Search Results (24)

Understanding how pollen assemblages represent the local and regional vegetation composition is crucial for palaeoecological research. Here, we analyze 102 surface moss/soil pollen samples collected from four study regions located in various boreal forest vegetation types in Central Siberia. Despite Larix being the most prevalent tree generus in the study area, the proportion of Larix pollen can be as low as 0.6–1.5% (0.4–4.7% on average) even in localities with a high canopy density of the species. No relationship between the quantity of Larix pollen in the spectra and the abundance of Larix in the local vegetation was found. The dominant components of the pollen assemblages are Betula and Alnus fruticosa. The pollen value of Picea is low (2.6–8.2% on average), with higher proportions at sample plots where spruce is abundant in forests. Pinus is a highly prevalent pollen species within its geographical range, comprising up to 40% of pollen assemblages. Outside of the range, the ratio of Pinus pollen was higher in habitats with low canopy density and in treeless ecosystems. The composition of herbaceous pollen and spores is significantly affected by the local plant community, offering more comprehensive insights into past vegetation patterns. Full article

This study presents the long-term forest history in the forest–tundra ecotone of the Low Yenisei River basin. The new high-resolution pollen and macroscopic charcoal data were inferred from the 8.6 m long peat archive covering the last 6300 years. Climate reconstructions are based on the application of the best modern analogue technique using pollen data. Our findings suggest an alternation of phases of middle-taiga forests of Larix sibirica, Abies sibirica, Picea obovata, and Pinus sibirica (intervals of climate warming: 6320–6050, 5790–5370, 4480–4220, and 3600–2700 cal yr BP, respectively) and open larch woodlands with the participation of Betula, Picea, and Pinus sibirica, typical for northern taiga (intervals of climate cooling and increasing humidification: 5370–4480, 4220–3600 cal yr BP, respectively). The vegetation pattern of the region became similar to the modern one around 2700 cal yr BP. Climate warming caused a northward shift of vegetation-zone boundaries in Yenisei Siberia and an expansion of the range of Abies sibirica by about 200 km to the north compared to the present day. The increased frequency of fires and biomass burning during warm periods may promote the melting of the local permafrost, thereby enhancing the tree growth and regeneration. Full article

Fe- and Al-rich metapelite from the Transangarian segment of the Yenisey Ridge (East Siberia, Russia) is a potential new source of high-alumina refractories. The rocks have relatively high average contents of Al₂O₃ (20 wt%) and Fe₂O₃ (7.91 wt%), moderate K₂O (3.44 wt%), and low CaO (0.74 wt%). Their dominant mineral assemblages are andalusite + muscovite + margarite + chlorite + biotite + quartz or staurolite + kyanite or/and andalusite + chlorite + muscovite + biotite + quartz with ±garnet and ±plagioclase. Al₂SiO₅ polymorphs occur as up to 1.5 cm andalusite porphyroblasts and partial or complete pseudomorphs after andalusite (kyanite and staurolite). Accessories include abundant Fe–Ti oxides and sporadic REE-, Y-, Ca-phosphates; sulfides are negligible. The composition of Al₂SiO₅ concentrates obtained in laboratory by heavy-media and magnetic separation from ≥0.06 mm fractions meet all requirements for raw material of this type: >56 wt% Al₂O₃, <42 wt% SiO₂, <1 wt% Fe₂O₃, <1.2 wt% TiO₂, and <0.2 wt% (CaO + MgO). The andalusite, kyanite, and mixed ores yield 0.7–4.1 wt%, 0.7–2.2 wt%, and 1.9–6.0 wt% of concentrate, respectively. The best-quality ores rich in Al₂SiO₅ polymorphs reside in zones of contact and/or dynamic metamorphism superimposed over regional metamorphism of Al-rich rocks. Full article

The characteristics of Abies sibirica Ledeb.- and Pinus sibirica Du Tour dominated forests stands in outbreak spots formed during a Dendrolimus sibiricus outbreak in 2014–2017 were studied at the stage of population collapse (east of the West Siberian Plain and western foothills of the Yenisei Range). The research was based on the data obtained during ground surveys conducted in 2016 when stands characteristics, the Siberian silk moth population density, and defoliation level were recorded. We classified the studied stands using decision trees and random forest algorithms to identify the key characteristics that determine the formation of outbreak spots. The classification results showed that the characteristics of the detected outbreak spots differ significantly from those previously described for dark coniferous stands of the southern taiga in Siberia. The highest probability of the outbreak spot occurrence in the study area was revealed for stands with the following characteristics: moderately moist site; Siberian stone pine and Siberian fir take 40% or more of stem volume; age of less than 105 years. Another group of forest stands under threat are those sharing the following characteristics: large area (more than 60 ha); stand homogeneity; ground vegetation is dominated by feather mosses; age of more than 120 years; Picea obovata Ledeb. takes a significant share in a stem volume. Such characteristics indicate that during the population collapse, the Siberian silk moth forms outbreak spots in stands that either undergo an early successional stage after previous outbreak or have been slightly damaged during the previous outbreaks due to unfavorable habitat conditions. Full article

The availability of clean drinking water impacts the quality of life of Arctic populations and is affected by climate change. We provide perceptions based on: (1) a study of the accessibility of the natural surface water to the nomadic and settled Indigenous inhabitants living in rural areas (in settlements and remote camps) in the Arctic zone of Western Siberia during climate change and industrial development; (2) an assessment of the impact of consuming different surface water resources on human health. We include primary data sources from medical examinations and surveys collected in the regions between the rivers of Ob, Nadym, Taz, and Yenisey in 2012, 2014–2019, and 2022 whereas the chemical analysis of the surface waters in the region was based on previous research. A total of 552 local residents from the Arctic zone of Western Siberia participated in the study. We discuss how the availability of high-quality drinking water is limited for them due to climatic and anthropogenic risks, despite the abundant water resources. The consumption of river water is associated with high health risks since it contains heavy metals (Pb, Cd, Mn, Fe), whereas the consumption of lake ice melt water likely affects health because of the low concentrations of beneficial ions. Full article

This study analyzed microplastics in the gastrointestinal tract of Siberian dace (Leuciscus leuciscus subsp. baicalensis (Dybowski, 1874)) in the remote Yenisei tributary of the Nizhnyaya (Lower) Tunguska River (Siberia, Russia). µRaman analysis showed that 60% of the fish from two different sites had ingested plastic microparticles (on average, 1.55 ± 1.95 items per individual). The most common type of microplastic were fibers, and the most abundant size category was 300 to 1000 µm. In the studied population, no significant differences in the MP content between the two sites or between males and females were found (p > 0.05). The tendency for higher MP ingestion by Siberian dace at earlier ages (2+ and 3+) compared to later (4+ and 5+) was observed, which may be connected to the features of the fish biology and ecology. Full article

The energy sector is one of the most important pollutants in the atmosphere and causes significant emissions of greenhouse gases. In Russia, coal is the main contributor to the fossil fuel consumption of thermal power plants and boilers, thus affecting atmospheric air pollution by releasing particulate matter and nitrogen oxides, which are strongly associated with a negative impact on human health. This problem is especially acute for the resource regions of Yenisei, Siberia, a 2.5+ mln sq km macro-region in the very heart of Russia. In this paper, we analyze the impact of the structure of electricity and heat generation on emissions of pollutants and climate-active gases in Yenisei, Siberia, and give an overview of their social, ecological, and economic effects. More than 75% of electricity in Yenisei, Siberia, is produced by hydroelectric power plants that do not pollute the atmosphere. The rest of the electricity is generated in the cogeneration mode by thermal power plants, which are cores of the heat supply designs of cities. The share of individual coal-powered heat sources is still high. A detailed analysis of existing equipment and technologies at existing thermal power plants is needed to select options for their modernization to reduce emissions while keeping coal in use. Our calculations for the biggest cities of Krasnoyarsk Krai show that investments in the transition to heating with pellets will require RUB 184.7 million for Nazarovo and RUB 313.9 million for Kansk. At the same time, switching to electric heating is more than twice as expensive: RUB 498.6 million for Nazarovo and RUB 847.5 million for Kansk. The additional costs will range from RUB 21 to RUB 45.4 thousand per household per year for the pellet variant and from RUB 56.8 to RUB 122.5 thousand per year for electric heating, which could triple the annual heating costs. Thus, these options are unlikely to be implemented without direct state support. We argue that creating an attractive living environment in Yenisei, Siberia, must begin with intensive public investment in mitigating the environmental externalities caused by coal emissions. Full article

Dissolved organic matter (DOM) is an important component of aquatic environments; it plays a key role in the biogeochemical cycles of many chemical elements. Using excitation–emission matrix fluorescence spectroscopy, we examined the fluorescent fraction of DOM (FDOM) produced at the stationary phase of growth of five strains of microalgae sampled and isolated from the Ob and Yenisei gulfs. Based on the morphological and molecular descriptions, the strains were identified as diatoms (Asterionella formosa, Fragilaria cf. crotonensis, and Stephanodiscus hantzschii), green microalgae (Desmodesmus armatus), and yellow-green microalgae (Tribonema cf. minus). Three fluorescent components were validated in parallel factor analysis (PARAFAC): one of them was characterized by protein-like fluorescence (similar to peak T), two others, by humic-like fluorescence (peaks A and C). The portion of fluorescence intensity of humic compounds (peak A) to the total fluorescence intensity was the lowest (27 ± 5%) and showed little variation between species. Protein-like fluorescence was most intense (45 ± 16%), but along with humic-like fluorescence with emission maximum at 470 nm (28 ± 14%), varied considerably for different algae strains. The direct optical investigation of FDOM produced during the cultivation of the studied algae strains confirms the possibility of autochthonous production of humic-like FDOM in the Arctic shelf regions. Full article

The tectonic evolution of the Siberian Cratonic margins offers important clues for global paleogeographic reconstructions, particularly with regard to the complex geological history of Central Asia and Precambrian supercontinents Columbia/Nuna and Rodinia and its subsequent breakup with the opening of the Paleo-Asian Ocean. Here, we present an overview of geochemical, petrological, and geochronological data from a suite of various rocks to clarify the age, tectonic settings, and nature of their protolith, with an emphasis on understanding the tectonic history of the Yenisey Ridge fold-and-thrust belt at the western margin of the Siberian Craton. These pre-Grenville, Grenville, and post-Grenville episodes of regional crustal evolution are correlated with the synchronous successions and similar style of rocks along the Arctic margin of Nuna-Columbia and Rodinia and support the possible spatial proximity of Siberia and North Atlantic cratons (Laurentia and Baltica) over a long period ~1.4–0.55 Ga. Full article

Observations of the atmospheric sources and sinks of carbon dioxide (CO₂) and methane (CH₄) in the pan-Arctic domain are extremely scarce, limiting our knowledge of carbon turnover in this climatically sensitive environment and the fate of the enormous carbon reservoirs conserved in the permafrost. Especially critical are the gaps in the high latitudes of Siberia, covered by the vast permafrost underlain tundra, where only several atmospheric monitoring sites are operational. This paper presents the first two years (September 2018–January 2021) of accurate continuous observations of atmospheric CO₂ and CH₄ dry mole fractions at the recently deployed tower-based measurement station “DIAMIS” (73.5068° N, 80.5198° E) located on the southwestern coast of the Taimyr Peninsula, Siberia, at the Gulf of the Yenisei River that opens to the Kara Sea (Arctic Ocean). In this paper, we summarized the scientific rationale of the site, examined the seasonal footprint of the station with an analysis of terrestrial vegetation and maritime sector contributing to the captured atmospheric signal, and illustrated temporal patterns of CO₂ and CH₄ for the daytime mixed atmospheric layer over the continent–sea interface. Along with the temporal variations reflecting a signal caused pan-Arctic and not very much influenced by the local processes, we analyzed the spatiotemporal distribution of the synoptic anomalies representing the atmospheric signatures of regional sources and sinks of CO₂ and CH₄ for the studied high-arctic Siberian domain of ~625 thousand km², with nearly equal capturing the land surface (54%) and the ocean (46%) throughout the year. Both for CO₂ and CH₄, we have observed a sea–continent declining trend, presuming a larger depletion of trace gases in the maritime air masses compared to the continental domain. So far, over the Kara Sea, we have not detected any prominent signals of CH₄ that might have indicated processes of subsea permafrost degradation and occurrence of cold seeps–still mainly observed in the eastern Arctic Seas—The Laptev Sea and the East-Siberian Sea. Full article

The pine looper Bupalus piniaria (L.) is one of the most common pests feeding on the Scots pine Pinus sylvestris L. Pine looper outbreaks show a feature of periodicity and have significant ecological and economic impacts. Climate and weather factors play an important role in pine looper outbreak occurrence. We tried to determine what weather conditions precede B. piniaria outbreaks in the southeast of the West Siberian Plain and what climate oscillations cause them. Due to the insufficient duration and incompleteness of documented observations on outbreaks, we used the history of pine looper outbreaks reconstructed using dendrochronological data. Using logistic regression, we found that the factor influencing an outbreak the most is the weather four years before it. A combination of warm spring, dry summer, and cool autumn triggers population growth. Summer weather two years before an outbreak is also critical: humidity higher than the average annual value in summer is favorable for the pine looper. The logistic regression model predicted six out of seven outbreaks that occurred during the period for which weather data are available. We discovered a link between outbreaks and climatic oscillations (mainly for the North Atlantic oscillation, Pacific/North America index, East Atlantic/Western Russia, West Pacific, and Scandinavian patterns). However, outbreak predictions based on the teleconnection patterns turned out to be unreliable. We believe that the complexity of the interaction between large-scale atmospheric processes makes the direct influence of individual oscillations on weather conditions relatively small. Furthermore, climate changes in recent decades modulated atmospheric processes changing the pattern predicting pine looper outbreaks: Autumn became warmer four years before an outbreak, and summer two years before became drier. Full article

This study is a pioneering attempt to count microplastics (MPs) in the Yenisei River system to clarify the role of Siberian Rivers in the transport of MPs to the Arctic Ocean. The average MPs content in the surface water of the Yenisei large tributary, the Nizhnyaya Tunguska River, varied from 1.20 ± 0.70 to 4.53 ± 2.04 items/m³, tending to increase along the watercourse (p < 0.05). Concentrations of MPs in bottom sediments of the two rivers were 235 ± 83.0 to 543 ± 94.1 with no tendency of downstream increasing. Linear association (r = 0.952) between average organic matter content and average counts of MPs in bottom sediments occurred. Presumably MPs originated from the daily activities of the in-situ population. Further spatial-temporal studies are needed to estimate the riverine MPs fluxes into the Eurasian Arctic seas. Full article

This study reports a synthesis of years-long hydrogeochemical monitoring in northern West Siberia, performed by the Russian Meteorological Service (Rosgidromet) and several academic institutions. Natural factors and intensive human economic activity lead to the disruption of the ecosystems of the northern territories of Western Siberia. The aim of this study is to estimate the background water chemistry parameters in the rivers of northern West Siberia in the beginning of the 21st century. The mean values hydrochemical and geochemical indicators were determined with STATISTICA software, which can be used as background values in assessing the actual and allowable anthropogenic impact on water bodies. We revealed four water chemistry provinces: western Ob Gulf and Ob estuary catchments (I); eastern Ob Gulf and Taz Gulf catchments, except for the Taz River and its tributaries (II); Taz River catchments (III); Yenisei River catchments, right bank (IV). The major-ion chemistry of the sampled river waters records a combination of geological, geomorphological, and hydrological conditions in the four provinces. The features typical of the northern West Siberian Plain are especially prominent in province II, which has the lowest average total of major ions (Σ_mi), the highest chemical oxygen demand (potassium dichromate COD), and the highest contents of Fe and phosphates. The Σ_mi value is the highest in province IV. The river waters from four provinces share similarity in quite high organic contents (both potassium dichromate and permanganate COD), as well as high NH₄⁺ and Fe. The long-term average Σ_mi of the waters is predicted not to change much in the coming one or two decades, though it may decrease slightly in the winter season but increase in the fall and spring time. Full article

Environmental problems of urban and rural areas are now high on the agenda of industrialized countries, becoming a key challenge for regional-level policymaking. The mutual influence of population growth, economic and technological development, and the anthropogenic pressure on the environment is still insufficiently studied in many countries, including Russia. In this paper, this relationship is studied for the municipalities of Angara–Yenisey Siberia using an ensemble of the STIRPAT-like regression models, adapted according to the available data. We found that population size and gross municipal product were positively associated with pollutant emissions (p < 0.01), while energy efficiency had no significant impact on air pollution. In addition to the poor national data quality and completeness issues, which can distort statistical conclusions, the cause of the observed lack of spatial correlation between energy efficiency and air pollutant emissions may be path dependence and an insufficient pace of transition to a greener economy. This leaves room for institutional transformations aimed at intensifying energy efficiency to reduce the environmental burden. Full article

This study reconstructs the depositional conditions of ironstones within the Chulym-Yenisey basin and assesses the iron source. The detrital minerals of the studied deposits include quartz and feldspar. The authigenic minerals are goethite, siderite, aragonite, dolomite, calcite, apatite, barite, and pyrite. The clay components include minerals of the chlorite group (possible chamosite), nontronite, kaolinite, illite, and beidellite. Local bacterial sulfate reduction led to the formation of pyrite framboids in siltstone layers. The subsequent diagenetic iron reduction promoted the formation of chamosite from siderite. The goethite precipitation occurred in an oxidic aqueous environment. The Cretaceous continental sediments of the Ilek and Kia Formations of the Chulym-Yenisei depression consist of fine- and medium-grained, cross-stratified, poorly sorted litho-feldspatho-quartzose sandstones of fluvial channel origin alternating with bluish-gray siltstones and ironstones of floodplain–lacustrine–bog origin. Thin layers of iron-bearing rocks within siltstones formed in meromictic waters. The changes in geochemical proxies demonstrate fluctuations of paleoenvironmental conditions within the Cretaceous sequence. Siltstones and sandstones formed under humid and arid conditions, respectively. The primary iron source for sediments of the Chulym-Yenisey depression was determined as volcanogenic and igneous rocks of the Altai-Sayan mountainous region. Full article