IMPACT OF BASIC TILLAGE SYSTEMS AND FERTILIZATION ON AGROCHEMICAL INDICES OF SOIL FERTILITY IN THE RIGHT BANK OF THE FOREST-STEPPE OF UKRAINE

The paper presents the results of stationary multifactor field experiment on study of the mutual impact of various systems of soil deep and surface tillage in combination with various levels of organic and mineral fertilizers application on crop rotation performance, as well as on a number of agrochemical indicators of black soil fertility. Researches were carried out as a stationary field experiment on the experimental field of Bila Tserkva National Agrarian University in 2013-2018. During the crop rotation in all the studied tillage methods, especially mouldboardless and disking tillage, the hydrolytic acidity of the arable layer increased with increase in fertilizer rates, and the amount of bases absorbed, saturation degree, level of exchangeable calcium and magnesium cations decreased, but in most cases these changes were not significant. Systematic mouldboardless and disking tillage enhance the topsoil heterogeneity in relation to agrochemical indicators of its fertility. Heterogeneity increases with increase in the level of applied fertilizers. With the mouldboard tillage during the crop rotation period at unfertilized areas, the largest part of humus loss in the arable layer is observed in the top, and the smallest in its bottom parts; the opposite pattern was observed on fertilized areas at the highest rate. With mouldboardless and disking tillage, directly opposite patterns were observed in comparison with mouldboard tillage. An annual application of 8 t/ha of manure N76P64K57 stabilizes the humus state of the arable soil layer when carrying out differentiated and disking tillage in crop rotation. Fertilization rate of 12 t/ha of manure + N95P82K75 for these tillage options a significant increase in humus and total nitrogen reserves is provided.