Home – Home – Jornals – Journal of Mining Sciences 2025 number 3

Using 3D numerical modeling, we consider the formation of the postcollisional granitoids of the Kara orogen in Northern Taimyr 280–250 Ma under the conditions of elevated heat flow due to the orogen’s breakup, prior to the magmatic activity of the Siberian mantle plume. The initial geometry of the model area, boundary conditions and physical properties of the crust and mantle were set to be close to the structure of the Earth crust in the junction zone of the Kara, Central Taimyr and Siberian blocks. The model shows that in the granite-gneiss – andesite-basalt layer of middle crust widespread melting takes place, and at the base of the crust – a 1–2 km thick zone of melting of the granulite layer is formed with the possible participation a mantle component. The magma ascent rate and the formation of groups of adjacent granitoid plutons depend on the value of the elevated mantle heat flow and the rheology of the melting protolith rocks. The model describes the conditions for intrusion of magma and formation of plutons 10–20 km in diameter at depths 5–8 km in unmetamorphosed rocks. 3D modeling shows the mechanism of periodic magma intrusion pulses at the postcollisional stage during 30–40 Myr. The proposed formation mechanism for the plutons allows to reproduce their shape and emplacement periodicity comparable to their actual geological position and age of the postcollisional granitoids of the Kara orogen. We compare the results of modeling in 2D and 3D configuration with identical model parameters and physical properties of the rocks. We conclude that 3D modeling is a more realistic and accurate means of description of the respective magmatic processes compared to the 2D one.

Small bodies of restitic ultramafic rocks composed of dunite and harzburgite and enclosed to gneisses of the Olkhon composite terrane (West Baikal Area) are described. P-T parameters of metamorphism of the ultramafic rocks correspond to metamorphic conditions of the embedding gneisses and amphibolite. Peculiar Al-rich ultramafic rocks, composed of forsterite, enstatite and Cr-free spinel are found in restite dunite and harzburgite. They contain high concentration of Al₂O₃ (up to 23 wt.%) and MgO (25-37 wt.%), low silica (30-42 wt.% SiO₂) and very low CaO (less than 2 wt.%). We regard these rocks as products of syn-metamorphic high-temperature metasomatism (Max T=730-790°С) of the dunite and harzburgite. Comparison of the restitic and high-Al ultramafic rocks shows that in metasomatic process took part elements usually regarded low mobile - Al, Ti, V, Zr, REE, (input) и Mg, Si, Cr, Ni (output). There are no possible magmatic source of metasomatic fluids. We suppose that metamorphic felsic gneiss were the source of fluids in high-temperature metamorphic conditions. The impact of metasomatizing fluids on small fragments of aluminosilicate rocks in ultramafic rocks led to an even more significant enrichment of them with alumina (up to 50 wt.% Al₂O₃) and occurrence of specific mineral associations containing corundum and sapphirine.

The Late Mesozoic – Cenozoic intraplate volcanic province of Central and Asia unites a number of spatially isolated volcanic regions. Three periods of activity are distinguished in the history of its development. The initial period (between ~145 and 100 million years ago) was characterized by a regional extension and riftogenic magmatism. The middle period (between 100 and 30 million years) was distinguished by a subplatform tectonic regime and an areal type of volcanism. The late period (the last 30 million years) is distinguished as a period of volcanic plateau.

The magmatism of the province is determined primarily by alkaline basic rocks.. During the rift period, trachybasalts and trachyandesites were formed, the geochemical feature of which was high REE contents with low Nb and Ta contents. During the period of areal volcanism, trachybasalts and alkaline basaltoids with OIB characteristics became predominant.

The trends in variations of trace elements and the isotopic composition of Sr, Nd, Pb in mafic rocks of different ages in the province were determined and the compositions of their magmatism sources were estimated. It was shown that at all stages of the province development, one of the components of the magma source remained constant and was close to the asthenospheric mantle of the EMORB type. During the rift period, subduction-metasomatized mantle also participated in magmatism. During the period of areal volcanism, the metasomatized mantle was gradually removed from the composition of melt sources. Since that time, the magmatism of the province has been determined by the interaction of asthenospheric, plume (OIB-type) and depleted lithospheric mantles.

The formation of the province is associated with the emergence of a hot mantle field at the base of the East Asian lithosphere. Its origin is consistent with the activation of deep geodynamic processes at the beginning of the Late Mesozoic, primarily with the activity of the Pacific superplume.

The article presents the results of an analysis of data obtained on the Yamm–Torzhok regional profile, which crosses the Ilmen anomaly of electrical conductivity along its main axis. These works continue the long-term study of the structure of the Precambrian basement complexes of the western part of the East European Platform by the staff of the Department of Geophysics of the Faculty of Geology of Moscow State University and GEMRC IPE RAS. Based on the obtained data, together with the analysis of potential fields, a deep geoelectric model was constructed, and a model of the sedimentary cover structure was presented separately.

A method for processing a set of hyperspectral data in order to form a representative system of features is proposed, and object classification is carried out using 7 different systems of features in narrow spectral intervals (30 nm) of the visible and near IR spectral regions based on measured spectral brightness coefficients (SBC). It is shown that it is advisable to use systems of three features for classification of 12 types of vegetation and camouflage coverings. At the same time, traditional vegetation indices often used for plant research provide insufficiently high accuracy of classification of objects of selected types. Simultaneous use of two difference indices is more effective in comparison with them. However, the best classification accuracy is provided by systems of three features, which are integrated values of the SBC in specially selected spectral ranges. Note that the classification accuracy is equal to or close to 100% in almost all cases when classifying objects into two classes.

In this paper, three methods of spectral matching of remote sensing images are presented, namely, pixelwise linear, pixelwise nonlinear, and generalized nonlinear methods. Pixelwise nonlinear and generalized nonlinear methods are implemented as neural networks. The methods are compared using the Landsat-8 and Sentinel-2 images from the IEEE Data Fusion Contest 2021 dataset. According to the experimental results, the generalized nonlinear method of spectral matching of remote sensing images demonstrates the best matching quality.

Automated methods for counting the number of sunflower seedlings and constructing weed maps based on ultra-high spatial resolution RGB images obtained using an unmanned aerial vehicle are proposed. We propose automated methods for counting the number of sunflower seedlings and constructing weed vegetation maps from RGB images of ultra-high spatial resolution obtained by an unmanned aerial vehicle. The methods are based on the use of convolutional neural networks DeepLabv3+, ResNet-101, and YOLOv8. The results of experimental studies show that the accuracy of estimating the number of sunflower seedlings at early stages is 96% on the average.

The algorithm proposed by the author earlier for searching for small objects against a background of an inhomogeneous random texture has been modified. The modification allows one to work in parallel with multiple image segmentation. A weight is assigned to each segmentation, which is searched for by means of training based on the error backpropagation method. In the implemented process, five weights are determined by a set of a thousand of photographs of clouds measuring 1200×1200 pixels, on which model objects are applied - circles with a radius of two pixels. Initially, all weights are the same and are equal to 0.2. After learning, the maximum and minimum weights turn out to be 0.404 and 0.116. Graphs showing changes in weights indicate that the learning procedure converges. According to the results of the computational experiment, the modification turns out to be more effective than the original algorithm: the number of errors of the first and second kinds decreases by 1.23 and 1.8 times.

This paper suggests a method for reconstruction of optical satellite images using a neural network conditioned on co-registered synthetic aperture radar data. The solution is based on existing neural networks for image reconstruction - DiffCR and Palette, with a modified CBAM block for spatial-channel attention and a modified loss function. The experimental studies conducted show better quantitative and qualitative results in comparison with the baseline models.

A mathematical model of the characteristic of image displacement transformation into the measuring signal of the device for local vertical construction (DLVC) designed using a panoramic annular lens (PAL) and a focal plane array is considered. The deviation of the Earth's image center from the center of the annular image of space is calculated using the two-point centroid algorithm. A description of the laboratory setup for studying the DLVC transformation characteristic and experimental results are given.

The review article presents the results of an analysis of the most important feature of using special self-referential rotation units, which makes it possible to implement a calibration procedure for unique angular encoders included in high-precision angle measuring setups without using external flat angle standards.

Providing efficient operation and increasing the reliability of proton exchange membrane fuel cells (PEMFCs) require new tools for real time monitoring of their technical condition that have small-amplitude disturbances of the current operating mode. Currently, one of the most informative small disturbance methods for studying PEMFCs is impedance spectroscopy. The use of the wavelet analysis and broadband probing signals can significantly reduce the analysis time and, as a result, increase the efficiency of making diagnostic decisions. However, the problem of a significant loss of accuracy in assessing high-frequency components of the impedance has been identified. Within the framework of this work, it has been determined that the reason for this is a significant contribution of high-frequency spectral components with a low signal-to-noise ratio, reaching 4 dB. A technique for threshold signal processing based on the wavelet transform is proposed, which makes it possible to increase the accuracy of assessing the amplitude-frequency characteristics of the impedance up to 0.3% in the frequency range of 0.1-400 Hz without increasing the signal-to-noise ratio. The proposed tools of high-precision assessment of impedance characteristics based on the wavelet analysis of broadband signals will find applications both in research laboratories and in real operating power plants based on PEMFCs.

The front-end is a section of the synchrotron radiation (SR) beamline intended to interface the vacuum, radiation, and optical conditions of the SR source with those of the experimental stations. This work presents thermal analyses of key front-end components developed for undulator beamlines 1-1 and 1-2 of the Siberian Circular Photon Source (SKIF). The expected output power of the SR beam from a linear undulator is 7.1 kW. The finite element method implemented in the COMSOL® Multiphysics 6.2 software package, along with the method of the non-uniform power density distribution, is used for simulations. The paper reports the development of front-end components and 3D modeling results of temperature fields and mechanical stresses under continuous thermal loading in ultra-high vacuum conditions. Calculations are carried out for the following components: fixed mask, movable photon shutter, adjustable mask, radiation shutter, diamond vacuum windows, thermal filters, and SR beam monitors. The obtained results demonstrate that the designed cooling systems for the front-end elements efficiently dissipate the incoming thermal power of the synchrotron beam and ensure their reliable operation.

For a high-resolution spectral analysis of a fiber Bragg grating (FBG), the use of a new type of a tunable highly coherent laser, i.e., a fiber laser with vibration-induced sweeping, is demonstrated for the first time, in which wavelength tuning in the 2-nm range is induced by vibration of a part of the laser cavity. It is demonstrated that the use of the fiber laser makes it possible both to simplify the signal detection and to increase the accuracy of measuring the FBG spectra by an order of magnitude compared to schemes where pulsed self-sweeping lasers are used, due to averaging the signal over a larger number of points. The measurements show that the proposed technique can be used to resolve structures with a spectral width of about 64 MHz (~ 0.5 pm).

The paper describes the operation of a device for interrogating fiber sensors based on a Fabry-Perot interferometer (FPI) with a frame update rate of up to 70 kHz. The high performance is achieved due to the combination of a passive optical scheme based on a multichannel arrayed waveguide grating (AWG) and a phase algorithm for data processing. The possibility of high-rate interrogation of the sensor with accuracy of ~ 1% (~50 pm) of the measurement range is experimentally demonstrated.

A method compatible with the growth process has been proposed for processing reflectograms recorded in situ by a laser reflectometer during the growth of III-nitride layers by ammonia molecular beam epitaxy. This method includes data filtering based on the fast Fourier transform. The cause of an additional high-frequency signal appearing and interfering with the registration of informative interference oscillations of reflected light intensity has been established as the oscillation of the holder with the sample installed on it during growth rotation. Sample rotation is a necessary technological technique in molecular beam epitaxy growth, ensuring increased uniformity of epitaxial film parameters. A comparison of the thickness values of individual III-nitride layers, as determined by the processing of reflectograms using software, with values determined by scanning electron microscopy demonstrates good agreement between the two methods. Software has been developed that automatically filters out high-frequency signals and determines the growth rate of individual III-nitride layers grown by ammonia molecular beam epitaxy.

For metals, soil and rocks, a creep model non-associated with the Tresca and Mohr-Coulomb yield surfaces is discussed. The constitutive laws for creep in the model contain angles of internal friction and dilatancy. The authors propose a procedure for finding angles of internal friction and dilatancy using creep curves obtained from testing cylindrical samples. Determination of the time of failure at different irreversible strain rates and different initial stress levels uses the deformation-based and energy-based failure criteria applicable to both uniform and non-uniform stress states under long-term loading.

The analysis of dynamic events in the earth’s crust should take into account internal mechanical losses (energy dissipation) in rocks. Such dynamic events often have a frequency under 1 Hz. Internal mechanical losses are estimated in terms of the dissipation factor Q ^-1. Rayleigh damping represents the dissipation factor with respect to the direct and inverse dependence on frequency. The authors performed three-point bending tests of rock samples of different types and genesis. The dissipation factors are calculated for various frequencies of deformation. The empirical dependences of the dissipation factor on the frequency in a range of 0.003-0.100 Hz are approximated by Rayleigh damping. The coefficients of variation and determination are calculated to define conformity between the experiment and model data, the conclusion on the good agreement with the Rayleigh model is made, and the causes of differences between experimental and theoretical results are listed.

Thermal environment in vertical mine shafts has a significant influence on the shaft support and reinforcement, and on the safety of the while hoisting facility. Fluctuation of air flow temperature causes thermal deformation of structural elements in the shafts. Subzero temperature air enters mine shafts in the winter season because of deficient heating of air supply shafts and as a result of air flow reversal in ventilation shafts. As a consequence, tubing support in the shafts experiences cooling, the tubing joints open, and water inflow in the shaft goes over and above a guideline value, which can initiate an accident. The authors analyze the impact of subzero temperatures on the opening of tubing joints after change in the stress-strain behavior of the tubing ring-concrete lining-rock mass system. The developed and implemented numerical model of the mentioned geotechnical system determines patterns of temperatures and deformations in tubing rings in the periods of exposure to cold.

Mathematical modeling investigates the influence of an underpump tubing string on the longitudinal vibration intensity in the oilwell tubing and pumping unit assembly during operation of an electric submersible pump (ESP). The use of the underpump tubing strings with a length of ¼ wavelength with a dominant frequency of longitudinal vibrations of ESP reduces the vibration rate at this frequency by 2-3 times, and the diameter of the underpump tubing string is of no importance. Such underpump tubing strings in producing oil wells can help improve reliability and service life of ESP. When an underpump tubing string is set on the well bottom and pressed to the casing string along a spiral line, the longitudinal vibrations of the underpump tubing string transform into variable side stresses which influence the casing string and the reservoir rocks in the bottomhole formation zone, while no increase in the longitudinal vibration rate takes place in the pumping unit. The working ESP with the underpump tubing string rest on the well bottom conditions continuous vibration effects on a pay zone in the course of the well operation, which improves permeability of rocks in the bottomhole formation zone.

The seismic observations of dumps at the Mikhailovsky GOK open pit mine are carried out during mass blasting. The curves of the acceleration amplitude and velocity of vibrations in a blast-induced seismic wave and the reduced distance are plotted. The dynamic stability of the overburden dumps is estimated. It is shown that at certain reduced distances, multiple seismic effects of mass blasting can lead to the loss of the dynamic stability of the dumps. The results are applicable in mass blasting design and in location and parametrization of overburden dumps.

Support design in underground mining and tunneling excavations is dependent on the geological and geotechnical behavior of rock mass. The rock mass rating (RMR) and Q-System are the key parameters to design support system. The existing support system in tunneling projects along Himalayas were studied, and it was observed that the support was lighter in some cases and heavier in others. Based on the real time data obtained from active tunneling projects and geologic conditions along Himalayas, the modified support criteria (RMR₁₉) using back calculations and incorporating stress factor in RMR and Q have been applied in this study. The stress reduction factor of the Q-system was also studied. The existing and modified RMR and Q are statistically correlated with a significant R² value.

The article presents a theoretical substantiation of a dynamic adaptation process to adjust drilling and blasting patterns to structurally complex deposits and open pit mining using the integration of zoning theory and blast impulse theory. The key stages of approaches to drilling and blasting pattern designing are discussed. Emphasis is laid on the theory of rock fracture zoning with description of the zones of deformation, fracturing and seismic effect depending on the blast impulse. The calculation formulas are proposed to determine the blast impulse, radii of fracture zones and energy balance to ensure efficient rock fragmentation and minimization of adverse effects. It is critical to introduce artificial intelligence systems capable to analyze geological data in real time. The principles of creation of the intelligence control systems for drilling and blasting adaptable to varying geological conditions are developed. This can enhance safety and efficiency of drilling and blasting at mines operating at structurally complex deposits in Russia.

It is most effective to fracture very hard rocks by impact. On the other hand, application of the dynamic rock fracture method needs optimal parameters selected using modern techniques of estimation of rock fracture resistance dependent on the properties of rocks. The features of dynamic loading of an operating tool are discussed, and the classification of the dynamic rock testing methods is proposed. The rock crushability testing procedure is recommended. Resistance of rocks to fracture under dynamic loading is estimated, and the main estimation criterion is the volume yield of crushed material -7 mm in size. The strength characteristics of rocks from different testing methods were compared with the estimates of rock resistance to fracture by the selected criterion. The comparison shows a good agreement of the results, sufficient for engineering design.

The article discusses capacities and benefits of stripping with direct dumping within the mixed-type mining technologies for structurally complex deposits of solid minerals. The authors emphasize practicality of this technology in different geological and geotechnical conditions of mineral mining, and develop a procedure to determine a reasonable application range of the technology within the mixed-type mining systems. The resource-saving process flowsheets are proposed for dragline mining of centroclinal fold-type, water-encroached and steeply dipping bedded deposits. The most feasible ways of enhancing efficiency of overburden removal with direct dumping are discussed.

The mining drawing schedule is related to the safety, environment and ground pressure control of mine production, and is of great significance for controlling the economic indicators of mine operation in block cave mining. The mixed integer programming(MIP) method has been proved to be very effective in solving the medium- to long-term drawing sequence optimization problem in mines. The amount of ore, three kinds of the draw points priority order with diamond undercutting mode, and the logical relationship are considered as constraints based on the value model of ore-rock mixing. The maximizing net present value of the mining operation is used as objective function. Application and analysis of the model is solved using CPLEX, MATLAB, and YALMIP for a specific Chinese copper mine using 770 drawpoints over 7-year (28-quarter) periods.

The studies find out that permeability of loam is 51.6 times less than permeability of coal mass. Thus, this disperse sediment can be used to prevent spontaneous combustion of coal and carbonaceous rocks. The major insulating effect is provided by a loam layer with a thickness of 0.06-0.08 m, which reduces permeability of an insulated mass by 5 times. The increase in this loam layer thickness has a minor effect on the permeability. Water sprinkling yet more decreases the permeability of loam but drying-out initiates cracks in the insulating material and they give access for air to oxidizable coal. Recovery of the insulating effect after exposure to water requires ripping and compaction of loam.

The authors propose a model of activation of sphalerite flotation by lead ions using the mechanism of physisorption of a collecting agent. Flotation tests determined the recovery of zinc and the quality of the concentrate depending on the volume densities of lead and xanthate, the ratio of their mole concentrations and pH of the flotation system. The ratio of lead and xanthate mole concentrations of the increased sphalerite floatability, which is condition of casual activation of sphalerite, is found. The causes of suppression of sphalerite floatability at the increase in a certain concentration of the activating agent or xanthate are disclosed. On the basis of sphalerite floatability suppression, it is recommended how to enhance selectivity of separation of sulphides in the lead flotation circuit.

The review of literature and research findings exhibit current situation and the most challenging problems in theory of flocculation of mineral suspensions. With a view to enhancing efficiency of flocculants, it is advisable to have a science-based concept of selecting flocculants and their compositions, including functionally modified flocculants, with branched macro-molecules, with regard to laws of adsorption of flocculants at the surface of minerals. In the light of the revealed strength characteristics and laws of destruction of floccules, it is shown that for the further development of the theory, it is important to find interconnection of these parameters and fluid dynamics, and to study recombination of floccules. It is undoubtedly interesting to determine small concentrations of flocculants both for the analysis of formation of floccules and to disclose conditions of smart use of flocculants in the industry.

Because of the need to expand the range of promising Russian-manufacture reagents to replace import analogs, the authors study effect exerted by reagents from class of dithiocarbamates on the surface of sulfide minerals in composition of complex gold ore. New research methods are used to examine interaction of the test reagents with the gold-carrying minerals in flotation of complex ore. It is found that a new reagent of bis-piperazine dithiocarbamate is an efficient selective collector of mineral carriers of noble metals in flotation of complex gold ore. The test methods were UV spectroscopy, wetting angle measurement, scanning electron microscopy and laser scanning microscopy. Different adsorbed phases of the reagent on the polished section are determined and visualized. Selective attachment of the reagent at ore minerals can ensure their selective extraction in different concentrates in flotation of complex ore.

The article proposes technology of processing and modification of zeolite-bearing rocks from the Shivyrtui and Talan-Gozagor deposits with a view to producing high-quality adsorbents to recover rare alkali elements from hydromineral resources. The mineral composition of zeolite-bearing rocks is described, and their electromagnetic and electrostatic separation is reported. Using a model solution with cations of rare alkali elements, the sorption capacity of initial, concentrated and modified zeolite-bearing rocks from the Shivyrtui and Talan-Gozagor deposits is analyzed. Sorption of rare alkali elements is studied as function of a solution/sorbent ratio. The influence of cations in the model solution composition on the capacity of zeolite is examined. The water treatment tests show high results which ensure the required quality of effluents.

The article studies a new collector represented by a dithiazine-class complexing agent-1-carboxy-2-perhydro-(1,3,5-dithiazine)-5-il ethane (CPDE). The study of the physicochemical properties of the agent and its interaction with the mineral surfaces of galena and sphalerite used the methods of IR and UV spectroscopy, as well as measurements of wetting angle and free energy. It is found that the agent makes the surface of galena hydrophobic and the surface of sphalerite hydrophilic. The comparative flotation results indicate that the CPDE possesses higher selectivity as compared with the PBX agent and ensures selective separation of galena and sphalerite during flotation.

The Donbas region has accumulated hundreds of coal waste dumps, and not less than one third of them are self-heating. With a view to substantiating parameters of a system for temperature monitoring of self-heating coal waste dumps, the temperature field dynamics was analyzed using model fills. It is found that a fill of unoxidized waste rocks possesses more pronounced properties of a heat accumulator than a fill of oxidized waste rocks. The rate of average temperature variation and the temperature field nonuniformity of the model fills under influence of internal and/or external sources of heat emission are governed by both grain-size composition and thermal destruction of waste rocks. The features of temperature stratification of heated model fills are conditioned by their genetic structure and by spatial location of heat sources. The research findings are useful for determination of sampling times for heat meters, adjustment of their positions in subsurface zones of self-heating waste dumps, as well as for interpretation of temperature monitoring data of such man-made formations.

Floras of mountain territories are of interest due to species richness and а large number of endemic and rare species. However plant checklists published in the second half of the last century turned out to be unsuitable for usage due to modern taxonomic treatments, reidentification of herbarium specimens and results of additional field investigations. The purpose of this work was to compile an actual checklist of the flora of the Eastern Tannu-Ola Range, in which takes into account literary data, the current taxonomic and nomenclature points of view, the results of field researches of the author and other botanists, as well as reidentification of specimens, stored in the herbaria of the Central Siberian Botanical Garden SB RAS (NS, NSK). The actual checklist comprises 1028 species and subspecies of vascular plants which belong to 373 genera and 86 families. Of these, 119 species are listed for the Eastern Tannu-Ola Range for the first time. The 10 biggest families are Poaceae (124 species and subspecies), Asteraceae (121), Rosaceae (66), Fabaceae (62), Ranunculaceae (59), Cyperaceae (55), Caryophyllaceae (43), Brassicaceae (41), Lamiaceae (33) and Scrophulariaceae (31). All the ten largest families are the same as the ten largest families of the Boreal Region and neighbouring Western Tannu-Ola Range and Tsagan-Shibetu Range. However the flora of the Eastern Tannu-Ola Range belongs to Rosaceae-type (Central-European) by the first three largest families (Poaceae, Asteraceae, Rosaceae), while floras of Western Tannu-Ola and Tsagan-Shibetu Ranges belong to Fabaceae-type (Mediterranian-Mongolian) by the first three largest families (Asteraceae, Poaceae, Fabaceae), this points out on the position of the ranges of the Southern Tuva on the world watershed and the proximity of their floras to both North Asian and Central Asian floras. Twenty six species of the flora included into the Red Data Book of the Russian Federation and/or the Red Data Book of the Tyva Republic.

A review of the scientific literature devoted to the study of Astragalus glycyphyllos in various biological and chemical aspects are presented. Currently, studies of the native chemical complex of this type of Astragalus are relevant, with the establishment of the structure of its components, pharmacotherapeutic activity, useful properties and potential uses of A. glycyphyllos not only as a model object in biomedical research, but also, for the conditions of Russia, as analogues of pharmacopoeial types of Astragalus. The results obtained by scientists from different countries, as well as the experience of using A. glycyphyllos in folk medicine from different countries, serve as the basis for the multipurpose use of raw materials of this type of astragalus in pharmacy and medicine. Currently, studies of the recently established neuroprotective activity of extracts and individual compounds of the native A. glycyphyllos complex as potential drugs for the treatment of certain neurodegenerative diseases are becoming particularly relevant.

In a stable climate, the seasonal development of autochthonous plants is well synchronized with the local climate, which determines the stability of their fruiting. However, after the onset of global warming, the periodicity of crop formation began to change in many species, so there was a need to study the causes of this phenomenon. Using the example of Pinus sibirica Du Tour, an economically important nut-bearing species with uneven seed production over the years, the influence of short-term weather anomalies at the stage of cone formation and late spring frosts in the year of development of annual cones is considered. The research was carried out on the example of 180-200-year-old pine trees near the village in the south of Western Siberia. The harvest of mature cones was taken into account for the period 1990-2023. The number of cones laid was determined retrospectively by traces of fallen organs on the bark of shoots. At the same time, meteorological data for the same period obtained from the nearest weather station were analysed. It was found that the optimal conditions for cone setting are average daily temperatures no higher than +17.5 °C in the first ten days of August. The number of cones a depended on the spring weather in the year of growth and differentiation of annual cones and negatively correlated with the sum of active temperatures above +5 °C accumulated before the late spring frost. It has been suggested that the climatically determined continued increase in heat supply in the spring against the background of delayed frosts is fraught with an increase in the negative trend in the dynamics of seed production.

Saposhnikovia divaricata (Turcz.) Schischk. is endemic to Southeast Asia. Biologically active substances have been found in the roots of plants. Consequently, a massive and unregulated withdrawal of S. divaricata from plant communities has been noted, which may lead to a disruption in the balance of genes in cenopopulations of this species. The assessment of the genetic variability of natural populations and the development of S. divaricata cultivation technology is relevant. The optimal ISSR-PCR protocol for S. divaricata has been developed in this study: the most informative primers were selected, conditions for their specific amplification were selected, the polymorphism of ISSR markers in the natural population and plants of the 3-rd generation introducers were analyzed. We studied 16 samples from the natural population of Siberia (Republic of Buryatia) and 15 samples of introduced plants grown at the exposition “Rare and endangered species of plants of Siberia” of the Central Siberian Botanical Garden SB RAS (Novosibirsk). Total DNA was isolated by a modified CTAB method. Of the tested 17 ISSR primers, 4 informative ones for S. divaricata were selected, for which a comparative analysis of genetic variability was carried out. As a result, genetic distances, the level of polymorphism, intra-and inter-population variability were determined. We identified 114 PCR fragments ranging in length from 220 to 3000 bp, 108 of which were polymorphic (94.7 %). Using various statistical programs (TREECON 1.3b, GenALEx 6.51), it was found that the natural population of S. divaricata is characterized by high genetic variability: the Shannon indexis 0.48 ± 0.02, intrapopulation variability is 89 %. We have established that ISSR-PCR is a method for fast and accurate analysis of morphologically close populations of S. divaricata for the detection of genetic changes. For rapid screening, it is sufficient to use one of the four markers (HB12, HB14, 17899A, 17899B), which have shown high efficiency. As a result of the study, it was found that the genetic diversity of S. divaricata did not change under the conditions of introduction during the change of generations compared with the original natural population.

In botanical gardens, as points of primary intentional introduction, it is necessary to carefully study the tendency for naturalization of cultivated plants, and to conduct a preliminary assessment of their degree of invasiveness. The study analyzed chorological, biological and ecological peculiarities of introduced species of the medicinal plant collection of the Botanical Garden of the Ural Branch of the Russian Academy of Sciences (Yekaterinburg), both absent in natural communities in the territory of the Middle Urals and adventitious. The species in this collection showed relatively low ability to naturalize. Statistically significant relationship with the ability of species to naturalize has been established during cultivation in the subzone of the southern taiga. Such characteristics are: belonging to certain latitudinal (zonal) and longitudinal groups; the relationship of species to temperature and humidity; life form; taxonomic affiliation. Under the conditions of introduction, the impact on the ability to naturalize turned out to be statistically significant for such factors as timing of the beginning of spring regrowth, degree of winter hardiness of plants (assessed by the size of winter loss), the intensity of their seed and vegetative reproduction. The analysis carried out may be useful for forecasting and managing risks associated with the processes of naturalization and invasion of species into natural communities.

The article focuses on the diversity, ecology, and distribution of steppe on solonetz soils in the South-Minusinsk and North-Minusinsk basins. The steppes were classified into two classes: Agropyretea cristati and Festuco-Brometea. The first class, Agropyretea cristati, includes the following associations: Achnathero sibirici-Stipetum krylovii(variant Iris biglumis), Artemisio frigidae-Stipetum krylovii (variant Achnatherum splendens), Zygophyllo pinnati-Stipetum krylovii , and Allio ramosi-Stipetum krylovii(variant Leymus ramosus). The second class, Festuco-Brometea, is represented by the association Artemisio - Caricetum (variant Plantago salsa). Two ecological series of steppes were identified, with their diversity correlating with the soil’s richness-salinization gradient. The first series begins with the Achnathero sibirici-Stipetum krylovii association and its halophytic variant Iris biglumis . This is followed by the Artemisio glaucae-Caricetum pediformis association (variant Plantago salsa ) and concludes with communities on solonetz soils represented by the Galatello biflorae-Puccinellietum tenuissimae association. The second series starts with the Zygophyllo pinnati-Stipetum krylovii association, transitioning into the Allio ramosi-Stipetum krylovii and Artemisio frigidae-Stipetum krylovii associations, which are replaced by their halophytic variants: Leymus ramosus and Achnatherum splendens. This series ends with the more humid Artemisio glaucae-Caricetum pediformis association. The Zygophyllo pinnati-Stipetum krylovii steppes are found in the South-Minusinsk basin, where they form complexes with communities on solonetz soils, as well as with the Allio ramosi-Stipetum krylovii and Artemisio frigidae-Stipetum krylovii steppes. Halophytic variants of dry steppes (variants: Leymus ramosus and Achnatherum splendens) are observed in isolated small areas of the basin. The Artemisio glaucae-Caricetum pediformis association (variant Plantago salsa) is common in the North-Minusinsk basin, where it forms combinations with the Achnathero sibirici-Stipetum krylovii steppes in the landscape. Steppes on solonetz soils do not form large continuous areas in the South-Minusinsk and North-Minusinsk basins. Their distribution is closely associated with depressions around salt lakes, where the vegetation has been significantly impacted by heavy recreational use. As a result, these steppe communities are highly disturbed.

The paper presents the data on syntaxonomical diversity of forest vegetation of the «ribbon» forests of the Ob-Irtysh watershed. The dataset of 87 original and 152 previously published relevés was analyzed. To segregate the types of communities the TWINSPAN and the manual sorting in the software package IBIS 7.2 were applied. The ordination of syntaxa based on plants indicator values was conducted. The prevalent role of soil moisture in the differentiation of forest communities was shown. Forest vegetation is represented by 6 variants, 3 subassociations, 11 associations, 4 alliances and 4 orders from 4 classes. The class Koelerio glaucae-Pinetea sylvestris includes 3 associations and represents psammophytic pine forests with sparse herb layer, which is dominated by steppe and meadow-steppe plants. The group of most xerophytic communities with the predominance of psammophytes was described as a new association (Table 1). Ass. Stipo borysthenicae-Pinetum sylvestris Chupina et Korolyuk ass. nov. (Table 2, rel. 1-22), holotypus - Table 2, rel. 13 (field no. 96-023): Republic of Kazakhstan, Abayskaya Oblast, Beskaragajskiy district, 4 km north of the village Kanonerka, 12.06.1996, author - A.Yu. Korolyuk. D. s.: Alyssum tortuosum, Astragalus altaicus, Cleistogenes squarrosa, Eremogone biebersteinii, Erysimum canescens, Helichrysum arenarium, Jurinea schischkiniana, Kochia laniflora, Scorzonera ensifolia, Silene borysthenica, Stipa borysthenica, Syrenia siliculosa. Pine forests of the association are common in the southern parts of the “ribbon” forests in the steppe zone (Fig. 3). The communities occupy the gentle slopes as well as the tops of sand dunes. The density of the pine forest stand canopy varies widely and depends on the anthropogenic disturbance intensity. The facultative and obligate psammophytes predominate in the herb layer. The dominants are Carex supina , C. ericetorum , and Koeleria glauca. The class Vaccinio-Piceetea unites mesophytic pine forests with a developed moss-lichen layer. They relate to well-drained habitats with acidic soils. The class includes 5 associations that are widespread in the Burlinskiy pine forest and we had occured the class communities in other “ribbon” forests as well. Mesophytic pine forests with rich herb layer of the class Brachypodio pinnati-Betuletea pendulae include two associations, which were developed on the relatively rich soils. The swamped forest communities belong to the class Alnetea glutinosae. The both classes so far are pointed out for the Burlinskiy pine forest only.