Soil Mycobiota of the Apatity City (Murmansk Region)

— The soil mycobiota of the Apatity city was first characterized. Significant differences in the quantitative and qualitative parameters of urban soil microfungal complexes in the Arctic zone in comparison with zonal soils were revealed. It was shown that the fungal biomass in the soil of the recreational zones of Someriumbric Leptic Entic Podzol (Arenic) was 0.18–0.20 mg/g; in the background forest soil Leptic Albic Podzol (Arenic, Folic), 0.31 mg/g. The lowest values (0.04–0.08 mg/g) was typical of zones with no vegetation and a densely compacted surface (playground – Leptic Entic Podzol (Arenic, Technic), unpaved pedestrian walkway – Someriubric Leptic Albic Podzol (Arenic). In the recreational and forest zones, soil fungi were mainly in the mycelium form (66–70% of the total biomass), while in the residential and agricultural zones soils in the form of spores. Spores were mainly represented by small forms up to 3 µm. The number of large spores was insignificant, but they were mainly detected in the soil of the residential zone. The number of ITS rRNA gene copies of fungi in soils of different functional zones varied from 4.0 × 10 9 to 1.14 × 10 10 copies/g of soil, with the highest values in the natural forest Podzol and Podzol of the unpaved pedestrian walkway. The number of microfungi CFU in topsoil ranged from 1 × 10 3 to 9 × 10 4 CFU/g of soil, reaching maximum values in the Someriumbric Leptic Entic Podzol (Arenic, Technic) soil of the recreational zone. The features of the cultivable microfungi distribution on the soil profile in different functional zones were revealed: in the residential zone Podzol, the maximum accumulation of fungi was noted in the subsoil, while in the recreational, agricultural and forest zones, their maximum number was noted in the topsoil. However, the first two differed from the background one in the absence of a second maximum accumulation of microfungi in the subsoil illuvial spodic horizon (Bs). In general, urban soils were characterized by a low species diversity of saccharolytic microfungi and a specific structure significantly different from the background soils. The genus Penicillium was characterized by maximum species diversity. Trichocladium griseum and Penicillium dierckxii dominated in the microfungi communities in the residential zone soil; P. melinii - in the recreational zone and in playground soils; microfungi of the genus Fusarium - in the agricultural zone soil Umbric Entic Podzol (Arenic); and P. decumbens - in the background forest soil.