Subarctic Regions Research Articles

Dissolved Metal (Fe, Mn, Zn, Ni, Cu, Co, Cd, Pb) and Metalloid (As, Sb) in Snow Water across a 2800 km Latitudinal Profile of Western Siberia: Impact of Local Pollution and Global Transfer

Snow cover is known to be an efficient and unique natural archive of atmospheric input and an indicator of ecosystem status. In high latitude regions, thawing of snow provides a sizable contribution of dissolved trace metals to the hydrological network. Towards a better understanding of natural and anthropogenic control on heavy metals and metalloid input from the atmosphere to the inland waters of Siberian arctic and subarctic regions, we measured chemical composition of dissolved (<0.22 µm) fractions of snow across a 2800 km south–north gradient in Western Siberia. Iron, Mn, Co, Ni, and Cd demonstrated sizable (by a factor of 4–7) decrease in concentration northward, which can be explained by a decrease in overall population density and the influence of dry aerosol deposition. Many elements (Mn, Ni, Cu, Cd, Pb, As, and Sb) exhibited a prominent local maximum (a factor of 2–3) in the zone of intensive oil and gas extraction (61–62° N latitudinal belt), which can be linked to gas flaring and fly ash deposition. Overall, the snow water chemical composition reflected both local and global (long-range) atmospheric transfer processes. Based on mass balance calculation, we demonstrate that the winter time atmospheric input represents sizable contribution to the riverine export fluxes of dissolved (<0.45 µm) Mn, Co, Zn, Cd, Pb, and Sb during springtime and can appreciably shape the hydrochemical composition of the Ob River main stem and tributaries.

How to thrive in unstable environments: Gene expression profile of a riparian earthworm under abiotic stress

Nowadays, extreme weather events caused by climate change are becoming more frequent. This leads to the occurrence of extreme habitats to which species must adapt. This challenge becomes crucial for species living in unstable environments, such as the riparian earthworm Eiseniella tetraedra. Its cosmopolitan distribution exposes it to various environmental changes, such as freezing in subarctic regions or droughts in Mediterranean areas. Transcriptional changes under cold and desiccation conditions could therefore shed light on the adaptive mechanisms of this species. An experiment was performed for each condition. In the cold experiment, the temperature was lowered to −14 °C ± 2 °C (compared to 8 °C for control samples), and in the desiccation treatment, humidity was lowered from 60% to 15%. Comparisons of gene expression levels between earthworms under freezing conditions and control earthworms revealed a total of 84 differentially expressed genes and comparisons between the desiccation experiment and the control yielded 163 differentially expressed genes. However, no common responses were found between the two treatments. The results suggest that E. tetraedra can acclimate to low temperatures due to the upregulation of genes involved in glucose accumulation. However, downregulation of the respiratory chain suggests that this earthworm does not tolerate freezing conditions. Under desiccation conditions, genes involved in cell protection from apoptosis and DNA repair were upregulated. In contrast, lipid metabolism was downregulated, presumably to conserve resources by reducing the rate at which they are consumed.

De novo transcriptome assemblies of red king crab (Paralithodes camtschaticus) and snow crab (Chionoecetes opilio) molting gland and eyestalk ganglia - Temperature effects on expression of molting and growth regulatory genes in adult red king crab.

Red king crab (Paralithodes camtschaticus) and snow crab (Chionoecetes opilio) are deep-sea crustaceans widely distributed in the North Pacific and Northwest Atlantic Oceans. These giant predators have invaded the Barents Sea over the past decades, and climate-driven temperature changes may influence their distribution and abundance in the sub-Arctic region. Molting and growth in crustaceans are strongly affected by temperature, but the underlying molecular mechanisms are little known, particularly in cold-water species. Here, we describe multiple regulatory factors in the two high-latitude crabs by developing de novo transcriptomes from the molting gland (Y-organ or YO) and eye stalk ganglia (ESG), in addition to the hepatopancreas and claw muscle of red king crab. The Halloween genes encoding the ecdysteroidogenic enzymes were expressed in YO, and the ESG contained multiple neuropeptides, including molt-inhibiting hormone (MIH), crustacean hyperglycemic hormone (CHH), and ion-transport peptide (ITP). Both crabs expressed a diversity of growth-related factors, such as mTOR, AKT, Rheb and AMPKα, and stress-responsive factors, including multiple heat shock proteins (HSPs). Temperature effects on the expression of key regulatory genes were quantified by qPCR in adult red king crab males kept at 4°C or 10°C for two weeks during intermolt. The Halloween genes tended to be upregulated in YO at high temperature, while the ecdysteroid receptor and several growth regulators showed tissue-specific responses to elevated temperature. Constitutive and heat-inducible HSPs were expressed in an inverse temperature-dependent manner, suggesting that adult red king crabs can acclimate to increased water temperatures.

Инклюзия против стресса: высшее образование для представителей коренных народов России

This article problematizes the organization of higher education for indigenous minorities, considering alternative strategies, namely segregation and inclusion, at the theoretical and empirical levels. Based on the analysis of publications by Russian and foreign researchers, representatives of indigenous peoples are presented as one of the categories, along with students from remote regions and from families with low socioeconomic status, whose opportunities for higher education are limited by a number of economic and social factors. The empirical study focuses on a group of Komi-Permyak (one of the indigenous ethnic groups of the Russian North) students studying in a large industrial city, Perm. The Department of Komi-Permyak Language and Literature of the Faculty of Philology at the Perm State University of Humanities and Pedagogy (PSUHP) provides professional training for teachers majoring in “Native (Komi-Permyak) Language and Literature and the Russian Language”. In addition to pedagogical disciplines, the curriculum includes a wide range of disciplines related to the linguistic aspects of the Komi-Permyak language, literature and regional studies. In the course of the interdisciplinary study, indicators of cortisol and anxiety levels -markers of stress response - were obtained. Their comparison with the same indicators of Russian students of other faculties of the same university (N=268) allowed us to conclude that Komi-Permyak students are adapted to the learn- © Козлова М.А., Козлов А.И., Корниенко Д.С., 2022 ing conditions. This fact distinguishes this group from students from other ethnic minorities of the Arctic and subarctic regions who study at other universities. The data provided by the department's administration on the composition of students indicate a low dropout rate of Komi-Permyaks, which indicates that the main factor of educational inequality in relation to this category of students has been overcome. The second stage of the study, carried out in a qualitative methodology (semi-structured interviews, N=9), analyzed aspects of the biographical situation, including migration experience, features of the organization of the educational process and individual strategies of education-al/career formation and building social ties within and outside the ethno-cultural community. Based on the barriers identified in the narratives of the informants and new opportunities for integration into a new sociocultural environment, the key factors of successful adaptation of indigenous students to learning conditions are reconstructed. On the basis of the obtained data, a conclusion is made about the adaptive and integrative potential of soft strategies of educational inclusion, which involve the creation of conditions that allow an individual to independently vary the degree of cultural closeness-openness and social inclusion-exclusion.

Trójdzielność młodszego dryasu obserwowana w rozwoju roślinności w otoczeniu torfowiska Żabieniec w środkowej Polsce

The Żabieniec mire is located in central Poland on the Łódź Highlands. Paleogeographical and paleoecological research have been being conducted there from a few decades. Organic sediments accumulated during the Eemian Interglacial, Vistulian Glaciation and Holocene reveal a continuous and detailed record of vegetation succession and environmental changes during these periods. Initially, a lake existed there and gyttja constitutes the sediment of the lower part of investigated core. Nowadays, there is still a small area of open water surrounded by mire. The high thickness of organic sediments, which is exceptional for old-glacial areas, enabled palaeoecological analyses and a detailed description of environmental history during the Late Glacial and Holocene. This article presents the pollen analysis record of vegetation development during the Younger Dryas, the last cold period of the Late Glacial. The chronology is based on radiocarbon dating made at the Gliwice Radiocarbon Laboratory of the Silesian University of Technology (Petera-Zganiacz et al. 2022). The course and proportions of dominating taxa and important “cold” species allowed for the division of the diagram into three phases. The first one lasted ca 900 years (50 cm of sediments) and shows a cooling, the development of cold-demanding plant communities, deforestation and an increase in trophy. The cooling of the climate was revealed in higher curves of Juniperus, Poaceae and Artemisia. The presence of pollen grains of light-demanding Hippophaë proved deforestation and dominance of open plant communities. Apart from aforementioned Artemisia, there grew steppe plants like Ephedra distachya and E. fragilis, Helianthemum and some herbs of identified: Chenopodiaceae, Anthemis type, Cichorioidae. Dwarf shrubs developed in wet habitats, namely Betula nana type and Salix polaris type. Dryas octopetala appeared on soil patches rich in calcium carbonate. The second phase lasted not longer than 230 years (50 cm of sediments) and shows preservation of cold-demanding vegetation and high trophy of the lake. This is the phase of stable ex-istence of cold-demanding species. A cold steppe dominated by Poaceae and Artemisia was enriched by many herbal plants represented in pollen types: Gypsophila repens type, Rumex acetosella, Bupleurum, Senecio type, Anthemis type, Cichorioidae. Thalictrum, Valeriana officinalis, Solanum dulcamara, Rumex acetosa developed next to dwarf shrubs of Betula nana and Salix. Exclusively in this phase, there appeared pollen type of Saxifraga hieraciifolia, a plant of calcareous habitats in subarctic regions and high moun-tains. At the same time, Juniperus and steppe elements (Helianthemum, Ephedra) decreased. High curves of Pediastrum and disappearance of spores of Isoëtes revealed high trophy of the lake during this phase. The third phase lasted ca 120 years (30 cm) and shows a decrease in cold- and light-demanding tundra and steppe taxa. There were only single pollen grains of Betula nana, Salix polaris type, Dryas octopetala. Meanwhile, Ephedra, Helianthemum and Gypsophila repens type disappeared. Trophy was clearly decreasing. Significant changes in trophy are suggested mainly based on the presence of Isoëtes, a plant of a very nutrient-poor water. The main changes in trophy are revealed mainly by high curve of oligotrophic Isoëtes found at the end of Allerød and then at the end of the Younger Dryas, while a phase of high tro-phy is marked by growing curves of some varieties of Pediastrum boryanum. Pollen analyses of some sites in Poland suggest that vegetation succession driven by macro-climatic features is significantly modified by local factors such as geomorphology, topography and physico-chemical properties of the ground/ habitat. Periods of cooling and warming at the be-ginning and end of the Younger Dryas have previously been defined in detail for the laminated sediments of Lake Gościąż. Microfacies, isotops and other paleoclimatic analyses done for that site indicated that the decrease in temperature at the beginning of the Younger Dryas and its in-crease at the end lasted, respectively, 180 and 70 years. They are shorter periods than phases of vegetation changes, because the reac-tion of plants and ecosystems development takes more time. Most Younger Dryas pollen diagrams in Poland can be divided into two parts. The first, older one reveals the development of tundra and cold steppe vegetation as a result of the climate cooling. The second shows the disappearance of cold-demanding species and tundra vegetation and the development of plants of warmer climate such as Typha latyfolia and Filipendula. Such a division can be found on diagrams from the Witów, Gościąż, Kaniewo, Łukie sites. Some pollen records, however, show stable curves during the entire Younger Dryas (Perespilno, Imiołki).

A multi-proxy study of Holocene environmental and climate change in the Pechora Delta

Abstract. The Arctic and subarctic regions have been the focus of a great deal of research during the recent years. Their high-latitude areas are thought to play a crucial role in climatic forcing and, thus, may be particularly sensitive to climate change. Arctic freshwater ecosystems are especially susceptible to the negative consequences of global environmental change drivers. Paleoclimatic investigations provide a better insight into the climate and environmental situation of certain regions and water objects in the past and help to predict their future changes, as well as to identify the development trends of the Earth s climate as a whole. The multy-proxy study of 96-cm long sediment core obtained in Lake Arcto-Pimberto (68 26.114 N, 053 32.311 E, the Pechora River delta, Nenets Autonomous Okrug) reflect regional paleoecological and climate changes in the north of the Eastern European plain over the last 6400 year. Based on the subfossil Cladocera, diatom and palynological analysis of the bottom sediment of the arctic lake Arkto-Pimberto, we received preliminary information on environmental and climatic changes, as well as on changes in vegetation character in the area around the water body.

Dental caries among 5-7 years old children in a Russian subarctic region

The aim of the study is to assess the prevalence and experience of dental caries among preschool children in a Russian Subarctic region. We performed a complex dental examination in 1232 randomly selected children aged 5-7 years using the World Health Organization (WHO) methodology (5th Edition) and standard dental forms. The overall prevalence of caries in primary dentition was 90.8%. Boys were more likely to have caries than girls (93.0% vs. 88.5%, p=0.007). Caries experience in deciduous teeth in the full sample was 6.43 with the average number of decayed, missing, and filled teeth being 4.67, 0.64 and 1.13, respectively. The prevalence of caries in permanent teeth was 5.2% with caries experience of 0.08. Decayed, missing, and filled teeth components were 0.06, 0 and 0.03, respectively. We observed high prevalence and experience of caries among 5-7 years old children in Arkhangelsk region. These findings exceed the national average and do not reach the WHO-2020 goals warranting urgent implementation of prevention strategies to improve dental health in this age group in Arctic and Subarctic Russia.

Geologic and geophysical exploration of the Russian Arctic in search for new oil and gas regions

Many specialists who studied Russian Arctic and subarctic regions consider that the latter should be rich in various minerals, for example, gold, tin, coal, kimberlites and, especially in oil and gas. The purpose of the article is to show the potential of regional geological and geophysical (remote sensing) methods for the study of tectonic and morphological features of the structure of the Arctic region subsoil allowing to conduct a regional study of potential resources of oil and gas in the Arctic shelf areas as well as in the mountainous or swampy Subarctic regions of Eastern Siberia inaccessible for other exploration methods (for example, seismic surveying). This article presents the results of the conducted scientific work, which together with other geological and geophysical methods will make it possible to carry out better aerospace studies of the tectonic structure of the Arctic region. In particular, the article introduces a block diagram of a computer software package for mathematical processing and the geological and geophysical interpretation of remote sensing data obtained as a result of measurements over the Arctic and Subarctic regions. The findings obtained on morphological (concentric) structures of the central type formed as a result of the occurrence of paleo-mantle plumes are compared with independent data on geological and geophysical sections of the earth's crust constructed in the zones where these structures are located. The obtained data on the oil and gas potential of some regions of the Arctic and Subarctic are compared with the results of forecasts made by other researchers and organizations.

BERRIES IN WINTER: A NATURAL HISTORY OF FRUIT RETENTION IN FOUR SPECIES ACROSS ALASKA

Plants with persistent fleshy fruits that last throughout fall and into winter and spring are an important source of nutrition for animals and people in boreal, subarctic, and arctic regions, but little information on fruit retention or loss is available for these regions. We evaluated fruit loss for four species across Alaska using data from our Winterberry community science network. Plants of Rosa acicularis Lindl., Viburnum edule (Michx.) Raf., Vaccinium vitis-idaea L., and Empetrum nigrum L. were monitored on a weekly basis throughout fall until snow cover and again after snow melt in 24 communities in six ecoregions in 2016–2020. Observers counted fruits and classified them into “unhealthy” (dried, rotten, or damaged) or “healthy”. Number of fruits lost per day (absolute loss rate) decreased over the course of the fall, but percent of fruits lost per day (relative loss rate) was constant for all species except E. nigrum, where it declined throughout the fall. Rates of loss were similar across ecoregions and climatic gradients, although for V. vitis-idaea the two most southern sites had the lowest relative loss rates and for E. nigrum the sites warmest in summer had the lowest loss rates. Fruit loss pulse events (>15% fruits lost in one week) were uncommon (<5% of weekly observations). At the time of persistent winter snow cover, plants retained 25–50% of fruits, with higher retention in more southern ecoregions. During winter, both relative fruit loss and absolute fruit loss rates dropped compared to fall, but in spring they rebounded to fall levels. Low proportions of unhealthy fruits in E. nigrum and V. vitis-idaea were in part due to rapid abscission of unhealthy fruits, while the other two species tended to retain unhealthy fruits. We estimate that vertebrate frugivores obtain 6–45 × as many fruits in fall as do decomposers / invertebrates. The higher loss rates during the snow-free seasons and constant rates of fruit loss for most of the focal species and locations suggest that longer falls and earlier fruit ripening will lead to lower fruit availability to animals in winter and spring.

Bryozoan carbonate skeletal geochemical composition in the White Sea compared with neighbouring seas

A fundamental question underlying skeletal mineral secretion in marine invertebrates is the extent to which the physico-chemical parameters of seawater (e.g., salinity, temperature) and animal physiology influence their skeletal mineralogy and chemistry. Groups with more complex mineralogies, such as bryozoans, have the ability to actively control their own skeletal composition in response to environmental conditions and could be considered indicators of global environmental change. Thus, this study aims to reveal how the unique environmental conditions of low salinity (circa 24–26), prominent seasonality and semi-isolation of the White Sea (WS) subarctic region caused by the last glaciation (12,000 ya) affect the carbonate skeletal geochemical composition of bryozoans. X-ray diffraction analysis of 27 bryozoan taxa (92 specimens) revealed a completely monomineral calcite composition of skeletons with a mean value of 6.9 ± 1.8 mol% MgCO3 and moderate variability at the species and family levels. Most specimens (43.5%) precipitated skeletal magnesium within the range of 7–8 mol% MgCO3. Regional analysis of the mineralogical profile of the White Sea bryozoans shows that they differ statistically from bryozoan species living in the neighbouring Arctic and temperate Scotland regions in terms of magnesium content in calcite (approximately 7 mol% MgCO3 in the White Sea versus 5 mol% MgCO3 in other regions). We suggest that the effect of low salinity on magnesium content was compensated by relatively high summer temperature causing rapid growth and calcification and possibly resulted in the increased Mg contents in the White Sea (WS) bryozoans. However, on a local scale (between sampling locations), the influence of temperature and salinity could be excluded as a source of observed intraspecific variability. The concentration of MgCO3 in skeletons of the studied bryozoans is controlled by other environmental variables or is species-specific and depends on the physiological processes of the organisms.

Plant Organic Matter in Palsa and Khasyrei Type Mires: Direct Observations in West Siberian Sub-Arctic

This article presents the first results of long-term direct measurements of a few major components of carbon cycle in permafrost mire landforms in the sub-Arctic region of Western Siberia, Russia. It reveals the main features of geographical distribution of plant organic matter, including both the above-ground and below-ground fractions of live biomass, the biomass of dead roots (mortmass), and net primary production (NPP) in peat-accumulating flat palsa mires and in “khasyrei”—ecosystems of drained lakes in thermokarst depression on epigenetic permafrost. The study based on original methods of direct field measurements elaborated by authors for northern peatlands. In northern taiga, the NPP of palsa mires was found in the range of 300–580 g m−2 yr−1 and an average biomass of 1800 g m−2; in khasyrei, it accounts for 1100 g m−2 yr−1 and 2000 g m−2 of NPP and live biomass, respectively. In forest tundra, the live biomass of palsa mires was found in the range of 1000–1800 g m−2, and in khasyrei it was 2300 g m−2. The NPP of palsa mires were in the range of 400–560 g m−2 yr−1, and in khasyrei it was 800 g m−2 yr−1. Overall, we conclude that the south–north climatic gradient in Western Siberia is the main driver of plant organic matter accumulation. It was found different across mire ecosystems of the same types but located in different bioclimatic regions.

Cyanobacterial Diversity of the Northern Polar Ural Mountains

This study provides new results from an inventory of cyanobacterial species from the Northern Polar Ural Mountains. The article also compiles all existing published data on the cyanobacterial diversity of the region. This ecoregion is located in a unique geographical position in the transition between the sub-Arctic and low Arctic zones and heterogeneous natural conditions. Likely, the unexplored biodiversity of this area’s terrestrial cyanobacteria is high. In total, 52 localities were studied, with 232 samples collected. Cyanobacterial samples were studied under a light microscope. Species were identified based on morphological characteristics only. A total of 93 species of cyanobacteria were identified in different habitats; 70 species were found on wet rocks, 35 on the shores of water bodies, 27 in slow streams, and 21 on waterfalls. In total, 37 species are reported as part of the Ural flora for the first time, while three species (Chroococcus ercegovicii, Gloeocapsopsis cyanea, Gloeothece tepidariorum) were detected in Russian territory for the first time. The composition of the cyanobacterial flora of the Polar Urals was compared with the flora of the nearby Arctic and sub-Arctic regions. According to the Sorensen similarity index, the Polar Urals’ flora is more like the flora of Nenets Autonomous Okrug.

Variability of Microbial Communities in Two Long-Term Ice-Covered Freshwater Lakes in the Subarctic Region of Yakutia, Russia.

Although under-ice microbial communities are subject to a cold environment, low concentrations of nutrients, and a lack of light, they nevertheless take an active part in biogeochemical cycles. However, we still lack an understanding of how high their diversity is and how these communities are distributed during the long-term ice-cover period. Here, we assessed for the first time the composition and distribution of microbial communities during the ice-cover period in two subarctic lakes (Labynkyr and Vorota) located in the area of the lowest temperature in the Northern Hemisphere. The diversity distribution and abundance of main bacterial taxa as well as the composition of microalgae varied by time and habitat. The 16S rRNA gene sequencing method revealed, in general, a high diversity of bacterial communities where Proteobacteria (~ 45%) and Actinobacteria (~ 21%) prevailed. There were significant differences between the communities of the lakes: Chthoniobacteraceae, Moraxellaceae, and Pirellulaceae were abundant in Lake Labynkyr, while Cyanobiaceae, Oligoflexales, Ilumatobacteraceae, and Methylacidiphilaceae were more abundant in Lake Vorota. The most abundant families were evenly distributed in April, May, and June their contribution was different in different habitats. In April, Moraxellaceae and Ilumatobacteraceae were the most abundant in the water column, while Sphingomonadaceae was abundant both in water column and on the ice bottom. In May, the abundance of Comamonadaceae increased and reached the maximum in June, while Cyanobiaceae, Oxalobacteraceae, and Pirellulaceae followed. We found a correlation of the structure of bacterial communities with snow thickness, pH, Nmin concentration, and conductivity. We isolated psychrophilic heterotrophic bacteria both from dominating and minor taxa of the communities studied. This allowed for specifying their ecological function in the under-ice communities. These findings will advance our knowledge of the under-ice microbial life.

Siberian Ecosystems as Drivers of Cryospheric Climate Feedbacks in the Terrestrial Arctic

Climate warming is altering the persistence, timing, and distribution of permafrost and snow cover across the terrestrial northern hemisphere. These cryospheric changes have numerous consequences, not least of which are positive climate feedbacks associated with lowered albedo related to declining snow cover, and greenhouse gas emissions from permafrost thaw. Given the large land areas affected, these feedbacks have the potential to impact climate on a global scale. Understanding the magnitudes and rates of changes in permafrost and snow cover is therefore integral for process understanding and quantification of climate change. However, while permafrost and snow cover are largely controlled by climate, their distributions and climate impacts are influenced by numerous interrelated ecosystem processes that also respond to climate and are highly heterogeneous in space and time. In this perspective we highlight ongoing and emerging changes in ecosystem processes that mediate how permafrost and snow cover interact with climate. We focus on larch forests in northeastern Siberia, which are expansive, ecologically unique, and studied less than other Arctic and subarctic regions. Emerging fire regime changes coupled with high ground ice have the potential to foster rapid regional changes in vegetation and permafrost thaw, with important climate feedback implications.

High-Quality Complete Genome Resource of Pathogenic Bacterium Pectobacterium atrosepticum Strain Green1 Isolated from Potato (Solanum tuberosum L.) in Greenland.

Pectobacterium atrosepticum is a narrow-host-range, pectinolytic, plant-pathogenic bacterium causing blackleg of potato (Solanum tuberosum L.) worldwide. Till present, several P. atrosepticum genomes have been sequenced and characterized in detail; however, all of these genomes have come from P. atrosepticum isolates from plants grown in temperate zones, not from hosts cultivated under different climatic conditions. Herewith, we present the first complete, high-quality genome of the P. atrosepticum strain Green1 isolated from potato plants grown under a subarctic climate in Greenland. The genome of P. atrosepticum strain Green1 consists of one chromosome of 4,959,719 bp, with a GC content of 51% and no plasmids. The genome contains 4,531 annotated features, including 4,179 protein-coding genes, 22 ribosomal RNA genes, 70 transfer RNA genes, 8 noncoding RNA genes, 2 CRISPRs, and 126 pseudogenes. We believe that the information in this first high-quality, complete, closed genome of P. atrosepticum strains isolated from host plants grown in a subarctic agricultural region will provide resources for comparative genomic studies and for analyses targeting climatic adaptation and ecological fitness mechanisms present in P. atrosepticum.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Influence of systemic inflammation predictors on the premature labor of hiv-infected women living in Subarctic region

The goal is to conduct a comparative analysis of the characteristics of blood counts of pregnant women with HIV living in the subarctic climatic zone of the Khanty-Mansiysk District, as predictors of a systemic inflammatory reaction on the background of infection and pregnancy complicated by preterm delivery.Material and methods. A retrospective analysis of 78 stories of pregnant women with HIV (main group II) was carried out, in 2016–2018. observed in one antenatal clinic in the city of Surgut. Control group (I) comprised 20 histories of pregnant women without HIV. Clinical-anamnestic and blood parameters were compared, including indicators of T-helpers, T-suppressors and viral load, leukocyte intoxication indices, hemoglobin, erythrocytes and platelets by trimesters of pregnancy. The material was processed using the Statistica-10 software system. The critical level of statistical significance was taken at p&lt;0,05.Results. A comparative analysis of blood counts of pregnant women living in the subarctic region showed a relationship between the preterm labor of patients with HIV with a progressive decrease in the T-cell level of immunity, an increase in the level of lymphocytes and leukocyte blood indices, a decrease of hemoglobin, erythrocytes, platelets, against the background of persisting viral load for the remainder of pregnancy. A decrease of T-lymphocyte counts indicates the development of a systemic inflammatory response on the background of HIV infection, depletion of the immune defense organs and the progression of the disease, while a low level of CD4 lymphocytes stimulates the activation of granulocytes in the blood and indicates further depletion of T-lymphocytes. Activation of a systemic inflammatory response that promotes the release of inflammatory mediators and prostaglandins and, with a high probability, underlies the mechanisms of rejection of the fetus and placenta and the spontaneous preterm labor. The comorbid background of pregnant women with HIV and preterm labor is associated with low adherence to HAART therapy and high detectable viral load throughout gestation.

Technical note: Quality assessment of ozone reanalysis products and gap-filling over subarctic Europe for vegetation risk mapping

Abstract. We assess the quality of regional and global ozone reanalysis data for vegetation modeling and ozone (O3) risk mapping over subarctic Europe where monitoring is sparse. Reanalysis data can be subject to systematic errors originating from, for example, quality of assimilated data, distribution and strength of precursor sources, incomprehensive atmospheric chemistry or land–atmosphere exchange, and spatiotemporal resolution. Here, we evaluate two selected global products and one regional ozone reanalysis product. Our analysis suggests that global reanalysis products do not reproduce observed ground-level ozone well in the subarctic region. Only the Copernicus Atmosphere Monitoring Service Regional Air Quality (CAMSRAQ) reanalysis ensemble sufficiently captures the observed seasonal cycle. We also compute the root mean square error (RMSE) by season. The RMSE variation between (2.6–6.6) ppb suggests inherent challenges even for the best reanalysis product (CAMSRAQ). O3 concentrations in the subarctic region are systematically underestimated by (2–6) ppb compared to the ground-level background ozone concentrations derived from observations. Spatial patterns indicate a systematical underestimation of ozone abundance by the global reanalysis products on the west coast of northern Fennoscandia. Furthermore, we explore the suitability of CAMSRAQ for gap-filling at one site in northern Norway with a long-term record but not belonging to the observational network. We devise a reconstruction method based on Reynolds decomposition and adhere to recommendations by the United Nations Economic Commission for Europe (UNECE) Long-Range Transboundary Air Pollution (LRTAP) convention. The thus reconstructed data for 2 weeks in July 2018 are compared with CAMSRAQ evaluated at the nearest-neighbor grid point. Our reconstruction method's performance (76 % accuracy) is comparable with CAMSRAQ (80 % accuracy), but diurnal extremes are underestimated by both.

Changing winter diet of Thick-billed Murres (Uria lomvia) in southwest Greenland, 1990s versus 2010s

Southwest Greenland constitutes an internationally important wintering area for seabirds, including Thick-billed Murres (Uria lomvia (Linnaeus, 1758)), but their prey may be affected by the general warming of this sub-Arctic region. We compared murre diet collected in winter in the 1990s and in the 2010s around Nuuk, Greenland. Fish made up 36% of the diet (wet mass) and crustaceans 63% in the 1990s, changing to 22% and 78% in the 2010s, respectively. Capelin (Mallotus villosus (Müller, 1776)) was the dominant fish species, and the smaller contribution in the 2010s coincided with declining densities of capelin around Nuuk. The crustaceans were dominated by two krill species (Meganyctiphanes norvegica (M. Sars, 1857) and Thysanoessa inermis (Krøyer, 1846)). However, M. norvegica was only important in the 2010s (51% wet mass), while T. inermis was dominating the 1990s with 62% wet mass and only 23% in the 2010s. The dominance of M. norvegica in the 2010s confirmed our expectations of a gradual “borealization” of this region due to the generally warming sub-Arctic. The smaller contribution of fish in the diet may also support the hypothesis of deteriorating winter conditions for murres. Apart from the diet, plastic was found in 15% of the birds and 53% had parasitic nematodes.

Dynamics of Nutrients and Colored Dissolved Organic Matter Absorption in a Wetland-Influenced Subarctic Coastal Region of Northeastern Japan: Contributions From Mariculture and Eelgrass Meadows

Coastal oceans interacting with terrestrial ecosystems play an important role in biogeochemical cycles. It is therefore essential to research land–ocean interactions for further understanding of the processes influencing nutrients dynamics in coastal areas. We investigated the seasonal and spatial distribution of nutrient concentrations and light absorption coefficients of colored dissolved organic matter (CDOM), non-algal particles (NAP), and phytoplankton in a wetland-influenced river–eelgrass meadows–coastal waters continuum in the protected and semi-enclosed coastal sea of Akkeshi-ko estuary (AKE) and Akkeshi Bay (AB), Japan from April 2014 to February 2015. The mixing dilution lines of the CDOM absorption coefficient at 355 nm [aCDOM(355)] relative to salinity predicted by two end-members between freshwater and coastal water showed conservative mixing in AB. Silicate concentrations were significantly correlated with salinity and aCDOM(355) in AB in each month except for December 2014. These results suggest that silicate and CDOM in AB primarily originates from wetland-influenced river discharge. However, samples collected from the eelgrass meadows of AKE, where mariculture is developed, showed non-conservative mixing of silicate concentrations and aCDOM(355) with salinity except for June 2014. Elevated phosphate concentrations, probably released from sediments, were also found in the eelgrass meadows of AKE, especially during summer. These results suggest that the metabolic activities of mariculture and seagrass ecosystem significantly contribute to the nutrient cycles and CDOM absorption in AKE and to the distinct water-mass systems inside and outside AKE. The relative absorption properties of NAP [aNAP(443)], phytoplankton [aph(443)], and aCDOM(443) showed that CDOM is the main factor affecting the light distribution in AKE. However, the relative absorption properties varied seasonally in AB because of spring and autumn phytoplankton blooms and ice cover during winter. Significant relationships were observed between the Secchi disk depth (ZSD), aNAP(443), and aCDOM(443). Chl a concentration and aph(443) were not good indicators for predicting ZSD in our study region. These results suggest that incorporating inherent optical properties and CDOM from mariculture and seagrass ecosystem into ecosystem models could improve predictions of light distribution along the freshwater–eelgrass–coastal waters continuum in optically complex coastal waters.

Possible future scenarios for two major Arctic Gateways connecting Subarctic and Arctic marine systems: I. Climate and physical–chemical oceanography

AbstractWe review recent trends and projected future physical and chemical changes under climate change in transition zones between Arctic and Subarctic regions with a focus on the two major inflow gateways to the Arctic, one in the Pacific (i.e. Bering Sea, Bering Strait, and the Chukchi Sea) and the other in the Atlantic (i.e. Fram Strait and the Barents Sea). Sea-ice coverage in the gateways has been disappearing during the last few decades. Projected higher air and sea temperatures in these gateways in the future will further reduce sea ice, and cause its later formation and earlier retreat. An intensification of the hydrological cycle will result in less snow, more rain, and increased river runoff. Ocean temperatures are projected to increase, leading to higher heat fluxes through the gateways. Increased upwelling at the Arctic continental shelf is expected as sea ice retreats. The pH of the water will decline as more atmospheric CO2 is absorbed. Long-term surface nutrient levels in the gateways will likely decrease due to increased stratification and reduced vertical mixing. Some effects of these environmental changes on humans in Arctic coastal communities are also presented.