New data on the geological structure and petrochemical characteristics of the first kimberlite pipe in the Syuldyukar kimberlite field and its position in the Ygyatta diamond-bearing area are presented. The petrographic identification of the petrochemical varieties of kimberlites in this area was performed for the first time. The compositions of the rockforming and accessory minerals of kimberlites were studied using a modern hardware complex. The results showed that the directed change in the structural and material characteristics of kimberlites from peripheral to central parts in extended vertical bodies of the Syuldyukar tube type is expressed in the replacement of calcium kimberlites by magnesium kimberlites. Mg-kimberlites are characterized by the largest crystals of diamond, garnets, and ilmenites, high concentrations of magnesium, and a number of other components. All of these changes in kimberlites are caused by flow differentiation. This information allowed us to apply the obtained petrological results to the kimberlites of the Syuldyukar tube as search criteria for forecasting and identifying new kimberlite bodies in the Ygyatta diamond-bearing area.

This article provides data on the identification and distribution of Au-Ag minerals in the tailing dump of the processed ores in the pyrite-polymetallic deposit within the Salair ore field (Talmovskiye Sands, Salair). The mineral and chemical compositions of the samples were studied using atomic absorption, mass spectrometry with inductively coupled plasma, X-ray diffractometry, and scanning electron microscopy. We have established that a horizon of secondary enrichment was formed (with Au and Ag contents up to 5,3 and 53.7 g/t, respectively) over a long period of the tailing dump existence (more than 90 years) and at a depth of 0,6-0,8 meters. Gold and silver are unevenly distributed along the section and are present in three species:1) native (Aus, Ags), 2) mineral (acantite, petrovskaite), and 3) isomorphic (sulfides and secondary films). The identified residual and newly formed gold-silver minerals indicate active supergene processes of Au-Ag dissolution, migration, and precipitation. The transformation of native particles occurs through both chemogenic and mechanical processes.

Oxalates, which are salts of oxalic acid, belong to a large group of organic minerals or biominerals that can occur both in the natural environment and inside living organisms, which makes them valuable for various sciences. We have discovered, for the first time, oxalates in several natural samples from the Daldynsky kimberlite field, the basin of the middle course of the Markha River, and the coastal outcrop on the Allah Yun River. We also confirmed their presence in kidney and gallbladder stone samples in the human body. X-ray phase analysis allowed us to establish the presence of weddellite or whewellite in association with quartz, dolomite, feldspar, mica, and chlorite in the samples under study. Meanwhile, the composition of the kidney stone in the human body represents a mixture of whewellite with uricite, the composition of the stone from the gallbladder includes uricite, whewellite, ammonium urate and brushite. Possible reasons for the formation of one- and two-in-one modifications of calcium oxalates in nature are also discussed. We conclude that these minerals are more widespread than previously assumed.

Cambrian sections of the Lena Pillars National Park and adjacent areas in the south-east of the Siberian platform have been the subject of paleontological-stratigraphic, lithological, facies, paleogeographic and structural-tectonic studies. In this article we provide a detailed description of the Lower Cambrian Pestrotsvet Formation in the off-reef facies near the Oi-Muran reef massif. The description is given by the coastal outcrops of the Lena River above Sinsk village: 27 “Bachyk” (left bank), 43 and 44 (right bank). The exposed sediments in these outcrops belong to the off-reef shallow part of the open normal saline sedimentary basin adjacent to the Oi-Muran fragment (reef array) of the grand West Yakut Barrier Reef. We conducted a detailed description of the typical part of the section to identify the specifics of sediment accumulation in the Pestrotsvet Formation. A thin alternation of limestone laminae (with thickness varying from 3–5 to 10–20, less often 30–40 cm) was established. They are characterized by a light gray clean, pinkish-gray color, without visible impurities, and burgundy clay with abundant admixtures of ferruginous pigments. The individual intervals of the section are characterized by laminae of maroon marlstone. The rhythmic shift in the section of rocks of different compositions is the result of frequent, however, according geological standards, short-term transgressions and regressions. The origin of some laminae of comparatively pure gray and pinkish-gray limestones that contain abundant remains of cyanobacteria and algae is related to the rock-forming activity of these microorganisms. The materials presented in this article contribute to studies on the off-reef facies of the West Yakut Barrier Reef, one of the oldest reefs on Earth, which played a major role in the emergence of reef biota.

The article presents the results of an investigation of the permafrost conditions of the embarkment dam in Yakutsk, which is located in the low floodplain of the Lena River. Dam site 3 rests on thawed soils represented by multi-grained water-saturated alluvial sands of various densities. The measured soil temperature alters from +6 to +6.4°C at a depth of 10 m. The high temperature was attributable to the discharge of warm water from the Combined heat and power (CHP) plant in Yakutsk into the enclosed cooling pond. Electrical resistivity tomography (ERT) is a highly effective geophysical method for delineating seepage zones in the earthen dam body, and determining the upper permafrost table at the base of construction. We have provided recommendations for the static and filtration stability of the study site.

This study aimed to analyze the organic, inorganic, and total carbon contents in Central Yakutia. We selected two sites with similar climatic features: Diring-Atakh (Churapchinsky region) and Syrdakh (Ust-Aldan region). The analysis showed that the decreasing dynamics of carbon stocks was attributive to their depth. The maximum accumulation of carbon was observed in the upper humus-accumulation horizon. We found that the minimum organic carbon content (0.22 % OC) and its maximum content (4.81 % OC) were tracked in the active layer at the Syrdakh site. However, the concentrations of both organic and inorganic carbon in the seasonally thawed layers were marked with a uniform distribution down the profile and a peak increase in permafrost at the Syrdakh site. The obtained results indicate variability in the carbon content typical of the region. The climatic and geological characteristics of the region contribute to the disintegration of carbon in the sediments of the ice complex during systematic thawing and freezing, movement along the profile of dissolved organic compounds, and frost weathering. The ratio of organic and inorganic carbon in permafrost soils is an indicator for rapid assessment of the state and flow of soil organic matter in a changing climate.

This article presents an annotated list of plant type specimens stored in the Herbarium of the IBPC SB RAS (SASY), which is one of the largest in northeast Russia. The Herbarium fund is represented by five departments (vascular plants, mosses, lichens, aphylophore fungi, and algae), where about 95000 herbarium samples are stored exluding algae tests. The Herbarium has a collection of plants from Western and Eastern Siberia, the Far East, and some central regions of Russia. The exchange fund contains more than 3000 species of plants. Typical samples stored in Herbaria are of a particular value. In total, 14 species and 2 subspecies of liverworts, mosses, and vascular plants from 11 families were isolated from the main collection of the SASY Herbarium, which are represented by 14 types, 16 isotypes, 14 paratypes, and 5 epitypes (Frullania ignatovii Sofronova, Mamontov et Potemkin, Barbula jacutica Ignatova, Grimmia jacutica Ignatova, Bednarek-Ochyra, Afonina, J. Muñoz, Aconogonon amgense (V. Mich. et V. Perf.) Tzvel., Androsace gorodkovii Ovcz. et Karav., Anoplocaryum elenae Volot., Artemisia karavajevii Leonova, Astragalus zhiganicus L. Kuzn., and Castilleja galactionovae E.G. Nikolin, Castilleja rubra (Drob.) Rebr. var. multicaulis E.G. Nikolin, Castilleja tenella Rebr., Oxytropis scheludjakovae Karav. et Jurtzev, Rosa acicularis Lindl. subsp. melanocarpa L. Kuzn., Sorbocotoneaster pozdnjakovii Pojark. var. cotoneaster L. Kuzn. et Volot., S. pozdnjakovii Pojark. var. sorbus L. Kuzn. et Volot., Salix x zhataica Efimova, Shurduk & Ahti). Plants, the types of which are stored in SASY, represent the indigenous flora of Yakutia and are found quite rarely in this territory; eight of these species are listed in the Red Book of the Republic of Sakha (Yakutia), and 11 species are endemic. For each sample, a quote of the original label is indicated, and a brief ecology, distribution, and rarity category is given. The originality of the publication of each standard sample is indicated by the images of digitized herbarium sheets and their labels.

A unique project on the hybridization of domestic sheep with wild bighorn sheep of the Yakut subspecies (Ovis nivicola lydekkeri) was implemented under extreme conditions in Yakutia. Hybridization was performed to obtain new forms that combine productive indicators with specific adaptation qualities to harsh breeding conditions. Viable hybrids of both sexes were obtained via laparotomy during the artificial insemination of domestic sheep with frozenthawed epididymal male bighorn sheep. We compared the hybrids with domestic lambs. At birth, the hybrids had a live weight of 2.65±0.19 kg, which is 29 % less than that of domestic lambs. A difference in live weight was noted before reaching the age of 20–24 months; however, by 36 months, hybrid males outnumbered domestic rams of the same age. We found that in the early postnatal period, hybrids were satisfied with their mothers’ milk faster and more often, and their daytime sleep was short and shallow. The hybrids also showed a high degree of curiosity, jumping ability, caution, and clear imitation of the mothers’ behavior. In terms of growth and development, the hybrids were tall and narrow-bodied because of their high mobile activity, as well as differences in nutrition. The hybrid offspring differed in chromosome set from the parental forms, having a diploid set equal to 2n = 53, whereas the maternal form of the sheep had 2n = 54, and the paternal form had 2n = 52. The resulting hybrids are fertile, and differ from their peers in the dynamics of development, nutrition, and ethology. They have phenotypic features similar to those of the paternal form, and a new improved form of the genotype is the basis for selection in sheep breeding.

This study investigated the composition and properties of the main soil types in the natural biogeocenoses of tundra and taiga in the coastal lowlands of the Arctic zone of Northern Yakutia. We have identified the total content of biologically important chemical elements in the soils and resource plants (N, P, K, Ca, Mn, Zn, Cu, Co, Mo, B, As, Be, Cd, Cr, Ni, Pb, Hg, V, Sb, and Sr), and the concentration of mobile forms of S, P, K, Fe, Mn, Zn, Cu, Co, Cd, Cr, Cr, Ni, and Pb in different extractants. We also specified the influence of soil composition and properties on the content of macro- and microelements. Various mobilities of chemical elements in soils and their availability to plants have been revealed. The amounts of chemical elements in the studied soils and plants were estimated according to agrochemical, biogeochemical and hygienic criteria and standards.

This paper presents an investigation of previously unstudied soils of the Arctic islands (Krestovsky and Chetyryokhstolbovoy), which gained the status of a new protected area “Bear Islands” (70°37′–70°60′ N, 160°23′–162°33′ E). Their soils were formed mainly under permafrost conditions (approximately 1 m), with a seasonal thawing depth of 0.3–0.6 cm. The territory of Krestovsky Island is a combination of several landscapes characterized by various types of permafrost soils. Primitive gravelly soils (A–BC(C)) are exposed in mountainous areas. Permafrost tundra low-gley soils (OT–Bg–BCg(C)) are formed on the gentle long slopes under hummocky moss-herbaceous tundra. In natural depressions on cryogenic forms of surface, the soil cover represents a combination of permafrost arctotundra gleyic (O–B–Bg(BC)┴) and humus-gley soils (O–AH–AB–BG┴). Marsh soils (Ad–C(AC)–C′) occur along the low flooded gently sloping coasts of the island. All soils are acidic. Zonal types are characterized by gleying, which brings them closer to the soils of the mainland. The soil cover of Chetyryokhstolbovoy Island, with the most fully developed shrublichen-moss or forb-moss soils, is rather monotonous. Namely it is represented by arctotundra gleyic soils with a profile of the same type in terms of morphological features and physicochemical properties (О–Аd–АВ(g)–Вg(BCg)). The main features of this soil type include the thinness of the surface organogenic horizon, good decomposition of organic matter, high and medium content of humus in the soddy-humus horizon, the absence of surface gleying or its weak severity due to drying out in summer.

The phosphate state of six types of frozen soil in Central Yakutia (forest podzolic, pale brown and pale, meadowsteppe chernozems, meadow-chernozem, and chernozem-meadow) was studied for the first time. We estimated the total phosphorus content and intra-profile distribution, and calculated the forms of mineral phosphates using the Chang-Jackson method and mobile phosphates according to Ginzburg-Artamonova. The weighted average total phosphorus content in these types of soils was low (174–376 mg/kg). The highest amount of total phosphorus was observed in permafrost meadow-chernozem (376 mg/kg), chernozems (358 mg/kg), and pale (344 mg/kg), slightly lower in chernozem-meadow (302 mg/kg), and the lowest was in pale-brown (214 mg/kg) and podzolic soils (174 mg/kg). Under cryolithozone conditions in Central Yakutia, which is characterized by a cryoarid climate and continuous permafrost, cryogenic soils are characterized by low biological activity and, consequently, a low amount of phosphates available to plants. The mobile phosphate content in the studied frozen soils (1,3–7,4 mg Р₂О₅/100 g soil) was low and very low according to Ginzburg-Artamonova (not exceeding 1–2% of the gross content). The upper horizons of frozen chernozems, which are the warmest and most fertile soils in Central Yakutia, have the amount of phosphates (18,3–42,1 mg Р₂О₅/100 g soil), which makes 8–1 % of the gross content and is estimated as medium and high. In various genetic horizons of frozen soils in Central Yakutia, the total amount of all forms of mineral phosphates estimated accrording to Chang-Jackson varies widely and ranges from 11,4 to 188,0 mg Р₂О₅/100 g soil. The studied frozen soils also differ in the minimum content of the most loosely bound phosphates available to plants, amounting to 2,7–6,0 mg Р₂О₅/100g soil, which usually does not exceed 10 % of the total amount. We conclude that the fractional composition of mineral phosphates in the frozen forest soils of Central Yakutia is dominated by phosphates that are difficult for plants to reach. The maximum content of iron phosphates reaches 63,1–92,6 % of the total amount of all fractions. A relative increase in calcium phosphates to 56,5–58,0 % of the total content is observed in the frozen meadow-steppe soils of this region.

This study presents data on the mammal fauna including Carnivora (5 families, 12 genera, and 17 species), Cetacea (2 families, 3 genera, and 3 species), and Artiodactyla (3 families, 8 genera, and 3 species). A total number of 28 species demonstarted an increase in the richness of these taxa over the past 50 years due to the introduction of one carnivorous species and two ungulate species. Among the latter, only the introduction of musk ox can be considered successful. In addition, sporadic occurrences of four species that were not part of the original fauna in Yakutia have been registered. The northern sea lion and bowhead whale can colonize marine regions of Yakutia, whereas the Asian badger can colonize its terrestrial regions if the current climate trend stays unchanged. The tiger is unlikely to survive the Yakutian conditions, due to both low temperatures and low density of the ungulates, which constitute the major part of its food supply. At present, the complete list of species that inhabit the terrestrial and marine areas of Yakutia includes 70 representatives of the Mammalia class. The major part of the mammalian fauna of the region consists of indigenous species, whereas the share of non-native species was only approximately 10%. The changes in the composition of the mammalian fauna over the last 50 years are connected with a better current knowledge of the regional fauna, introduction, and changes in the taxonomic rank of species and subspecies. Moreover, four new species were identified: Chiroptera (2), Insectivora (1), and Rodentia (1). Some clarifications have been made to the taxonomic rank of species and subspecies belonging to the genera Ochotona, Urocitellus, and Alexandromys (Microtus). The use of genetic approach can clarify the taxonomic rank of a number of species. More complete and precise data on the composition of the faunistic list, geographic ranges of these species can be obtained by covering the territorial gaps in the previous studies and additional research on understudied taxa, in particular chiropterans and marine mammals.

A short review of research on multiscale modeling of the fracture processes of heterogeneous materials with submicrostructures applicable to Arctic and Subarctic environments is presented. The results of solving a number of model problems, both in terms of macroscopic strength and main crack growth, and describing the accumulation of microscopic defects and hierarchical fracture processes by the mechanisms of formation, growth, and fusion of secondary and microcracks, and microscopic pores are provided. Thus, for the fracture process of samples of porous concrete modified with oil palm fruit fibers to improve its consumer qualities, a simulation of crack growth was conducted, which showed a decrease in the crack resistance of the material with increasing fiber content. A three-point bend test was used to evaluate the bending strength and modulus of elasticity, and the compressive strength and modulus of elasticity were determined. An increase in the fiber content led to a decrease in the compressive strength and modulus of elasticity. The fracture surface analysis revealed the mechanism of crack propagation through the coalescence of micropores. The basis of the modeling was an experimentally substantiated criterion for concentrated fractures during crack formation based on percolation theory. Macroscopic finite-element and stochastic modeling of fractures during the bending of a beam made of wood have also been carried out. For wooden structures, the peculiarity is the anisotropic behavior of the material in the loading direction. The structure of the Bilinga tree timber at the mesoscopic and microscale levels was considered, and a hierarchy of the spatial and temporal scales of the fracture process was constructed. The crack growth rates at different scales were determined and compared with macroscopic FE simulations. Another task was to determine the dependence of the crack growth rate in the soil, such as regolith, under the influence of an ultrasonic impactor. Stochastic modeling of the crack growth in the array of micropores revealed the crack growth rate dependence on the ultrasonic transmitter beater parameters and pulse amplitude.

The article presents the results of an experimental study of the water content effect on the elastic properties of a limestone specimen (Young’s modulus and Poisson’s ratio) during drying after its partial saturation. We first constructed the diagrams of water saturation and water loss, then on their basis we selected the partial saturation mode of the specimen. The specimen was subjected to uniaxial compression in the range of small reversible deformations. We chose the loading range of the specimen to exclude the formation and accumulation of microstructural changes (damages) in the material. The tests were carried out at certain intervals during the natural drying of the specimen. The values of the elastic modulus and the Poisson’s ratio were calculated based on the stress-strain diagrams in accordance with the standard STO 05282612-001-2013 adopted at the Chersky Mining Institute of the North SB RAS. The analysis of the test results revealed the features of the mechanical behavior of the limestone specimen, which indicate a disproportionate and even non-monotonic dependence of the elastic properties on the water content. We propose a hypothesis that allows us to explain the detected effects qualitatively.