Institute of Geography, Russian Academy of Sciences

Modeling of the modern climatic range of a dangerous plant pest of the genus Buxus L. box tree moth Cydalima perspectalis (Walker, 1859) is carried out in order to determine possible territories of its further expansion in Eurasia. Information on the loci of actual C. perspectalis detection both in native (East and South Asia) and in invasive (Europe and West Asia) parts of the range was collected from various sources (species distribution databases and publications). Six bioclimatic (three temperature and three humidity) parameters are used as distribution predictors. Original methods for determining the number of pseudo-absence points and their selective generation are developed and applied. The final classification and partitioning of the space of bioclimatic factors is carried out using gradient boosting. The modern Eurasian climatic range of the box tree moth is calculated and mapped. It is shown that the invasion has not yet reached its limits and there are a number of territories in Eurasia where climatic conditions are favorable for the emergence of C. perspectalis populations both in the native part of the range (certain southern and eastern regions of China, the DPRK, the southern foothills of the Himalayas) and in its invasive part (Northern and Eastern Europe, Caucasus, and Turkey). A comparative assessment of the importance of different climatic factors in determining the area of box tree moth distribution is given. It has been found that the sum of precipitation of the driest month is of greatest importance for constructing a model of the climatic range of C. perspectalis (47.6%). A significant difference in climatic conditions between the native and invasive parts of the range is revealed and assumptions about the possible causes of its occurrence are made.

Bottom sediments of Lake Tere-Khol located in the southeast of the Sayan–Tuva Highland retained a detailed archive of landscape and climatic changes throughout the Holocene. This region is situated at the boundary between South Siberia and Central Asia and marks a transitional zone in terms of the factors that determined the hydroclimatic changes during the Holocene. The climate was mainly controlled by the western transport of Atlantic air masses north and west from the region and by the Asian-Pacific monsoon circulation to the south and east. The reconstruction of Holocene climatic changes in this region is crucial for understanding the dynamics of atmospheric circulation across the Eurasian continent’s interior. Stable isotope analyses in lacustrine carbonates were conducted to evaluate the Holocene humidity fluctuations. The water of Lake Tere-Khol is notably enriched in 18O and 2H by 6–8 and 50–60‰, respectively, compared to streams and rivers flowing in it, thus indicating a strongly evaporative water body. This suggests that the δ18O variations (14.1–20.0‰ SMOW) and their positive correlation with δ13C variations (–5.8 to 4.2‰ PDB) in the dispersed carbonate material of Holocene lacustrine sediments primarily reflect shifts in the hydrological regime. The positive δ18O and δ13C excursions correspond to the periods of aridification, while the negative excursions indicate phases of relative humidity. Three main humidity epochs were identified in the Holocene: relatively dry epochs from the initial Holocene to ~9.8 ka BP and from ~4.4 ka BP to the present, and a humid epoch between ~9.8 and ~4.4 ka BP. These phases were accompanied by a change of the second-order humidity. Thereby, the variability and amplitude of humidity fluctuations significantly increased in the second half of the Holocene, after approximately 6 ka BP. The most humid interval in the Holocene occurred between ~5.2 and ~4.4 ka BP. The sharp and significant aridification, the major hydroclimatic event in the Holocene, occurred at ~4.4 ka BP. The driest periods were observed between ~4.2 and ~3.1 ka BP and from ~1.9 to ~0.1 ka BP. At the turn of the eras around 2 ka BP and in the past century, these dry conditions were interrupted by short episodes of relative humidity. This Late Holocene aridification points to the weakening of the Pacific monsoon and the decrease of its penetration into the Eurasia’s interior, which aligns with cooling trends observed in the second half of the Holocene.

Four species of Eurasian badgers (Meles) are widely distributed across Eurasia. Small-sized and dark-coloured Far Eastern M. leucurus amurensis is the most distinctive form among all Asian badgers, M. leucurus. Traditionally, Far Eastern badgers are treated as a subspecies of the M. leucurus. This study aims to revise the geographical variability of the M. leucurus sensu lato from the entire species range (324 adult skulls) and assess the position of the Far Eastern badgers. In addition, 551 adult skulls of the European badger, M. meles, the Southwest Asian badger, M. canescens, and the Japanese badger, M. anakuma, were used for comparison with Asian badgers. Meles leucurus amurensis from the Far East resembles the Japanese M. anakuma in many respects, but is very different from the M. l. leucurus of southern Siberia and Middle Asia. Analysis of palaeontological data suggests that the Far Eastern badgers could have descended from the ancestral “leucurus-like” badger chronospecies known from China since the mid-Early Pleistocene. It then probably dispersed westwards into southern Siberia no later than the MIS9 stage (~ 0.32 Ma), where it evolved into M. leucurus. Previous molecular data suggest that the Japanese badgers are unique, whereas the Far Eastern badgers are closer to Asian badgers from the Urals, Siberia and Tibet. We propose that the Far Eastern badger retains some craniometrics features of the ancestral form of M. leucurus sensu stricto and M. anakuma and should therefore be considered a separate species, M. amurensis Schrenck, 1859 stat. rev. The presumed range of this species is in the Far East, east of the Great Khingan Range to Russian Primorye, Manchuria and the Korean Peninsula and possibly eastern China.

Desert varnish, or rock varnish, is a thin reddish-black microlayer that covers rocks and consists mainly of clay minerals, as well as oxides of iron and manganese. In this paper, both terms-desert and rock varnish-are used interchangeably. Rock varnish has been an object of study and interest for more than two centuries. As it develops mainly in arid and desert areas, the interactions between solar radiation, wind, humidity, and microbial activity are determining factors in its formation. The growth rate of a few microns per millennium suggests that rock varnish can function as a tool for recording past environments. The current work presents the state of knowledge of rock varnish, focusing mainly on inorganic studies. The formation theories, geographical location, magnetic properties, lithodiversity, climatic variability, dating insights, pedofeatures, and some historical aspects are discussed. In addition, the different analytical techniques that have been used to study varnish chemical and mineralogical composition are grouped. FIRST OBSERVATIONS AND HISTORICAL ASPECTS Due to its dark and shiny aspect, desert varnish is a striking superficial feature of arid landscapes and other predominantly extreme environments, such as high mountains, polar regions, etc. Without a doubt, this phenomenon was noticed already by early humans, a clear sign of this is the use of varnished surfaces to create petroglyphs by different prehistoric societies. Petroglyphs are images created by removing part of a rock surface by incising, pecking, carving, and abrading [3]. They are found all over the world and are a valuable source of information about the ancient cultures. Petroglyphs are often found in areas where desert varnish is present. The dark color of the varnish provides a contrasting background that makes the petroglyphs stand out. Thus, desert varnish serves as a canvas for these petroglyphs, allowing for preservation over long periods of time due to its unusual strength, durability, and chemical stability. Desert varnish has captivated the attention of scientists and naturalists for centuries. Already Alexander von Humboldt described dark patina on rock surfaces during his expeditions in the Orinoco River in Vene-zuela between 1799 and 1804. It was near some waterfalls where he first observed and documented a dark-brown rock cover in 1800 [213]. Humboldt was puzzled by the nature of these dark and bright coatings, as they did not show river components within them. This is how he proposed that there should be a chemical explanation for them to have significant amounts of iron and manganese oxides. Finally, he stated that the external conditions of the rock must be conditioning the "accretion" and "cementation" of the material and, therefore, the thicknesses of these coatings, ergo, was a phenomenon independent of the nature of the rocks [213]. On February 29, 1832, Charles Darwin would observe brown ferruginous coatings in Bahia, Brazil, referencing Humboldt's observations. He concludes that the origin of these "metal oxides" is GENESIS AND GEOGRAPHY OF SOILS

The area of primary boreal forest continues to decline due to anthropogenic disturbance, often targeting forests that provide the highest economic returns. This selective use of forests raises the question of whether the remaining primary forests occur within a subset of the environmental conditions present in their region of occurrence. We investigated whether and how the environmental conditions of primary boreal forests in Finland and northwestern Russia (Arkhangelsk, Karelia, Komi, and Murmansk) differ from those of their surrounding forests. To do this, we randomly selected 50 primary forests from each region and used openly available spatial data to quantify a set of variables describing topography, land cover, and accessibility for these primary forests and their surrounding forests. The remnant primary forests had different environmental characteristics compared with the surrounding forests in each study region. In terms of topography, the primary forests had either a higher absolute elevation or a higher topographic position than the surrounding forests. In Finland, the distance to rivers was also significantly higher in primary forests than in surrounding forests. The proportion of wetlands was high in the primary forests of Finland and Karelia, suggesting a high proportion of primary forests on organic soils. For all variables, the magnitude and occasionally even the direction of the difference between primary and surrounding forests varied between regions. In Finland and European Russia, the distribution of the remnant primary forests does not represent the full environmental variability present in their region of occurrence. This suggests that these forests do not only occur “high and far,” but within a subset of the environmental conditions present in these high and far regions. From a conservation perspective, primary forest attributes should be restored regionally, taking into account the diversity of environmental conditions that exist within the region.

The high variability of properties in urban soils and the abundance of anthropogenic inclusions that interfere with the propagation of electromagnetic fields are the reasons why they are seldom studied by geophysics. At the same time, geophysics is an efficient and fast way to diagnose soil structure and dynamics without affecting the functioning of the place, which is crucial when working in the city. In order to conduct a geophysical study of soils in the city, it is necessary to establish experimentally the relationship of electromagnetic properties with soil texture, moisture content, organic matter content, volume density of solid mineral matter, and some other characteristics of the soils. The purpose of our study was geophysical detection of spatial and temporal variations in urban soil properties using a lawn in Moscow as an example. Along with classical methods of soil description in reference pits and boreholes, we used ground-penetrating radar, electrical resistivity tomography, and electromagnetic induction methods in different seasons. To improve the accuracy of interpretation of geophysical data we analyzed the physical properties of soil horizons: particle size and water content, as well as electromagnetic parameters: complex dielectric permittivity and electrical resistivity. The integrated approach allowed to identify soil boundaries with a coefficient of determination of R2 = 0.54–0.88 and an error of 10 cm, to offer their interpretation and to study the seasonal dynamics of electromagnetic properties indirectly related to soil moisture.

Lithalsas are found on mires in the discontinuous permafrost in the circumpolar area of the northern hemisphere and in mountainous regions. The age and growth mechanism of lithalsa in the continental intermountain region of the East Sayan Mountains were uncertain and debated. We represent the results of a detailed analysis of four representative lithalsas, including ¹⁴ C dating, C‐N content of buried peat lenses, and organic matter from soils, as well as results of stable isotope measurements (δ ¹⁸ O and δ ² H) in the lithalsas' ice lenses. It was found that the studied lithalsas are not older than 600 years; the youngest mound began to form about 170 years BP. Main water sources for lithalsa ice formation were shallow lakes and the Sentsa River during spring floodings; freezing occurred mainly in open system conditions. However, the rate of freezing ice lens was not the same for the studied lithalsas, as well as the rate of their growth. Multiple freezing cycles were established for the highest lithalsa. High values of the C/N ratio in organic and peat horizons allow us to suppose the rapid freezing of organic matter during lithalsa growth. The findings confirm that non‐climatic factors, like flooding, are crucial for lithalsa dynamics.

The April-September maximum temperature in the Greater Caucasus region of Georgia has undergone notable changes, yet extended reconstructions remain scarce. We collected 40 Pinus sylvestris cores from Bakuriani and extracted their blue-intensity (BI) signals, which capture latewood density closely linked to high-season temperature. After chemical treatment and high-resolution scanning, we employed correlation analyses to identify the seasonal temperature signal in BI. Then, we used a linear regression model-validated by local instrumental records from 1950-2020-to reconstruct April-September temperatures back to 1780 CE. Additional superposed epoch analysis tested the reconstruction's responsiveness to significant volcanic eruptions and solar variability. Our reconstruction strongly correlates with observed data (r = 0.72, p < 0.001), revealing significant warming trends alongside cooling events linked to volcanic aerosols and low solar activity in recent decades. Spatial analyses confirm that the BI-derived temperature variations align well with broader regional climate patterns. Furthermore, CMIP6-based projections under high-emission scenarios suggest possible warming of up to 8.75°C by 2100, highlighting the severity of future climate risks in the region. By integrating BI data, linear regression techniques, and superposed epoch analysis, this research demonstrates the effectiveness of tree-ring proxies in capturing both anthropogenic and natural drivers of climate variability. The resulting 240-year temperature record provides valuable insights into historical climate dynamics, refines model predictions, and underscores the importance of localised, high-resolution data for adaptation planning in the Greater Caucasus region.

One of the characteristic ducks in Lake Mývatn, Iceland, has been the long-tailed duck (Clangula hyemalis) which was present in large numbers during the early 1900s but declined in numbers during the twentieth century. The long-tailed duck is a circumpolar sea duck, often with longitudinal migratory routes between wintering and breeding sites. In recent decades the species has been in decline throughout its range and it is now classified as vulnerable. In Iceland, the breeding population is 2000–3000 individuals, but the winter population is considerably larger (> 110,000) with wintering birds coming from other areas. To identify the phylogeographic origin of the species in Iceland, for both the breeding and the wintering population, variation in the control region of the mitochondrial DNA (mtDNA) was analyzed and compared with samples obtained from across the species range. Two distinct lineages of the control region were found in Iceland, one of which occurred at high frequency in the Icelandic breeding population. The haplotype lineage found in high frequency in the breeding population in Iceland was absent or in low frequencies elsewhere, except in the Yukon-Kuskokwim Delta, Alaska. The patterns observed in the mitochondria may reflect an overall genetic divergence of the Icelandic breeding population from the other sites studied or alternatively sexual differences in philopatry which may only affect the maternally transmitted markers.

Local anthropogenic sources of coarse aerosol (dust) in cities cause a “dust haze” effect on the territory adjacent to the source sites of such aerosol (construction sites, areas of reconstruction of roads and buildings), due to a sharp increase in the concentration of PM10 particles in the near-surface air. Two such episodes recorded in the center of Moscow in the summers of 2021 and 2024 are analyzed. The variability of the mass concentration and particle size distribution of dust aerosols under abnormally high atmospheric pollution (PM10 concentration above the maximum permissible concentration) is studied. A comparison of the characteristics of urban construction dust and arid aerosol in the atmosphere of the desert zones of Kalmykia showed similarities between them in the increased content of lithophilic elements (of natural origin). However, in the city, the concentrations of potentially toxic elements (heavy metals, metalloids, etc.) typical for urban dust are higher in aerosols from construction sources. The dust pollution of the megapolis atmosphere under the influence of intense construction sources not only worsens visibility and creates uncomfortable conditions for population living, but also creates great risks for the urban environment and human health.

In the current warming climate, many organisms in seasonal environments advance their timing of reproduction to benefit from resource peaks earlier in spring. For migrants, the potential to advance reproduction may be constrained by their migration strategies, notably their ability to advance arrival at the breeding grounds. Recent studies show various changes in migration strategies, including wintering closer to the breeding grounds, earlier departure from the wintering grounds or faster travels by spending less time at stopover sites. However, whether such changes lead to earlier arrival or earlier breeding remains an open question. We studied changes in migration and reproduction timing in 12 populations of nine migratory birds, including seabirds, shorebirds, birds of prey and waterfowl breeding at Arctic sites bordering the Greenland and Barents Sea, a region undergoing rapid climate warming. The timing of migration and reproduction was derived from tracking and field data and analysed to study (1) how timing has changed in response to the changing moment of snowmelt at the breeding grounds and (2) what adjustments in migration strategies this involved. We found that in years with early snowmelt, egg‐laying in multiple populations advanced, but only two waterfowl populations also advanced arrival in the Arctic. In contrast, arrival in the Arctic generally advanced with time, even when snowmelt or egg‐laying dates did not advance. Earlier arrival with time was mostly explained by populations traveling to the Arctic faster, likely spending less time at stopover sites. Inability to forecast conditions in the Arctic may limit birds to adjust migration timing to annually varying snowmelt, but we show that several species, particularly waterfowl, are able to travel faster and advance the timing of migration over the years. The question remains whether this reflects adaptations to Arctic climate change or other factors, for example, environmental changes along the migratory route.

This paper provides a review and comparison of the methods for assessing trends in the dynamics of alpine treeline (ATL) in high mountains are presented in. The methods analyzed are contemporary, traditionally used (dendrochronological and paleocarpological methods, retrospective analysis of historical photographs and geodetic surveying, and multi-temporal aerial photography), and innovative ones developed in recent decades (semi-automatic and automatic methods of interpretation of high-and medium-resolution space imagery and methods of space imagery interpretation using different techniques, such as classification, segmentation, vegetation index analysis, and machine learning algorithms). Different interpretations of the concept of 'alpine treeline' , which is currently established in geobotany and landscape sciences, are discussed. The attention to ATL dynamics is caused by global climate change's widespread forest increase and the decline in high mountain pastures. The ATL phenomenon's geographic map is condensed and displayed. There is an overview of the experience with different methods in varying mountain regions around the world. Each method is described in terms of its spatial scale, coverage, advantages, labor intensity, complexity, and limitations. It is shown that The effectiveness of the methods mainly depends on two key factors: the size of the area being studied and the time period over which changes are observed. The problem that still limits the use of remote sensing data is the contradiction between the accuracy of measurements and the coverage of the territories involved. To solve this problem, we suggest using a mix of methods that involve automatically classifying medium-resolution space images. This will be done by training on data collected from both fieldwork and lab experiments using different techniques.