter, and tool geometrical parameters were the variables involved in this model. The effect of surface crop residue on soil redistribution was indirectly involved through average lateral soil displacement. Tests were conducted in an indoor soil bin using a 325-mm-wide sweep to validate this model. Soil translocation and redistribution after tillage operation with three parallel passes of a single sweep were measured at the speeds of 5, 7.5, and 10 km/h respectively. The comparison of measured and predicted results indicated that the model would predict soil redistribution by tillage operation using multiple sweeps in the speed range of 5 km/h to 10 km/h. The relative error of the model prediction was below 27 percent compared to the experimental results. A possible lateral soil translocation on a plane field was quantitatively explained using this model.