Microbiological activity of permafrost forest soils in Central Yakutia

Abstract

For the first time, a study of the microflora of permafrost forest soils of the Yakutsk Botanical Garden was implemented. It was found that in 2019 in the studied permafrost soils the number of microorganisms ranged from 103 to 106 CFU/g soil. Of all types of permafrost soils, humic calcareous soil (Rendzic Leptosols Eutric) appeared to be the most saturated with microorganisms, while solod soil (Stagnosols/Planosols) was the poorest. In the microflora of the studied permafrost soils, mycelial microorganisms predominated. Although this can not be said about solod, where ammonifying bacteria prevailed. Changes in the number of microorganisms mainly depended on soil temperature, humus and nitrogen content. Humidity and pH value in these soils turned out to be less significant in changing the composition of the microflora of these soils. Number of microorganisms and pH showed negative correlation. The study of the distribution of microorganisms along the profile of the studied forest soils showed that an increase in the number of bacteria and fungi was observed in the upper organogenic horizons, and their number decreased with depth.