Performance of an Integrated Vertical Tillage–Seeding System in Headland and Field Zones Under Conservation Agriculture

With the growing need for sustainable soil management, conservation tillage technologies are becoming increasingly important for maintaining favorable soil physical conditions while reducing the environmental impact of field operations. However, reduced soil disturbance may alter soil physical properties, particularly aeration porosity and soil penetration resistance, which can vary among field zones. Vertical tillage has emerged as an alternative that can modify soil physical conditions while retaining the advantages of reduced soil disturbance. This study aimed to evaluate the effects of vertical tillage and its integration with seeding on soil aeration porosity, soil penetration resistance, spring wheat grain yield and tractor-related NOx concentrations during sowing. Four technologies were compared: minimum tillage (MT), vertical tillage (VT), vertical tillage combined with seeding (VTS), and no-tillage (NT). The results showed that VTS and NT generally maintained higher aeration porosity in the field interior during the later part of the experiment. Soil penetration resistance responses depended on field zone, sampling time, and soil depth, with the strongest treatment differences observed in the deeper headland layers. Spatial differences in soil physical properties demonstrated that the effects of tillage technologies varied between the field interior and headland zones. Yield assessments indicated that VTS achieved the highest spring wheat yield in the field interior, reaching 3.8 t ha−1 compared with 3.1 t ha−1 under MT, 3.2 t ha−1 under VT, and 3.4 t ha−1 under NT. During the sowing operation, mean NOx concentration followed the order MT > VT > VTS > NT. NT exhibited the lowest instantaneous concentration, while VTS showed a significantly lower concentration than MT; however, the difference between VTS and VT was not statistically significant. The lower mean NOx concentration observed under VTS compared with MT may provide an indirect indication of a lower engine-load response under the investigated sowing conditions. Overall, VTS provided favorable soil physical conditions by maintaining high aeration porosity in the investigated 10 cm layer and limiting soil penetration resistance, particularly in more compacted field zones, while also maintaining lower NOx concentrations than MT and VT during sowing.