Effect of biopreparations on the decomposition of plant residues of crops in typical chernozem

Abstract

Aim. To identify the effect of biological preparations applied with or without nitrogen fertilizers for crop by-product, their incorporation into the soil on the decomposition of plant residues and composition of mobile humus substances in typical slightly eroded chernozem.Materials and Methods. The study was carried out in the field experimental station of Kursk FARC in the cycles of cereal and cereal-row crop rotations in variants with by-product treated with biopreparations; with applied biopreparations + nitrogen fertilizers; with applied nitrogen fertilizers and without biopreparations. To study decomposition the content of unhumified organic matter was determined in the topsoil by the monolith method after by-product incorporation into the soil and 3045 days after their decomposition. Simultaneously the composition of mobile humus substances in the soil was determined.Results. The decomposition of crop by-product and after harvesting and root residues mixed with it in the soil and treated with biopreparations or nitrogen mineral fertilizers was studied for the first time. The peculiarities of the effect of the factors studied on the degree of plant residue decomposition and the composition of mobile humus substances were shown.Conclusion. It was determined that treating the by-product of barley, buckwheat and sunflower with bioproducts, both with applied nitrogen fertilizers and without them, contributed to the increase in the degree of plant residue decomposition as compared with the control and nitrogen mineral fertilizer application. In the years which are favourable according to hydrothermal conditions the improved quality of mobile humus substances of the soil influenced by biopreparations are noted and under extreme conditions the tendency to the improvement of their quality is observed.