INFLUENCE OF ROW SPACING AND MECHANICAL LOAD AREA ON HYDRO-PHYSICAL SOIL PROPERTIES

To determine the optimal agrotechnical measures for growing potato seed material. The following methods were used in the research: field – monitoring of hydro-physical soil properties in the experiment for growing potatoes, determining the effectiveness of combinations of row spacing, accounting for the yield; laboratory – determination of the hydrothermal coefficient (HTC), in accordance with generally accepted methods. Observations of changes in soil moisture depending on different row spacing after planting potatoes, at full germination, closing of potato tops in a row (flowering) and harvesting in 2020 show that the difference in soil moisture in the ridge (seed layer 5‑10 cm) after planting potatoes was the same and was in the range of 10.2‑10.4 mm. During the harvesting period in September, there was the least precipitation (22 mm) and the air temperature dropped to 15 0С. The reserve of productive moisture in the ridge in the tuber nest zone of 10‑15 cm was 10.1-10.9 mm. The hydrothermal coefficient during the growing season of potatoes was 1.3, and the highest average monthly HTC of 2.8 was in August. In 2022, before planting potatoes, the soil temperature at a 5‑10 cm depth was 9 0С. Subsequently, the air and soil temperature increased. During the harvesting period in September, there was the least precipitation (22 mm) and the air temperature dropped to 15 0С. The reserve of productive moisture in the ridge in the tuber nest zone of 10‑15 cm was 10.1‑10.9 mm. The hydrothermal coefficient during the growing season of potatoes was 1.3, and the highest average monthly HTC of 2.8 was in August. The research found that after planting potatoes, the lowest soil density (1.08‑1.16 g/cm3), regardless of row spacing, was in the ridge where the potato tubers were located. Thus, the determination of soil hardness in the rows, on the ridge slope and in the inter-row showed that with different row spacing, the impact of the running systems of agricultural units on the soil increases. During the harvesting period, the highest hardness of 27.4–32.4 kg/cm2 was established in the technological row spacing, a slightly lower value (15.2‑19.0 kg/cm2) was noted on the ridge slope and the lowest one (1.9‑2.6 kg/cm2) – in the centre of the ridge in the area where the tubers are located.