Agrophysical indicators of soil for growing winter barley in the Transcarpathia of Ukraine

The study presents the values, tasks, and results of various methods of basic tillage for different predecessors on its agrophysical properties for growing winter barley in the Transcarpathia of Ukraine. The soil of the experimental field is sod-podzolic gumbo, which contains an average of 2.6% humus in the humus horizon. With depth, the amount of humus decreases gradually and at a depth of 100-130 cm it reaches 1.0-1.7%. The soil is typical for the area where the study was conducted and is moderately provided with mobile forms of phosphorus, potassium, and nitrogen. A qualitative assessment of the examined soils showed that the soil requires constant use of organic and mineral fertilisers, liming, and the introduction of crop rotations. The soil density is an important indicator of the physical properties of the soil, which affects not only the soil regimes but also the quality of its cultivation, which ultimately affects the yield of the crop and its quality. For the period of sowing winter barley, the most favourable indicators of the volume mass of 0-10 cm of the soil layer were provided by all systems of basic cultivation. The average soil density for the main cultivation options ranged between 1.09-1.17 g/cm3, at HIP0.5 = 0.01 g/cm3. At a depth of 10-20 cm, the average volume mass of soil during ploughing was 1.14 g/cm3, for chiselling, it was without substantial differences – 1.15 g/cm3. Conducting shallow (12-14 cm) and surface (6-8 cm) cultivation was accompanied by an increase in volume mass indicators to 1.16 and 1.19 g/cm3, respectively. In the soil layer of 20-30 cm, it was similar: with shallow chisel cultivation, the average density was at the level of 1.24 g/cm3, and on the surface – 1.25 g/cm3. The precursors did not substantially affect the change in the density of the tillage layer of the soil. However, after corn for grain and sunflower, there is a tendency to increase the volume mass of the soil after chisel shallow and surface cultivation, especially in the lower layers of the soil. This soil density was at the level of 1.24-1.26 g/cm3, which is within the optimal limit. The soil, loosened by mechanical cultivation, self-compacts during the growing season to an equilibrium density under the influence of its own mass, moisture, and drying. Therefore, during the period of earing and harvesting of winter barley, the soil gradually compacted to natural values. In a 0-10 cm layer of soil, the volume mass varied in the range of 1.20-1.27 g/cm3, in the soil layer of 10-20 cm – from 1.25 to 1.30 g/cm3, and in 20-30 cm – from 1.34 to 1.37 g/cm3. For the effective activity of microorganisms, the growth and development of the root system of plants, and the accumulation of moisture in the soil, density (porosity) is important. It was identified that long-term use of the deep and chisel tillage did not reduce the overall porosity below 50% of the structure of the cultivated layer, which ensured the high productivity of cultivated plants. For the surface and shallow chisel tillage, the total porosity in the lower layers was up to 50% of the structure of the cultivation layer, and in some cases less than 47%. This structure of the cultivation layer negatively affected the water and air regimes of the soil, the growth and development of the root system, and, ultimately, the yield of winter barley. The highest yield of winter barley was obtained after buckwheat, winter rapeseed and soybeans (6.0-6.3 t/ha) during chisel tillage to the depth of 20-22 cm. After corn for grain and sunflower, the yield was 5.1-5.7 t/ha