Effect of Tillage Treatments and Off-Road Vehicle's Operating Parameters on Soil Physical Properties

Changes in soil physical properties (bulk density, cone penetration resistance, and infiltration rate) were used to investigate the effect of three different vehicle parameters. These parameters include tillage treatments (no-till, rotary tillage, and moldboard plowing), axle load (loaded and unloaded grain cart), and tire inflation pressure (high and low inflation pressures). Soil response to these parameters was measured between 0-480 mm depth. The results obtained from the experimental data showed that dry bulk density and cone penetration resistance were affected from 0-240 mm depth by axle load and tillage treatments. However, dry bulk density and cone penetration resistance were affected from 240-480 mm depth by tire inflation pressure and axle load. The loaded vehicle with high tire inflation pressure on no-till plot had the greatest effect while, the unloaded vehicle with low tire inflation pressure on rotary tilled plots had the lowest effect. In general, the results of soil penetration resistance showed similar trends as with dry bulk density but, the percentages were different. Finally, it was found that infiltration rate was highly affected by tillage treatments at the tillage depth.