Soil displacement and tillage erosion during secondary tillage operations: the case of rotary harrow and seeding equipment

This study reports the results of a series of experiments that were set up on agricultural land in central Belgium to investigate soil translocation and erosivity resulting from a secondary tillage operation using an implement sequence of a rotary harrow and seeder. Aluminium cubes were used as tracers of soil movement. Results show that soil displacement resulting from tillage with such an implement sequence is far from insignificant. This is mainly related to the relatively shallow tillage depth as well as to the loose initial soil condition of such secondary tillage operations. The calculated value for the tillage transport coefficient k (123 kg m−1 per tillage operation) is comparable with k-values from implements that are considered to be more erosive, like mouldboard and chisel implements. In conclusion, this study shows that tillage erosion not only results from relatively aggressive tillage operations such as mouldboard and chisel passes, but that secondary operations contribute significantly to soil displacement and tillage erosion.