Динаміка гетерогенності агрофізичної якості чорнозему звичайного у межах сільськогосподарського поля

Abstract

The article presents data on monitoring the physical characteristics of the soil in a field under corn (after sunflower) in a grain-row crop rotation with minimal tillage technology. Soil – Calcic Chernozem, light-medium clayey, weakly xeromorphic on loess in the Donetsk region in the Steppe climate zone of southeastern Ukraine. The research carried out in a stationary field experiment to study the effectiveness of abandoning plowing under the soil and climatic conditions of the region. During the growing season of corn for grain, the physical characteristics of the soil were monitored – bulk density, penetration resistance, and moisture content; before sowing the crop, the structural condition was determined. Measurements carried out in three locations – zones of the field, which differ on the intensity of compaction by agricultural machinery. All physical characteristics were investigated in separate layers (0–10, 10–20, and 20–30 cm) within the arable layer; reserves of productive moisture — in the entire soil profile. Meteorological data were obtained by own observations at a weather station in the nearby village of Sukha Balka. According to the results of the correlation and dispersion analysis of ANOVA, the presence and nature of the relationship between stability characteristics, rheological features and the water regime of the soil with its structural composition within the arable layer recorded before sowing revealed. Uneven distribution within the field of intensity of mechanical pressure on the soil forms differences in the structural composition and physical characteristics of the soil. For example, according to the state of moisture in a layer of 0-10 cm, the soil in different parts of the field is in a state of overwetting, overdried or optimal. The bulk density of the upper soil layer is related not only to its own structural characteristics, but also to the composition of aggregates in the layer located below. High penetration resistance, high aggregate content of 5-3 mm and low aggregate content of 2-1 mm in the upper layers can cause deep soil deformation under machine pressure. The dynamicity of the bulk density of the upper soil layer, its low content of aggregates of 5–3 mm and high content of 2–1 mm provides protection against compaction of the soil layers located below.