BIOLOGICAL ACTIVITY OF SOIL DEPENDING ON FERTILIZER SYSTEMS

D. Fomin, V. Yamaltdinova, I. Teterlev, E. Mitrofanova, A. Kosolapova

Abstract: Soil microbial flora has an important role in the life of plants, providing them with nutrients and other factors. The research was aimed at studying the effect of the long-time fertilizer application on the number and composition of the microbial flora in the soil, involved in the synthesis and decomposition of organic matter. Studies were conducted in the Vth field rotation with a crop alternation: fallow land, winter rye, summer wheat with clover under sow, clover of the first year of use, clover of the second year of use, barley, potato and oat. We studied the effectiveness of various systems of fertilizers (organic, mineral, organic and mineral). Soil of experimental field was sod-podzolic. The use of arable land without fertilizers during five crop rotations (40 years) has led to a significant reduction of humus content, exchangeable potassium, and soil acidification. The use of mineral fertilizer systems also acidifies the soil. Joint application of manure and fertilizers led to an increase humus content in the soil. All the studied fertilizer systems increased the content of mobile phosphorus and exchangeable potassium and significantly changed its biological state of soil. Long-time use of fertilizer systems, compared with the control, helped to increase the total number of microorganisms, nitrogen-fixing and nitrifying bacteria, nitrification and cellulolytic activity of soil and carbon dioxide production. On the basis of conducted studies we have established the feasibility of long-time use of organic and mineral fertilizer system with saturation of arable land with manure of 10 t/ha and with an equivalent amount of mineral fertilizers for improvement of bacteria activity involved in nitrogen regime, soil respiration, processes of decomposition and the replenishment of organic matter that increase soil fertility.

Keywords: cellulolytic activity; fertilizer; nitrifying bacteria; nitrogen-fixing bacteria; soil respiration

Date published: 2017-09-04