Kolyma Lowland Research Articles

Modern tundra landscapes of the Kolyma Lowland and their evolution in the Holocene

AbstractThe different tundra landscapes of the Kolyma Lowland, northern Siberia are described, focusing on landscape typology, digital mapping and the calculation of areas occupied by different landscape complexes. The genesis, age and evolution of ‘yedoma’ sediments and associated alas (thermokarst basins) topography are inferred from the calculation of lake‐basin and lake‐area changes over three decades. Connections between the present landscape and its evolution during the Holocene are described. Copyright © 2009 John Wiley & Sons, Ltd.

Preliminary study of a mummified woolly rhinoceros from the lower reaches of the Kolyma River

Blum., 1799) (Fig. 1) wasfound on the right bank of the Lower Kolyma River, ina gold field at the upper reaches of the Malaya Filip-pova River (8 km east of the village of Cherskii of theNizhnekolymskii District of Yakutia). We studied theburial place on October 10, 2007, and the specimen inMarch, 2008, as it was brought to the MammothMuseum of the Institute of Applied Ecology of North,Yakutsk (IPES). Most of the mummified corpse waspreserved, including the left half of the trunk, with skinof the head and ear, the skull with the lower jaw, thefore and hind legs (Figs. 1–3). Small bunches of shortcoarse light brown wool are only preserved on lowersites of legs. The right side of the body and the rightlegs are lost (apparently, cut off by a bulldozer). Mostof the inner organs are lost; however, intestine is prob-ably partially preserved. The same locality has yielded anumber of specimens isolated from the trunk, i.e., the rightpelvis, the lower part of the right hind leg with soft tissues(Fig. 3b), and bones of the right foreleg (humerus, ulna,carpals, metacarpals, and two ungual phalanges). Hornshave not been found. The fragmentary genitals preservedin the specimen show that this is a female.The body measurements of this individual are ratherlarge, close to those of other adult female woolly rhi-noceroses (Table 1) [1]; the specimen weighs about900 kg; hence, during its life, the animal was about1.5 tons. The parietal length of the skull is 763 mm, thezygomatic width is 332 mm, the length of the uppertooth row is 217 mm. The mandible from the symphysisto the posterior edge of the articular process is 562 mmlong, the tooth row is 212 mm long, the ascendingramus measured from the apex of the articular processis 265 mm high. The teeth has wear signs; the majorsutures on the skull are obliterated; the nasal septum iscompletely ossified. These features, along with thebody and skull measurements, strongly suggest that therhinoceros from the vicinity of the village of Cherskiiwas an adult.The locality is situated on the left slope of east expo-sition at approximately 130 m above sea level. Thebone-bearing bed is at a depth of 5–9 m, composed offrozen dark gray loam of the Edoma Formation (glacialassemblage), with ice interbeds. Mostly loose, icy Qua-ternary deposits at the upper reaches of the Malaya Fil-ippova River form the strata about 15–17 m thick. Theburial place is at the junction of the northeastern part ofthe Kolyma Lowland and hilly spurs of the Anui Pla-teau, at about 200–630 m above sea level. According tothe soil geographical zonation, the area under study isat the boundary of the forest–tundra plain and theAlazeya–Yukagir plateau–tundra–taiga province of thetundra–forest subzone. Recent soils at the upperreaches of the Malaya Filippova River are formed oftypical cryogenic and taiga permafrost soils with vary-ing peaty and gleyey admixture. They show a high con-tent of organic matter, loamy particle-size distribution,neutral and subacid reaction, and high enzymaticpotential. Vegetation in the area studied belongs to thethin northern larch forest subzone [2]. In elevated sites,this is light larch forest, frequently with continuousmossy–lichen cover, dense undergrowth of five or sixwillow species, dwarf and Middendorf’s birches, inplaces, Manchurian alder, abundant low shrubs, andwith a small admixture of grasses and forbs. Hills arecovered with the dwarf stone pine. Lowered areas fre-quently have marshy moss–frutescent or grass–mossyopen woodlands.Paleoecological conditions in the habitat of theKolyma rhinoceros was reconstructed based on palyno-logical analysis; the ground sample comes from pri-

Diagnostics of gleyzation upon a low content of iron oxides (Using the example of tundra soils in the Kolyma Lowland)

The matrix of iron (hydr)oxides exerts a decisive influence on the character of gleyzation. Upon a high content of iron (hydr)oxides, their reduction radically changes the horizon color from warm to cold hues, which is typical of soils on the Russian Plain. Upon the low content of iron (hydr)oxides, iron reduction takes place in phyllosilicates with minimal changes in the soil color. The cold hue of cryohydromorphic soils in the Kolyma Lowland is controlled by the color of the lithogenic matrix with a low content of iron (hydr)oxides. In this case, the soil color characteristics expressed in the Munsell notation or in the CIE-L*a*b* system are ineffective for diagnostic purposes. The colorimetric methods appear to be more efficient after the soil pretreatment with hydrogen peroxide, as the gleyed horizons turn green, while the nongleyed (and not overmoistened) horizons turn red. Physical methods (Mossbauer spectroscopy and magnetic susceptibility measurements) are more efficient for characterizing the properties of iron compounds in cryohydromorphic soils as compared with the methods of chemical extraction. Mossbauer spectroscopy proved to be highly efficient, as the iron oxidation index Fe3+/(Fe2++Fe3+) decreases in the gleyed horizons. Chemical reagents (Tamm’s and Mehra-Jackson’s reagents) dissolve Fe-phyllosilicates and are not selective in soils with a low content of iron (hydr)oxides.

Radiocarbon dates of evolution cycles of thermokarst lakes on the Kolyma Lowland

Radiocarbon dates of evolution cycles of thermokarst lakes on the Kolyma Lowland

Effect of low temperature and culture media on the growth and freeze-thawing tolerance of Exiguobacterium strains

Bacteria of the genus Exiguobacterium have been repeatedly isolated from ancient permafrost sediments of the Kolyma lowland of Northeast Eurasia. Here we report that the Siberian permafrost isolates Exiguobacterium sibiricum 255-15, E. sibiricum 7-3, Exiguobacterium undae 190-11 and E. sp. 5138, as well as Exiguobacterium antarcticum DSM 14480, isolated from a microbial mat sample of Lake Fryxell (McMurdo Dry Valleys, Antarctica), were able to grow at temperatures ranging from −6 to 40 °C. In comparison to cells grown at 24 °C, the cold-grown cells of these strains tended to be longer and wider. We also investigated the effect of growth conditions (broth or surface growth, and temperature) on cryotolerance of the Exiguobacterium strains. Bacteria grown in broth at 4 °C showed markedly greater survival following freeze-thawing treatments (20 repeated cycles) than bacteria grown in broth at 24 °C. Surprisingly, significant protection to repeated freeze-thawing was also observed when bacteria were grown on agar at either 4 or 24 °C.

Paleobotanical analysis of materials from fossil gopher burrows and upper pleistocene host deposits, the Kolyma River lower reaches

The comparative analysis of palynomorphs and plant megafossils (fruits, seeds, twigs, leaves) in the Upper Pleistocene host sediments and materials filling in fossil burrows of gophers, their coprolites included, at the Duvannyi Yar, Stanchikovskii Yar and Zelenyi Mys sites of the Kolyma Lowland is carried out. Genera Salix, Lychnis, Silene, Draba, Potentilla, Larix, and families Poaceae, Polygonaceae, Cyperaceae, Compositae, and Leguminosae are determined among palynological remains and megafossils. Factors responsible for qualitative and quantitative differences in taxonomic compositions of palynological and megafossil assemblages are biological peculiarities of plants, different character of fossilization of palynomorphs and large plant remains, geographic conditions, different genesis of assemblages (allochthonous for microfossils and autochthonous for megafossils), and inadequately known morphology of certain spore and pollen taxa. The comprehensive paleobotanical analysis leads to the conclusion that the study region was occupied in the Late Pleistocene by plant communities of humid to somewhat dryer tundra with separate areas of pioneering and steppe vegetation.

Bacterial Community in Ancient Siberian Permafrost as Characterized by Culture and Culture-Independent Methods

The microbial composition of ancient permafrost sediments from the Kolyma lowland of Northeast Eurasia was examined through culture and culture-independent approaches. These sediments have been continuously frozen for 5,000 to 2-3 million years. A total of 265 Bacteria 16S rRNA gene sequences were amplified from the permafrost total-community genomic DNA and screened by amplified ribosomal 16S rRNA restriction analysis. Members of three major lineages were found: gamma-Proteobacteria (mostly Xanthomonadaceae), Actinobacteria, and Firmicutes. We also determined partial 16S rRNA gene sequences of 49 isolates from a collection of 462 aerobes isolated from these sediments. The bacteria included Actinomycetales (Arthrobacter and Microbacteriaceae); followed by the Firmicutes (Exiguobacterium and Planomicrobium); the Bacteroidetes (Flavobacterium); the gamma-Proteobacteria (Psychrobacter); and the alpha-Proteobacteria (Sphingomonas). Both culture and culture-independent approaches showed the presence of high and low G+C Gram-positive bacteria and gamma-Proteobacteria. Some of the 16S rRNA gene sequences of environmental clones matched those of Arthrobacter isolates. Two-thirds of the isolates grew at -2.5 degrees C, indicating that they are psychroactive, and all are closely related to phylogenetic groups with strains from other cold environments, mostly commonly from Antarctica. The culturable and non-culturable microorganisms found in the terrestrial permafrost provide a prototype for possible life on the cryogenic planets of the Solar System.

Mycelial fungi in cryopegs

Mycelial fungi from cryopegs (tundra, Kolyma lowland, Russia) have been studied. The use of media with different amounts of salt and cultivation at 4 and 25 °C allowed us to isolate filamentous fungi assigned to 11 species. The micromycetes of genus Geomyces were found most often. The total amount of fungi reached 1–4×102 CFU ml−1 of water. The extreme conditions of the cryopegs – the high salinity of the water (150–200 g l−1) and the constant low temperatures (average annual temperature is from −9 to −11 °C) – might serve as a model for the conditions of interplanetary environments.

Spatial and Temporal Observations of Seasonal Thaw in the Northern Kolyma Lowland

Observations carried out in 1996-2002 in the northern part of the Kolyma Lowland reveal spatial and temporal regularities in the seasonal thawing of tundra and northern taiga soils. The main factor determining differences in active-layer thickness in zonal tundra landscapes is the texture (mechanical composition) of soil parent material. Summer thaw in sandy soils is 2-3 times deeper than in loamy soils. The distribution of maximum seasonal thaw depth in watersheds and on hillslopes with loamy soils is influenced strongly by climatic zonality, which manifests itself through an increase in the depth of thaw from the arctic tundra to northern taiga. River floodplains, thermokarst depressions (alasy), and polygonal bogs have thinner active layers than adjoining watersheds. A direct correlation exists between seasonal thaw depth and mean summer air temperature in most zonal landscapes. In many cases a tendency for increased thaw depth was observed in the warm summer of 2000-2002. An inverse correlation between seasonal thaw depth and total summer precipitation occurs in most zonal biogeocenoses with loamy soils and intrazonal landscapes. This relationship was not found in well-drained zonal tundra and taiga biogeocenoses with sandy soils or in the most waterlogged alas we examined.

A novel mannitol teichoic acid with side phosphate groups of Brevibacterium sp. VKM Ac-2118.

The cell wall of Brevibacterium sp. VKM Ac-2118 isolated from a frozen (mean annual temperature -12 degrees C) late Pliocene layer, 1.8-3 Myr, Kolyma lowland, Russia, contains mannitol teichoic acid with a previously unknown structure. This is 1,6-poly(mannitol phosphate) with the majority of the mannitol residues bearing side phosphate groups at O-4(3). The structure of the polymer was established by chemical methods, NMR spectroscopy, and MALDI-TOF mass spectrometry.

Mineral Transformations in Permafrost‐Affected Soils, North Kolyma Lowland, Russia

Soils in permafrost sediments were studied on the Kolyma Lowland, North‐East Siberia. Mineral transformations were studied by comparing samples from different geochemical positions relative to the permafrost table. The profiles studied are developed from Yedoma deposits (mid to late Pleistocene). Mineralogical composition of study soils is controlled by the illite‐chlorite mineralogy of the parent Yedoma deposits, climatic conditions (extremely cold and dry) and the effect of permafrost. Degradation of illite, weathering of Fe‐containing minerals (chlorite) with further Fe migration within the active layer and its crystallization at the cryogenic barrier in the form of lepidocrocite are the main processes of mineral transformations in the Kriozems studied. The highest concentration of lepidocrocite is associated with the boundary of permanently frozen ground. Geochemical processes are strongly influenced by the permafrost table. The boundary between the seasonally thawing soil and the permanently frozen ground is an important geochemical barrier.

Mineral Transformations in Permafrost-Affected Soils, North Kolyma Lowland, Russia

Mineral Transformations in Permafrost-Affected Soils, North Kolyma Lowland, Russia

Mercury-resistant bacteria from permafrost sediments and prospects for their use in comparative studies of mercury resistance determinants

Mercury-resistant bacteria were isolated from permafrost sediments of Kolyma lowland and Canada existing over five thousand to two million years. Their content was shown to vary within the range 0.001-2.9% and to depend on the amount of mercury in sampling sites (coefficient of correlation 0.75). A collection of mercury-resistant bacterial strains was created. In this collection, various representatives of both Gram-positive bacteria (Bacillus, Exiguobacterium, Micrococcus, Arthrobacter) and Gram-negative bacteria (Pseudomonas, Acinetobacter, Plesiomonas, Myxobacteriales) were identified. Most resistant bacteria were found to contain determinants homologous to mer-operons of contemporary bacteria. The isolated strains of paleobacteria are proposed to be used for a comparative structural study of contemporary and ancient plasmids and transposons carrying mercury resistance determinants.

Phylogenetic diversity of a bacterial community determined from Siberian tundra soil DNA.

Genomic DNA was isolated from the active layer of tundra soil collected from the Kolyma lowland, Northeast Eurasia, near the Arctic Ocean coast. The SSU (small subunit) rRNA genes were amplified with eubacterial primers from the bulk genomic community DNA and cloned into plasmid vectors. Forty-three SSU rDNA clones were obtained, and all of them had different RFLP patterns. Phylogenetic analysis based on partial sequences (about 300 bp) established with the maximum likelihood method revealed the presence of three major and several minor groups that fell into 11 of the established lines of bacteria, and one sequence that could not be assigned to any of the described groups. Most of the clones belonged to the alpha (20.9%) and delta (25.6%) subdivisions of the Proteobacteria, with lesser proportions in the beta (9.3%) and gamma (4.7%) subdivisions, groups typically isolated from soil by culture methods. Fewer than 12% of the clones belonged to Gram-positive bacteria, and 16% of the clones were related to Fibrobacter. The majority of the clones (70%) had sequences that were 5-15% different from those in the current databases, and 7% of the clones had sequences that differed by more than 20% from those in the database. The results suggest that these tundra-derived clones are very diverse in phylogeny, and that many probably reflect new genera or families. Hence, most of the tundra soil bacterial community has never been isolated and thus the physiology and function of its dominant members appears to be unknown.

Atmospheric carbon emission from North Asian Lakes: A factor of global significance

Partial pressures of CO 2 and CH 4 were measured directly or calculated from pH and DIC measurements for 20 lakes on the Yakutian Lowland, North Slope of Verkhoyansky Mountain Ridge, the Kolyma Lowland and in the estuary of the Lena River. Most of the northern landscapes were presented in the sample, which are between the High Arctic (Tiksi area) and the Low Arctic/Subarctic (Chersky area). All limnic waters were supersaturated significantly with respect to the atmospheric pressure of CO 2 and CH 4. The content of CH 4 in High Arctic lakes ranged usually between 10 −1 and 10 −2 μM in the surface layer and between 10 0 and 10 −2 μM in the bottom layer. These values are about 10 2 times lower than in Low Arctic/Subarctic lakes. The partial pressure of CO 2 (PCO 2) ranged usually between 400 and 6000 ppm in the Tiksi site and between 4000 and 20,000 ppm in the Chersky site, although extreme values of PCO 2 reached up to 27,000 ppm in the bottom layer of subarctic thaw lakes. The fall-winter shipboard measurements show that the value of PCO 2 varied significantly from the Bering Sea to the Laptevs Sea. The surface waters of the Laptevs Sea were undersaturated by CO 2, whereas other arctic seas east of the Laptevs seas were slightly supersaturated. The shallow coastal waters from the Laptevs Sea to the Bering Sea were usually 1.5-3-fold supersaturated by CO 2. The shipboard measurement of CH 4 in the arctic seas shows that the concentration of CH 4 was usually less than 0.015 μM. It confirms the previous air-flight data that show a 10–15% increase of CH 4 over land. The analysis of up-to-date experimental results and glaciological data concerning air palaeovariations of CH 4 and CO 2 shows that evolution of the northern lakes might be a significant factor in the present and the past.

Effect of Permafrost and Palaeo-Environmental History on Soil Formation in the lower Kolyma Lowland, Siberia

Abstract Danish Journal of Geography 96: 40–50, 1996. The Geography of soils has been studied in the tundra of the sandy Kolyma Lowland between latitudes 69 ° and 70 ° N. Generally, soils show characteristics indicative of variable intensity of previous fossil Podzol formation in the present day cryoturbated active layer. Hence, the transformation, transfer and segregation of chemical substances in the soil profile can be interpreted as evidence of palaeo-climate changes. Fossil soil features indicate horizon differentiating processes active in a former warmer and wetter climate. The chemical composition reflects a general sequence of pedogenetic translocation processes. Early stages of soil formation primarily involved translocation of weathering products from a carbonic acid weathering system. Inorganic Al-Fe silicate and phosphate materials were translocated into B horizons as the A horizon became more acid. At a later stage the increasing activity of simple organic acids in the A horizons caused a mig...

Some aspects of the impact of climate on the development of thermokarst in the low‐temperature cryolithozone of northern Yakutia

Abstract The authors argue that the main cause for the initiation of thermokarst is local changes in the conditions of heat exchange between ground and atmosphere, e.g., changes in vegetation cover (natural or man‐induced), in snow depth, or in moisture conditions. Climate change is not the immediate initiator of thermokarst but simply provides the background against which these other local changes occur. This thesis is demonstrated with reference to temperature data for Cherskiy in the Kolyma Lowland, taking into consideration increases of varying magnitude in mean annual air temperature, mean summer air temperature, variations in snow depth and varying thermal resistivities of the moss and snow covers. It is further argued that even the Holocene Climatic Optimum could not have induced the development of thermokarst.

New data on late Cenozoic deposits of the Kolyma Lowland

New data on late Cenozoic deposits of the Kolyma Lowland