Northern Siberia Research Articles

Microbial lipid signatures and substrate potential of organic matter in permafrost deposits: Implications for future greenhouse gas production

AbstractA terrestrial permafrost core from Buor Khaya in northern Siberia comprising deposits of Late Pleistocene to Early Holocene age has been investigated to characterize living and past microbial communities with respect to modern and paleoclimate environmental conditions and to evaluate the potential of the organic matter (OM) for greenhouse gas generation. Microbial life markers—intact phospholipids and phospholipid fatty acids—are found throughout the entire core and indicate the presence of living microorganisms also in older permafrost deposits. Biomarkers for past microbial communities (branched and isoprenoid glycerol dialkyl glycerol tetraether as well as archaeol) reveal links between increased past microbial activity and intervals of high OM accumulation accompanied by increased OM quality presumably caused by local periods of moister and warmer environmental conditions. Concentrations of acetate as an excellent substrate for methanogenesis are used to assess the OM quality with respect to microbial degradability for greenhouse gas production. For this purpose two acetate pools are determined: the pore water acetate and OM bound acetate. Both depth profiles reveal similarities to the OM content and quality indicating a link between the amount of the stored OM and the potential to provide substrates for microbial greenhouse gas production. The data suggest that OM stored in the permafrost deposits is not much different in terms of OM quality than the fresh surface organic material. Considering the expected increase of permafrost thaw due to climate warming, this implies a potentially strong impact on greenhouse gas generation from permafrost areas in future with positive feedback on climate variation.

A new Eurasian phylogeographical paradigm? Limited contribution of southern populations to the recolonization of high latitude populations in Juniperus communis L. (Cupressaceae)

AbstractAimThe aims of this population genetics study of the common juniper across Eurasia were to (1) assess the contribution of southern mountain ranges to the post‐glacial recolonization of high latitudes and (2) test whether recent expansion or high gene flow could explain the low genetic differentiation in Northern Eurasia.LocationNorthern Eurasia and mountain regions of Central Europe and Asia.MethodsSix hundred and twenty‐two individuals were sampled in 42 populations. Two chloroplast DNA (cpDNA) fragments were investigated (trnT‐trnL and 16S‐trnA). Analyses of the distribution of haplotypes across the continent included a suite of phylogeographical and phylogenetic tests. Putative geographical distribution in the past was reconstructed using environmental niche modelling.ResultsEighty‐four haplotypes clustered into four main clades (GL1‐GL4). The largest clade, GL3, corresponds to populations from the Alps, northern Europe, Western Caucasus and Siberia. These populations were moderately differentiated (28%) compared to the total range (76%) and Fu's Fs statistic was negative, indicating a population expansion. Some haplotypes within GL3 form subclades with a restricted geographical distribution, suggesting a local origin of the mutation and limited dispersal. In line with these findings, modelling of ecological niches found no significant reduction in the expected range during the LGM. Remarkably, populations from the eastern part of North Caucasus, the Himalayas, Tien Shan and south Siberia were distinctly different from populations in the rest of the range.Main conclusionsAs in Siberian larch species, the pattern of genetic diversity at cpDNA across the natural range of J. communis suggests that colonization of northern Europe and Siberia started from a limited area and predated the last glaciation. It is likely that juniper survived the subsequent glacial epoch at high latitudes in cryptic refugia serving as secondary centres of recolonization. Southern mountain refugia contribution to the recolonization of high latitudes was, at best, limited.

Effects of a Warming Climate on Daily Snowfall Events in the Northern Hemisphere

Abstract Using simulations performed with 24 coupled atmosphere–ocean global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5), projections of Northern Hemisphere daily snowfall events under the RCP8.5 emissions scenario are analyzed for the periods of 2021–50 and 2071–2100 and compared to the historical period of 1971–2000. The overall frequency of daily snowfall events is simulated to decrease across much of the Northern Hemisphere, except at the highest latitudes such as northern Canada, northern Siberia, and Greenland. Seasonal redistributions of daily snowfall event frequency and average daily snowfall are also projected to occur in some regions. For example, large portions of the Northern Hemisphere, including much of Canada, Tibet, northern Scandinavia, northern Siberia, and Greenland, are projected to experience increases in average daily snowfall and event frequency in midwinter. But in warmer months, the regions with increased snowfall become fewer in number and are limited to northern Canada, northern Siberia, and Greenland. These simulations also show changes in the frequency distribution of daily snowfall event intensity, including an increase in heavier snowfall events even in some regions where the overall snowfall decreases. The projected changes in daily snowfall event frequency exhibit some dependence on the temperature biases of the individual models in certain regions and times of the year, with colder models typically toward the positive end of the distribution of event frequency changes and warmer models toward the negative end, particularly in regions near the transition zone between increasing and decreasing snowfall.

Spaceborne potential for examining taiga-tundra ecotone form and vulnerability.

In the taiga-tundra ecotone (TTE), site-dependent forest structure characteristics can influence the subtle and heterogeneous structural changes that occur across the broad circumpolar extent. Such changes may be related to ecotone form, described by the horizontal and vertical patterns of forest structure (e.g., tree cover, density and height) within TTE forest patches, driven by local site conditions, and linked to ecotone dynamics. The unique circumstance of subtle, variable and widespread vegetation change warrants the application of spaceborne data including high-resolution (< 5m) spaceborne imagery (HRSI) across broad scales for examining TTE form and predicting dynamics. This study analyzes forest structure at the patch-scale in the TTE to provide a means to examine both vertical and horizontal components of ecotone form. We demonstrate the potential of spaceborne data for integrating forest height and density to assess TTE form at the scale of forest patches across the circumpolar biome by (1) mapping forest patches in study sites along the TTE in northern Siberia with a multi-resolution suite of spaceborne data, and (2) examining the uncertainty of forest patch height from this suite of data across sites of primarily diffuse TTE forms. Results demonstrate the opportunities for improving patch-scale spaceborne estimates of forest height, the vertical component of TTE form, with HRSI. The distribution of relative maximum height uncertainty based on prediction intervals is centered at ~40%, constraining the use of height for discerning differences in forest patches. We discuss this uncertainty in light of a conceptual model of general ecotone forms, and highlight how the uncertainty of spaceborne estimates of height can contribute to the uncertainty in identifying TTE forms. A focus on reducing the uncertainty of height estimates in forest patches may improve depiction of TTE form, which may help explain variable forest responses in the TTE to climate change and the vulnerability of portions of the TTE to forest structure change.

Controls on the storage of organic carbon in permafrost soil in northern Siberia

SummaryThis research examined soil organic carbon (SOC), total nitrogen (TN) and aboveground phytomass carbon (PhC) stocks in two areas of the Taymyr Peninsula, northern Siberia. We combined field sampling, chemical and 14C radiocarbon dating analyses with land cover classifications for landscape‐level assessments. The estimated mean for the 0–100‐cm depth SOC stocks was 14.8 and 20.8 kg C m−2 in Ary‐Mas and Logata, respectively. The corresponding values for TN were 1.0 and 1.3 kg N m−2. On average, about 2% only (range 0–12%) of the total ecosystem C is stored in PhC. In both study areas about 34% of the SOC at 0–100 cm is stored in cryoturbated pockets, which have formed since at least the early Holocene. The larger carbon/nitrogen (C/N) ratio of this cryoturbated material indicates that it consists of relatively undecomposed soil organic matter (SOM). There are substantial differences in SOC stocks and SOM properties within and between the two study areas, which emphasizes the need to consider both geomorphology and soil texture in the assessment of landscape‐level and regional SOC stocks.Highlights This research addresses landscape‐scale and regional variation in SOC stocks. Landform and soil texture are taken into account in the analysis. The contribution of phytomass to total ecosystem C stored is limited. Large SOC stocks are susceptible to decomposition following permafrost thaw.

Trends In Elemental Concentrations of Tree Rings From the Siberian Arctic

ABSTRACT The biogeochemistry and ecology of the Arctic environment have been heavily impacted by anthropogenic pollution and climate change. We used ICP-MS to measure concentrations of 26 elements in the AD 1300–2000 tree rings of larch from the Taymyr Peninsula in northern Siberia for studying the interaction between environmental change and wood chemistry. We applied a two-stage data reduction technique to identify trends in the noisy measurement data. Statistical assessment of variance of normalized time series reveals pronounced depletion of xylem Ca, Mg, Cl, Bi and Si concentrations and enrichment of P, K, Mn, Rb, Sr and Ba concentrations after ca. AD 1900. The trends are unprecedented in the 700-year records, but multiple mechanisms may be at work and difficult to attribute with certainty. The declining xylem Ca and Mg may be a response to soil acidification from air pollution, whereas increasing P, K, and Mn concentrations may signal changes in root efficiency and excess water-soluble minerals libe...

VEGETATION COVER MAPPING BASED ON REMOTE SENSING AND DIGITAL ELEVATION MODEL DATA

Abstract. An algorithm of forest cover mapping based on combined GIS-based analysis of multi-band satellite imagery, digital elevation model, and ground truth data was developed. Using the classification principles and an approach of Russian forest scientist Kolesnikov, maps of forest types and forest growing conditions (FGC) were build. The first map is based on RS-composite classification, while the second map is constructed on the basis of DEM-composite classification. The spatial combination of this two layers were also used for extrapolation and mapping of ecosystem carbon stock values (kgC/m2). The proposed approach was applied for the test site area (~3600 km2), located in the Northern Siberia boreal forests of Evenkia near Tura settlement.

VEGETATION COVER MAPPING BASED ON REMOTE SENSING AND DIGITAL ELEVATION MODEL DATA

An algorithm of forest cover mapping based on combined GIS-based analysis of multi-band satellite imagery, digital elevation model, and ground truth data was developed. Using the classification principles and an approach of Russian forest scientist Kolesnikov, maps of forest types and forest growing conditions (FGC) were build. The first map is based on RS-composite classification, while the second map is constructed on the basis of DEM-composite classification. The spatial combination of this two layers were also used for extrapolation and mapping of ecosystem carbon stock values (kgC/m&amp;lt;sup&amp;gt;2&amp;lt;/sup&amp;gt;). The proposed approach was applied for the test site area (~3600 km&amp;lt;sup&amp;gt;2&amp;lt;/sup&amp;gt;), located in the Northern Siberia boreal forests of Evenkia near Tura settlement.

Paleomagnetism of Mesoproterozoic margins of the Anabar Shield: A hypothesized billion-year partnership of Siberia and northern Laurentia

Siberia and Laurentia have been suggested as near neighbors in Proterozoic supercontinents Nuna and Rodinia, but paleomagnetic evidence has been sparse and ambiguous. Here we present four new paleomagnetic poles from undeformed Paleo-Mesoproterozoic (lower Riphean) sedimentary rocks and mafic intrusions of the northwestern Anabar uplift in northern Siberia. Combining these results with other Proterozoic data from Siberia and Laurentia, we propose a tight juxtaposition of those two blocks (Euler parameters 77°, 098°, 137° for Anabar to North America) spanning the interval 1.7–0.7Ga, constituting a long-lived connection that outlasted both the Nuna and Rodinia supercontinental assemblages.

A genetic perspective of prehistoric hunter-gatherers in the Siberian Arctic: Mitochondrial DNA analysis of human remains from 8000 years ago

Archaeological evidence of human occupation in Arctic Siberia dates to at least 27,000years before present (YBP) but the population history of these early inhabitants is not fully understood. Genetic research on contemporary indigenous Siberian populations has suggested a distinct pattern between populations from south/central Siberia and the extreme northeast Siberia. However, the picture is complicated by the fluctuations of movement by various cultural groups in the last millennium that has resulted in admixture as well as genetic drift. In order to better understand the genetic history of early humans in northern Siberia, we obtained ten human skeletal remains from four areas of the eastern Siberian Arctic, stretching from the low Yana River in the west to midstream of Bol'shaya Chukoch'ya River and Kolyma River in the east, and the Zhokhov site in the New Siberian Islands. We extracted DNA from the skeletal remains ranging from around 27,000YBP to as recent as the 18th century AD and analyzed the mitochondrial DNA (mtDNA) control region. We successfully identified five haplotypes that include haplogroups A2 and C4. The presence of haplogroup C4 in Arctic Siberia by 8000years ago illustrates the antiquity and widespread distribution of the maternal lineage in the region. On the other hand, haplogroup A2 is frequent among contemporary northeastern Siberian populations. Overall, the results from our ancient DNA analysis suggest maternal lineages among contemporary Siberians were present as far back as 8000years ago in the Siberian Arctic.

About the age and habitat of the Kirgilyakh mammoth (Dima), Western Beringia

The unearthing in 1977 of a complete frozen carcass of a young mammoth, known as the Kirgilyakh mammoth or Dima: 1) provided the first opportunity for detailed study of the anatomy of a mammoth calf; 2) provided a more detailed understanding of interstadial landscapes; and 3) suggested paleoclimatic variability occurred in Western Beringia during marine isotope stage (MIS) 3. Limited access to early Russian literature resulted in unfortunate misinformation in English-language publications. Since then, six other juvenile carcasses have been discovered in northern Siberia and additional Late Pleistocene paleobotanical records have increased understanding of MIS2 and MIS3 environments. Given the new data, it seems timely to re-examine information about the Kirgilyakh mammoth in the context of: 1) correcting mistakes about the age and environments of the site, including the manner of the mammoth’s death; 2) comparing paleoenvironmental settings with that of other young mammoth carcasses; and 3) revisiting the concept of mammoth-steppe. This re-examination, which places the Kirgilyakh results in a broader spatial-temporal setting, reinforces the idea that climatic variability, including the Kirgilyakh cool interval, characterized MIS3. Unstable landscapes in mountains and lowlands were key factors in deaths of the Siberian mammoth calves. The prevalence of tundra in MIS2 model reconstructions and abundance of paleobotanical data indicating mesic tundra and forest during MIS3 suggest that classification of these intervals as mammoth-steppe is problematic.

Trend and pattern classification of surface air temperature change in the Arctic region

AbstractMonthly seasonally adjusted temperatures above latitude 45°N were investigated from January 1973 to November 2013. The study area was divided into 69 sub‐regions of similar size each in the shape of an igloo brick. The data were filtered with a second‐order autoregressive process to remove autocorrelation. Two sub‐regions did not have sufficient data due to substantial numbers of missing values. Factor analysis was then applied to the remaining 67 sub‐regions and was used to classify regions with similar temperature changes. As a result, 63 sub‐regions could be classified based on 12 factors but 4 sub‐regions could not be grouped due to uniqueness. The temperatures for each group of sub‐regions were found to increase during 1973–2013. The largest temperature increases of 0.19 °C/decade were found in northern and southern Siberia and part of the Arctic Ocean. In northern Canada, Alaska, the northern Pacific Ocean and eastern Siberia the temperatures increased by at least 0.16 °C/decade. In Iceland, Norway, Sweden and part of the Pacific and Arctic Oceans the temperature increased by around 0.15 °C/decade. In northeastern Canada, Greenland and its surrounding Atlantic Ocean and the Arctic Ocean the temperature increased by about 0.15 °C/decade.

The extant genus Eutheia (Coleoptera: Staphylinidae: Scydmaeninae) discovered in Upper Cretaceous Taimyr amber

The Eutheiini includes over 90 extant species classified in seven genera and distributed predominantly in the Northern Hemisphere. So far only one extinct genus and species unambiguously placed in this tribe has been known, Archeutheia, from Albian of Spain. We report the discovery of Eutheia, a member of the largest extant genus of Eutheiini, in Santonian of northern Siberia. Extant species of Eutheia are primarily defined on the basis of male genital characters, and the specimen discovered in Taimyr amber is a female; consequently it is described as Eutheia sp. The new finding remarkably extends the known range of Eutheiini during Cretaceous over the area of about 6 thousand kilometers, from the Iberian Plate to northern Siberia. A long morphological stasis in Eutheia suggests that this genus was associated with stable mesic microhabitats of the upper soil layers or rotten wood for at least 83 my.

Phylogenetic inference and peristome evolution in haplolepideous mosses, focusing on Pseudoditrichaceae and Ditrichaceaes. l.

Pseudoditrichum mirabile, the only species of Pseudoditrichaceae, has been known for a long time from a single collection from the Canadian Arctic. Its systematic position remained enigmatic due to similarity in gametophyte structure with Ditrichaceae, a family that has simple peristomes, whereas the peristome in Pseudoditrichum is double. Due to this difference, Pseudoditrichum was classified in either Funariales or Bryales. A recent discovery of this species in the Anabar Plateau in northern Siberia has allowed its phylogenetic position to be tested based on plastid rps4 and rbcL and mitochondrial nad5 sequences. The results of this research reject the earlier hypotheses. Instead, the molecular analysis resolves Pseudoditrichum in a clade with Chrysoblastella chilensis (formerly Ditrichaceae) in the haplolepideous lineage. The peristome of Pseudoditrichum is of a previously unknown type with a fully developed exostome and hyaline endostome elements opposite the exostome teeth, based not on the 4:2:4 peristomial formula, but on 4:2:3. Double peristomes of the same type, albeit rather strongly reduced, occur in Catoscopium, Chrysoblastella, Distichium and Ditrichum flexicaule. The polyphyly of Ditrichaceae is confirmed by molecular phylogenetic analysis, and Ditrichum flexicaule and D. gracile are segregated into the new genus Flexitrichum and family Flexitrichaceae. An independent status of the recently resurrected family Distichiaceae is supported, and segregation of Chrysoblastella and Saelania into new monospecific families is proposed.

Flora from the Induan stage (Lower Triassic) of Middle Siberia

The first data on the taxonomic composition of the Induan flora of Siberia are presented. The investigation of Triassic reference sections in northern Siberia (eastern Taimyr, Lena–Anabar Trough, Verkhoyansk region) and correlation with volcano-sedimentary complexes of the Tungus and Kuznetsk basins made it possible to establish for the first time the taxonomic composition of the flora from the Induan Stage of Siberia. Its composition is heterogeneous, forming two large plant formations, which occupied different ecological niches. On the eastern coastal-marine margins of Siberia (eastern Taimyr, Olenek coast, Verkhoyansk region), the Induan flora was largely characterized by lepidophytic (Tomiostrobus) plants, while in the intracontinental areas (Tungus and Kuznetsk basins, partly Verkhoyansk region), it was characterized by Equisetales–Filicales communities.

The 1501 Ma Kuonamka Large Igneous Province of northern Siberia: U-Pb geochronology, geochemistry, and links with coeval magmatism on other crustal blocks

A new large igneous province (LIP), the 1501 ± 3 Ma Kuonamka LIP, extends across 700 km of northern Siberia and is linked with coeval dikes and sills in the formerly attached Sao Francisco craton (SFC)-Congo craton to yield a short-duration event 2000 km across. The age of the Kuonamka LIP can be summarized as 1501 ± 3 Ma (95% confidence), based on 7 U-Pb ID-TIMS ages (6 new herein) from dolerite dikes and sills across the Anabar shield and within western Riphean cover rocks for a distance of 270 km. An additional sill yielded a SIMS (CAMECA) age of 1483 ± 17 Ma and sill in the Olenek uplift several hundred kilometers farther east, a previous SIMS (SHRIMP) age of ca. 1473 Ma was obtained on a sill; both SIMS ages are within the age uncertainty of the ID-TIMS ages. Geochemical data indicate a tholeiitic basalt composition with low MgO (4–7 wt%) within-plate character based on trace element classification diagrams and source between E-MORB and OIB with only minor contamination from crust or metasomatized lithospheric mantle. Two subgroups are distinguished: Group 1 has gently sloping LREE ((La/Sm)PM = 1.9) and HREE ((Gd/Yb)PM = 1.8) patterns, slightly negative Sr and moderate TiO2 (2.2 wt%), and Group 2 has steeper LREE ((La/Sm)PM = 2.3) and HREE ((Gd/Yb)PM = 2.3), strong negative Sr anomaly, is higher in TiO2 (2.7 wt%), and is transitional from tholeiitic to weakly alkaline in composition. The slight differences in REE slopes are consistent with Group 2 on average melting at deeper levels. Proposed reconstructions of the Kuonamka LIP with 1500 Ma magmatism of the SFC-Congo craton are supported by a geochemical comparison. Specifically, the chemistry of the Chapada Diamantina and Curaga dikes of the SFC can be linked to that of Groups 1 and 2, respectively, of the Kuonamka LIP and are consistent with a common mantle source between EMORB and OIB and subsequent differentiation history. However, the coeval Humpata sills and dikes of the Angola block of the Congo craton represent a different magma batch.

The Effects of Wealth on Male Reproduction among Monogamous Hunter-Fisher-Trappers in Northern Siberia

Variability in men’s reproductive success (RS) is partly attributable to the ability of successful men to influence resource flows relevant to the mate choice and reproduction of women. This study explores the effects of variability in resource flows on men’s RS in an indigenous foraging/mixed-economy community in northern Siberia where monogamous marriage norms predominate. A series of material, embodied, and relational wealth indicators are tested as predictors of men’s age-adjusted RS and age at first birth. Material wealth related to hunting, embodied wealth as represented by hunting skill, and relational wealth as represented by numbers of kin are the most consistent predictors of men’s RS. In this monogamous population, the wives of men with more hunting capital and of men rated as better hunters have shorter interbirth intervals, and hunters show strong producer priority. These findings and ethnographic observations appear more consistent with a provisioning model than with a signaling-for-mates model.

An interesting new species of Sisyridae (Neuroptera) from the Upper Cretaceous Taimyr amber

Prosisyrina sphinga sp. nov. (Neuroptera: Sisyridae) is described from Upper Cretaceous (Santonian) Taimyr amber of northern Siberia (Yantardakh locality). The new species is preliminary assigned to this Cretaceous genus, mainly based on character states of the maxillary palpus and the hind wing vein M and crossvein 1r-m, and the presumable absence of tibial false spurs. However, the structure of the costal space and the RP branching in the hind wing indicate that it may belong to a new, closely related genus. The discovery of this second species from the locality might suggest that sisyrids were usual members of the Santonian riparian biocenoses of northern Siberia.

Devonian–Permian sedimentary basins and paleogeography of the Eastern Russian Arctic: An overview

The Arctic basins attract broad international interest because of the region's potentially significant undiscovered hydrocarbon resources. The Russian High Arctic is mostly represented by broad shelves, with a few wells drilled only in its western part (Kara and Barents shelves). This contribution provides an overview of the geological setting, stratigraphy, paleogeography, and tectono-sedimentary evolution of the middle–late Paleozoic basins of the Eastern Russian Arctic, including: Severnaya Zemlya, the New Siberian Islands, northern Siberia, the Taimyr and Chukotka peninsulas, and Wrangel Island. Reconstructing the geological evolution of the Eastern Russian Arctic during the middle–late Paleozoic is very difficult because the region was overprinted by a number of late Paleozoic to early Mesozoic tectonic events.

Trans-Siberian Permian rivers: A key to understanding Arctic sedimentary provenance

Permian strata of northern Siberia contain a rich record of the late Paleozoic history of Siberia and surrounding fold and thrust belts (FTB). More than 850 uranium–lead (U–Pb) detrital zircon ages collected from the Permian strata provide vital information about sediment source areas and history of the sedimentary basins. The detrital zircon populations obtained from the Permian clastics of northern Siberia are characterized by large percentages of late Paleozoic and early Paleozoic zircons, whose ages can be correlated with magmatic events known from the Ural-Mongolian Orogen. Our data suggest that Permian clastics of northern Siberia were mainly sourced from orogens developed along the western and southwestern margins of the Siberian Craton (in present-day coordinates), with an additional sediment contribution from the reworked sedimentary cover and basement of Siberia. The contribution from Siberian sources is distinguished in the Precambrian part of the detrital zircon populations by wide distribution of ca. 1700–2000Ma and 2500–2750Ma zircons with an almost total lack of zircons ranging in age from 800 to 1700Ma. We propose that a major fluvial system, which we here term the “Paleo-Khatanga”, was the main sediment transport pathway along the western and northern margins of Siberia during the Permian. From a regional overview of detrital zircon populations in Permian deposits across the Arctic realm, we propose that the New Siberian Islands, Alexander and Farewell terranes were sourced from the western framework of the Ural-Mongolian Orogen and were located along the northern margin of Baltica during the late Paleozoic. The Arctic–Alaska–Chukotka Terrane on the other hand does not have Uralian signatures in the detrital zircon populations of the Permian sediments, and can be reconstructed adjacent to the northern margin of Laurentia. Our new data presented here help to better define the enigma of Arctic paleogeography during the Paleozoic.