Western Sayan Research Articles

First findings of platinum group minerals from ultramafites of the Idzhim mafic-ultramafic massif (Western Sayan)

In plastically deformed harzburgite and dunite of the Idzhim mafic-ultramafic massif, which is part of the Kurtushiba ophiolite belt of the Western Sayan and is one of largest massifs of this belt, platinum group minerals (PGM) were identified for the first time. They were found in pentlandite, awaruite and nickel arsenides (NiS, Ni2S) in form of finely dispersed inclusions, the diagnosis of which, due to their small size, was carried out only qualitatively. Native osmium, Ir-bearing osmium, native ruthenium, garutiite, tetraferroplatinum, unnamed (Pt,Ir)Fe and (Ni,Cu,Pd,Pt)2-3Fe phases, zaccarinite, Ir-bearing erlikmanite and unnamed sulfides with crystal chemical formula Me2S were quantitatively identified and characterized. All PGM grains found are predominantly localized either in peripheral parts of grains of sulfides, awaruite and wairauite, or in silicate matrix in immediate vicinity of these minerals. The platinum group elements (PGE) content and their distribution in restite ultramafic rocks was apparently controlled by partial melting of primary peridotite substrate. During partial melting, the extraction of sulfur and Pt-group platinoides (Pt, Pd, Rh) into the silicate melt led to a decrease in S2 fugacity and the accumulation of Ir-group platinoides (Os, Ir, Ru) in monosulfide solid solution (mss), from which subsequently primary Os-Ir-bearing pentlandite crystallized. The subsequent transformation of this sulfide led to appearance of PGE-containing awaruite and nickel arsenides, as well as to everything discovered diversity of identified PGM.

New records of two rare species of green algae (Chlorophyta) from snowfields of the Subpolar Urals and the Western Sayan

New records of two rare species of green algae (Chlorophyta) from snowfields of the Subpolar Urals and the Western Sayan

Species diversity and structure of the fish community in different types water bodies of the Ergaki natural park (Western Sayan)

The Yenisei is one of the largest rivers on our planet. Flowing from south to north, it crosses all the natural zones of Siberia. The Yenisei basin covers the mountains and intermountain hollows of the Altai-Sayan mountainous country, the plateaus of Central and the lowlands of Western Siberia. The ichthyofauna of the flat part of the Yenisei basin is relatively well studied, while the data on the fish of the water bodies of the Western Sayan which are part of the Yenisei basin is limited in the available literature, and includes information only about the fish of some lakes. In this work, we studied of the ichthyofauna and the fish community of different types of water bodies in a specially protected natural area in the central part of the Western Sayan, in the Ergaki Natural Park — the Nizhnyaya Buiba and Bolshaya Oya rivers, and information about the ichthyofauna of Lake Oyskoye was clarified. In the studied water bodies, three species of fish (typical for rivers and lakes of the mountains of southern Siberia) were identified: Arctic grayling Thymallus arcticus (Pallas, 1776), Siberian loach Barbatula toni (Dybowski, 1869) and Eurasian minnow Phoxinus phoxinus (Linnaeus, 1758). Previously there was no information about the presence of Siberian loach in water bodies on the territory of the Ergaki Natural Park in the available scientific literature. The abundance and biomass of fish species varies significantly in different water bodies. Arctic grayling is common or dominant in rivers, Eurasian minnow is super dominant in the Nizhnyaya Buiba river and in the Oyskoe lake. In the Bolshaya Oya river, the superdominant species is the Siberian loach. Eurasian minnow in the Oyskoe lake is large of size.

Wood anatomy chronologies of Scots pine in the foothills of the Western Sayan (Siberia)

Wood anatomy chronologies of Scots pine in the foothills of the Western Sayan (Siberia)

Shift of the Yenisei and Abakan Beds as Reasons for Constructing the Second Abakan Fort in 1707

The study explores the reasons behind the relocation of the construction site for Fort Abakan from the mouth of the Abakan River, as initially planned, to the right bank of the Yenisei River, between two mountains, Unyuk and Turan. The shift of sand ridges, damming these rivers and changing their beds, is examined, and the locations of the projected forts are described. Written sources suggest that the Abakan and Yenisei beds as related systems changed their positions simultaneously, likely between 1691 and 1697 and definitely no earlier than 700–400 BC. Modern hydrological data suggest that processes that occurred in the region in the Early Modern Age were essentially like those that occurred in the Early Iron Age. The earlier date of the Abakan bed’s change is evidenced by the destruction of the 1st millennium BC Tagar sites near Sartykov village on the Abakan. At present, the Yenisei makes an abrupt eastward turn in that place, following the general direction of rivers in the region. D.A. Klements’s idea that after leaving the Western Sayan canyon, the Yenisei had flowed westwards is rejected. The change of location for the prospective fort was caused by the evolution of riverine systems of Western Siberia, specifically by the shift in the Abakan bed.

Climatic Effects on Position and Dynamics of Upper Open Forest Boundary in Altay and Western Sayan in the Last 60 Years

The upper treeline ecotone is a global and typically climate-dependent phenomenon. Its elevation is usually coupled with the thermal limitations of tree growth. The air temperature rise connected with global warming is assumed as the main cause of treeline upslope shifts in the last century. It has been found that the treeline elevation also correlates with the distance from the coastline and the aridity or continentality of the climate or the mass elevation effect. However, previous and contemporary publications have not explained how the upper treeline position directly couples with climate parameters. Often, this has been restricted by a lack of climate measurements and spatial data. In our study, we obtained data from 339 regional weather stations for 1964–1974 and interpolated them to Altay and Western Sayan using regional DEMs and a specially developed regression model. Moreover, we semiautomatically identified the elevational position of the upper open forest boundary (OFB) (crown closure > 10%) on the slopes of 30 mountains in Altay and Western Sayan in 1960 and 2020. We took into account the slope aspect and edaphic constraints. The obtained data allowed us to undertake a regression analysis of the dependence of the OFB elevation on climatic parameters. As a result, we found that, in the 1960s, at OFB elevations rising from the outer to the inner parts of the study area to approximately 500–700 m, the summer air temperature and precipitation linearly decreased, but the summer sunshine duration increased. In the multiple regression analysis, including the climatic parameters as independent variables and the OFB elevation as a dependent variable, significant relations were found only for the combination of air temperature and sunshine duration. We assume that the OFB elevation is determined not only by the air temperature but also by the direct solar irradiation level, changing with latitude and cloudiness. We also found that the ratio between the OFB elevation on the northern and southern slopes varied with respect to latitude. The spatial analysis of OFB shifts in 1960–2020 revealed significant differences in its value in the central (80–90 m) and outer parts of the study area (110–130 m). We suppose that the OFB advance over the past 60 years has local specificity associated with the peculiarities of the climatic changes (summer temperature rise, precipitation decrease, and sunshine duration increase) in different parts of Altay and Western Sayan. Our results highlight the need to clearly determine climatic parameters when forecasting woody vegetation reactions to future climate changes.

Modeling of the Statistical Distribution of Tracheids in Conifer Rings: Finding Universal Criterion for Earlywood-Latewood Distinction.

The quantitative description of growth rings is yet incomplete, including the functional division into earlywood and latewood. Methods developed to date, such as the Mork criterion for conifers, can be biased and arbitrary depending on species and growth conditions. We proposed the use of modeling of the statistical distribution of tracheids to determine a universal criterion applicable to all conifer species. Thisstudy was based on 50-year anatomical measurements of Pinus sylvestris L., Pinus sibirica Du Tour, and Picea obovata Ledeb. near the upper tree line in the Western Sayan Mountains (South Siberia). Statistical distributions of the cell wall thickness (CWT)-to-radial-diameter (D) ratio and its slope were investigated for raw and standardized data (divided by the mean). The bimodal distribution of the slope for standardized CWT and D was modeled with beta distributions for earlywood and latewood tracheids and a generalized normal distribution for transition wood to account for the gradual shift in cell traits. The modelcan describe with high accuracy the growth ring structure for species characterized by various proportions of latewood, histometric traits, and gradual or abrupt transition. The proportion of two (or three, including transition wood) zones in the modeled distribution is proposed as a desired criterion.

Dissolved Carbon Concentrations and Emission Fluxes in Rivers and Lakes of Central Asia (Sayan–Altai Mountain Region, Tyva)

The carbon (C) cycle in inland waters, including carbon concentrations in and carbon dioxide (CO2) emissions from water surfaces, are at the forefront of biogeochemical studies, especially in regions strongly impacted by ongoing climate change. Towards a better understanding of C storage, transport and emission in Central Asian mountain regions, an area of knowledge that has been extremely poorly studied until now, here, we carried out systematic measurements of dissolved C and CO2 emissions in rivers and lakes located along a macrotransect of various natural landscapes in the Sayan–Altai mountain region, from the high mountains of the Western Sayan in the northwest of Tyva to the arid (dry) steppes and semideserts in the intermountain basins in the southeast of Tyva on the border with Mongolia. New data on major hydrochemical parameters and CO2 fluxes (fCO2) gathered by floating chambers and dissolved organic and inorganic carbon (DOC and DIC, respectively) concentrations collected over the four main hydrological seasons allowed us to assess the current C biogeochemical status of these water bodies in order to judge possible future changes under climate warming. We further tested the impact of permafrost, river watershed size, lake area and climate parameters as well as ‘internal’ biogeochemical drivers (pH, mineralization, organic matter quality and bacterial population) on CO2 concentration and emissions in lakes and rivers of this region and compared them with available data from other subarctic and mountain settings. We found strong environmental control of the CO2 pattern in the studied water bodies, with thermokarst lakes being drastically different from other lakes. In freshwater lakes, pCO2 negatively correlated with O2, whereas the water temperature exerted a positive impact on pCO2 in large rivers. Overall, the large complexity of counteracting external and internal drivers of CO2 exchange between the water surfaces and the atmosphere (CO2-rich underground DIC influx and lateral soil and subsurface water; CO2 production in the water column due to dissolved and particulate OC biodegradation; CO2 uptake by aquatic biota) precluded establishing simple causalities between a single environmental parameter and the fCO2 of rivers and lakes. The season-averaged CO2 emission flux from the rivers of Tyva measured in this study was comparable, with some uncertainty, to the C uptake fluxes from terrestrial ecosystems of the region, which were assessed in other works.

The mayflies (Ephemeroptera) of the Us River basin in the Western Sayan mountains, Russia

The mayflies (Ephemeroptera) of the Us River basin in the Western Sayan mountains, Russia

Genetic legacy of southern Middle Siberian mountain and foothill populations of Scots pine (Pinus sylvestris L.): Diversity and differentiation

Scots pine (Pinus sylvestris L.) is a widespread and economically important tree species in Eurasia. Southern Siberian, Scots pine mountain and foothills forests are especially valuable natural objects that help to stabilize environmental conditions. Due to the associated impact of natural and anthropogenic factors, the habitats of the species in southern Siberia are constantly shrinking. In this regard, the study of genetic diversity and structure of Scots pine forests in southern Siberia is very relevant. Here, we studied the genetic diversity and structure of eight Scots pine populations located in southern Middle Siberia (Russia). A high level of genetic diversity (HE = 0.518) was detected in the studied populations. No recent bottleneck effect, isolation by distance or isolation-by-environment were detected. Most genetic diversity was found within populations, while only 7% of genetic diversity occurred among populations. Both STRUCTURE analysis and UPGMA clustering showed two genetic groups. Two populations from the Minusink basin and a population from the Western Sayan Mts. formed the first group and the second group was composed of the other populations from Kuznetsk Alatau Mts., Central Tuva basin and Todzha basin. Our findings suggest that the studied Scots pine populations originate from different gene pools. The pattern of genetic diversity revealed by our study may be useful for the elaboration of conservation measures of genetic resources of Scots pine in southern Middle Siberia.

SIGNS OF VITAL ACTIVITY OF BROWN BEAR IN THE SUBALPINE BELT OF THE WESTERN SAYAN MOUNTAINS

Brown bear ( Ursus arctos L.) populations in the forest zone form communicative systems of marks left primarily on trees. This species also inhabits areas with low forest cover, including the subalpine belt. We studied the communication systems of brown bear populations in 2007-2009 in the Western Sayan, in the Ergaki natural park. The purpose of the study was to identify signs of the life activity of the brown bear in the subalpine belt, which could be used by these animals for indirect communication. We registered a total of 120 bear trees (BT) among which Siberian pine ( Pinus sibirica ) prevailed (83.3%). The linear frequency of marking was registered low: 2.66 BT per 10 km of the route. We found increased incidence of damaging marks and footprint marks left by adult males. Cluster analysis of data by 15 types of bear marks revealed two major groups: marks left by adult males and “marks” that bears of all age and sex groups are capable to leaving on BT.

The Curious Case of Fritillaria sonnikovae (Liliaceae) in South Siberia: New Insights into Its Origin and Phylogeny

Fritillaria Tourn. ex L. is a genus of Liliaceae including a little more than 150 species occurring in the temperate Holarctic. Fritillaria sonnikovae Shaulo & Erst is the most recently described Siberian species in the genus. In the affinity section of the F. sonnikovae diagnosis, only F. dagana Turcz. and F. roylei Hook. are mentioned. Our study is an original attempt to shed light on the F. sonnikovae origin and its evolutionary relationships with other Fritillaria using nuclear (ITS) and plastid (matK + rps16 + trnH-psbA) DNA markers. Our results showed that F. sonnikovae together with F. dagana and F. maximowiczii Freyn belongs to the North Asian lineage of the Liliorhiza subgenus and produced no evidence supporting relationship between F. sonnikovae and F. roylei. Monophyly of Fritillaria sonnikovae was not reliably confirmed in our study since its close affinity with F. maximowiczii was demonstrated by phylogenetic analysis and morphology. Fritillaria dagana was shown to be a sister to the F. maximowiczii + F. sonnikovae group. Most authors of the present study suggest considering F. sonnikovae as a synonym for F. maximowiczii. In this view, F. sonnikovae may be considered a narrow endemic and one of the light-perianth morphs of F. maximowiczii, which has emerged in the Western Sayan and remained there as a tertiary relict.

Plans for the Construction of Russian Forts in the Western Sayan Mountains and the Second Krasnoyarsk “Rebellion” (“Shatost”) (1718–1720)

The history of the construction of Russian fortresses (ostrog) in Siberia offers many examples, of when due to various circumstances their rapid and full-fledged building, as well as effective use failed. This is also relevant for the time of construction of new fortification facilities in the basin of the Middle and Upper Yenisei during the exploration of these territories. As a result of the conflict (“rebellion”, “shatost”) between the local administration of the Krasnoyarsk district and the garrison the latter delayed or even refused to build fortresses. The article is aimed to identify and chara terize the facts related to these phenomena. It considers the case, when, because of the actions and decisions of the all-Siberian and local administrations in a conflict with the garrison and the population of the Krasnoyarsk ostrog and the district in 1718–1720, the construction of the fort beyond the Sayan (modern Tuva), on the territory that was in the actual possessions of the Mongol khans, who were subjects of the Qing empire, was terminated. These events, rarely being in the focus of research, were called the second Krasnoyarsk “rebellion”. The article identifies and characterizes the circumstances related to it, assess their influence on decisions toward the construction of new forts, analyzes the activities of the central and local administrations to overcome such crisis situations, highlights the consequences of these actions, etc. It concludes by discussing some of the quality and features of the defense policy, regarding defense infrastructure in particular, in Siberia at the beginning of the 18th century.

Степной орёл в Алтае-Саянском регионе – результаты исследований 2019–2023 годов

Степной орёл в Алтае-Саянском регионе – результаты исследований 2019–2023 годов

Timberline and treeline dynamics: Pinus sibirica trees move

In the context of climate change, one of the important issues in assessing the state of mountain forest ecosystems is the study of the upward movement of the tree line (tree line) and forest line (timberline). To determine the potential of a particular species when moving up the slope, the functional characteristics of the needles are of great importance. This paper considers changes in the pigment composition of needles and the depth of winter dormancy of two coniferous species Pinus sibirica and Abies sibirica growing in the area of the Ergaki Ridge of the Western Sayan.

The First Occurrence of Platinum Group Minerals in Ultramafic Rocks of the Kyzyr–Burlyuk Massif (Western Sayan Mountains, Russia)

The First Occurrence of Platinum Group Minerals in Ultramafic Rocks of the Kyzyr–Burlyuk Massif (Western Sayan Mountains, Russia)

Spatial-Coherent Dynamics and Climatic Signals in the Radial Growth of Siberian Stone Pine (Pinus sibirica Du Tour) in Subalpine Stands along the Western Sayan Mountains

Siberian stone pine (Pinus sibirica Du Tour) is one of the keystone conifers in Siberian taiga, but its radial growth is complacent and thus rarely investigated. We studied its growth in subalpine stands near the upper timberline along the Western Sayan Mountains, Southern Siberia, because climatic responses of trees growing on the boundaries of species distribution help us better understand their performance and prospects under climate change. We performed dendroclimatic analysis for six tree-ring width chronologies with significant between-site correlations at distances up to 270 km (r = 0.57–0.84, p < 0.05). We used ERA-20C (European Reanalysis of the Twentieth Century) daily climatic series to reveal weak but spatially coherent responses of tree growth to temperature and precipitation. Temperature stably stimulated growth during the period from the previous July–August to current August, except for an adverse effect in April. Precipitation suppressed growth during periods from the previous July–September to December (with reaction gradually strengthening) and from the current April to August (weakening), while the snowfall impact in January–March was neutral or positive. Weather extremes probably caused formation of wide tree rings in 1968 and 2002, but narrow rings in 1938, 1947, 1967, 1988, and 1997. A subtle increase in the climatic sensitivity of mature trees was observed for all significant seasonal climatic variables except for the temperature in the previous October–January. The current winter warming trend is supposedly advantageous for young pine trees based on their climatic response and observed elevational advance.

Eranthis Salisb. (Ranunculaceae) in South Siberia: Insights into Phylogeography and Taxonomy

Eranthis Salisb. (Ranunculaceae) is a herbaceous plant genus, including few species disjunctively distributed throughout the temperate zone from Southeastern Europe to Eastern Asia. Until recently, only Eranthis sibirica DC. was known in South Siberia, being considered endemic and tertiary relict. Not long ago, Eranthis tanhoensis Erst was also described in Siberia. We report here a reconstruction of the phylogenetic relationships between the Siberian Eranthis species based on nuclear (ITS) and plastid (trnL + trnL-trnF + trnH-psbA) DNA. The phylogeographic structure of Siberian Eranthis is distinguished by the presence of the two “eastern” and “western” supergroups, which most likely formed as a result of disjunction caused by active mountain uplifts during the late Neogene–early Quaternary and subsequent progressive Pleistocene cooling. The eastern supergroup combines lineage I, containing populations from the eastern Khamar-Daban Ridge, the Eastern Sayan Mountains, and the Tannu-Ola Ridge, and lineage II containing western Khamar-Daban populations. The western supergroup includes only lineage III, containing Western Sayan populations. Our data clearly show that E. tanhoensis is nested in the E. sibirica clade, thereby indicating that its description as a separate species is unjustified, as it compromises the monophyletic status of E. sibirica. Therefore, we suggest here to consider E. tanhoensis as a synonym of E. sibirica.

Medieval Quarry Near the Koksa Bay (Krasnoyarsk Reservoir) as the Evidence of Possible Migration of the Yenisei Kyrgyz from the Sayan Mountains to the Middle Yenisei

Purpose. The results of archaeological survey in 2021 along the western shore of the Krasnoyarsk reservoir in the Koksa Bay area are presented in the process of field research. Previously unknown cultural and historical objects were revealed – a quarry on Mount Bol’shoi Togurtag, presumably of medieval times, and mounds in the form of rounded stone objects at the foot of the mountain 1 250 m from the Koksa bay.Results. The material extracted from the quarry was used in the construction of these mounds, located at the foot of the mountain. This assumption is evidenced by a similar type of rock in the quarry and on the mounds (they are of magmatic origin). Previously, similar objects for this territory were not mentioned in the scientific literature. Is the technological originality in stone processing techniques evidence of the migration to this territory of any mobile group of the population from the outside, where such technology was traditional? For example, medieval Kyrgyz kurgans in the Usinsk valley of the Western Sayan, where there are many rocks of igneous origin, are similar to them in their appearance and composition of the building material. Therefore, it is logical to assume that here, on the Middle Yenisei, some group of “Usintsy” migrated, which was quite likely as part of the process of returning to their homeland of the Yenisei Kyrgyz after the Great Power era. An exhaustive answer to this question can be given in the future only after an archaeological study of the rounded stone structures located here, similar to medieval “сhaatas” and “suukter” mounds, but composed, as indicated, of material of magmatic origin, unusual for this territory, in the form of large and medium-sized blocks of “torn” forms.Conclusion. The quarry on Bol’shoi Togurtag Mount demonstrates more labor-intensive process of obtaining stone material in comparison even with the extraction of “slabs” from layers of Devonian sandstone for the construction of mounds of the Tagar culture. All of the above and determines the originality of this object among those known in Khakassia. In this regard, their further study seems to be very relevant and expedient for the formation of a complete picture of the origin of medieval archaeological sites on the left bank of the Yenisei.

Mineralogy and genesis of ultramafic rocks from the Kurtushiba ophiolite belt (Western Sayan)

The studies of minerals and melt inclusions in ultramafc rocks of the Kurtushiba ophiolite belt (Western Sayan) allowed us to establish the conditions of mineral-forming processes during their formation. . The features of the compositions of minerals of ultramafc rocks of Idzhim, Kalny and Ergaki massifs are considered. The presence of melt inclusions directly indicates a magmatic origin of some Cr-spinels from dunites of Idzhim massif. A close assemblage of Cr-spinels from chromitites with magmatic Cr-spinels is important because of the possible formation of chromite ore from melts. The study of melt inclusions revealed the evolution of melts (picrites – picrobasalts – basalts – basaltic andesites) during the consecutive crystallization of minerals from the Western Sayan ophiolites. Computational modeling based on the compositions of melt inclusions and olivine indicates that olivine of ultramafc rocks of the Kurtushiba ophiolites crystallized at a decreasing pressure from 9.2 to 6.2 kbar and decreasing temperature from 1550 to 1430 °С from picritic melts, which evolved to picrobasaltic melts. With a decrease pressure to 3.8–2.3 kbar and temperature of picrobasaltic melts (1240–1230 °C), the formation of olivine terminated following by the crystallization of clinopyroxene from basaltic magmas at 2.7–1.9 kbar and about 1215 °C. The postmagmatic stage was characterized by plastic deformations of the Western Sayan ultramafc rocks at a decreasing temperature from 850 to 640 °C, which resulted in a successive change from protogranular to mesogranular structures and then to porphyroclastic and porphyroleist structures.