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A biotechnology based on sorption-biological treatment for the restoration of the Arctic coastal areas after oil spills was proposed. A hydrocarbon-oxidizing microbial preparation based on microfungi (Penicillium janthinellum, Penicillium simplicissimum) and bacteria (Pseudomonas fluorescens, Pseudomonas putida) was created. Granular activated carbon, thermoactivated vermiculite, and peat were used as sorbents. The sorbents are concentration centers for microorganisms, prevent the spread of hydrocarbons, and improve the condition of the polluted substrate by optimizing the water-air regime. After treatment, sorbents are not removed from the soil. As a result of laboratory studies at +10°C, the hydrocarbon content in the polluted coastal sand was reduced by 44-60%, and in the coastal soil by 25-68% after three months. This technology can be used at the final stage of coastal areas cleaning, as well as the only method of cleaning in highly sensitive areas. The use of aboriginal hydrocarbon-oxidizing microorganisms, typical of most coastal substrates of the Euro-Arctic region, excludes changes in the structure of the microbial community in these areas. The adaptation of these microorganisms to extreme climatic conditions allows biological treatment to be carried out with high efficiency in the Subarctic and Arctic.

Intensive human activity in the Arctic region leads to hydrocarbon pollution of reservoirs and soils. Isolation of bacteria capable of growing at low temperatures and degrading oil and petroleum products is of scientific and practical value. The aim of this work was to study the physiology and growth in oil at temperatures below 0 °C of four strains of bacteria of the genera Pseudomonas, Rhodococcus, Arthrobacter, and Sphingomonas—previously isolated from diesel-contaminated soils of the Franz Josef Land archipelago—as well as genomic analysis of the Sphingomonas sp. AR_OL41 strain. The studied strains grew on hydrocarbons at temperatures from −1.5 °C to 35 °C in the presence of 0–8% NaCl (w/v). Growth at a negative temperature was accompanied by visual changes in the size of cells as well as a narrowing of the spectrum of utilized n-alkanes. The studied strains were psychrotolerant, degraded natural biopolymers (xylan, chitin) and n-alkanes of petroleum, and converted phosphates into a soluble form. The ability to degrade n-alkanes is rare in members of the genus Sphingomonas. To understand how the Sphingomonas sp. AR_OL41 strain has adapted to a cold, diesel-contaminated environment, its genome was sequenced and analyzed. The Illumina HiSeq 2500 platform was used for AR_OL41 genome strain sequencing. The genome analysis of the AR_OL41 strain showed the presence of genes encoding enzymes of n-alkane oxidation, pyruvate metabolism, desaturation of membrane lipids, and the formation of exopolysaccharides, confirming the adaptation of the strain to hydrocarbon pollution and low habitat temperature. Average nucleotide identity and digital DNA–DNA hybridization values for genomes of the AR_OL41 strain with that of the phylogenetically relative Sphingomonas alpine DSM 22537T strain were 81.9% and 20.9%, respectively, which allows the AR_OL41 strain to be assigned to a new species of the genus Sphingomonas. Phenomenological observations and genomic analysis indicate the possible participation of the studied strains in the self-purification of Arctic soils from hydrocarbons and their potential for biotechnological application in bioremediation of low-temperature environments. [ABSTRACT FROM AUTHOR]

A comprehensive study of the quantitative and qualitative parameters of soil microfungi, bacteria and algae communities in the Apatity city, located in the subarctic zone of Russia, was carried out for the first time. Urban soil samples were taken from various landuse zones (residential, recreational) and compared to arable and forest soils. In the residential zone, a decrease in the number of microfungi in the topsoil horizon to 1.1 thous. CFU/g compared to 22.7 thous. CFU/g in forest soil was revealed. In the residential zone, an increase was found in the number of saprotrophic bacteria to 7.8 million cells g-1 and oligotrophic to 10.9 million cells g-1 compared to 2.6 million cells g-1 and 1.8 million cells g-1 respectively in forest soils. In the recreational zone, the number of soil micro-organisms was similar to that in the forest. A decrease in the species diversity of microfungi in the soil of the residential zone and an increase in the diversity of soil algae were revealed. Among the dominant species of fungi in urban soils, atypical species, including pathogenic ones for humans (Penicillium dierckxii, Stachybotris echinatus, Fusarium sp.), were found. In the algal community, diatoms, yellow-green algae, and cyanobacteria appeared in urban soils in comparison with forest soil. As a result of changes in the quantitative and qualitative indicators of soil microbial communities, a decrease in the enzymatic activity of soils has been noted. This may indicate a weakening of the ecosystem functions of urban soils and an increase in the degree of toxicity for living organisms and humans. [ABSTRACT FROM AUTHOR]

This report presents the results of applying various bioremediation methods of soils contaminated with oil products in the northern regions on the example of the Murmansk region. We investigated the effectiveness of plants, fertilizers, sorbents and microorganisms to purify oil contaminated soil in the field model experiment and under condition of real long-term contamination. The upper limit of potential self-purification of mineral soils in the region is determined: 15 g/kg for light oil, 5 g/kg for dark oil with a contamination depth of no more than 10 cm. Mineral and organic fertilizers enhanced the activity of native hydrocarbon-oxidizing microorganisms and the efficiency of purification of contaminated soil has increased by 20-50%.A group of plants with high resistance to oil pollution in the Arctic was selected for the phytoremediation of soils: reed canary grass (Phalaroides arundinacea), meadow fescue (Festuca pratensis), timothy grass (Phleum pratense), and blue-lyme grass (Leymus arenarius). The possibility of using rolled lawns (phytomats) on the basis of a soil-substitute vermiculite substrate for the bioremediation of oil-contaminated soils was studied. At the initial stages of growth, when plants are most vulnerable to environmental toxicity, the development of the root system occurs in the substrate. Subsequently, the plants roots penetrate deeper, and the phytomate is fixed on the surface of the contaminated soil. Microbial associations based on native microbes accelerate the decomposition of oil products in soil by 10–20% in the Albic Podzols of the Kola Peninsula. The fungi Penicillium canescens st. 1, P. commune, P. ochrochloron, P. restrictum, and P. simplicissimum st. 1 isolated from contaminated soils were selected for this study as the active destructors of oil hydrocarbons. The efficiency of microbial associations (bacteria Pseudomonas fluorescens, P. putida, P. baetica, and Microbacterium paraoxydans and fungi Penicillium commune, P. canescens st. 1, and P. simplicissimum st. 1) for soil purification from oil products was evaluated. The bacterial–fungi association was more effective; the content of oil product has reduced by 82% over 120 days. Five strains of hydrocarbon oxidizing microscopic fungi (Tolypocladiun inflatum st. 49, T. inflatum st. 30, Meyerozyma guilliermondii, st. KA17, st. KA22-4) and two strains of hydrocarbon oxidizing bacteria (st. 7, st. 3) were selected to purify coastal zones of the Barents Sea. The strains showed a high ability to destroy oil products by 60-78% in a laboratory experiment. [ABSTRACT FROM AUTHOR]

Intensive human activity in the Arctic region leads to hydrocarbon pollution of reservoirs and soils. Isolation of bacteria capable of growing at low temperatures and degrading oil and petroleum products is of scientific and practical value. The aim of this work was to study the physiology and growth in oil at temperatures below 0 °C of four strains of bacteria of the genera Pseudomonas , Rhodococcus , Arthrobacter , and Sphingomonas -previously isolated from diesel-contaminated soils of the Franz Josef Land archipelago-as well as genomic analysis of the Sphingomonas sp. AR_OL41 strain. The studied strains grew on hydrocarbons at temperatures from -1.5 °C to 35 °C in the presence of 0-8% NaCl ( w / v ). Growth at a negative temperature was accompanied by visual changes in the size of cells as well as a narrowing of the spectrum of utilized n -alkanes. The studied strains were psychrotolerant, degraded natural biopolymers (xylan, chitin) and n -alkanes of petroleum, and converted phosphates into a soluble form. The ability to degrade n -alkanes is rare in members of the genus Sphingomonas . To understand how the Sphingomonas sp. AR_OL41 strain has adapted to a cold, diesel-contaminated environment, its genome was sequenced and analyzed. The Illumina HiSeq 2500 platform was used for AR_OL41 genome strain sequencing. The genome analysis of the AR_OL41 strain showed the presence of genes encoding enzymes of n -alkane oxidation, pyruvate metabolism, desaturation of membrane lipids, and the formation of exopolysaccharides, confirming the adaptation of the strain to hydrocarbon pollution and low habitat temperature. Average nucleotide identity and digital DNA-DNA hybridization values for genomes of the AR_OL41 strain with that of the phylogenetically relative Sphingomonas alpine DSM 22537 T strain were 81.9% and 20.9%, respectively, which allows the AR_OL41 strain to be assigned to a new species of the genus Sphingomonas . Phenomenological observations and genomic analysis indicate the possible participation of the studied strains in the self-purification of Arctic soils from hydrocarbons and their potential for biotechnological application in bioremediation of low-temperature environments.