Effect of different methods of cultivation and fertilization on the humidification mode within the periodically washing water regime of chornozem

Abstract

Goal. Based on the analysis of climatic parameters and reserves of productive moisture in the meter thickness of the soil, it is necessary to establish the influence of various methods of cultivation and fertilization on the deviation of the parameters of the moistening mode within the periodically washing water regime of typical chornozem in the agrocenosis of 5-field crop rotation for climate changes in the direction of warming in the central part of the Forest-Steppe of Ukraine. Methods. Field (collection of samples in the thickness of chornozem in different periods of research), laboratory (thermo-weight determination of productive moisture reserves for the period of research), mathematical, statistical, and comparative calculation (justification of the reliability of the obtained soil moisture sources and the development of statistical models of relationships). Results. The study was conducted (1977–2023) in the central part of the Left-Bank Forest-Steppe in the long-term (45 years) stationary experiment of the Drabiv experimental field of the Cherkasy State Agricultural Experimental Station of the NSC «Institute of Agriculture of the NAAS». It was established that the amount of atmospheric precipitation in the cold period of 2020–2023 compared to the period of 1977–1982 increased by 27 mm, and the reserves of productive moisture in the meter thickness of chornozem in April for plowing were, respectively, less by 50 and 35 mm, for no-till cultivation — by 38 and 43 mm, for surface cultivation — by 38 and 45 mm, than on control without fertilizers and on a fertilized background. At the same time, the reserves of productive moisture in April increased from 138–146 mm for plowing to 7 –16 mm for surface cultivation, providing optimally humidified conditions. The decrease in the reserves of productive moisture with an increase in precipitation in the cold season was associated with the absence of snow cover, physical freezing, and blowing of moisture in the winter. In July, with an increase in aridity for no-till and surface cultivation, the moisture reserves in the meter thickness were, respectively, 7–10 and 19–23 mm higher than for plowing, which corresponded to arid soil conditions, while for plowing, dry conditions prevailed. Conclusions. For 45 years of observation, the various-depth no-till cultivation was the most effective, as it provided high adaptability of grain crops to changes in weather-climatic conditions. It contributed to an increase in grain yields by 0.35–0.45 t/ha, or 20%, compared to the rate for plowing. For surface cultivation, crop yields were 0.04-0.11 t/ha, or 2.3–5.0%, higher than for plowing, but 0.31–0.34 t/ha, or 12–15%, lower than for no-till cultivation.