The purpose of the research was to identify the influence of mineral and organo-mineral fertilization systems during the main cultivation on changes in the biological activity of the arable layer of chernozem typical in the soybean agrocenosis of the five-field grain-row rotation of the Forest Steppe of Ukraine. The research was conducted during 2016–2020 on a typical deep low-humus chernozem of the Belotserkiv National Scientific Research Field. Three tillage systems were studied: differentiated, shelf-less and shallow, and three fertilization systems: without the use of fertilizers, organo-mineral and mineral.
It was established that the highest biological activity of typical chernozem in soybean crops in May was recorded during shelf-less tillage. The most pronounced differentiation of the arable layer was observed during shallow tillage. The difference in the weight loss of the linen cloth in the upper and lower parts of one layer of typical chernozem was 2,7% for differentiated, 7,7% - shelf-less, and 8,5% - shallow tillage.
The release of carbon dioxide from the soil in soybean agrocenosis in May is significantly higher than shelf-less tillage by 5,8%, shallow tillage without tillage by 2,7% compared to differentiated tillage.
Under the mineral fertilization system, the release of CO2 by the soil increased by 16,7–18,8% compared to the option without the use of fertilizers.