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

Abstract

The soil microbiome of the Barents Sea coast of the Kola Peninsula is here characterized for the first time. The content of copies of ribosomal genes of archaea, bacteria, and fungi was determined by real-time PCR. Reserves and structure of biomass of soil microorganisms such as total biomass of fungi and prokaryotes, length and diameter of mycelium of fungi and actinomycetes, proportion of mycelium in biomass, number of spores and prokaryotic cells, proportion of small and large fungal propagules, and morphology of mycobiota spores were determined. The largest number of ribosomal gene copies was found for bacteria (from 6.47 × 109 to 3.02 × 1011 per g soil). The number of copies of ribosomal genes of fungi and archaea varied within 107–109 copies of genes/g soil. The biomass of microorganisms (prokaryotes and fungi in total) varied from 0.023 to 0.840 mg/g soil. The share of mycobiota in the microbial biomass ranged from 90% to 97%. The number of prokaryotes was not large and varied from 1.87 × 108 to 1.40 × 109 cells/g of soil, while the biomass of fungi was very significant and varied from 0.021 to 0.715 mg/g of soil. The length of actinomycete mycelium was small—from 0.77 to 88.18 m/g of soil, as was the length of fungal hyphae—an order of magnitude higher (up to 504.22 m/g of soil). The proportion of fungal mycelium, an active component of fungal biomass, varied from 25% to 89%. Most (from 65% to 100%) of mycobiota propagules were represented by specimens of small sizes, 2–3 microns. Thus, it is shown that, despite the extreme position on the mainland land of Fennoscandia, local soils had a significant number of microorganisms, on which the productivity of ecosystems largely depends.

Structure of Microbial Communities and Biological Activity in Tundra Soils of the Euro-Arctic Region (Rybachy Peninsula, Russia)

“…The length of fungal mycelium in the soils also varied greatly. It was comparable to that in the soils of the north of Novaya Zemlya [ 33 ], but less than on the coast of the Barents Sea [ 31 ]. Its lowest values were 14 and 29 m/g of soil in soils of cryogenic spot (RY10), and the highest, 413 m/g of soil, was found in Albic Podzol (RY09) ( Table S1 ).…”

“…In the soils of the Rybachy Peninsula, the fungal biomass changed from tens to hundreds mg/g soil ( Figure 3 A, Table S1 ). It was approximately equal to that on the coast of the Barents Sea [ 31 ], but less than in the background landscapes of the Kola Peninsula [ 32 , 33 ]. The minimum biomass (0.151 mg/g soil) was found in anthropogenically disturbed soil, and the maximum (0.463 mg/g soil) was found in Albic Podzol.…”

“…The length of fungal mycelium, as well as the biomass, was minimum in Entic Podzol (RY-08) and Folic Histosol (Technic) (RY-11); however, it was maximum in Albic Podzol (RY-09) and Folic Histosol (RY-14). The portion of thin (less than 3 µm in diameter) fungal mycelium in the soils was relatively large (up to 32%; in some samples, it reached 50–60%) compared to the percentage of that in the soils of Arctic cities located nearby, namely Apatity [ 34 ] and Murmansk [ 31 ]. A similar trend was found on the Barents Sea coast: mycelium averaged 42% of the total biomass [ 31 ].…”

“…The portion of thin (less than 3 µm in diameter) fungal mycelium in the soils was relatively large (up to 32%; in some samples, it reached 50–60%) compared to the percentage of that in the soils of Arctic cities located nearby, namely Apatity [ 34 ] and Murmansk [ 31 ]. A similar trend was found on the Barents Sea coast: mycelium averaged 42% of the total biomass [ 31 ]. The reason for this, perhaps, is the urban “heat island”, which is characteristic of cities beyond the Arctic Circle.…”

Urbanization Affects Soil Microbiome Profile Distribution in the Russian Arctic Region

“…For example, the length of the fungal mycelium in the studied soils was almost 1.5 times higher compared to Novaya Zemlya, a more northern location [ 69 ]. The proportion of thin (less than 3 μm in diameter) mycelium of the studied soils is relatively small compared to the urban soils of Apatity and settlements on the Barents Sea coast of the Kola Peninsula, where the proportion of fine mycelium exceeded 40% [ 65 , 70 ]. The number and biomass of prokaryotes in the studied soils of Murmansk were also 1.5–2 times higher than in other Arctic territories—Taimyr [ 71 ], Novaya Zemlya [ 69 ], and Franz Josef Land [ 72 , 73 ].…”