Correlation links of physiological groups of microorganisms with fertility indicators of degraded chernozem for different fertilizer systems

Abstract

Goal. To develop a comparative correlation model of the interconnections of ecological-trophic groups of soil microorganisms with agrophysical, physicochemical indicators, humus condition, the productivity of the degraded chernozem and to determine the energy efficiency of the use of intensive, low-intensive, and organic fertilizer systems using the by-products of crops as organic fertilizers in the 5-field grain-spray crop rotation for the conditions of the Central Right-Bank Forest-Steppe. Methods. Field and laboratory experiments, statistically analytical method. Results. Taking into account that use of the intensive fertilization system causes an overdrying of a layer of degraded chernozem 0-20 cm, and the use of an organic system increases the level of moisture, it can be argued that the best conditions for preserving the organic substance of humus are created for an organic fertilizer system. For organic and low-cost fertilization systems, the saturation of the soil complex Ca2+ is carried out by reducing the chemical load on chernozem. That leads to a decrease in the level of metabolic acidity and amplification of biogenicity due to the growth of the number and activity of ammonifying, amylolytic, pedotrophenic, oligotrophic microorganisms and the decrease in the activity of the humus-extraction groups of microorganisms, which provides reproduction of humus in the agrocnosis of short-crop rotation. Conclusions. For an intensive fertilizer system, the density of the structure increases when the drainage of soil conditions increases, which enhances the process of mineralization of humus due to the growth of the activity of humus extraction microorganisms. For organic and low-intensive fertilizer systems, there is a loosening of a 0-20 cm layer of chernozem, which stimulates the increase in the activity of ammonifying and pedotrophemical groups of microorganisms. To a lesser extent, it influences the biogenicity and activity of amylolytic and oligotrophic groups of microorganisms.