Table of contents

On behalf of the Organising Committee and the Editors of this volume, we are delighted to present the Proceedings of IV All-Russian Conference with International Participation "Diversity of Soils and Biota of Northern and Central Asia" "DSBNCA-2021"), which was held in Ulan-Ude, Russia, June 15-18, 2021.

List of Chairman, Co-Chairmen, Scientific Committee, Scientific Secretariat and Organising Committee are available in this pdf.

All papers published in this volume of IOP Conference Series: Earth and Environmental Science have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

• Type of peer review: Single-blind

• Conference submission management system: submissions were received and handled via Conference e-mail: igeb.biodiversity21@gmail.com

• Number of submissions received: 65

• Number of submissions sent for review: 63

• Number of submissions accepted: 42

• Acceptance Rate (Number of Submissions Accepted / Number of Submissions Received X 100): 64.6%

• Average number of reviews per paper: 2

• Total number of reviewers involved: 19

• Any additional info on review process: Each paper took 2 weeks for revisions after review; 2 rounds of the review process were applied.

Contact person for queries:

Name : Oleg A. Anenkhonov, Dr. Sci. (Biol.)

Affiliation: Institute of General and Experimental Biology SB RAS

Email : anen@yandex.ru

The Baikal Rift Zone hosts many hot springs with a wide range of temperature and physical-chemical conditions, which may harbour different niches for the distribution of microbial communities. We investigated microbial community composition and their functional activity in two alkaline hot springs with a temperature range of 34.4 to 73.6°C. Comparative analysis of the composition of the dominant taxa showed significant differences depending on the collection sites. In the community of high-temperature zones with a water temperature of 55-64°C, a high proportion of thermophilic bacteria Acetothermia (up to 57.9%), Deinococcus-Thermus (up to 50%), and Aquificae (up to 10.8%). Proteobacteria (29-77%) and Firmicutes (15-26%) dominate in the sulphide-free Garga spring (73-75°C). The functional analysis of the microbial community showed that the primary producers are cyanobacteria, anoxygenic phototrophs, and chemolithotrophic bacteria. At the terminal stages of the mineralization of organic matter, sulphate-reducing bacteria are the main destructors in the microbial communities in hot springs. The cyano-bacterial and sulfidogenic microbial communities play an important role in the formation of geochemical barriers and mineral formation.

Bacterioplankton community taxonomic composition of four large freshwater lakes of the Yeravninskaya depression (Bolshoye Yeravnoye, Gunda, Isinga, and Sosnovoye) which have great fishery significance for the region has been studied. The microbial community consists in the main of bacterial phyla Gammaproteobacteria (22-74%), Actinobacteria (4-35%), Firmicutes (1.17-34.6%), Bacteroidetes (0.3-7%), Cyanobacteria (0.9-6.5%) and Planctomycetes (1.5-10.5%). Total dissolved solids and sulphates accounted for 57% of the variation in the microbial community distribution. At the genus level, Acinetobacter dominated (average 21.4-25.2%). Pseudomonas, Exiguobacterium, and Massilia were also widespread. Their predominance may indicate a possible change in the structure of the community caused by natural and anthropogenic factors. In lakes Isinga and Gunda, a large number of bacteria of the genus Klebsiella was observed, Staphylococcus and Streptococcus were detected. These features indicate insufficient water quality as a result of anthropogenic impact.

Three large freshwater lakes located in the Baikal region (Gusinoye, Shchuchye, and Kotokel) with high touristic significance were studied. Increased anthropogenic pressure is one of the most important causes of water quality deterioration (in particular, high solute and nutrient loads, high productivity). The structural features of microbial communities associated with an increased anthropogenic load have been revealed in different environmental gradients. It was shown that the genera Rhodobacter, Polynucleobacter, and Luteolibacter preferred environments with a higher trophic level and are indicators of possible anthropogenic impact.

The results of studies of the chemical composition of water, travertine, and microbial mats in the Khoito-Gol mineral spring (Eastern Sayan) are presented. It was shown that the formation of mineral deposits, travertine, and microbial mat is connected with the active functioning of microorganisms and geological and geodynamic conditions. It has been revealed that the diversity of cyanobacterial and sulfur microbial mats increases as the distance from the springs of the thermal water grows. Microbial mats are hardened with carbonates being converted into solid travertine crusts that are built upon the top of older structures to form multi-meter domes. The concentration function of the microbial mats and thermal water showed higher coefficients of accumulation of nickel and beryllium.

We studied the taxonomic diversity of microbial mat in the Uro hot spring (the Baikal rift zone, BRZ) with temperatures of 62°C (Ur-3) and 56°C (Ur-4). According to the results of high-throughput sequencing, the composition of the community is represented by various phylogenetic groups Cyanobacteria, Proteobacteria, Deinococcus-Thermus, Chloroflexi, Firmicutes, and Bacteroidetes involved in different stages of organic matter production and degradation in microbial mats. According to metagenomic analysis, there is a wide variety of natural peptidases, enhancing the potential of their specialised functions of energy and substance conversion in microbial mats.

A study of antifungal properties of violacein-forming strain Janthinobacterium sp. B-3515 as well as its secondary metabolite, violacein, against Alternaria brassicicola F-1864 is presented. Regardless of the presence of bacteria, mycelium growth in the first two days proceeded at the same rate. The effect of the bacterial strain was manifested after the third day of incubation. In general, during co-culture, the bacterial strain statistically significantly reduced the average growth of the mycelium of the mould fungus by 10%. The average growth of A. brassicicola F-1864 was decreased in the presence of an aqueous solution of violacein in the nutrient medium (1%, 3%, and 5%). The pigment in 5% concentration had the greatest effect, as the difference between the average growth of the control group and the experimental group was 18%. The mycostatic activity of bacteria of genus Janthinobacterium and violacein against mould fungus Alternaria brassicicola F-1864 was shown for the first time.

The adaptive strategies of biogeochemical systems are considered as a criterion for natural fluctuations of the territory using the example of the microbial community in meromictic soda Lake Doroninskoye (Transbaikalia, Russia). The features of the phylogenetic and functional diversity of the microbial community of the lake have been investigated. In the off-season, a change in the dominant component of the community in the chemocline of the lake was established. During the ice period, the lake is dominated by metabolically flexible, anoxygenic, photoheterotrophic non-sulfuric purple bacteria Rhodospirillaceae and Rhodobacteraceae (class Alphaproteobacteria), which can switch from anoxic photosynthesis to aerobic chemotrophic metabolism. During the open water period, facultative aerobic bacteria of the families Enterobacteriaceae (class Gammaproteobacteria) and Alcaligenaceae (class Betaproteobacteria) predominate, which switch to denitrification in the absence of oxygen.

With the aim to find endophytic actinomycetes that synthesize bioactive compounds over 800 strains were isolated from 53 desert plants of the Gobi-Sumber, Umnugobi, Dundgobi, Dornogobi, Bayankhongor, and Gobi-Altai provinces of Mongolia. The HPLC study of strains with high anti-quorum sensing and antibacterial activities revealed that they produced flavonoids and phenolic compounds. Molecular diversity evaluated with 16S rRNA gene sequences of 123 strains showed that they belonged to 12 genera: Streptomyces, Promicromonospora, Micromonospora, Streptosporangium, Kribbella, Pseudonocardia, Nocardia, Micromonospora, Saccharothrix, Friedmanniella, Actinocatenispora, and Geodermatophilus, the latter two genera were registered in Mongolia for the first time. Moreover, the genus Actinocatenispora was isolated from plants for the first time.

We studied freshwater Lake Dikoye located in the coastal zone of Lake Baikal. Negative changes associated with cyanobacterial bloom were observed in the lake. Phototrophs were represented by cyanobacteria, green algae, and diatoms. In the microbial community, Cyanobacteria were the dominant phylum and accounted for up to 48% of the total diversity. Cyanobacteria were represented by 7 genera and 9 species. Microcystis aeruginosa, a potentially toxic species, was dominant among cyanobacteria. According to chlorophyll a content, the lake should be assigned to eutrophic ones. The bacterial eutrophication index for the lake studied varied from 1.17 (middle eutrophic) to 28.2 (hypereutrophic) during cyanobacterial bloom.

This study determined for the first time the changes in leukocyte composition of the pronephros (head kidney) of sand sculpin Leocottus kesslerii, (Sideleva, 2001) (Lake Gusinoye, Lake Baikal basin, Eastern Siberia, Russia), infected and uninfected with hemoflaggellates of the genus Trypanosoma. The results indicated that the trypanosomes modulated the development of the immune response of their host (suppression of B cell immunity and granulocytic reactions, activation of the leucopoiesis and monocytopoiesis). Selective suppression of immune response in host with trypanosomes promotes the survival and development of parasites.

The data on the morphology and relative abundance of nematodes in bottom-pelagic cottids Cottocomephorus grewingki and C. inermis met in Lake Baikal are presented. Three species of nematodes (Comephoronema werestschagini, Ichtiobronema hamulatum, Contracaecum osculatum baicalensis) were found. The differences in cottids invasion with nematodes are shown.

Inter-annual variations in the total number of birds in floodplains of rivers are mainly associated with their flooding. The minimum population density during the nesting period was in a year with high and prolonged spring floods. The restoration and maximum development of shrubs took place with a significant simultaneous increase in the abundance of birds in subsequent years. Drying and simplification of vegetation cover were noted in all floodplain bird habitats during low-water periods. This process was accompanied by a decline in the number of birds. We identified four groups of bird species according to the criterion of the relationship "abundance – level and duration of the flood". In the first group of bird species, abundance increased during high floods (3 species). In the second group, the abundance decreased sharply during high and prolonged floods (7 species). In the third group, the level and duration of the spring flood did not affect the abundance (9 species). In the fourth group, a very weak tendency of the negative flood level impact on the abundance of birds was noted (6 species).

Abiotic factors affecting the choice of spawning sites for the Baikal omul (Coregonus migratorius) in the Selenga River over 27 years were studied. A total of 3,450 samples were collected using the Dulkeit scraper in Decembers of 1987-2014, at 24 trans-sections in the Selenga River channel over a total length of 410 km. At each sampling site we recorded omul egg density, substrate particle size, water depth, water flow velocity, and ice thickness. Omul eggs were found mainly on hard substrates (sand, gravel, pebbles, and pebble-cobbles combinations). Omul has been found to avoid spawning at depths less than 1.5 m and greater than 6.0 m. Water velocity and ice thickness did not strongly influence the choice of site. Omul eggs were found at flow rates of 0.05-0.7 m/s with a maximum at 0.1 m/s.

Ground beetles are sensitive to environmental changes. We analysed the consequences of haymaking and cattle grazing on communities of meadow ground beetles in Barguzin State Reserve. We assessed community structures during 12 years of the anthropogenic disturbance and after its cessation. The number of categories, types, and variants increased. A decrease in species diversity, a rearrangement of the composition of dominant species, an increase in the relative abundance and share of participation of dominants in the carabid community observed. Of nine dominant species of ground beetles six showed increase of the population number, while others were stable.

We report for the first-time occurrence of three species from the genus Orthosia – O. ariuna Hrebl., O. askoldensis Stgr.; O. ella Butl., and a species Anorthoa munda Den. et Schiff on the territory of Western Transbaikalia. The faunas of these spring species are similar between Western and Eastern Transbaikalia (70%) and close to the fauna of the Far East (50%).

Based on the studies conducted in 2012-2020 on the key plots of mixed fir tree woodlands that grow within the Ulan-Burgasy Mountain range, the authors identified a special nemoral group of lepidopterans, that typically inhabit ocean coastline mixed and broad-leaved forests. Another peculiarity of this area is the presence of species atypical for the major part of the Transbaikal Region: Spialia orbifer Hbn., Leucodonta bicoloria Den. et Schiff., Furcula bifida Brahm (Sub-boreal group); Laothoe populi L. (Central Palearctic group); and Feralia sauberi Graes. (Palearchearctic group). The comparison of Lepidoptera faunas on the key plots and other forest and forest-steppe habitats in the Transbaikal Region revealed their high similarity (more than 80%) to the Ulan-Burgasy humid forests that grow near Baikal and mixed fir tree taiga forests of the Khamar-Daban Ridge.

The history of the Western Transbaikalia terrestrial fauna of small mammals from the Neogene to the Holocene was traced based on fossil-bearing localities. The main factors influencing the development of the Transbaikalia biota and the environment were the gradually increasing climate cooling and aridization for the last four million years in the region.

The purpose of the research is to study the features of the abundance of the chortobiont insect community in the burnt and unburned plots of the plain grasslands of the Torey depression in Southern Transbaikalia. In a number of cases, the diversity in the burned-out plots turned out to be significantly lower. This tendency remains throughout June and July, suggesting the importance of dry, dead grass, which serves as a shelter for invertebrates, providing better protection from predators and high temperatures. However, the species Trigonotylus longitarsus (Hemiptera, Miridae), on the contrary, showed an increase in abundance in the burnt plots.

The species composition and abundance of plants in the Turuchan pika habitat and in its haypiles were studied in the talus surrounded by taiga on the Primorsky ridge. With the Ivlev's Electivity Index, it was found that the pika was selective in collecting food: Veratrum nigrum and Urtica dioica, being relatively rare in the habitat, were highly preferred and abundant in the haypiles. The bulk of the haypiles also consisted of 4 species (Rubus matsumuranus, Sambucus sibirica, Populus tremula, Spiraea media) with a high abundance in the habitat and collected proportionally with their abundance. Many plant species being abundant in the habitat were not stored by pikas.

There is little data available on the zoobenthos of the Baikal region's eastern periphery water bodies in low-water years. The taxonomic diversity of zoobenthos of the littoral zone of a deep lake (Arakhley, Transbaikalia) was studied in an extremely low-water year, 2017. The zoobenthos of the lake littoral zone was represented by 44 taxa. Chironomids accounted for 41% of the zoobenthos taxonomic diversity, 14% each – gastropods and leeches. The taxonomic diversity of the littoral zoobenthos in different parts of the lake varied from 19 to 24 taxa and averaged 22.3 ± 1.97 taxa. The relationship between taxonomic diversity and depth in Lake Arakhley is described by polynomial dependence. Deviations from the relationship identified at the periphery of vegetation thickets were due to the ecotone effect. Obtained data shows the state of zoobenthos taxonomic diversity under conditions of climate aridization and the reduction of littoral sandy habitats.

In laboratory experiments, purposeful predatory inter-relations with moving insects have been revealed and described in three species of herbivorous voles: the East European vole, the narrow-headed vole, and the Tuva silver vole. The appearance of the full hunting stereotype in these species does not require preliminary experience, which indicates its innate nature. The hunting behaviour of the Tuva silver vole differed from that of the East European vole and narrow-headed vole, which probably reflects the phylogenetic relationships between these species.

The taxonomic composition of the fauna has 577 species (608 subspecies) from 76 genera, representing 1% of the total fauna of the world and 5% of the Palearctic fauna. Most genera of ground beetles in the region have a predominantly Holarctic distribution, less often – Palearctic, tropical, or worldwide distribution. The fauna of the ground beetles of the region is based on the genera Amara, Bembidion, Pterostichus, Harpalus, and Carabus. The following genera are important for the fauna of ground beetles in the study region: Dyschirius, Agonum, Nebria, Cymindis, Dicheirotrichus, Poecilus, Trechus, Notiophilus, Elaphrus, Cicindela, Cylindera, Pogonus, Chlaenius, Pseudotaphoxenus.

With regard to the problem of restoring the muksun (Coregonus muksun) population in Western Siberia by means of artificial regeneration, the genetic differentiation of natural populations and broodstocks of fish rearing farms "Forvat" and "Sobsky" was studied. Eighty-four sequences of mtDNA (3,006 bp) containing the highly polymorphic genes ND1 and ND2 were analysed. The differences between the populations of Western and Eastern Siberia were revealed. These findings must be taken into account when attempting to restore the species population in each particular region. The genetic closeness of the muksun from fish rearing farms "Forvat" and "Sobsky" with muksun from the Ob-Taz basin gives grounds for using these broodstocks for seeding the Ob and Taz rivers.

The results of studying taxonomic relationships between five species of the aggregate Leymus secalinus (Georgi) Tzvel. of the genus Leymus Hochst. are presented. The research is based on the study of the ITS1-5.8S-ITS2 region obtained by sequencing the nuclear ribosomal DNA internal transcribed spacers, and on the anatomical and morphological data. A molecular-genetic study of the L. secalinus aggregate has revealed that the two species L. ovatus and L. jenisseiensis are artificial.

The cyclical nature of long-term changes in the annual amounts of atmospheric precipitation in Transbaikalia controls most of the processes in ecosystems. The paper briefly describes the long-term vegetation dynamics of soda lakes in the southeast of Transbaikal territory. These dynamics are driven by changes in abiotic parameters of the lakes, mainly water salinity and pH values. When the values of these indicators increase, the perennial succession series of vegetation of higher plants is as following: Helophytes + Neustophytes + Hydatophytes → Helophytes + Hydatophytes → Helophytes. The succession series of macrophytic algae is as following: Stigeoclonium sp. or Spirogyra sp. → Cladophora fracta + Charophyta → Enteromorpha intestinalis.

The characteristics of the photosynthetic apparatus of coniferous growing in various forest types and climatic conditions of the Irkutsk region (Taishet, Bratsk, Shelekhov, Irkutsk districts) have been explored. The content of photosynthetic pigments, total, free, and bound water in the needles of P. sylvestris and L. sibirica were studied. Using a pulse fluorimeter PAM 2500 (Waltz, Germany), the chlorophyll fluorescence in needles was measured based on such induction curve indices as Fv/Fm, Y(II), NPQ, and ETR. According to the chlorophyll fluorescence induction curve parameters of Scots pine and Siberian larch needles growing in different forest growth conditions, the most effective potential of primary photochemical processes in PSII was observed in Scots pine. While studying the pigment fund of Scots pine and Siberian larch needles, it was found that the highest values of the content of chlorophyll (Chl) a, b, and carotenoids were observed in P. sylvestris and L. sibirica growing in the climatic and forest growth conditions of the Shelekhov district. It is assumed that the revealed characteristics of the parameters reflect the processes of adaptation of the photosynthetic apparatus to various environmental conditions during vegetation development, as well as its high plasticity in different climatic growth conditions.

Waldsteinia Willd. is a small herbaceous genus presumably of Neogene age and formerly wide-distributed around the Northern Hemisphere and now presents the remnants of the tertiary flora. According to the latest taxonomic revision, Waldsteinia is considered a group nested in Geum L. A comparatively low level of morphological divergence together with fuzzy ploidy patterns within Waldsteinia could not be reliable evidence to establish the former distributions and migration pathways of species. In the present study, using plastid DNA (trnH-psbA) data we tried to throw light on Waldsteinia history. Based on our data we believe that the taxonomic decision of nesting Waldsteinia in Geum does not reflect the complex structure of the obtained clade. The phylogenetic analysis showed that the objectivity of previous division Waldsteinia on two subgenera, Waldsteinia and Comaropsis (Rich. ex Nestl.) Teppner, which was based on morphological differences, is becoming controversial. We also suggest an East Asian origin of Waldsteinia and subsequent speciation and taxa distribution in the direction of Europe and North America. W. ternate s.l. (traditionally including W. maximowicziana, W. ternata, and W. trifolia) is appeared to be a polyphyletic group and at least W. maximowicziana should be considered a distinct species.

The quantitative assessment of ecosystem diversity is a basic tool for the evaluation of its resilience to anthropogenic loads and climatic changes. Our work is devoted to the large-scale predictive ecosystem mapping of hard-to-reach West Altai Mountain areas as well as vegetation, soil, and ecosystem quantitative diversity assessment (basing on Shannon and Simpson indices). The key site (7x4.5 km area) located in the Tigirek State Natural Reserve in the humid climate of the windward part of Altai. The predominance of shrub meadow communities and forb meadows on Gleyic Chernozems and Gleyic Chernic Phaeozems, Gleyic Cambisols, as well as the development of larch forests on the slopes of shady exposures on Greyzemic Chernozems are the regional specificities of the forest-steppe Altai ecosystem. Steppe communities (located on the Haplic Chernozems, Cambisols, and Leptosols), occupy less than 2% of the key site. The studied mountain forest-steppe ecosystem of West Altai is characterized by an extremely high level of spatial diversity: the Shannon index is 3.28, the Simpson is 0.95; an increase in soil diversity leads to a linear increase in vegetation diversity.

Herewith the current characteristics of the bog vegetation on the Chaivo spit in the north of Sakhalin are outlined. The many-year surveys have discovered icy permafrost at a depth of 45-70 cm which leads to the formation of annual and perennial migratory pingos. Herewith a brief description of the changes of the pingo vegetation is provided, it has been discovered that the process of lichen growth on the pingos is of selective nature. It has been noticed that some pingos on the bogs of the Chaivo spit have increased in size, which obviously demonstrates the process of replacement, firstly, of mosses by lichens, which in their turn are replaced by herbs and mall shrubs, i.e. pingos on different phases of development can be found. During the period of the surveys, it has been identified that the share of perennial pingos covered with lichens has increased.

The methods of biological species identification using nucleotide sequences of short genome regions (DNA barcoding) are actively developed. The universal DNA barcode for plants remains to be discovered, and one of the leading candidates is the plastid gene of the large subunit of ribulose-bisphosphate carboxylase gene (rbcL). In our study, we estimated the part of rbcL gene as a possible marker for molecular identification of Rhaponticum carthamoides (Willd.) Iljin. Due to its officinal properties, the species is susceptible to uncontrolled and illegal harvesting from natural populations. Today, the species needs to be protected and therefore is included into the Red Data Books of the Russian Federation and certain regions. The study was carried out using plants from the natural populations sampled from the Khamar-Daban Ridge (South Siberia) and considering now as Rh. carthamoides var. chamarense (Peschkova) O S Zhirova. It was shown that rbcL gene can be used to identify Rh. carthamoides at least from the populations of the Khamar-Daban Ridge using a fragment of the maximum length or its 3' region. Apparently, the 5' region of the gene (rbcLa) most often used as DNA barcode for plants may be of lesser importance for Rh. carthamoides. The rbcL gene sequences can be also used for the development of approaches for Rh. carthamoides identification in the medicinal preparations and products containing dried tissues to prevent their falsification and illegal harvesting of this species. The combination of rbcL gene with additional markers seems to be highly desirable to create effective DNA barcodes for Rhaponticum species.

This paper represents the results of the GC-MS analysis of the essential oil's composition of Artemisia jacutica Drob. collected within the Republic of Buryatia in 2015-2020. A. jacutica is an East Siberian endemic plant which has been widely used in folk medicine of Yakutia for the treatment of gastrointestinal diseases. 59 compounds were identified in total, which were represented by mono- and sesquiterpenoids. Neryl-2-methylbutanoate, neryl-hexanoate, γ-eudesmol, and chamazulene were constant components of the oil, whereas γ-eudesmol and chamazulene predominated (the content reaches over 40%). Essential oils of A. jacutica collected in different years were characterized by a stable set of dominant constituents, while the content of sesquiterpenoids was over 92%. The samples of the 2018-2020 years of collection had a greater variety of constituents (31-36 compounds): derivatives of nerol, geraniol, 1,8-cineole, seline-4-diene, compared to the 2015-2017 samples.

The article presents the results of applying the radiophysical method for modelling the dielectric permittivity on the example of Haplic Chernozem Molliglossic soils in the south of the Vitim plateau, depending on VHF and UHF wavelengths, temperature, and soil moisture. Depending on the heterogeneity of moisture reserves and heat content, the soil is considered as a three-layer medium with different soil characteristics. A difference in the frequency dispersion of the complex dielectric permittivity over the entire soil profile in the VHF and UHF ranges has been established.

To clarify the probable role of the stage of the post-lake soil in the evolution of clay-illuvial frozen chernozem the studies were carried out in the southern Vitim plateau of Transbaikalia. The research covers soils in the area of ancient currently dried lakes and the lakeside plain of the Yeravninskaya depression. The obtained data evidence the dissimilarity of parent rocks, as well as radical differences in the soils' characteristics and properties.

Humic substances of soils are considered as a multicomponent system of amphiphilic (exhibiting both hydrophilic and hydrophobic properties) substances. Humic substances from soils of different genesis in the south of the Vitim Plateau (quasigley chernozem – Turbic Chernozem Molliglossic and brown soil – Stagnic Phaeozem Molliglossic) were studied. Using the hydrophobic interaction chromatography on Octyl-Sepharose® CL-4B, we separated a mixture of humic (HAs) and fulvic acids (FAs) due to their different ability to enter into hydrophobic interactions with the gel matrix. A higher percentage of hydrophobic compounds was revealed in HAs of quasigley chernozem, compared to HAs of brown soils, and FAs. The fulvic acid sample showed a lower capacity for hydrophobic interactions than the humic acid sample.

New data on the soils of mountain floodplains in the tectonic joints zone of the Mongol-Okhotsk Orogenic Belt on the example of the Upper Kerulen Basin are presented. Soil diversity is mostly determined by sedimentation conditions and drainage of the parent rocks. There are alluvial–humus (Fluvisol (Humic)), mucky–humus (Folic Fluvisol), dark–humus (Fluvisol (Mollic)), dark–humus gley (Gleyic Fluvisol) and dark–humus saline soils (Sodic Gleyic Fluvisol (Mollic)) were diagnosed. Tectonic movements of the earth's crust lead to the appearance of shaftlike linear dams, blocking river flow through the valley. So, the Kerulen river changed the direction of the channel and go beyond the depression, embedding into its mountain frame. Current seismicity impact on soils appears locally at tectonically active positions of epigenetic areas, close to outputs of saline underground deep waters, in the form of surface soil salinity and hydrometamorphism.

The intensity of microbiological processes in soils of pingos and thermokarst depressions in the south of the Vitim Plateau was studied. The number of dominant groups of microorganisms (Fungi; Bacteria, and Actinomycetes as a separate group) in Haplic Chernozems (Stagnic, Turbic) and Calcaric Gleyic Phaeozems were identified. Carbon accumulation in microbial biomass in soils of pingos and thermokarst depressions varies considerably in comparison with background soils. Bacterial microflora has been proven to prevail in soils under the study. The maximum indicators of actinomycete and fungal mycelium were found in the soils of thermokarst depressions. Microbiological activity for all studied parameters is higher in Calcaric Gleyic Phaeozems.

We described the taxonomic structure of planktonic associations in the water bodies of Kharanor State District Power Plant (cooling pond, water supply, drainage, and water intake channels of Kharanor reservoir located in the arid zone of the south-eastern Transbaikalia in a highly continental climate). Hydrobiological researches were conducted in April, July, and October 2019. We identified 141 algal taxa ranked below the genus, representing the divisions of Cyanobacteria (15 taxa), Bacillariophyta (41), Chrysophyta (10), Cryptophyta (3), Dinophyta (4), Charophyta (8), Chlorophyta (56), and Euglenophyta (4), and 52 zooplankton taxa, including 28 species and subspecies of Rotifera, 15 species of Cladocera, and 9 species of Copepoda. In the cooling reservoir, the plankton community included 135 phytoplankton taxa and 38 zooplankton species; 58 algal taxa and 27 invertebrate species were sampled in the water supply channel, 50 taxa and 26 species were sampled in the drainage channel, and 94 taxa and 24 species were collected from water intake channel respectively. Six diatom species (Stephanodiscus hantzschii, Nitzschia sigmoidea, Fragilaria radians, Asterionella formosa, Ulnaria ulna) and four zooplankton species (rotifers Asplanchna priodonta and crustaceans Daphnia galeata, Bosmina longirostris, Thermocyclops crassus) occurred in all water bodies during the entire study period.

This study reveals temperature regimes of the three contrasting ecosystems in the permafrost area of Western Transbaikalia: meadow-forest ecosystem, forest-steppe and dry-steppe. Annual profile temperature data show the functioning of the studied soils in cryogenic and long-term-seasonally-freezing temperature regime. The most explanatory temperature variables are temperature penetration above 5°C at 100 cm depth and the amount of days with temperature above 0.5°C and 10°C at 20 cm, 50 cm, and 100 cm depths. Also, this work presents a comparative analysis of indicators of soil climate change and shows the spatial-temporal distribution of the reaction of the thawing and freezing depth in soils.

At the Bureiskoe Reservoir (Far East, Russia) in December 2018 at a temperature of 36°C below zero the giant landslide is occurred. Landslide with a total volume of 24.5 million m³ blocked the reservoir from one shore to the opposite one, disrupting the access of water to a large hydroelectric power station downstream. Blasting operations were carried out with the use of trinitrotoluene and hexogen to revive the water flow. As a result of the landslide natural hazards (direct impact of the landslide, and tsunami) were happened, and the further strong impact was caused by humans (blasting). Volatile organic compounds (VOCs) and elemental composition were accepted as the main indicators of water quality. Parameters of these indicators varied at different near-shore sites above and below the landslide area. More significant changes are recorded after blasting operations. Hexane and toluene dominated the water passing the artificial channel. The genesis of VOCs can be associated with the biogeochemical processes of methanogenesis, methanotrophy, and the detonation products of explosives. Mercury, methanol, toluene, and xylenes in water samples were detected. This is evidence of the presence of a prerequisite for the formation of toxic methylmercury, a risk factor for aquatic biota.

In the soil cover of technogenic territories (Usolye-Sibirskoye, Irkutsk Region, Eastern Siberia, Russia) the initial, organo-accumulative, soddy, and humus-accumulative embryozems were identified. The period of soil formation was established: from 20 years (organo-accumulative) to 40 years (humus-accumulative embryozems). The relationship between regenerative successions of vegetation and stages of the soil-forming process was found. Each stage of post-technogenic soil formation (type of embryozem) corresponds to a certain type of plant communities possessing a clear discrepancy in the species composition. The first stage is represented by plant communities comprising few ruderal species on the initial embryozem. The more advanced stage is characterized by complex communities consisting of grasses, shrubs, and trees on the humus-accumulative soil. It has been shown that the humus content determines the degree of natural restoration of biocenotic functions in the post-technogenic ecosystem. Plants-concentrators that can be effectively used in phytoextraction of metals for decontamination of embryozems have been studied. Natural renewal of vegetation and the development of soil-forming processes serve as the best option for the rational use of nature management in comparison with the artificial restoration of natural landscapes in technogenic territories.

Maintaining an ecological balance of Lake Arey is crucial in terms of nature conservation. Lake Arey is located in Eastern Siberia and is a central object of a designated conservation area of regional significance. The lake is used for recreation (organized and unorganized tourism, sport fishing, mud collection for balneological purposes) not only by residents but also by holidaymakers from other regions. In terms of mineralization level, Lake Arey is a freshwater body. Significant factors affecting the aquatic ecosystem are temperature, TDS, pH and dissolved oxygen, depth, and turbidity. High contents of ammonium ions are observed in the ecosystem. The concentration of dissolved inorganic phosphorus is 23.6% of total phosphorus. The ratio of PO (permanganate oxidizing ability of organic matter) to COD (chemical oxygen demand) indicates active processes of production, mineralization, and transformation of organic matter in the water body. Carotenoids prevail in planktonic pigments. The chlorophyll a amount is insignificant. The chlorophyll b content increases from July to September. Currently, Lake Arey belongs to the α-mesotrophic type of water body. However, increased anthropogenic load and high-water years can promote eutrophication processes.

The studies of urban forests were carried out on the territory of the Angara region in cities with a high air pollution index (up to 20) and with a high recreational load. The state of forest biogeocenoses was assessed by the parameters of trees, forest litter, and soil. Morphostructural, physicochemical, biochemical, and toxicological indicators were analysed. It was found that the selected biogeochemical parameters of trees and soils have a high level of correlation relationships under conditions of negative anthropogenic impact. The biogeochemical redistribution of technogenic pollutants in urban forests connects with the accumulating capacity of the soil cover and the regulatory function of trees, namely the ability to purify atmospheric air by accumulating toxicants in the needles and leaves. Regulatory function/service of pollutant absorption and air purification depends not only on the condition of urban forests, it is unequal for forests of different cities and, even more, for different forested territories.