Microbiological diagnostics of the status of pyrogenically changed pine forests in the Lower Angara River basin

The structure and functions of the microbial complexes in the soils after surface fires of different intensity were studied. The fires of high and medium intensity were found to lead to a significant decrease in the number and functional activity of microorganisms participating in the nitrogen-carbon cycle. The degree of changes in the postfire status of the soil microbocenoses was revealed to be related to the joint action of pyrogenesis and the hydrothermal conditions at the moment of the fire rather than to the fire intensity. The favorable combination of the elevated soil moisture and soil heating stimulates the microbiological processes of organic matter mineralization, thus, improving the forest-growing conditions for the pine forests. The microbial biomass, basal respiration, and the microbial metabolic coefficient are shown to adequately reflect the postfire status of the microbial complexes.