A biostratigraphic division of the Lower Permian into brachiopod zones of Jakutoproductus verkhoyanicus, Jakutoproductus insignis, Jakutoproductus terechovi, and Jakutoproductus rugosus is observed within the Northern and  Western Verkhoyanie. According to the literature, only the complex of the lower biostratigraphic unit (Verkhoyanicus Zone) was previously confidently established in the Southern Verkhoyanie. Meanwhile, representatives of the two middle zones were not observed, and the presence of the index species of the Rugosus zone was only indicated in the southern part of the region (Yudoma River Basin). A monographic study of the brachiopod collection from the Upper Olchan Subformation of the stratotype of the Olchan Formation (Khospohchon section) allowed us to rethink the biostratigraphic division of the Asselian-Sakmarian deposits in the Southern Verkhoyanie. The brachiopods of the Upper Olchan Subformation of the Khospohchon Creek (Menkule River Basin) belong to three successive biostratigraphic zones: Verkhoyanicus, Insignis, and Terechovi. Information on the presence of representatives of the species Jakutoproductus rugosus Ganelin in the Southern Verkhoyanie leads to the assumption that all four biostratigraphic zones of the Asselian-Sakmarian deposits of Verkhoyanie are present in this region. Three upper zones (Insignis, Terechovi, and Rugosus) demonstrated a direct correlation with the Ogonerian Regional Stage of the Omolon massif by their common zonal species. The new results indicate the need for a comprehensive study of the key sections of the Olchan Formation to substantiate the Carboniferous-Permian and Asselian-Sakmarian boundaries in Verkhoyanie using both biostratigraphic and chemostratigraphic methods.

The traps in outcrops of the middle course of the Morkoka River were formed in three stages and implementation phases. Each subsequent introduction phase of the basite melt was distinguished by its petrogeochemical features, degree of crystallization of the magmatic melt, and density. An unusual form of intrusion introduction in the second phase (crushing of the sill and the introduction of an early intrusion into the rocks) was revealed. During the formation of kimberlite diatremes, the carbonate rocks containing them became denser and thermoelastic stress fields associated with the magnetoelastic Villari effect arose. As a result, the so-called “protective shield” was formed around the kimberlites. A comparison of the trap sill behavior of the Morkoka River with the similar behavior of traps near kimberlites (Komsomolskaya and Morkoka tubes) suggests the presence of an unknown kimberlite body under traps in this area.

Limited available data on molecular geochemistry indicate the predominance of terragenous organic matter in the source material of the Lower Cretaceous deposits of the Ozhoginskaya suite, which allows it to be considered gasgenerating. However, based on the mixed nature of the source material, this suite could possess potential for liquid hydrocarbon generation. The geochemical features of the organic matter were studied using classical bituminology, Fourier transform infrared spectroscopy, gas chromatography, and mass spectrometry. The results showed a regular distribution of alkanes with a predominance of low-molecular-weight homologues with a maximum at nC15-19 and low values of ∑n.c.-nC₂₀/∑nC₂₁-c.c., vanadylporphyrin complexes. Thus, the contribution of algal material could be significant to the composition of the fossil organic matter of the Lower Cretaceous Ozhoginsky suite with different ratios of terrigenous and aquatic components in the section. Our results on the Ozhoginskaya suite showed the similarity of geochemical parameters with the Upper Bastakh suite of the Upper Jurassic, the features of bitumoid composition, which were mainly due to the predominance of planktonic-algal material capable of generating a large amount of liquid hydrocarbons. This established similarity raises the estimate of the oil generation potential of the organic matter of the Lower Cretaceous deposits of the Ozhoginskaya suite, along with the high gas generation potential inherent in terragenous organic matter.

The results of the 42-year monitoring of the thermal state of permafrost landscapes in modern climate warming conditions at the “Chabyda” observation station (Central Yakutia) are presented. We studied the evolution of the variability of soil thermal state parameters: the temperature of soils on the sole of the seasonally shallow layer and in the layer of annual heat rotations, and the depth of seasonal thawing. The long-term variability of the average annual soil temperature, experiencing significant interannual and short-term fluctuations, has a multidirectional trend, with warming dominating. The main factors regulating the thermal state of permafrost landscapes are the short-period fluctuations in the snow accumulation regime. Despite significant interannual fluctuations, the depth of seasonal thawing responded to climate warming with multidirectional trends, and its increase or decrease was statistically insignificant. We performed a statistical analysis of the observation time series revealing correlations between climate elements (air temperature, total precipitation, average winter snow depth, duration of winter and summer seasons) and relationships between soil temperature regime parameters (Т_ξ, Т₀, ξ) with climate elements. The results of these studies on the thermal state of soils can be applied to homogeneous landscapes in this region. They can also be used to model heat transfer processes in natural landscapes and develop hybrid intelligence methods for diagnosing the state of infrastructure facilities in the Far North based on high-performance computing systems.

Thermal anomalies in the city, otherwise called “heat islands, “are formed under the influence of anthropogenic factors. In Yakutsk, temperature anomalies were caused by GRES-1, GRES-2, and other industrial complexes. The crowding of residential buildings and structures prevents the movement of air masses and makes it impossible to maintain the condition of the cryolithozone at the proper level, which contributes to the degradation of permafrost in a warming climate. We propose to didentify “heat islands” in Yakutsk using remote sensing methods, based on the data of the thermal infrared range of the Landsat 8 satellite, which provides information with an interval of 16 days. The thermal anomalies in various areas of Yakutsk and its vicinity in summer and winter, which create zones of possible permafrost degradation and affect the geocryological safety of the city, were analyzed based on the proposed methodology. This information will make it possible to monitor the process of changes in the temperature field of a territory and implement preventive measures for the stability of buildings and structures.

This article investigates the content of heavy metals (Cu, Ni, V, Cd, Zn) in the reproductive organs of the Gorodkov’s rowan (Sorbus gorodkovii Pojark.) growing in the impact zone of environmentally hazardous facilities in Murmansk (CHP plants, waste incineration plant and trade sea port). The samples most contaminated by heavy metals were registered in the vicinity of the incineration plant. High concentrations of vanadium (4,2–4,8 mg/kg) and Cu, Ni, Cd, and Zn exceeding the limits of MPC are revealed in the impact zone of CHP plants operating on fuel oil. Biomonitoring of the viability of S. gorodkovii pollen showed that in all samples, the content of fertile pollen grains was reduced compared to that in the control. At the test sites of the Central and South CHP plants, the proportion of fertile pollen was 35–41 % (compared to 72 % in the control sample). The induced sterility was more than two times higher than the spontaneous sterility. High concentrations of vanadium and other toxic metals in emissions of Heating Plants have a gametocidal effect on the male gametophyte of S. gorodkovii. Groups of fertile and sterile pollen grains were selected according to their size: dwarf, normal, or hypertrophied. In the vicinity of the CHP plants, the proportion of fertile pollen of normal size decreased (62–69 %), whereas the content of dwarf (16–18 %) and hypertrophic pollen (17.4–22.7 %) increased. Sterile pollen grains were mostly dwarf (63–70 %). The results of biomonitoring indicated that CHP plants polluted the urban environment with vanadium and other toxic metals, which caused sterilization of S. gorodkovii male gametes. To improve the ecological situation in Murmansk, it is necessary to switch the thermal stations for the use of natural gas.

The effects of permafrost bacterial strains on morphogenesis, rhizogenesis, and photosynthesis in potato micro-plants under in vitro conditions were assessed from 2019 to 2021. We used three bacterial culture strains from the collection of the Cryosphere Bioresources Department, Tyumen Scientific Center of the Siberian Branch of the Russian Academy of Sciences. The study was conducted on microgrowers of three potato varieties: Zhukovsky Early, Rozara and Red Scarlett. Two strains of bacteria were isolated from the cores of perennially frozen rocks. We found that the combined cultivation of potato microgrowers under in vitro conditions on Murasige-Skug nutrient medium with secondary metabolites of the bacterial strains Bacillus cereus 9-08-CH9 and Achromobacter spanius 10-50TS2, introduced at the time of cutting at a dose of 250 µL, had the greatest stimulatory effect on its morphogenesis, rhizogenesis, and photosynthesis. Thus, the proposed cultivation method accelerates clonal micropropropagation of in vitro materials for original potato seed production.

Extreme environmental factors lead to changes in the metabolism of the body and, in particular, to the predominant use of proteins and fats. The aim of our study was to reveal seasonal differences in the blood plasma fatty acid profile of people with evolutionarily developed mechanisms of adaptation to the specific conditions of the North. The subjects of the study were young male aborigines of the North (Yakuts), virtually healthy volunteers whose mean age was 19.1 ± 2.2 (n = 26). Venous blood samples were collected in the morning from 8:00 am to 9:00 am in different seasons (summer, fall, and winter). Temperature variations during these seasons were more than 100 °C. Identification and determination of fatty acid (FA) concentrations in the blood plasma samples were performed using gas chromatography-mass spectrometry (GC-MS). Statistical analysis of blood plasma lipid profile data was performed using MetaboAnalyst 5.0. The results showed that the ratio of unsaturated fatty acids (USFA) to saturated fatty acids (SFA) increases by 1.8 times in winter compared to other periods (summer, and autumn). The leading role of polyunsaturated fatty acids (PUSFA) in the adaptation of the human body to interseasonal changes has been revealed. The most important role is played by the winter increase of 11,14,17-eicosatrienoic acid (omega-3) and the winter decrease of arachidonic acid, cis-11,14-eicosadienoic acid and 8,11,14-eicosatrienoic acid.

This study provides biological and operational data on the reserves of non-timber forest products in the Republic of Sakha (Yakutia), which play an important role in this region. The legal framework and system for harvesting and selling non-wood forest products by the population of the region were examined. We propose directions for increasing the volume of harvested non-wood forest food products, which can contribute to social and economic development in the region. This study employs economic and statistical analyses, situational analysis, and sociological research methods. A forecast for the most common wild berries was made based on the average annual yields harvested by all entities engaged in this type of economic activity. Information on the natural and economic conditions for the use of forest product resources and the possible development of regional markets for valuable natural reserves can be applied to regional studies to develop programs for forested areas. The proposed developments can be used to study issues related to the functioning of the regional market for non-timber forest products.

Scientific information on waterfowl harvesting in Yakutia is mostly outdated. The lack of reliable bag data prevents the establishment of sustainable use of waterfowl resources under the conditions of massive shooting and a modified legislation base. This research aimed to collect and analyze contemporary information on the hunting take of waterfowl (Anatidae, Coot, loons, and grebes) in Yakutia. We used data from the State Hunting Registry (2017–2022) to estimate the total harvest. Species-specific shares in hunting bags were identified using digital photographs of shot birds collected from the Internet in 2015, 2017, and 2018 (around 1000 photos). The distribution and results of traditional spring hunting of scoters were studied through a survey of hunters conducted in 2015. On average, 18,400 geese and 200,000 ducks were shot during the summer-autumn season, whereas 26,600 geese and 160,500 ducks were shot during the spring season. Overall, 23 waterfowl species were identified, namely three species of geese, 17 species of ducks, Coot, Arctic Loon, and Red-necked Grebe. The autumn bag included 22 species, of which the bean goose, mallard, Eurasian wigeon, and common teal were the most abundant. Spring bags consisted of 14 species with prevailing bean geese, common teals, northern pintails, and mallards. Based on “least concern” international and national conservation status we suggest to exclude the Chinese Spot-billed Duck, Gadwall, Common Scoter and Coot from the Red Data Book of the Republic of Sakha (Yakutia) and resume their hunting use.

This article presents the results of forestry and geobotanical studies of post-fire communities in pine forests adjacent to large sandy deserts, tukulans, in the Lena-Vilyui interfluve. Pine forests, which are widespread in the middle and around the tukulans, have recently become highly susceptible to fires, as the entire territory of the Lena-Vilyui interfluve. In 2019, we collected materials on post-fire communities in multi-age burned areas, which supplement a few pieces of information regarding post-fire reforestation. We found that the vast areas of the studied region were occupied by pyrogenic communities. We assumed that the natural regeneration of Scotch pine in the vicinity of tukulans was unsatisfactory, with 0.3–0.95 thousand pieces of pine undergrowth/ha. Post-fire communities can become launching pads for the development of modern aeolian processes or can expand the area of existing tukulans.

This article is dedicated to the study of the structural, electrical, and optoelectronic properties of nanostructured carbon films obtained by methane plasma deposition, followed by annealing at high temperatures (650–800 °C). The conditions for obtaining the films affected the final physicochemical parameters. We studied the film morphology using atomic force microscopy, scanning electron microscopy, Raman spectroscopy, X-ray energy-dispersive analysis, and analysis of the current voltage (C-V) characteristics. The film thickness ranged from 20 to 150 nm, with a C/O ratio of 4:1. Structural studies have shown that the resulting nanostructured carbon films consist mainly of nanographite flakes, the lateral dimensions of which lie in the lateral size (La) range of 5 to 12 nm, and contain different fractional concentrations of sp³/sp² crystalline phases of carbon. We have established that with an increase in the annealing temperature, the defectiveness of the carbon film structure increases; however, at the same time, the degree of graphitization increases, as indicated by the Raman spectroscopy data and the calculated values of layer resistances from the C-V characteristics. The values of photocurrents were calculated, from which it was found that the samples exhibited photosensitivity in the temperature range of room temperature to –173 °C, based on the temperature dependences of the C-V. The obtained results can be useful in creating day and night light sensors as well as temperature sensors suitable for use at low temperatures.

According to current regulations, mammoth tusk (MT) grades are identified based on their appearance (integrity and geometric parameters), without considering their mineralization features, mechanical properties, and humidity. However, these characteristics specify approaches for the storage and bone cutting processing of raw materials. This study aimed to investigate the features of mineralization and the relationships between the physical and mechanical properties of MT and their grades. We studied MT samples from Grades I to IV. Their mineral compositions were determined using X-ray phase analysis. The indicators of maximum moisture saturation and dynamics of the change in mass after drying were identified according to the MT grade. The dependence of the physical and mechanical properties of various grades of MT on their moisture content was established. X-ray phase analysis revealed that MT Grades III and IV differed from Grades I and II in the presence of phosphate mineral impurities. We found that the presence of cracks and pores in the studied samples significantly affected the index of maximum water saturation and nature of moisture loss. The study of the physical and mechanical properties of the MT samples showed that with an increase in moisture content, the compressive strength decreased. We also proved that the physical and mechanical properties of MT did not depend on their grades.