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Forest fires are among the most significant disturbances on a global scale. Affecting biodiversity and biogeochemical cycles, forest fires play an important role in atmospheric chemical processes and the global carbon cycle. Using the example of the pyrogenic landscapes of the Samara region, this article reviews changes in the accumulation regularity of heavy metal content and its migration within a soil profile during pyrogenic soil formation. In the case of surface forest fires, the studied postpyrogenic soils are characterized by increased cadmium, nickel and zinc content in the Opyr pyrogenic horizon. In contrast, the content of all analyzed heavy metals decreases compared to the control for crown forest fires, indicating active element emissions into the atmosphere.

Numerous published studies have shown that soil formation, including primary pedogenesis, is closely connected functionally, energetically and operationally with ecogenesis as a key biogenic exploration mechanism of the Earth’s surface by living organisms. The ontogenetic stage of soil evolution, especially in the initial phases, is determined by geogenic conditions and the intensity and trends of biogenic-accumulative processes in the developing ecosystem. Primary soils are considered critical in the rapid development of the initial ancient biosphere, supporting multiple environmental possibilities for ecosystems in that stage of their formation. Currently, similar models of correlated soil formation and ecogenesis are actualised when new substrates appear suitable for biogenic-abiogenic interactions, which occur in both natural and anthropogenic landscapes. Biotic factors during primary pedogenesis have accumulative and transformative effects on the edaphic component complex. At this stage, the initial pedon is a key functional stage in the evolution of terrestrial ecosystems (biogeocenosis). When restoration of natural ecosystems occurs during the independent growth of exposed substrates, the natural regeneration mechanisms normally occur. These processes are based on the biogenic development of the substrate through the accumulation and transformation of organic matter.

The Fergana valley is a region critically important for food safety in Central Asia. The human-altered soils in Fergana are considered a key component of the transboundary region between sub-boreal and sub-tropic climatic zones. As the results of the investigation of irrigated chloride-sulfate saline soils near the surface showed the deep petrocalcic and petrosalic horizons at various depths with extremely low water and air permeability. The chemical, pedogeochemical, and biogeochemical properties of soils, the content of macroelements, trace elements, lanthanides and radionuclides, and the general geochemical characteristics of desert zone soils were investigated and determined. The background contents of the mentioned elements were recognized. The irragic, salic, gleyic, and gypsic horizons in soils were identified by WRB 2015. They can be used as reference horizons for biogeochemical studies and soil management activities. The irragic, gleyic, carbonate-gypsum horizons, evaporation, oxygenic, and other geochemical barriers were studied and revealed. The processes of accumulation, migration, and differentiation of chemical elements in solum as well as in parent materials occur with the joint effects of exogenous, endopedogenic, and artificial factors. These fluxes of elements, in turn, are affected by the nature of soils and parent materials. In this process, unexplored elements form only scattering fluxes. During the vegetation season, as well as the leaching period, considering the various horizons features will help to save significant amounts of irrigation water.

The state of the microbial community is an essential factor determining the processes of soil restoration of disturbed soils. Quarrying and mining complexes are valuable sites for studying soil formation processes. Four different quarries (gypsum, sand–gravel mixture, sand, and clay) of the Republic of Bashkortostan were surveyed to determine the status of the microbial community of post-technogenic soils. Amplicon libraries of the 16s rDNA gene were analyzed. It was shown that the microbial communities of different soil horizons of quarries differ significantly. According to the results of the analysis, quarry communities demonstrate differences in the microbial composition of different horizons, while in some cases, the upper horizon is richer.

Soil microbiome plays a significant role in the development of the soil profile and the implementation of key soil biochemical processes. Observed Arctic warming creates significant environmental risks, since permafrost soils contain a huge amount of organic matter, which is in potential risk to be released in the form of greenhouse gases. This work is aimed to investigate the microbiomes in soils of mature tundra and anthropogenically affected areas of the Yamal region using a high-throughput sequencing approach. The taxonomic analysis of the soil microbiomes revealed 33 bacterial and archaeal phyla, among which the dominant were Proteobacteria, Acidobacteria, Actinobacteria, Bacteroides, Chloroflexi, Cyanobacteria, Firmicutes, Gematimonadetes, Patescibacteria, Plantomycetes, Thaumarchaeota, Verrucomicrobia, and WPS-2. The analysis of alpha and beta diversities revealed that undisturbed soil is completely different from anthropogenically affected ones in terms of microorganism biodiversity. Soils of the urban zone of Salekhard were found to be different with regard to the number of operational taxonomic units and beta diversity. Herein the microbiome in the upper and lower layers of soil developed under strong technogenic influence (M19) was unequal both in quality and in quantity. At the same time, soils developed in the recreational zone of Salekhard showed less differentiation profile of microbiome (former crop field and former vegetable garden soils). Microbial communities in the mature tundra soil showed less differentiated microbiome composition.

Precision agriculture requires a wide sampling procedure to determine the spatial variability of soil properties for adequate assessment of soil state and appropriate recommendations. Electrical geophysical methods (i.e. vertical electrical resistivity sounding) allow performing rapid measurement of soil electrical properties directly from the soil surface to any depth without any mechanical disturbance of soil cover. Soil electrical properties are linked with many soil properties and could improve the quality and spatial coverage of soil surveys. The results obtained in our study using vertical electrical resistivity sounding confirmed the hypothesis of a high correlation between electrical resistivity and such soil properties as carbon and nitrogen content and silt content. The highest correlation (r > 0.9) was found for electrical resistivity and carbon content. It was also confirmed that significant correlations between electrical resistivity and soil properties are found mainly when soil properties are highly ranged. Perspectives for the applied method lie at the relationship between electrical resistivity and soil properties, such as texture class, clay content, carbon content, and cation exchange capacity. The results obtained in this work could be useful for complex precision agriculture, creating maps of agricultural soils, adequate methods of plant growth, and other issues of precision and conventional agriculture.

The post-anthropogenic and soil cover transformations of former agricultural soils on the abandoned lands in the Russian Arctic territory are poorly investigated due to the active growth of the city complexes and increasing area occupied by agricultural lands. That is lead to an increase in the area of the arable lands surrounding the polar urbanized territories. Today, most of that land allocated for agricultural needs has been abandoned or affected by other types of land use. This study aimed to investigate the abandoned lands surrounding some of the settlements in the central part of the Yamal region. The soil diversity, morphology, and chemical and agrochemical properties were investigated with special reference to the specific transformations that occur to fallow lands under permafrost-affected cryogenic-ecosystem conditions. Analysis of data show that these soils are characterized by features relating to both, previous (and existing), anthropogenic impacts and natural processes such as cryogenic mass transfer. The degradation of the arable humus-enriched horizon was not as pronounced as it has been in more humid boreal environments over recent decades. The organic carbon content in topsoil depends on the land use and varied considerably among the soil types. The former arable topsoil horizon has been stable over time in terms of its morphological features and agrochemical state. Despite the high soil acidity levels, thenutrient content in the anthropogenically impacted soils was still high, even though being abandoned for 20 years.

Here we investigate the microbiomes of the soil samples from the Yamal Peninsula (the surroundings of Salekhard city, Russian Federation) using a high-throughput sequencing approach. The main goal was to investigate the impact of mining on soils within the following regeneration, both during the reclamation practice and natural self-growth. Several quarries were studied, engaged in sand, clay and chromatic ores mining. The taxonomic analysis of the soil microbiomes revealed 50 bacterial and archaeal phyla; among the dominant phyla were: Proteobacteria, Actinobacteria, Acidobacteria, Chroloflexi, Gemmatimonadetes, Verrucomicrobia, Planctomycetes, Bacteroidetes, AD3, and Nitrospirae. Compared to the typical tundra soil, which was chosen as a control, the disturbed soils had increased biodiversity and total counts for soil bacteria, archaea, and fungi, especially in the cryosolic horizon. The different mining strategies caused significantly different transformations of soil microbiomes, which was less pronounced for self-growth compared to reclaimed quarries. This isolation of the reclaimed quarry was mainly associated with the increase of the amount of acidobacteria (fam. Koribacteraceae and Acidobacteriaceae and order Ellin6513), some proteobacterial taxa (fam. Syntrophobacteraceae), and Chloroflexi (fam. Thermogemmatisporaceae). The study also revealed bacteria, which tend to be specific for marine tundra environments: gemmatimonadetes from the order N1423WL and Chloroflexi bacteria from the order Gitt-GS-136.

The aim of the work was to compare the taxonomic composition of the rumen procariotic community in young and adult individuals of Nenets breed reindeer (Rangifer tarandus ) from the central part of the Yamal region by using the NGS method (next generation sequencing) and compare the microbiome composition of reindeer with the microbiome of their initial vegetation food material. The obtained data showed that the dominant position in microbial communities, like that of other ruminants, was occupied by representatives of phylum Firmicutes and Bacteroidetes, whose total share between observed groups did not differ significantly. The composition of the microbiome of the rumen of the investigated group of animals was completely different from the microbiome structure of the initial vegetation cover. Digestion of vegetation by reindeers resulted in complex transformation in the initial plant microbiome and an increase of biological diversity which was expressed in operational taxonomic unit (OTU) numbers increasing and changes in indexes of alpha-diversity parameters. According to the results of alpha- and beta- diversity of the rumen microbial communities, the greatest uniqueness was revealed for the microbiomes of the adults in comparison with calves and young. The presence of changes in the biodiversity indexes of the rumen microbiota in the reindeer, examined by us, confirm the opinion of the researchers that the microbial community may also reflect the physiological state of the animals. It has also been demonstrated that the presence of the phylum Verrucomicrobia, and the genera Stenotrophomonas, Pseudomonas, etc., may be specific to Nenets breed reindeer and have a pattern with their presence on various plants and lichens that are part of the reindeer diet. This is partially confirmed by data on plants microbiome taxonomy.

Localization of agriculture with the aim of local food support has become a very urgent topic for Yamal region. The most fertile soils of this region are sandy textured anthropogenically affected soils. Microbiomes from disturbed soils of the Nadym region were studied using analysis of 16S rRNA metagenomic libraries. It was shown that plant cover is a driving force of microbiome composition. Forest soils covered with aeolian transfers from the quarry retaids a typical forest microbiome with the following dominant bacterial phyla: Proteobateria, Acidobacteria, Verrucomicrobia, Planctomycetes and Bacteroidetes. However, it contains significantly less Planctomycetes, which indicates greater aridity of the soil. The microbiomes of the overgrown quarries were strikingly differ from the soil microbiome and resemble those of arctic soils being dominated by Proteobacteria, Chloroflexi, Acidobacteria and Cyanobacteria. Absence of dense vegetation cover and availability of nutrients facilitated the formation of autotrophic microbial mats. The microbiome of the lower horizons of the quarry is characterised by Proteobacteria, Actinobacteria and Firmicutes. Presumably, most of the time these bacteria reside in a dormant state with short periods of activity due to nutrient uptake from the upper horizons.

Due to a significant increase in mining activity and subsequent ecosystem disturbances, it is becoming increasingly important to understand how degraded, unproductive quarries can be converted into new, self-sustaining communities that develop into natural environments. Former limestone quarry was investigated with aim to determine the best reclamation practice for surfaces of former lime rock quarries. Effects of spontaneous succession and forestry reclamation restoration approaches on vegetation and soil features were studied. The study was conducted in one of the largest limestone quarries of the Leningrad region, south taiga region. Species composition and vegetation cover were estimated for different plant communities within each ecotype of the quarry. Also soil characteristics were evaluated at each plot. We found that the main differences between plots were due to their position in the landscape; the most similar communities colonize similar ecotypes. On flat landforms, biodiversity is reduced under biological reclamation. At the sites under spontaneous succession, the level of biodiversity increases. In terms of biodiversity conservation and economic benefit, spontaneous succession is preferable to forestry reclamation for the restoration of carbonate substrates. After examining CO2 emissions from the quarry as a result of weathering of carbonates and soil respiration, as well as the level of CO2 sequestration from the atmosphere, we show that the establishment of certain landscape forms within former quarries can help to reduce atmospheric CO2.

Background concentrations of main trace elements and polycyclic aromatic hydrocarbons (PAHs) were investigated in pristine soils of the Beliy Island situated in the Kara Sea, Yamal autonomous region, North-West Siberia, Russia. Belyi Island is considered as reference landscpae for further investigation of soil polychemical contamination of the Yamal region. Three plots with different functional load (mature ecosystem, occasionally and permanently affected plots) were investigated with aim to evaluate the trend of long term polychemical effect on Stagnic Cryosols – benchmark soil type of the Yamal region. Accumulation of trace elements was not fixed in all soils investigated due to absence of direct sources of heavy metals on the territory of the Beliy Island. At the same time, there were essential alterations of PAHs fractional composition and content due to pronounced accumulation of the petroleum products combustion in the vicinity of the permanent meteorological station and former seasonal field base. The most intensive and statistically significant accumulation was noted for phenanthrene, anthracene, benzo[k]fluoranthene and benzo[a]pyrene. This indicates accumulation of the PAHs in soils, affected by the anthropogenic activity on the meteorological station. The most pronounced differences were revealed for the superficial layer of 0–5 cm. Deeper horizons of soil did not show accumulation of contaminants. Data obtained can be used for organization of further monitoring of contamination of soils and landscapes in Yamal as developing and industrial region.

Soils of Russian European North were investigated in terms of stability and quality of organic matter as well as in terms of soils organic matter elemental composi­tion. Therefore, soil humic acids (HAs), extracted from soils of different natural zones of Russian North-East were studied to characterize the degree of soil organic matter stabilization along a zonal gradient. HAs were extracted from soil of different zonal environments of the Komi Republic: south, middle and north taiga as well as south tundra. Data on elemental composition of humic acids and fulvic acids (FAs) extracted from different soil types were obtained to assess humus formation mechanisms in the soils of taiga and tundra of the European North-East of Russia. The specificity of HAs elemental composition are discussed in relation to environmental conditions. The higher moisture degree of taiga soils results in the higher H/C ratio in humic substances. This reflects the reduced microbiologic activity in Albeluvisols sods and subsequent conser­vation of carbohydrate and amino acid fragments in HAs. HAs of tundra soils, shows the H/C values decreasing within the depth of the soils, which reflects increasing of aromatic compounds in HA structure of mineral soil horizons. FAs were more oxidized and contains less carbon while compared with the HAs. Humic acids, extracted from soil of different polar and boreal environments differ in terms of elemental composition winch reflects the climatic and hydrological regimes of humification.

Determination of geochemical and microbiological properties of the cryoconite, related types of sediments and periglacial soils is essential to investigate impact of glaciers on terrains development at the Central Caucasus region. The studied sediments were sampled at the Garabashi and Skhelda glaciers as well as in vertical sections of local soils at the Baksan gorge. Sampled materials were investigated in terms of physicochemical parameters and nutritional state. The trace elements concentrations (Cu, Pb, Zn, Ni, Cd) were also evaluated in samples selected. The data obtained shows much higher content of organic carbon in soils (up to 7.82%) in comparison with cryoconite (max. 1.63%) due to the effect of superficial vegetation cover, however, rates of microbial activity were similar between some samples of sediments and soils. The analysis of the particle size distribution shows a similarity of the studied materials: in almost all samples, there is a dominance of the sand fraction. Cryoconite sediments on both of the above-mentioned glaciers are found as enriched with phosphorus, essential values of potassium (298 mg/kg in K2O units) and ammonium nitrogen (N-NH4 - max. 247 mg*kg) are identified at Garabashi glacier which could be a result of long-distant transfer and anthropogenic activity. The highest content among trace elements was identified for Zn (62 mg*kg for cryoconite and 60.5 mg*kg for soils), the most contaminated materials were sediments from Garabashi glacier and Entisols, up to moderate level, which is mostly associated with anthropogenic activity. Thus, development of tourism in the Central Caucasus, which is mostly associated with construction and transport, affects the pollution status of supraglacial sediments and periglacial soils as well as their agrochemical and microbiological features.

Active layer thickness and the depth of the permafrost are the basic features of the soil cover of the Arctic region. Urban ecosystems are characterized by disjunctive character of soil cover. Identification of separate soil bodies within the urban ecosystems, their spatial limitation and vertical stratification should be performed for adequate ecological assessment of urban territories. Methods of field electrophysics, which do not lead to any mechanical disturbances of soil cover, should be preferably used for both urban and natural environments. Studied soil profiles revealed significant differences in profile distribution of electrical resistivity values and active layer depths. Predominance of sand fraction in soil of Salekhard site (Spodic Cryosol) determines higher rates of thawing process compared to soil from natural site (Aquiturbic Cryosol), where clay is predominant fraction. Both soil profiles and their electrical resistivity curves are significantly affected by natural cryoturbation processes. However, vertical profile of electrical resistivity value in urban soil is more complicated and has a number of fluctuations due to higher rates of ground mixing, mechanical pressure and high amount of artefacts.

In recent decades rates of anthropogenic forcing on natural and urban ecosystems in the Arctic are increasingly growing. This tendency requires the development of more detailed environmental monitoring methods. In this context, study of background trace elements contents should be an urgent task. The purpose of authors study was an assessment of trace elements content in soils of urban environments in Yamal region and Murmansk. Twelve sites in Yamal region and four sites in Murmansk in different functional zones were studied during the investigation. Samples were taken from a depth of 0-5 cm and 5-20 cm. The highest contents for Cu, Zn, Ni were found in soil samples from Kharp, which was caused by existing chrome-processing factory. Soil samples from Aksarka and Labytnangi were characterized by the highest median values for Pb. Soil samples from Kharsaim and Kharp key plots were characterized by the highest median values for Zn. This could be explained by geological origin and high regional background concentration element for this trace element. Soil samples collected in Murmansk were characterized by highest medians in Pb, Ni and Mn in topsoil horizons, Mn and Zn in lower horizons. Evaluation of Saet´s index showed the predominance of non-hazardous Zc in most of the soil samples. Predicted climate change and consequent degradation of permafrost in soils could have the behavior of trace elements. Rates of accumulation, transformation, translocation, leaching and transportation of trace elements and other pollutants within the permafrost-affected landscapes could be affected and changed significantly.