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1.
Science ; 368(6498): 1495-1499, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32587022

RESUMO

Although sled dogs are one of the most specialized groups of dogs, their origin and evolution has received much less attention than many other dog groups. We applied a genomic approach to investigate their spatiotemporal emergence by sequencing the genomes of 10 modern Greenland sled dogs, an ~9500-year-old Siberian dog associated with archaeological evidence for sled technology, and an ~33,000-year-old Siberian wolf. We found noteworthy genetic similarity between the ancient dog and modern sled dogs. We detected gene flow from Pleistocene Siberian wolves, but not modern American wolves, to present-day sled dogs. The results indicate that the major ancestry of modern sled dogs traces back to Siberia, where sled dog-specific haplotypes of genes that potentially relate to Arctic adaptation were established by 9500 years ago.


Assuntos
Adaptação Fisiológica/genética , Cães/genética , Animais , Apolipoproteínas/genética , Regiões Árticas , Ácidos Graxos/metabolismo , Genoma , Groenlândia , Haplótipos , Proteínas de Transporte da Membrana Mitocondrial/genética , Seleção Artificial , Análise de Sequência de DNA , Sibéria , Triglicerídeos/metabolismo , Lobos/genética
2.
Environ Sci Pollut Res Int ; 27(21): 27111-27123, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32394255

RESUMO

Background and anomalous rare earth element (RЕЕ) concentrations in poplar (Populus spp.) leaves in urban areas of Siberia, Russian Far East, and Kazakhstan were determined. Regions with the highest RЕЕ levels were identified. Ratios of light to middle RЕЕs are geochemical indicators of the impacts of oil refining and mining. Airborne dust transport by prevailing winds from ash and slag dumps of power plants and industrial sites, and alluvial terraces control the REE distribution in cities.


Assuntos
Metais Terras Raras/análise , Populus , Cidades , Extremo Oriente , Cazaquistão , Folhas de Planta/química , Federação Russa , Sibéria
3.
Nature ; 581(7808): 294-298, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433620

RESUMO

Warming surface temperatures have driven a substantial reduction in the extent and duration of Northern Hemisphere snow cover1-3. These changes in snow cover affect Earth's climate system via the surface energy budget, and influence freshwater resources across a large proportion of the Northern Hemisphere4-6. In contrast to snow extent, reliable quantitative knowledge on seasonal snow mass and its trend is lacking7-9. Here we use the new GlobSnow 3.0 dataset to show that the 1980-2018 annual maximum snow mass in the Northern Hemisphere was, on average, 3,062 ± 35 billion tonnes (gigatonnes). Our quantification is for March (the month that most closely corresponds to peak snow mass), covers non-alpine regions above 40° N and, crucially, includes a bias correction based on in-field snow observations. We compare our GlobSnow 3.0 estimates with three independent estimates of snow mass, each with and without the bias correction. Across the four datasets, the bias correction decreased the range from 2,433-3,380 gigatonnes (mean 2,867) to 2,846-3,062 gigatonnes (mean 2,938)-a reduction in uncertainty from 33% to 7.4%. On the basis of our bias-corrected GlobSnow 3.0 estimates, we find different continental trends over the 39-year satellite record. For example, snow mass decreased by 46 gigatonnes per decade across North America but had a negligible trend across Eurasia; both continents exhibit high regional variability. Our results enable a better estimation of the role of seasonal snow mass in Earth's energy, water and carbon budgets.


Assuntos
Mapeamento Geográfico , Neve , Análise Espaço-Temporal , Viés , Carbono/análise , Planeta Terra , Aquecimento Global/estatística & dados numéricos , História do Século XX , História do Século XXI , América do Norte , Estações do Ano , Sibéria , Neve/química , Temperatura , Incerteza , Água/análise
5.
Zootaxa ; 4758(2): zootaxa.4758.2.8, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32230147

RESUMO

This paper revises the existing system of formal classification by Vialov and Vasilenko for fossil plants involving insect feeding and oviposition. The classification of these fossil traces has been amended and supplemented in accordance with the requirements of the International Code of Zoological Nomenclature. The following nomenclatural combinations are made: Insectophagichnata (Vialov) Enushchenko and Frolov, comb. et stat. (classis) nov., Phagolignichnidina (Vialov) Enushchenko and Frolov, comb. et stat. (subordo) nov., Phagophytichnidina (Vialov) Enushchenko and Frolov, comb. et stat. (subordo) nov. Fossil traces of these interactions were found and illustrated for Mesozoic insects and leafes of Ginkgo tapkensis from Middle Jurassic sediments of the Irkutsk Coal Basin in Eastern Siberia, Russia. The examined traces consist of ovipositions (traces of insect egg laying), galls (traces of insect caused teratologies) and epidermal punctures (traces of piercing and sucking). The following ichnotaxa are described and illustrated: Paleoovidinae Enushchenko and А. Frolov, ichnosubfam. nov., Paleoexoovoidinae Enushchenko and Frolov, ichnosubfam. nov., Sugophytichninae Enushchenko and А. Frolov, ichnosubfam. nov., Sugophytichnida pertusura Enushchenko and Frolov, ichnogen. et ichnospec. nov., Paleoovidus vasilenkoi Enushchenko and А. Frolov, ichnospec. nov., Paleoexoovoida ovoidea Enushchenko and А. Frolov, ichnogen. et ichnosp. nov., Paleogallus vialovi Enushchenko and Frolov, ichnospec. nov. Punctures of the leaf epidermis probably belong Mesozoic cicadas of the Palaeontini, which dominate the adjacent strata of the studied location. The extremely low occurrence of interaction between insects and plants in these Jurassic deposits of Eastern Siberia have ichnotaxonomic importance for understanding the functioning of Jurassic terrestrial paleoecosystems.


Assuntos
Fósseis , Insetos , Animais , Feminino , Folhas de Planta , Federação Russa , Sibéria
6.
Environ Sci Pollut Res Int ; 27(18): 22400-22413, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32314286

RESUMO

Forest surveys were conducted in 2015-2018 on 12 sample plots (SPs), located in different districts of the city of Bratsk, a large industrial center of Eastern Siberia. The ecological state of natural forests preserved within the city's territory was estimated by a set parameters of pine (Pinus sylvestris L.) trees, understory vegetation, moss-and-lichen cover, and soil. Significant changes in the parameters caused by technogenic pollution and a high recreational load on the soil cover have been revealed. The high level of technogenic pollution of urban forests is evidenced by the accumulation of pollutants (sulfur, heavy metals, PAH) in the needles of pine trees and soil horizons, changes in the ratios of elements-pollutants and elements-nutrients in plants and soils, shift in the acid-base balance of the soil solution to alkalinity. A high recreational load on urban forest soils is indicated by many negative changes: a decrease in the thickness of the forest litter or its complete destruction; violation of the natural structure of the upper horizons due to increase in physical clay content, stony content, and anthropogenic inclusions; significant increase in soil density, and decrease in humidity, porosity, and aeration. The impact of a complex of negative factors also leads to a decrease in the species diversity of the understory vegetation, mosses, lichens, and an increase in the number of ruderal species in the herbaceous vegetation. The biggest negative changes in the parameters of forest ecosystems have been found in Tsentralny district of the city, located in close proximity (from 2 to 8 km) to a large aluminum smelter and timber industry complex. Less-pronounced negative changes in parameters were found in samples taken in the Padunsky district, located 25 km from the emission source, and the smallest changes in the parameters were found in Pravoberezhny district, 45 km away from the emission sources. The main recommendations for improving the condition of forests in all areas of the city are as follows: planning a road-path network, restoring the fertile soil layer, sodding open areas of soil with herbaceous vegetation, and selecting an assortment of trees and shrub plants that are resistant to industrial pollution and recreational stress.


Assuntos
Ecossistema , Monitoramento Ambiental , Cidades , Florestas , Federação Russa , Sibéria , Solo , Árvores
7.
PLoS One ; 15(4): e0230284, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294095

RESUMO

Large, old and heterogenous lake systems are valuable sources of biodiversity. The analysis of current spatial variability within such lakes increases our understanding of the origin and establishment of biodiversity. The environmental sensitivity and the high taxonomic richness of diatoms make them ideal organisms to investigate intra-lake variability. We investigated modern intra-lake diatom diversity in the large and old sub-arctic Lake Bolshoe Toko in Siberia. Our study uses diatom-specific metabarcoding, applying a short rbcL marker combined with next-generation sequencing and morphological identification to analyse the diatom diversity in modern sediment samples of 17 intra-lake sites. We analysed abundance-based compositional taxonomic diversity and generic phylogenetic diversity to investigate the relationship of diatom diversity changes with water depth. The two approaches show differences in taxonomic identification and alpha diversity, revealing a generally higher diversity with the genetic approach. With respect to beta diversity and ordination analyses, both approaches result in similar patterns. Water depth or related lake environmental conditions are significant factors influencing intra-lake diatom patterns, showing many significant negative correlations between alpha and beta diversity and water depth. Further, one near-shore and two lagoon lake sites characterized by low (0-10m) and medium (10-30m) water depth are unusual with unique taxonomic compositions. At deeper (>30m) water sites we identified strongest phylogenetic clustering in Aulacoseira, but generally much less in Staurosira, which supports that water depth is a strong environmental filter on the Aulacoseira communities. Our study demonstrates the utility of combining analyses of genetic and morphological as well as phylogenetic diversity to decipher compositional and generic phylogenetic patterns, which are relevant in understanding intra-lake heterogeneity as a source of biodiversity in the sub-arctic glacial Lake Bolshoe Toko.


Assuntos
Biodiversidade , Diatomáceas , Lagos/microbiologia , Filogenia , Diatomáceas/classificação , Diatomáceas/genética , Sibéria
8.
Environ Monit Assess ; 192(4): 215, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32140832

RESUMO

In order to evaluate the level of atmospheric pollution in the north of Western Siberia, we studied the composition of urban snow in the vicinity of the Tazovsky settlement as well as in the area of Zapolyarnoye-the largest natural gas field in Russia in terms of a total extraction volume. Our results indicate that anthropogenic activities have caused an increase in electric conductivity and pH values of meltwaters. Concentrations of dissolved and particulate forms of trace elements (Fe, Mn, Ni, Cr, Cu, Pb, Zn, and Cd) were determined using atomic absorption spectroscopy. Dissolved forms of Cd, Zn, and Mn and particulate forms of Cu, Fe, and Ni prevailed in meltwaters of background territories. Human-affected territories were characterized by a predominance of particulate forms of trace elements (except Cd), which indicated increased dust deposition rates. For Cu, Mn, and Fe, mean values of contamination factor (CF) exceeded background levels by 4.4, 4.7, and 6.6 times, respectively. At some sampling sites, concentrations of trace elements exceeded background levels by 10-111 times. The concentration of Zn in our study area was higher than those in other oil and gas fields located in polar and boreal regions. The Cd concentration in the vicinity of the Tazovsky settlement was higher than those in other cities of Western Siberia. The data obtained in the present study on concentrations of soluble and particulate forms of trace elements in snow will be valuable for environmental protection in Russia's Arctic territory.


Assuntos
Monitoramento Ambiental , Neve , Oligoelementos , Cidades , Humanos , Federação Russa , Sibéria
9.
Sci Total Environ ; 720: 137590, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32143049

RESUMO

A shift from temperature-limited to water-limited tree performance is occurring at around 60°N latitude across the circumboreal biome, in concord with current warming trends. This shift is likely to induce extensive vegetation changes and forest die-back, and also to exacerbate biotic outbreaks and wildfires, affecting the global carbon budget. We used carbon isotope discrimination (Δ13C) in tree rings to analyze the long-term physiological responses of five representative species that coexist in the middle taiga of Western Siberia, including dark-needled, drought-susceptible (Abies sibirica, Picea obovata, Pinus sibirica) and light-needled, drought-resistant (Larix sibirica, Pinus sylvestris) conifers. We hypothesized that droughts are differentially imprinted in dark and light conifers, with stronger Δ13C-responsiveness in the latter reflecting a more conservative water use. We found similar Δ13C-climate relationships related to the moisture regime of the summer season across species, indicating shared drought responses; however, divergent intrinsic water-use efficiency (WUEi) trajectories from 1950 to 2013 were observed for pines (increasing by ca. 10%) and other conifers (increasing by ca. 25%). These contrasting patterns suggested the passive and active stomatal regulation of gas exchange in these trees, respectively, and led us to discard our initial hypothesis. Discriminant analysis shed light on the climate characteristics responsible for such differential behavior, with years having lower temperatures from May through August (3 °C colder on average) being responsible for reduced pine WUEi. This finding may be related to the higher plasticity of phenology of pines and the greater susceptibility of fir and spruce to cold damage and heat shock during the early growing season (late April-May). Together with recent negative growth trends and increasing ring-width vs. Δ13C coupling, these results indicate the greater susceptibility of spruce and fir, compared with pines and larch, in boreal ecosystems when transitioning from a temperature- to a moisture-sensitive regime.


Assuntos
Secas , Traqueófitas , Florestas , Sibéria , Taiga , Água
10.
PLoS One ; 15(2): e0228610, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32074114

RESUMO

Salamanders (Caudata) are one of the three modern groups of amphibians known from the Middle Jurassic. The early stages of evolution of these amphibians are still poorly known, especially for stem taxa of Jurassic age. A new small-sized stem salamander, Egoria malashichevi gen. et sp. nov., from the Middle Jurassic (Bathonian) Itat Formation of the Berezovsk Quarry locality in Western Siberia, Russia, is described on the basis of isolated vertebrae, including an atlas centrum and a fragmentary trunk vertebra centrum previously referred to an undescribed salamander taxon ("Berezovsk salamander A"). The new taxon is diagnosed by the following unique combination of vertebral characters: atlantal anterior cotyles with elliptical anterior outline, located at an angle of approximately 135-137 degrees to each other; wide posterior portion of the atlantal centrum; ossified portion of the intercotylar tubercle represented by dorsal and ventral lips; absence of a deep depression on the ventral surface of the atlantal centrum; absence of pronounced ventrolateral ridges on the atlas; absence of spinal nerve foramina; presence of a pitted texture on the ventral and lateral surfaces of the centra and lateral surfaces neural arch pedicels; presence of a short atlantal neural arch with its anterior border situated behind the level of the anterior cotyles; short trunk vertebrae; and upper transverse process (= diapophysis) larger than lower transverse process (= parapophysis) on the trunk vertebrae; notochordal canal opens in the upper half of the cotyle (= the lower portion of the centrum is more massive and less compact than the upper portion). The microanatomical organization of the atlas and trunk vertebrae is characterized by the presence of inner cancellous endochondral bone. The small body size (about 180-215 mm) of Egoria malashichevi gen. et sp. nov. indicates that that not all stem salamanders were large neotenic forms (up to 550-600 mm in Urupia and Marmorerpeton) and hints at a broader ecological role for stem salamanders.


Assuntos
Fósseis/anatomia & histologia , Urodelos/anatomia & histologia , Animais , Osso e Ossos/anatomia & histologia , Sibéria , Urodelos/classificação
11.
Sci Total Environ ; 711: 134851, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32000328

RESUMO

One of the effects of climate change on boreal forest will be more frequent forest wildfires and permafrost thawing. These will increase the availability of soil organic matter (SOM) for microorganisms, change the ground vegetation composition and ultimately affect the emissions of biogenic volatile organic compounds (BVOCs), which impact atmospheric chemistry and climate. BVOC emissions from boreal forest floor have been little characterized in southern boreal region, and even less so in permafrost soil, which underlies most of the northern boreal region. Here, we report the long-term effects of wildfire on forest floor BVOC emission rates along a wildfire chronosequence in a Larix gmelinii forest in central Siberia. We determined forest floor BVOC emissions from forests exposed to wildfire 1, 23 and > 100 years ago. We studied how forest wildfires and the subsequent succession of ground vegetation, as well as changes in the availability of SOM along with the deepened and recovered active layer, influence BVOC emission rates. The forest floor acted as source of a large number of BVOCs in all forest age classes. Monoterpenes were the most abundant BVOC group in all age classes. The total BVOC emission rates measured from the 23- and >100-year-old areas were ca. 2.6 times higher than the emissions from the 1-year-old area. Lower emissions were related to a decrease in plant coverage and microbial decomposition of SOM after wildfire. Our results showed that forest wildfires play an important indirect role in regulating the amount and composition of BVOC emissions from post-fire originated boreal forest floor. This could have a substantial effect on BVOC emissions if the frequency of forest wildfires increases in the future as a result of climate warming.


Assuntos
Pergelissolo , Incêndios Florestais , Sibéria , Taiga , Compostos Orgânicos Voláteis
12.
Environ Pollut ; 259: 113814, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32023784

RESUMO

Mercury (Hg) loading in Lake Baikal, a UNESCO world heritage site, is growing and poses a serious health concern to the lake's ecosystem due to the ability of Hg to transform into a toxic form, known as methylmercury (MeHg). Monitoring of Hg into Lake Baikal is spatially and temporally sparse, highlighting the need for insights into historic Hg loading. This study reports measurements of Hg concentrations from water collected in August 2013 and 2014 from across Lake Baikal and its main inflow, the Selenga River basin (Russia, Mongolia). We also report historic Hg contamination using sediment cores taken from the south and north basins of Lake Baikal, and a shallow lake in the Selenga Delta. Field measurements from August 2013 and 2014 show high Hg concentrations in the Selenga Delta and river waters, in comparison to pelagic lake waters. Sediment cores from Lake Baikal show that Hg enrichment commenced first in the south basin in the late-19th century, and then in the north basin in the mid-20th century. Hg flux was also 20-fold greater in the south basin compared to the north basin sediments. Hg enrichment was greatest in the Selenga Delta shallow lake (Enrichment Ratio (ER) = 2.3 in 1994 CE), with enrichment occurring in the mid-to late-20th century. Local sources of Hg are predominantly from gold mining along the Selenga River, which have been expanding over the last few decades. More recently, another source is atmospheric deposition from industrial activity in Asia, due to rapid economic growth across the region since the 1980s. As Hg can bioaccumulate and biomagnify through trophic levels to Baikal's top consumer, the world's only truly freshwater seal (Pusa sibirica), it is vital that Hg input at Lake Baikal and within its catchment is monitored and controlled.


Assuntos
Monitoramento Ambiental , Mercúrio , Poluentes Químicos da Água , Ásia , Ecossistema , Sedimentos Geológicos , Lagos , Mongólia , Rios , Federação Russa , Sibéria
13.
Proc Natl Acad Sci U S A ; 117(6): 2879-2885, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-31988114

RESUMO

Neanderthals were once widespread across Europe and western Asia. They also penetrated into the Altai Mountains of southern Siberia, but the geographical origin of these populations and the timing of their dispersal have remained elusive. Here we describe an archaeological assemblage from Chagyrskaya Cave, situated in the Altai foothills, where around 90,000 Middle Paleolithic artifacts and 74 Neanderthal remains have been recovered from deposits dating to between 59 and 49 thousand years ago (age range at 95.4% probability). Environmental reconstructions suggest that the Chagyrskaya hominins were adapted to the dry steppe and hunted bison. Their distinctive toolkit closely resembles Micoquian assemblages from central and eastern Europe, including the northern Caucasus, more than 3,000 kilometers to the west of Chagyrskaya Cave. At other Altai sites, evidence of earlier Neanderthal populations lacking associated Micoquian-like artifacts implies two or more Neanderthal incursions into this region. We identify eastern Europe as the most probable ancestral source region for the Chagyrskaya toolmakers, supported by DNA results linking the Neanderthal remains with populations in northern Croatia and the northern Caucasus, and providing a rare example of a long-distance, intercontinental population movement associated with a distinctive Paleolithic toolkit.


Assuntos
Arqueologia , Homem de Neandertal/genética , Animais , Cavernas , Fósseis/história , História Antiga , Sibéria
14.
PLoS One ; 15(1): e0226838, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31990908

RESUMO

Lipases comprise a large class of hydrolytic enzymes which catalyze the cleavage of the ester bonds in triacylglycerols and find numerous biotechnological applications. Previously, we have cloned the gene coding for a novel esterase PMGL2 from a Siberian permafrost metagenomic DNA library. We have determined the 3D structure of PMGL2 which belongs to the hormone-sensitive lipase (HSL) family and contains a new variant of the active site motif, GCSAG. Similar to many other HSLs, PMGL2 forms dimers in solution and in the crystal. Our results demonstrated that PMGL2 and structurally characterized members of the GTSAG motif subfamily possess a common dimerization interface that significantly differs from that of members of the GDSAG subfamily of known structure. Moreover, PMGL2 had a unique organization of the active site cavity with significantly different topology compared to the other lipolytic enzymes from the HSL family with known structure including the distinct orientation of the active site entrances within the dimer and about four times larger size of the active site cavity. To study the role of the cysteine residue in GCSAG motif of PMGL2, the catalytic properties and structure of its double C173T/C202S mutant were examined and found to be very similar to the wild type protein. The presence of the bound PEG molecule in the active site of the mutant form allowed for precise mapping of the amino acid residues forming the substrate cavity.


Assuntos
Bactérias/enzimologia , Lipase/química , Lipase/metabolismo , Mutação , Pergelissolo/microbiologia , Motivos de Aminoácidos , Bactérias/química , Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Cristalografia por Raios X , Lipase/genética , Metagenoma , Modelos Moleculares , Conformação Proteica , Multimerização Proteica , Serina/metabolismo , Sibéria , Especificidade por Substrato
15.
Mar Environ Res ; 155: 104873, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31965975

RESUMO

Here, we investigated the elemental (C/N ratio) and isotopic signatures (δ13C) and major biomolecules (carbohydrates, proteins, and lipids) and their relative abundance (i.e., the biochemical composition) in particulate organic matter (POM) to assess their origin and fate in the Laptev and western East Siberian seas during late summer/fall of 2015. In addition, we compared our results with the summer data of 2013 collected from Laptev and northwestern East Siberian seas. In accordance with the observed hydrological structure (i.e., a northward, warmer, diluted freshwater plume than previously observed in 2013), the more depleted δ13C (-28.2 ± 0.9‰) and higher C/N ratio (10.8 ± 2.0) than those of 2013 signalled that fluvially released terrestrial organic carbon (TerrOC) was the main source of the POM, unlike in 2013, when phytoplankton was the dominant source (δ13C = -24.9 ± 1.0‰, C/N ratio = 7.6 ± 2.4; Ahn et al., 2019). During the offshore transport of heterogeneous TerrOC, carbohydrates seem to be the primary contributor to the bulk POM as a result of selective degradation and hydrodynamic sorting. Despite the TerrOC-dominated system in 2015, some marine influence was also found. The estimated phytoplankton biomass was low and comparable among the study sites. In addition, the presence of resting spores and high ammonium concentrations within the water column may suggest senescent and, to some extent, degrading conditions of the resident phytoplankton. In this regard, carbohydrate concentrations and freshwater content were significantly correlated (r = 0.79, p < 0.01), suggesting that carbohydrates are useful inferences of freshwater within overall study sites, at least when the marine influence is similar or low.


Assuntos
Material Particulado/química , Fitoplâncton , Água do Mar/química , Regiões Árticas , Isótopos de Carbono , Isótopos de Nitrogênio , Oceano Pacífico , Sibéria
16.
Environ Geochem Health ; 42(1): 325-341, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31218475

RESUMO

This study investigates the levels, sources, spatial distribution, and toxicity of polycyclic aromatic hydrocarbons (PAHs) in urban soils of Tyumen, Russia. Observations of PAHs in cities of Western Siberia accomplished by a representative set of samples are very rare, even though it is one of the most urbanized parts of Russia. Therefore, it is important to estimate the status of PAHs in soils of urban environments representing vast Siberian regions. Tyumen, as one of the most intensively developing cities of Western Siberia, is a good object for such studies. Topsoil samples (0-10 cm) were collected from 241 sampling sites on a regular grid within Tyumen city limits. It was found that total concentration of 12 priority PAHs ranged from 33.4 to 2147.9 µg kg-1, with a median value of 280.3 µg kg-1. High-molecular-weight (HMW) PAHs were dominant, accounting for the majority (62%) of the total PAHs. Among the PAHs in soils, 4-ring compounds were predominant in all studied samples, followed by 5- and 6-ring PAHs. Phenanthrene, pyrene, fluoranthene, and benzo(ghi)perylene had values of 28%, 19%, 15%, and 10% of total PAHs, respectively. Results showed that large high-contrast anomalies of HMW PAHs were related to low-residential and transport areas. The diagnostic ratios, as well as hierarchical cluster analysis (HCA) and principal component analysis (PCA), confirmed that sources associated with the transport were the most significant, while biomass combustion played an important role as a source of PAHs in agricultural, low-residential, and recreational areas. Levels of individual PAHs, as well as total PAHs in urban soils of Tyumen, were comparable with those in non-industrial cities with similar populations but were significantly lower than those in large industrial centers. Assessment of soil toxicity using toxic equivalent quantity (TEQBaP) showed that the TEQBaP values varied from 2.0 to 388.2 µg kg-1, with a mean value of 34.9 µg kg-1 and median of 19.8 µg kg-1, and were lower than those in heavy industrialized cities, but higher than those in soils of cities specializing in consumer and service industries.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Agricultura , Cidades , Análise por Conglomerados , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Indústrias , Análise de Componente Principal , Sibéria
17.
Environ Geochem Health ; 42(1): 221-240, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31187345

RESUMO

The main threats to health are associated with the entry of potentially toxic elements (PTEs) into human bodies. The aim of this study is to assess the impact of the Zakamensk W-Mo deposit development on soil surface horizons and the health of the local population. The results of the geochemical survey of 2012 revealed the spatial distribution patterns and abundances of 15 PTEs. The elements bulk contents were determined by ICP-MS and ICP-AES. The impact of geochemical situation on the health of the population of Zakamensk was also assessed using the mortality rates from diseases of the digestive and respiratory organs, neoplasms, including malignant tumors of the digestive and respiratory organs in 2008-2012. The tailing dumps have increased concentrations of W, Cd, Pb, Sb, Mo, Cu, Zn, Sn, As, and Co due to petrochemical characteristics of the ore. The soils of the industrial zone accumulate W, Cd, Mo, Pb, Sb, Zn, Cu, and Sn due to the waste storage sites deterioration and the thermal power plant and the foundry emissions. The multi-story residential zone soils accumulate W, Cd, Pb, Zn, and Mo. Tungsten, Pb, Sb, Co, V, and Cr cause the greatest harm to adults and children and together account for 92-96% of the hazard index. Cadmium and Cr are the most dangerous carcinogenic elements in Zakamensk. Despite the closure of DTMP more than 15 years ago, the level of the total risk of developing malignant diseases indicates a catastrophic environmental situation.


Assuntos
Exposição Ambiental/análise , Mortalidade , Poluentes do Solo/análise , Idoso , Carcinógenos/análise , Carcinógenos/toxicidade , Criança , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Feminino , Humanos , Masculino , Metais Pesados/análise , Metais Pesados/toxicidade , Pessoa de Meia-Idade , Mineração , Centrais Elétricas , Medição de Risco , Sibéria/epidemiologia , Poluentes do Solo/toxicidade
18.
Int J Syst Evol Microbiol ; 70(2): 929-934, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31730034

RESUMO

A novel actinobacterium, strain K3-2T, was isolated in pure culture from a thawing ancient ice wedge at Mammoth Mountain (Eastern Siberia, Russia). Colonies of strain K3-2T were yellowish orange; cells had the fine structure typical of Gram-positive bacteria, were non-motile short rods and were non-spore-forming. Strain K3-2T was mesophilic (optimum growth at 28 °Ð¡), but capable of growing at 4 °Ð¡. The cell-wall peptidoglycan of strain K3-2T contained lysine (the diagnostic diamino acid), glutamic acid, alanine, ornithine, glycine and serine. The polar lipids were phosphatidylglycerol, lysophosphatidylserine, three unidentified phospholipids and glycolipids. The major fatty acids were anteiso-C15 : 0 and C16 : 0. The only menaquinone detected was MK-8(H4). 16S rRNA gene analysis indicated that strain K3-2T belongs to the genus Serinibacter. The closest taxonomically described relatives were Serinibacter salmoneus Kis4-28T and Serinibacter tropicus PS-14-7T, with 97.20 and 97.20 % 16 s rRNA gene sequence similarity, respectively. The average nucleotide identity value of the whole genome sequence between strain K3-2T and S. salmoneus Kis4-28T was 78.9 %. DNA-DNA relatedness values between strain K3-2T and S. salmoneus DSM 21801T (=Kis4-28T) and S. tropicus VKPM Ac 2044T (=PS-14-7T) were 41 and 47 %. Thus, strain K3-2T represents a novel species of the genus Serinibacter for which the name Serinibacter arcticus sp. nov. is proposed. The type strain is K3-2T (DSM 103859T=VKM Ас-2719T).


Assuntos
Actinobacteria/classificação , Gelo , Filogenia , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sibéria , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
Environ Geochem Health ; 42(1): 159-171, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31111334

RESUMO

This study was aimed at assessment of strontium and calcium mobility in soils and their accumulation with plants in the areas endemic for Kashin-Beck disease in Eastern Transbaikalia. The strontium and calcium mobility levels were determined using the method of sequential chemical extraction for 7 samples of meadow soils collected from the endemic region and 7 soil samples taken from conditionally control sites. To measure the Ca and Sr levels in the soil and plant samples, XRF analysis and AAS were used. The increased strontium level in the meadow soils of the endemic areas is accompanied by the element's higher mobility. The highest strontium yield was observed in the course of soil extraction using 1 M ammonium acetate, while the soils taken from the control sites gave lower amounts of the trace element. Furthermore, there is a positive correlation between the amount of the strontium extracted and its content in plants (r = + 0.86 - 0.98). At the sequential chemical extraction of calcium from the soils using the above method, the calcium yield was maximal in the ammonium acetate fraction (background sites) and in ammonium acetate and 6 M HCl fractions (endemic areas). The correlation between the amount of the calcium extracted in 1 M ammonium acetate and the macroelement levels found in plants was + 0.968. In addition, a peculiarly high accumulation of strontium in various willow species as compared to other meadow plants was revealed for the first time ever. Thus, the work introduces new data into the trace element biogeochemistry and environmental monitoring.


Assuntos
Cálcio/análise , Doença de Kashin-Bek , Plantas/metabolismo , Solo/química , Estrôncio/análise , Bioacumulação , Cálcio/farmacocinética , Monitoramento Ambiental/métodos , Pradaria , Humanos , Plantas/química , Sibéria , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Estrôncio/farmacocinética
20.
J Environ Radioact ; 211: 106048, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31546081

RESUMO

The uranium and thorium contents in the soils and bottom sediments of the Lake Bolshoye Yarovoye natural system correspond to the data for the steppe climate zone and are noticeably lower than the background values for the Altai Territory as a whole. Factors that reduce the content of uranium and thorium are: 1 - lighter grain size distribution of the substrate, and, accordingly, the soils in this area; 2 - low content of organic matter (high ash content at 600 °C); 3 - the presence of significant quantities of quartz and calcite; 4 - general salinization of soils and the development of the solonchak process; 5 - remoteness from the region of material removal from the Altai mountains with its uranium-thorium-bearing granites and various mineraliszation. The distribution of uranium and thorium in the soils of the catchment area is heterogeneous. Minimum contents are observed in the soils of the boggy eastern coast and in its southern part in connection with the development of the solonchak process. This part of the catchment is characterized by high salinity (HCO3-- Na+) of water extracts in soils. Under subalkaline and alkaline conditions (pH 7.1-8.4) in soil waters, an increase in the content of these ions facilitates the transition of uranium to the liquid phase and its migration to the lake. In this part of the water area, the maximum uranium content in bottom sediments is observed. The results of cluster analysis indicate a change in the correlation of uranium and thorium during their redistribution from soils to bottom sediments. In soils, there is no correlation between uranium and thorium; in the bottom sediments, a strong positive correlation is observed between them (correlation coefficient 0.9). Uranium in soils has only a bond with Cr and possibly with Mn. The absence of a correlation with the elements of the mineral component of the soil confirms it finding, mainly in soluble form. In bottom sediments, both elements are associated with the mineral component. The established features of the distribution of uranium and thorium in the soils and bottom sediments of Lake Bolshoye Yarovoye indicate the need for detailed geochemical studies in lakes of a similar type. This will help to avoid ecological risks when choosing such lakes as anthropogenic objects.


Assuntos
Monitoramento de Radiação , Solo , Sedimentos Geológicos , Lagos , Sibéria , Tório , Urânio
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