Microbiological assessment of sod-medium podzolic soil using various elements of biologisation

Abstract

To assess the ability of soils to self-repair and self-rehabilitation, it is important to monitor the indicators of soil microbiological activity. In conditions of manure deficiency, the restoration of organic matter of soils is provided by using non-commercial share of the crop and growing green manure crops, which is especially important for zonal soils of Ukrainian Polissia. The purpose of the study was to estimate the number of various physiological groups of microorganisms in sod-medium podzolic soil under the influence of various fertiliser systems. Field, laboratory, and statistical methods were used in the study. Field method: an experiment was conducted in a field of the Chernihiv Institute of Agricultural Microbiology and Agroindustrial Production of the NAAS with an area of sown plots of 102 m2 on sod-medium podzolic light loamy soil with a humus content of 0.9-1.1% in 0-30 cm layer. The number of different groups of microorganisms that transform carbon and nitrogen compounds was determined in soil samples. Statistical methods – system analysis, mathematical and statistical analysis. Sowing of green manure such as lupine and oilseed radish had a positive effect on the number of ammonifiers (4.3-13.2 million CFU), which is 44-180% more than in the control. The mineral fertiliser system for potatoes also increased the number of ammonifiers by 15-50% compared to the option without fertilisers. The mineralisation-immobilisation coefficient was calculated as the ratio of the number of microorganisms that immobilise mineral forms of nitrogen to the number of organotrophs, and the pedotrophicity coefficient by the ratio of the number of microorganisms on soil agar to the number of microorganisms that grew on meat-peptone agar. It was established that the cultivation of green manure on sod-podzolic soil has a positive effect on the development of physiological groups of microorganisms and the microbiological processes tend to accumulate humus. The materials of the study are of practical value for agricultural producers who are engaged in growing potatoes on sod-podzolic soils in the possibility of replacing manure and mineral fertilisers in the fertiliser system of agricultural crops with green manure (lupine, oilseed radish)