Role of Fungi and Bacteria in the Mineralization of Nitrogen Compounds in the Soil of the Southern Taiga Birch Forest in European Russia

Abstract

The contribution of fungi and bacteria to the process of net ammonification in the soddy–podzolic soil of the wood sorrel–bilberry birch forest of Yaroslavl oblast has been determined using inhibitory analysis. Representatives of the genera Penicillium Link (70–99%) and Trichoderma Pers. (6–20%) dominate in the mycobiota of saprotrophic fungi. Seasonal changes in the total number of fungi and the content of C_org and N_org in the soil correlate only in the eluvial horizon, with r = (–0.8) and (–0.7). In horizons A₀ and A₂, total fungal abundance is negatively correlated with nitrogen accumulation, with r = (–0.85) to (–0.89). It has been established that the litter is characterized by an equal participation of fungi and bacteria in this process. In the humus horizon, a slight excess of the participation of fungi over bacteria is noted. In the eluvial part of the profile, the contribution of bacteria is slightly higher than the contribution of fungi. The maximum air temperature is able to regulate the seasonal dynamics of the number of saprotrophic fungi in the soil.