The impact of main tillage systems and fertilization for crops of a short crop rotation on agrochemical soil properties

Abstract

The problem statement. For the last two decades in Ukraine a fast decrease in chornozemic soil fertility, especially a decline of its agrochemical properties, has been noticed. One of the way of improvement its fertility is to develop and implement scientifically-based resource-saving and soil-protective system of tillage operations along with rational fertilization of field crops on the tilled soil. The aim of the research – with the help of a field experiment to define a rational system of main tillage and fertilization of typical chornozemic soil under a grain row five course rotation which provides 5,5 t/ha of dry matter from a tilled field under the expanded reproduction of agrochemical indices of soil fertility and appropriate energetic efficiency. Conclusions. Under disc and beardless tillage especially of fertilized areas a differentiation of tilled soil layer according to the agrochemical indices of its fertility is observed. A stabilization of humus and general nitrogen content as well as fertilizer elements in a tilled soil layer occurs under application of 8 t/ha of pus + N76P64K57. The efficiency of humification processes in soil is the lowest under disc tillage and the highest under beard-beardless and beard tillage in a crop rotation. Along with the increase of soil depth of its tilled layer, annual decrease of its general nitrogen supply on the untilled areas under beard and differential tillage falls down. However, under beardless and disc tillage it increases. An inverse relation is observed on the untilled areas. Under beard and beard-beardless tillage almost the same crop rotation productivity was obtained, while under beardless and disc tillage the productivity was significantly lower. For a field grain row five course crop rotation of Right Bank Forest-steppe of Ukraine a deep arable tillage is recommended only in one filed, and in the rest fields beardless and disc tillage with the application of 8 tones of pus per hectare of tilled field + N76P64K57 under a common reproduction and 12 t/ha of pus + N95P82K57 under expanded reproduction of typical chornozemic soil fertility is recommended. Key words: soil, tillage, crop rotation, fertilizers, fertility, rotation.