Urban Soils Mycobiota of the Subarctic (Apatity, Murmansk region, Russia)

Abstract

<p>The soils mycobiota of Apatity was first characterized. Significant differences in quantitative and qualitative parameters of urban soils fungal complexes of the Subarctic zone in comparison with zonal soils were revealed. It was shown that the biomass of fungi in the soil of the residential area of Umbric Leptic Entic Podzol (Arenic, Neocambic) is 0.18 – 0.20 mg/g, in the background forest soil Folic Leptic Albic Podzol (Arenic) – 0.31 mg/g. The smallest values (0.04 – 0.08 mg / g) are typical for areas with no vegetation and a densely compacted surface (playground - Leptic Entic Podzol (Arenic, Neocambic, Technic), unpaved pedestrian walkway – Umbric Leptic Entic Podzol (Arenic, Neocambic).</p><p>In the soils of recreational and forest areas, fungi were mainly in the form of mycelium (66-70% of the total biomass), while in the soils of residential and agricultural areas in the form of spores. Spores are mainly represented by small forms up to 3 microns. The amount of large spores is insignificant, but they were mainly detected in the soil of the residential area.</p><p>The number of copies of ITS rRNA genes of fungi in soils of different functional zones varies from 4.0×10<sup>9</sup> to 1.14×10<sup>10 </sup>copies/g of soil, with the highest values in the natural Podzol of the forest zone and Podzol of the unpaved pedestrian walkway.</p><p>The number of micromycetes CFU in the upper soil horizon ranges from 1×10<sup>3</sup> to 9×10<sup>4</sup> CFU/g of soil, reaching maximum values in the soil of the Umbric Leptic Entic Podzol recreation zone (Arenic, Neocambic, Technic). The features of cultivated forms of micromycetes distribution on the soil profile in different functional zones were revealed: in the Podzol of the residential area, the maximum accumulation of fungi was noted in the lower horizons, while in the soil of the recreational, agricultural and forest areas, their maximum number was noted in the top horizon. However, the first two differed from the background one in the absence of a second maximum accumulation of micromycetes in the illuvial Bs horizon.</p><p>In general, urban soils were characterized by a low species diversity of micromycetes complexes and a specific structure significantly different from the background soils. The genus Penicillium is characterized by maximum species diversity. Trichocladium griseum and Penicillium dierckxii dominate in the communities of microscopic fungi in the soil of the residential zone, P. melinii in the soil of the recreational areas and in the playground, in the soil of agricultural area Plaggic Entic Podzol (Arenic) - micromycetes of the genus Fusarium, and in the background forest soil - P. decumbens.</p>

Qualitative and Quantitative Characteristics of Soil Microbiome of Barents Sea Coast, Kola Peninsula

“…The number of copies of the 16S rRNA ribosomal genes of archaea in coastal soils is, on average, 2–3 orders of magnitude lower than in forest and urban soils of the northern taiga zone of the Kola Peninsula and is comparable with that in the forest–tundra zone [ 19 ]. We believe that the coastal areas of the Kola Peninsula are less favorable for archaea than the urban environment in the subarctic climate due to the “heat island” effect [ 20 , 21 ] and large reserves of organic matter [ 22 , 23 ] in the urban soils. It should be noted that, despite the lack of nutrients in sandy soil, the number of copies of archaean genes does not differ significantly from that in the soil, in contrast with other groups of microorganisms—bacteria and fungi.…”

“…Fungal biomass. In the studied substrates of the Barents Sea coast, biomass of mycobiota was less than in background landscapes of the Kola Peninsula [ 5 , 7 ], but it was 1.5–2 times higher than in soils of the city of Apatity, which is located farther south in the Murmansk region [ 21 ]. Apparently, this may be due to such limiting factors as heavy metal pollution by powerful enterprises in the cities of the Kola Peninsula [ 28 , 29 ].…”

“…We assume that such a difference in the length of the fungal mycelium can primarily be explained by the severity of the climatic conditions. The proportion of thin (less than 3 μm in diameter) mycelium in the studied soils was relatively high (up to 42%) compared with the percentage of that in urban soils of Apatity and Murmansk [ 21 ]. Perhaps this may be due to the “heat island” effect characteristic of cities beyond the Arctic Circle [ 20 , 21 ].…”

“…The proportion of thin (less than 3 μm in diameter) mycelium in the studied soils was relatively high (up to 42%) compared with the percentage of that in urban soils of Apatity and Murmansk [ 21 ]. Perhaps this may be due to the “heat island” effect characteristic of cities beyond the Arctic Circle [ 20 , 21 ]. Extra warmth from a city can stimulate the growth of soil fungi.…”

“…Extra warmth from a city can stimulate the growth of soil fungi. Basidiomycete buckle mycelium of fungi was found rarely (about 5% of all hyphae), and only in surface organogenic layers, which was 4–8 times lower compared with the proportion of such mycelium in urban soils of the Kola Peninsula [ 21 ]. The fact may indirectly indicate a low number of mycorrhizal symbioses [ 32 ].…”