The microbiological background of nitrogen-and carbon-bearing compounds' transformations in urban soils

Results of the long-term surveys of the microbial transformation of major biophilic elements in soils of urbanized areas are reported. The studies have demonstrated that the soil carbon and nitrogen cycles in urban ecosystems have both specific as well as common features shared with soils of undisturbed forest communities. The composition and structure of the microbial community were within the natural range of variations typical of soils in this climatic zone. Owing to the high informative value of the amino acid pool and basal respiration of the soils, they can be used as an environmental indicator. The range of variations of the microbial metabolic quotient can be recommended as an indicator of an early stage of disturbance of the soil system and changes in the quality of the natural environment. The data can be used as a background for the ecological urban soil monitoring in Eastern Fennoscandia.