Influence of Tillage Systems on the Content of Organic Matter and Its Structural State

In a long-term stationary experiment on the basis of a 4-pole fruit-bearing crop rotation, the influence of processing methods with different levels of mechanical impact on the soil was studied: dump (plowing to a depth of 20–22 cm), combined (alternating plowing, plane-cutting processing (to a depth of 10–12 cm), without processing) and plane-cutting processing on the content of organic matter and the structural and aggregate composition of meadow-chernozem soil. It was found that a decrease in the intensity and depth of tillage with a combined and flat-cut system increased the humus content by 0.30 and 0.48% in a layer of 0–20 cm in comparison with dump treatment. The tillage system had a significant impact on the layer-by-layer distribution of labile organic matter in the form of mortmass. The largest stocks of mortmass in the arable layer were noted in the variant of the dump tillage system – 8.69 t/ha. On resource-saving backgrounds, a tendency to decrease the stocks of mortmass in the soil by 0.08–0.69 t/ha was revealed. The contribution of agronomically valuable structural units of 0.25–10 mm in size was 43.1–65.4 in layers, and the yield of large lumps and dust was 34.6–56.9% of the soil mass. The best structural condition of the soil is marked when using a dump treatment system. The presence of a close correlation between the stocks of mortmass in the soil layer of 0–20 cm and the content of structural-aggregate fractions with a size of 10–5 mm (r = 0.72 ± 0.11) and 5–3 mm (r = 0.68 ± 0.10) was established.