Effects of some soil tillage implements on soil surface roughness.

Surface roughness is one of the main important characteristics for evaluating the soil tillage performance, especially in intensive cultivated soils, for preparing seedbeds and controlling runoff and soil erosion. In this study, effects of primary soil tillage implements such as; moldboard plough (KP) and chisel plough (CP) and some of its combinations along with chosen secondary soil tillage implements at two different working speeds (0.6 m/s; 1.2 m/s) on soil surface roughness under heavy textured soil condition were investigated. Besides, moldboard plough (KP) and chisel plough (CP), its combination with disk harrow (KPD), chisel plough+(2×discharrow (CPD)) and moldboard plough+(2×discharrow+2×rotary tiller (KPDTF)), chisel plough+(2×discharrow+2×rotary tiller (CPDTF)) applications were also investigated. Soil surface roughness was determined according to chain method developed by Saleh (1993) as perpendicular and parallel to the direction of tillage. The maximal soil surface roughness in both applications to the direction of tillage was obtained at the KP application. Minimal soil surface roughness with parallel direction of tillage was occurred at KPDTF while the perpendicular was obtained in CPDTF application. It was found that the effect of two different working speeds on soil surface roughness in both tillage directions was not statistically significant.