Home – Home – Jornals – Numerical Analysis and Applications 2020 number 3

Unique magnesian-aluminous ultrabasic sapphirine-spinel and garnet gedritites of the Aulandzha block were studied. The deepest part of the Archean Stage of the Omolon massif is exposed in this district. The gedritites differ strongly in petrochemistry and geochemistry from other metaultramafites of this block. The difference is in their enrichment in alumina, zirconium, barium, rubidium, hafnium, and uranium and depletion in calcium and heavy rare-earth elements. The oxidizing potential in the sapphirine-spinel assemblage, estimated by physicochemical modeling using the Selector program complex, showed high oxygen fugacity in these rocks, close to the value of the magnetite-hematite buffer, which was never observed in ancient granulite complexes. The above petro- and geochemical features of the gedritites of the Aulandzha block, having an isotopic age of 1.9 Ga, are explained by the fact that these rocks are probably the crust of weathering of the enclosing metaultramafites. If this hypothesis is true, then the above rocks may indicate that the oxygen potential on the Earth’s surface corresponded to the magnetite-hematite buffer as early as the Paleoproterozoic.

We report the chemical and isotopic compositions of volcanic rocks of the Akhtang and Kostina mountain massifs in the Sredinny Range, Kamchatka. The analyzed rocks are similar in composition to the earlier studied volcanics on the eastern flank of the southern part of the Sredinny Range. Results of K-Ar isotope dating reveal three stages of volcanic activity in the two massifs. These stages are divided by long (1.4 and 2.4 Ma) periods of quiescence. In the Akhtang massif, the eruptive activity was at 4.9-4.0, 1.9-1.7, and 0.3-0.2 Ma, and in the Kostina massif, at ~8.0, 5.6-4.9, and ~3.5 Ma. Two early stages of both massifs are characterized by the eruption of island arc type rocks, and the late stage, by the eruption of rocks of hybrid geochemical type. The Mio-Pliocene (N₁-N₂¹) rocks of the Mt. Kostina massif are similar in geochemical features to the early Pliocene (N₂¹) rocks of the Akhtang massif, and the late Pliocene (N₂²) lavas of the former massif are similar to the middle Quaternary (Q₂) rocks of the superimposed monogenetic volcanism zone of the latter massif. For the Akhtang massif it has been first discovered that the volcanic reactivation after the long quiescence periods was accompanied by a change in the composition of rocks and in the type of eruptive activity (from the eruption of plateau-effusive rocks to the formation of stratovolcano and monogenetic volcanism zones). The obtained data on the age and composition of rocks as well as some morphological features of the studied massifs suggest that the plateau-effusive rocks of the Sredinny Range might be related to central-type eruptions.

Supplementary materials

Ground Penetrating Radar (GPR) surveys in the area between Sherashevo and Inkino villages provide insights into the structure of the Delta Fault and allow estimating the amount of vertical slip caused by the M = 7.5 Tsagan earthquake of 12 January 1862. The surveys with shielded AB-90 and AB 250-M antennas of an OKO-2 georadar along five profiles spaced at 25 m reveal normal slip from 2.6 to 4.5 m in different segments of the main seismogenic fault. The surface rupture caused by the 1862 event is traceable in interpreted radar images together with subsidiary faults; some possibly resulted from the 1959 Middle Baikal earthquake (M = 6.8). The GPR data are used to construct a 3D model of the area, which illustrates the evolution of the Delta Fault scarp since the Tsagan earthquake. Much of surface rupture during the Tsagan event is due to gravity sliding, judging by the amount of displacement estimated from GPR, structural, and field data of different years. Comprehensive understanding of the displacement pattern along the seismogenic fault requires further study extended to other segments of the fault zone.

Variations in the magnetic and geochemical properties of the sediments of Lake Bol’shoe Yarovoe (Altai Territory) were studied. The data were derived from five core columns (up to 4.5 m long) covering a time interval of more than 8000 years. In addition, coercive spectra were obtained for 792 samples taken every 2 cm. Coercive spectra were then used to identify soft magnetic (10-15 mT) and hard magnetic (35-50 mT) components. The soft magnetic component is detrital, and the hard magnetic component is biogenic, which is confirmed by microscopic studies. Moreover, the samples contain micrometeorite particles. Variations in geochemical properties allow reconstruction of the environmental history of the lake. Sediments in the lower part of the section vary both in the content of ferrimagnetic components and in geochemical properties, which indicates a sharp environmental change between ~6100 and ~7600 years ago. Alternation of warm (dry) and cool (humid) periods is observed higher in the section, between ~4100 and ~6100 years ago. It has been found that the variations in the magnetic components are consistent with the environmental changes and can be used for the historical reconstruction.

We present results of a study of carbonate coatings formed at the lower surfaces of pebble inclusions in Holocene-Upper Pleistocene deposits of the Irkutsk-Cheremkhovo plain. The coating resulted from the leaching of carbonates from the overlying deposits during pedogenesis. They are composed of pure and magnesian calcite with minor inclusions of quartz and feldspars. The coatings form morphologically and compositionally different microlayers, which reflect a successive change in the pedogenesis conditions during their formation. The stable-isotope composition is as follows: δ13С is -6.80 to -2.05 ‰, and δ18О is -16.33 to -10.15 ‰. It reflects the precipitation of carbonates during the degassing of soil solutions in the course of periodic freezing-thawing processes, dynamic increase and decrease in the biological activity of soils, and alternating moistening of soil with meltwater and rain water in spring and its subsequent freezing, which could occur in the region in spring and autumn. A joint analysis of the carbon isotope composition of the organic matter of soils and carbonate coatings shows that the latter formed in the phytocoenosis environment with predominant C3 vegetation. The difference in the morphology and occurrence of the coatings permit them to be divided into three groups. The coatings of the first group formed in the Middle Holocene (3.6-3.3 cal. ka BP), and the pendants of the second and third groups, in the second half of MIS-3 (24.1-23.3 and ~34-35 cal. ka BP, respectively). The paleoecologic conditions reconstructed for the established stages of carbonate coating formation are in satisfactory correlation with the general course of climatic fluctuations in the region and in the Northern Hemisphere as a whole. They reflect the influence of temperature and humidity fluctuations on the dynamics of pedogenesis processes. Comparison of the age of the coatings with the age of recent and buried soils shows that the pedogenic carbonate coatings in the Upper Angara soils are a relict feature of the previous epochs of pedogenesis (MIS 3) and the first stages of recent soil formation, which began, most likely, in the Middle Holocene. Based on analysis of the rates of coating formation and comparison of the isotope composition of the coatings of different age groups, we assume that the climate in the Karga (MIS 3) megainterstadial was more humid than that in the Middle Holocene, with the temperatures of pedogenesis being the same. Both in the Middle Holocene and in the Karga epoch, the regional soils received little heat and were seasonally frozen for a long time.

Well logs and core analyses of Berriasian-Aptian petroliferous sediments from the western Gydan Peninsula are used to model their biofacies and lithofacies and to reconstruct the respective sequence stratigraphy. The sedimentological and palynological data, along with logging results, provide constraints on the history of transgressive and regressive events and make a basis for paleogeographic reconstructions for the Lower Cretaceous deposition of reservoir sand beds.

The gradual transition of the Bazhenov Formation top into the overlying deposits makes it difficult to establish its upper boundary. The problem is aggravated by the lack of core material when the formation is recognized according to the results of geophysical well studies. A comprehensive analysis of geochemical and lithological data and the results of geophysical well surveys enabled us not only to determine the specific structure of the transitional zone from the Bazhenov Formation top to the rocks of the sub-Achimov member but also to propose the criteria for delineating the upper boundary in the central regions of the West Siberian sedimentary basin within the Khentei hemianteclise, the South Nadym megamonoclise, and the Mansi syneclise. Four members are distinguished in the transitional zone of the studied well sections (from bottom to top), which differ in lithological, geochemical and geophysical characteristics: (I) the “coccolithic” upper part of the Bazhenov Formation; (II) transitional member from the upper part of the Bazhenov Formation to the bottom of the sub-Achimov member; (III) transitional member from the bottom of the sub-Achimov member to its lower part; and (IV) the lower part of the sub-Achimov member. Member II is virtually not distinguished within the Khentei hemianteclise and the South Nadym megamonoclise. Member III contains the boundary between zones with different redox conditions. In case member II is distinguished, the upper boundary of the Bazhenov Formation corresponds to its top. To recognize the Bazhenov Formation top, it is necessary to use the integrated-analysis results of the lithological and geochemical studies of the well core and logging data (gamma-ray logging, neutron gamma-ray logging and its variations, lateral logging, and induction logging) when focusing attention mainly on radioactivity.

Petroleum geochemical characteristics are a major parameter of hydrocarbon field development. The present study is an attempt to decipher the unusual Bangestan (Cretaceous age) oil distribution throughout the Ahvaz oil field, SW Iran, based on SARA test and GC-MS analysis of selected oil samples. The results indicated that all analyzed oils belong to the paraffinic group. Hydrocarbon indicators, such as tricyclic triterpane C₂₂/C₂₁ (high), C₂₄/C₂₃, and C₂₆/C₂₅ (low) and hopane C₃₁R/C₃₀ (high) ratios and C₂₅/C₂₆ ratio vs C₂₅/C₂₆ tet ratio, show that these oils sourced from carbonate-marl rocks. The high saturated/aromatic hydrocarbon ratio in these oil samples may be related to long migration or high maturity. The biomarker variation exhibits a marine environment for the source rocks deposition. The observed oil maturity trend is showing a good correlation with the prevailing geothermal gradient and possible basement faults and fractured system. The increasing oil maturity in the eastern part of the field may be related to a heat flow anomaly. It seems that the area around well C (the area of wells C, D, or E) can be considered a petrochemical separator of fluids for two sides of the field. Therefore, it can be concluded that the observed petrochemical pattern is a complicated response of several factors: the presence of a palaeohigh, basement-controlled faults, petroleum source rocks, fractured system, and geothermal gradient variation in this deep reservoir.

The paper considers the manifestation of electromagnetic (EM) signal over the conducting polarizable ground on the measuring lines located on the axis of the source and inside it (for the symmetric Schlumberger installation). The research is based on a numerical experiment. Calculations of the EM response from one-dimensional models were carried out. The polarizability is taken into account by the frequency-dependent resistivity, using the Cole-Cole model. We describe the results of a numerical experiment on calculation of the induction signal over a conductive polarizable medium on grounded 2- and 3-electrode measuring lines located in the axial and equatorial zones of the source. It is shown that the induced polarization and the polarization associated with galvanic and eddy current are manifested in different ways.

The solution to the problem of light scattering by spherical particles is presented, adapted for the interpretation of lidar signals for applied problems. The solution was obtained for typical wavelengths used in laser sensing 0.355, 0.532, 0.905, 0.940, 1.064, 1.55, 2.15, and 10.6 mm within the Mie scattering theory for water and ice. The inherent high-frequency oscillations in the backscattering direction are smoothed out by means of a moving average, which allows one to construct fast and efficient algorithms for particle size distributions observed in the atmosphere.

The interrelationships between the variations in CH₄, CO, CO₂, NO, NO₂, O₃, and SO₂ concentrations and the aerosol number density and such meteorological quantities as air temperature, atmospheric pressure, wind direction and speed, global solar radiation and ultraviolet radiation in the range 295-320 nm, relative humidity, and partial pressure of water vapor are studied. For that, we used data on monitoring the air composition (for the period 1993-2018) performed at the TOR-station of IAO SB RAS located in Tomsk.

CO₂ spatial and temporal variability in five Russian regions has been analyzed on the basis of OCO-2 satellite measurements (more than 300 days during 4.5 years, more than 50 000 measurements). The Orbiting Carbon Observatory-2 (OCO-2) allows measurements of CO₂ content with a high accuracy (0.25-0.5%) (for data with a quality flag “0”), a high horizontal resolution (1.29^{´ 2.25 км2), and a spatial coverage along paths of ~ 10 km. That makes it possible to analyze the spatial and temporal variations in CO₂ column-averaged dry-air mole fractions (XCO₂). XCO₂ OCO-2 data with quality flag “1” has lower measurement accuracy, but the number of such measurements is 5-10 times greater than that with quality flag “0”. XCO₂ satellite measurements with quality flag “0” in the vicinity of Moscow, Saint Petersburg, Yekaterinburg, Magnitogorsk, and Norilsk (circles with a radius of 100 km from the city centers) have been analyzed. Comparisons of the meaurements in different cities and regions show that XCO₂ datasets with a quality flag “0” are homogeneous, the amplitude of XCO₂ variations amounts to 5-6%, root mean square variations are less than 1%. The maximum values of XCO₂ spatial variations totals 2-4%, which differs significantly from the results of the analysis of OCO-2 XCO₂ data with quality flag “1”.}

The results of a large-scale investigation of carbon dioxide and methane distribution carried out in Western Siberia in 2018-2019 using a Picarro G4301 portable gas concentration analyzer are presented. The analysis of the obtained data enabled the spatial distribution of background concentrations of CO₂ and CH₄ to be retrieved with a high resolution. The revealed inhomogeneities in the CO₂ and CH₄ distribution is a result of both the effect of ecosystem features in different regions of West Siberia and the characteristics of their seasonal cycles.

The passive technique for crosswind velocity retrieval from a video series of incoherent images, developed in previous works, has been tested. The technique is based on the visualization of air-drifted turbulent air inhomogeneities which distort optical images recorded. The results of retrieval of the crosswind velocity by the technique suggested are compared with anemometer measurements at paths of up to 1 km in length.

The alignment technique and quality check of the large mirror of the Siberian lidar station (SLS) with the diameter of 2.2 m is considered. The results of computer simulation of the field aberrations of the large mirror are presented and the area of the coma-free region is determined. The spot diagram of the large SLS mirror is measured by estimating the image size of stars passing through the zenith are presented. The numerical simulation of the lidar signal using ray tracing in the optical CAD ZEMAX is carried out taking into account the influence of a real scattering circle of the receiving optical system. The shape of the experimentally registered and ray tracing simulated lidar signal is compared.

To validate the atmospheric general circulation models ECHAM5-wiso and ECHAM6-wiso with embedded water isotopic modules, the simulation with nudging to known fields of temperature, pressure, wind speed and direction obtained from retrospective climate analysis was performed. The simulation results were compared with data on the isotopic composition (dHDO and dH₂¹⁸O) of water vapor in atmospheric air near the surface obtained at two monitoring stations: in Labytnangi (66.660N, 66.409E) and in Igarka (67.453N, 86.535E). An unambiguous conclusion about the superiority of the newer model ECHAM6-wiso could not be made, because the simulation results with its use demonstrate a better agreement with the values observed in Igarka, while the model ECHAM5-wiso shows a better agreement with the values observed in Labytnangi. The simulation results can be used as an a priori ensemble for solving inverse problems of remote sensing of the atmosphere in Western Siberia.

The contradiction between the results of determining the phase velocities of sea waves from optical images of the sea surface and data of in situ measurements by an array of wave sensors is analyzed. The phase velocity estimates obtained from optical images well correspond to the theoretical values derived from the linear dispersion relation for gravitational waves. For in situ waveform measurements, the phase velocities exceed the theoretical values. It is shown that the excess is caused by the fact that when in situ measurements are made, the contribution to the phase spectrum is given by waves that come from different directions and have different projections of the phase velocity in the direction in which it is determined.

An increase of 50% in the amplitude of the photoacoustic signal generated when water vapor absorbs pulses of laser radiation at 266 nm with circular polarization, relative to the signal for radiation with linear polarization, is reported. The effect observed is associated with different dissociation efficiency of H₂O molecules as a result of one- and two-photon absorption of radiation with linear and circular polarization.

A universal function is suggested for calculation of the A-broadening coefficients γ of H₂S absorption lines (A = He, Ne, Ar, Kr, and Xe). Only one parameter of this function depends on the broadening gas atom, while other parameters are common for all atoms. This parameter determines the ratio γ(А)/γ(А') for A and A' atoms. Parameters of the function are determined in the fitting procedure from the coefficients g measured and calculated for ν₁, ν₂, and ν₃ vibrational bands of H₂S molecules. The coefficients γ calculated are statistically compared with measurements. With the exception of some data for the ν₁ and ν₃ bands, the calculated and measured γ are in a good agreement for all collisional partners A.

The potentials for and limitations to the use of intensity fluctuations of laser beams propagating through a turbulent atmosphere for generating random data when keying in confidential optical communication systems are analyzed. The technique is based on the reciprocity theorem for optical fields. Light propagation in a system of two transceivers directed at each other, the signals from which are distorted by an atmospheric channel, is numerically simulated. An experimental setup is created; the generation of random correlated signals in such a system is experimentally studied. A need for low-pass filtering of signals received is experimentally ascertained. The efficiency of this filtration is estimated. The dependences of the correlation coefficient on the geometrical parameters of the system and turbulent conditions along the propagation path are derived from the numerical simulation in a wide range of distances, aperture radii, and values of turbulence intensity. Theoretical results are shown to be in a good agreement with the results of laboratory experiments.

The retrieval efficiency is analyzed for atmospheric turbulence distorted images formed by single- and multi-aperture systems. Based on numerical simulation it is shown that the use of multi-aperture observation systems for computer correction of atmospheric distortions under anisoplanatism can significantly reduce the exposure time. In this case, the main distortions are well corrected when imaging for a short exposure time, which corresponds to the case of a “frozen” turbulent medium. Correction of residual small-scale distortions requires an-order-of-magnitude shorter time than in the case of long-exposure imaging with the use of common single-aperture observation systems.

In the traditional pure rotational Raman (PRR) technique, air temperature is retrieved from lidar signals with a temperature retrieval function (TRF). The TRF coefficients are determined using a reference temperature profile from a model of the atmosphere or radiosonde data. In this work, we study the stability of several TRFs in time, i.e., we investigate to what extent the TRF coefficients determined on one of the measurement campaign days can be used to retrieve temperature on other days. We also analyze the situation when the reference data are absent on one of the measurement days (for example, due to a radiosonde fall) and the TRF coefficients are determined from the reference data over the remaining days. The stability of five TRFs is studied on the example of nighttime temperature profiles that were obtained using the IMCES PRR lidar (Tomsk) on April 6, 7, and 8, 2015. The function which retrieves the temperature in the troposphere (3-9 km) with the least errors for the considered three-day period has been determined.

The results of the cloud liquid water path (LWP) “land-sea” gradient retrieval from ground-based measurements of downwelling microwave radiation near the coastline of the Gulf of Finland in Saint-Petersburg region are presented. The measurements were carried out with the RPG-HATPRO radiometer operating at the Faculty of Physics of Saint-Petersburg State University in the angular scanning mode. The inverse problem was solved by the linear regression method. Different statistical models of cloud cover were used for training the algorithm. The LWP gradient mean values were derived over the winter and summer periods of seven years of observations. The results have shown positive “land-sea” LWP gradient (higher values over land and lower over sea) during both summer and winter seasons. This fact is qualitatively consistent with available satellite data.

The results of experimental studies of the atmospheric boundary layer in the coastal zone of Lake Baikal using a coherent Doppler wind lidar and a temperature profiler are presented. Temporal-altitude distributions of the wind speed, temperature, and the Richardson number are derived. It is found that in the measurement site during all the experiment from August 6 to 23, 2018, day and night the thermal stratification was stable with formation of low-level jets. The temporal-altitude distributions of the Richardson number have layered structure. Layers with Richardson numbers higher than the critical value alternate with layers with the Richardson number lower than the critical value.

The results of experimental studies of the atmospheric boundary layer in the coastal zone of Lake Baikal using a coherent Doppler wind lidar and a temperature profiler are presented. Temporal-altitude distributions of the wind speed, temperature, and the Richardson number are derived. The parameters of atmospheric waves in a stably stratified boundary layer are determined. Variations in the dissipation rate of the kinetic energy of turbulence, the variance of the fluctuations of the radial velocity, and the outer turbulence scale during the low level jets and internal atmospheric waves in the stable boundary layer and their relation to variations in the Richardson number are analyzed.

Recommendations for the use of aerosol turbulent lidar for research in the atmospheric boundary layer are presented. The peculiarity of the turbulent lidar is that the sounding path angle should not exceed 10°. It is found that the optimal angle is 4°, at which it is possible to determine the structural constant of the refractive index in the range of altitudes from 100 m to 1 km. This range can be extended by 2 times if sounding at two or three angles to the horizon.

The relationship of the daily UV-B radiation with factors influencing it (total ozone content, cloudiness, and aerosol optical depth) is analyzed. For this purpose, a homogeneous series of UV-B radiation data obtained at the TOR-station of the IAO SB RAS from 2003 to 2016, as well as satellite data on TOC, AOT data from AERONET network, and the data on total cloud cover from the meteorological site of IMCES SB RAS were used. The regression equations of the daily UV-B radiation variations depending on the changes in total ozone content under different cloudiness and air transparency conditions have been derived.

The spatial near-field structure of optical wave scattered by a composite amplitude-phase diffraction mask with a ruling period on a wavelength scale is studied in numerical simulations by the finite element method. As applied to the displacement Talbot-nanolithography, such a combined binary mask is shown to provide multiple enhancement of the optical contrast of an integral "Talbot carpet" as compared to pure amplitude and phase masks. The physical causes of this effect are analyzed and the key role of Mie resonances excited inside the dielectric bars of the phase mask is ascertained. Meanwhile, the combined mask suggested ensures a high spatial resolution (up to a quarter of optical wavelength) and maximal optical contrast (up to 24 dB) of integral Talbot's self-images.

An ensemble of independent numerical solutions enables one to construct a hypersphere around the approximate solution that contains the true solution. The analysis is based on some geometry considerations, such as the triangle inequality and the measure concentration in the spaces of large dimensions. As a result, there appears the feasibility for non-intrusive postprocessing that provides the error estimation on the ensemble of solutions. The numerical tests for two-dimensional compressible Euler equations are provided that demonstrates properties of such postprocessing.

New h-, p- and hp-versions of the least-squares collocation method are proposed and implemented for solving the Dirichlet problem for the Poisson equation. The paper considers some examples of solving problems with singularities such as large gradients, high growth rate of solution derivatives with increasing the order of differentiation, discontinuity of the second-order derivatives at the angular points of the domain boundary, and the oscillating solution with different frequencies in the presence of an infinite discontinuity for derivatives of any order. The new versions of the method are based on a special selection of collocation points in the roots of the Chebyshev polynomials of the first kind. Basis functions are defined as a product of the Chebyshev polynomials. The behavior of the numerical solution on a sequence of grids and with an increase in the degree of the approximating polynomial has been analyzed using exact analytical solutions. The formulas for the continuation operation necessary for the transition from a coarse mesh to a finer one on a multi-grid complex in the Fedorenko method have been obtained.

Indicator values are becoming an increasingly popular tool in basic and applied botanical research: about 55 author’s phytoindication systems are known, including about 200 optimal and range scales for various environmental factors. This paper describes seven methods for calculating the phytoindication optimum of taxonomical list: structural methods and averaging methods with weighting by indicators of taxon’s participation (cover, frequency, activity) and the degree of ecological tolerance amplitude width. Optimum and interval indices of ecological consensus are proposed for a quantitative assessment of the level of ecological homogeneity of plant communities and floras. A critical comparison and assessment of the distinguishing ability of the described methods of environmental calculation and consensus indices was carried out in the environmental analysis module of the IBIS 7.2 botanical information system using vegetation data from Bashkiria and the Southern Urals at the level of phytocoenoses assigned to 4 communities and their coenofloras. The possible directions of further use of the results of indicator value analysis in phytocoenology and floristics are described.

Molecular genetic analysis widely used in various fields of science currently. Molecular ecology for environmental assessment is the basis of the modern methodological base. Different species and populations contain a large supply of genetic variation. This which plays a major role in the adaptation of species to certain environmental conditions. A significant part of this variation does not have a clear phenotypic expression and constitutes a hidden stock of genetic variation, which greatly complicates the study of the huge genetic potential of genera, species, and populations. More convenient markers for studying these issues are seed proteins and DNA, which are characterized by significant intraspecific polymorphism and independence from the external conditions of plant growth, and electrophoresis of storage seed proteins and all methods of PCR amplification of genomic DNA. This review shows the role of molecular genetic methods in solving traditional environmental problems related to taxonomy, phylogeny, evolution, the study of genetic variability and the identification of inbreeding depression in natural and artificially created populations of endemic, rare and endangered species, as well as their certification (by stroke - coding) and the creation of DNA banks.

The use of molecular genetic methods for the species identification of fungi and myxomycetes (DNA barcoding) showed that it is necessary to reconsider the views on the ecology and habitats of many species of spore organisms. Spores of basidiomycetes and myxomycetes can spread over considerable distances with the help of water, wind, and insects, which contributes to the settlement of various distant habitats, where only microenvironment and substrate act as limiting factors. The possibility of settling various “island” habitats, for example, such as large tree debris in the steppe regions or special microclimatic conditions on the bottoms of ravines and gullies in the forest-steppe, where the humidity is much higher than on the plain areas, allows spore organisms to expand their habitats and settle in uncharacteristic for them natural areas. Own research, analysis of the literature and data in GenBank showed that for spore-forming organisms, when studying the ecology and patterns of distribution, the question of their correct species identification arises. The article discusses examples of the influence of the hypothesis “Everything is everywhere, but the environment takes away” (EiE hypothesis) on the understanding of the ecology and ranges of some species of myxomycetes and basidiomycetes. For the first time, data are presented on the distribution and ecology of the nivicolous species of myxomycetes Lamproderma pseudomaculatum on the plain territory of Western Siberia. Using the myxomycetes Arcyria imperialis and A . stipata , as well as the fungi Disciseda hyalothrix and Pleurotus pulmonarius , the possibility of using DNA barcoding to study the species diversity of spore organisms, differentiate morphologically similar species, and correctly interpret their ranges and ecology is shown. For all of these species, rDNA sequences were studied; photographs were taken on a scanning electron microscope for myxomycetes.

Plant diversity, species richness patterns, and determinants for different growth forms and range sizes on the territory of Inner Asia have been studied. Main factors determining species diversity in Inner Asia are past climate changes and parameters of precipitation. Temperature of current climate had little effect on the species richness patterns. Precipitation seasonality, mean precipitation of winter and spring, diurnal range of temperature dominated the richness patterns of woody species, while climate velocity since the Last Glacial Maximum and Mid-Holocene, precipitation seasonality and mean temperature of summer dominated the richness patterns of herbaceous species. Increasing of aridity in the studied region can influence the distribution of species with narrow range in the future.

As studies have shown, individuals from well morphologically distinct groups often represent the same species and may even belong to one population in fish and lampreys from environments with unstable abiotic factors (Arctic, mountain, and desert regions). Phenotypic plasticity ensures broad variation ranges of morphological traits in unstable conditions, which require rapid transitions from one morphogenetic variant to another. The choice of a morphogenetic pathway can be influenced by the level of individual heterozygosity, changes in the copy numbers of certain DNA sequences, heteroplasmy, and the presence of several allelic variants in the genes that strongly affect the phenotype. A cyclic character is often observed for evolutionary processes driven by these mechanisms, and speciation usually does not take place in unstable environmental conditions. However, mobilization reserve accumulate in a species with a broad reaction norm, and particular morphogenetic pathways may be genetically fixed when its population finds its way into stable environmental conditions, facilitating fast allopatric speciation.

Studies of 35-year dynamics of the number of bird species of and 80-year observations of their arrival on the western macro-slope of the Barguzin Ridge have been carried out. A steady decrease in the total abundance of background species of birds after 1997-1998 was revealed. Shifts and cyclic changes in the time of arrival of birds were found. The 26 species (40.0 %) from the 65 species arrived statistically significantly earlier, 7 species (10.8 %) arrived later, and 32 species (49.2 %) had no statistically significant timing. Links have been established between the timing of the first registrations of migratory bird species and their local abundance and habitat distribution. Some mechanisms for forming the local bird’s population have been disclosed, including using redistribution of species breeding density between river valleys and habitats on a high profile.

A study of the long-term abundance of ground beetles of the genus Carabus over a thirty-year period made. The ratios of climatic factors that have a corrective effect on the level of their numbers are established. The level of precipitation, the duration of the frost-free period and the ground temperature on the soil surface are the most important meteorological parameters in the ground beetles life of genus Carabus. Air temperature effects through the duration of the biological summer, limited by the timing of the onset of spring and autumn indirectly. The gradation cycles of long-term series determined by intra-population and climatic processes are determined. It’s consists of short 2-4 years and long 7-10 summer periods. Within the framework of phase portraits, the mechanism of action of regulatory factors on the process of numbers long-term dynamics are considered. Stable and prodromal types of the number dynamics of long-term series were established. Fluctuations in the abundance of ground beetles of the genus Carabus did not go beyond the framework of the stationary process during the studied period.

High-detailed images acquired by means of unmanned aerial imaging allowed for description of certain type of thermokarst depression structural features. These depressions developed in yedoma deposits in southern part of typical tundra subzone in Lena Delta. Geomorphology and vegetation of the model depression were characterized by the combination of GIS-analysis and ground survey. Detailed mapping showed that the surface of the depression bottom consists of “baidjarakh” field covered by the complex vegetation of highly productive plant communities dominanted by grasses and graminoids. Comparison of satellite images and topographic maps from different years showed that depression appeared from the shallow thermokarst lake drained not later than 40 years ago. Depression terrain and vegetation are determined by its origin and the composition of surface geological substrate. Depression vegetation is quite contrast to zonal tundra by its structure and floristic composition. It contains few species which tend to be more typical for southern distribution. Such spots serve as feeding places for herbivorous animals and in the past could be an important part of the Pleistocene megafauna forage. Thermokarst events were typical for the ice-complex through the whole period of its formation, but might differ in intensity and area depending on climate conditions. Nowadays size and lifetime of thermokarst lakes depends on their position in terrain and thermoerosion intensity. In tundra landscape thermokarst plays an important role in creation of new habitats and plants and animals biodiversity support.

Based on geobotanical releve GPS coordinates of 7 altitudinal zone associations of Tuva forests and a set of rasters with climatic and topological parameter values, the potential areas of associations has been drawn using the MaxEnt software package. These technique allowed us to extrapolate fragmentary data on specific localities of plant communities to the territory that had not been studied in detail before. The data on the areas of altitudinal zonal associations of forests correspond to real distribution of forests. The analysis of potential areas of these forests has been carried out, the presence of three bioclimatic sectors in Tuva has been confirmed, and their borders have been clarified.

The assessment of the representativeness of the protected areas is necessary to optimize the national and regional protected area networks, as well as to improve the protection of rare and endemic species. In the Republic of Bashkortostan (RB), an analysis of the distribution of rare vascular plant species in need of protection was carried out on the basis of a synthesis of all sources of high-precision geo-referenced data, i. e. the data bases of herbarium specimens and geobotanical relevés. The result of these works was the creation of a graphic database - GIS-map “The rare and endangered species of vascular plants of the Republic of Bashkortostan.” This GIS-map includes three main vector layers: a point layer containing information about 4932 rare species localities, a layer “Protected areas borders” and a grid layer, with cells 6ʹ in latitude × 10ʹ in longitude (10.8 × 10.2 km). Based on these layers and standard procedures of the QGIS 3.4 program, an algorithm has been developed to analyze the patterns of distribution of rare species throughout the region, as well as to identify areas with a high diversity of these species and their covering by the existing nature protected area network. On an example of two grid map cells with a high diversity of rare species the approaches to the identification and delineation of further sites of nature protected areas were considered using space images and a digital elevation model. In order to estimate the protection level of the unique combinations of rare species, the distribution of all set of these species within the existing protected areas was assessed. This allowed to justify the creation of two new nature protected areas. The proposed approach does not exclude, but significantly reduces the volume of field investigations, and can significantly reduce the time and financial costs of creation of new protected areas to optimize the protection of rare and endangered plant species.