Lake Baikal Region Research Articles

Lipophilic Extracts from Needles and Defoliated Twigs of Pinus pumila from Two Different Populations

Hexane extracts of needles and defoliated twigs of Pinus pumila (Pall.) Regel from two distant populations, located in the southwest and the east (i.e., Lake Baikal region and Sakhalin Island) of the species distribution range were studied by GC/MS analysis. Composition and retention indices of major components were determined. A drastic composition divergence for the extracts of P. pumila needles and defoliated twigs, depending on growth location, was established. Needle extracts from the eastern population sample contained mainly labdane-type acids (anticopalic acid derivatives), whereas the predominant components of needle extracts from the other population sample were abietane-type acids (abietic, neoabietic acids) and isopimarane-type diterpenoids (sandaracopimaric acid, sandaracopimaradien-3β-ol). The main components of defoliated twig extracts from Sakhalin Island population sample were abietane-type acids and cembrane-type diterpenoids, while content of these compounds in the extracts of the southwestern marginal population sample was remarkably lower.

Hiking tourism development in protected areas and nature hazard prevention in the Lake Baikal natural territory

Since 2010, recreational development has been permitted in strict nature reserves (zapovedniks in Russia), the most highly protected category of Russian Federal Protected Areas. As zapovedniks comply with the 1b IUCN category for wilderness preservation, human activities within the reserves have been limited and, consequently, there has been little research on the natural hazard impact for tourism. The type of recreational use permitted in the territories and their buffer zones is called Educational Tourism. It is identified as “as a specialized type of ecological tourism where the main goal is an introduction to natural and cultural attractions”. Hiking is seen as one of these suitable types of tourism within the territories of zapovedniks, due to its low impact on natural features. As hiking trails are laid through natural landscapes, it is possible that natural disasters can both damage the infrastructure and cause fatal injuries for visitors. During the planning stages of trail construction, natural hazard monitoring should be conducted. Baikalskii Nature Biosphere Zapovednik in the Lake Baikal region is used as a model territory where scientific research and engineering are employed to better develop hiking tourism. Along with the monitoring of natural processes, several scenarios for trail planning, construction, and maintenance are being analyzed under the threat of mud slides, avalanches and floods.

The Influence of Environmental Restrictions on the Socio-Economic Development of the Lake Baikal Region

The Influence of Environmental Restrictions on the Socio-Economic Development of the Lake Baikal Region

Distribution of soil-inhabiting testate amoebae along a mountain slope (Baikal Lake region, Khamar-Daban ridge, Cherskii peak)

The specific composition and distribution of soil-inhabiting testate amoebae along the Cherskii peak slope (Khamar-Daban mountain ridge, Lake Baikal region) were studied within the altitude range from 1000 to 1570 m above sea level according to the changes in biogeocenoses from birch-aspen to cedar-fir forests to cedar-fir-bush forest-tundra. One-hundred-four taxa were identified. The most common species are ubiquits with a wide geographical distribution: Trinema lineare, Euglypha levis, Euglypha rotunda, Trinema enchelys, Phryganella acropodia, Tracheleuglypha dentata, Assulina muscorum, Trinema complanatum, and Centropyxis aerophila. The species richness varies from 12 to 40 species per sample, and the abundance varies from 500 to 120000 ind. per gram of absolutely dry soil. The spatial heterogeneity of the specific composition grows with altitude, and the community composition changes. The absence of a common pattern in the cenotic changes in the communities of testate amoebae in Western Europe and the Lake Baikal region is discussed.

Late Glacial and Holocene environmental change reconstructed from floodplain and aeolian sediments near Burdukovo, lower Selenga River Valley (Lake Baikal region), Siberia

Floodplain and aeolian sediments near Burdukovo reveal a detailed record of Holocene environmental change in the lower Selenga River Valley (Lake Baikal region, Siberia). During the late Pleistocene and early Holocene fine-grained alluvium accumulated on the floodplain followed by a period of increased landform stability and subsequent pedogenic formation. This part of the stratigraphical sequence yielded rich assemblages of terrestrial molluscs, which increase in species diversity from early pioneer communities with about ten taxa to levels containing over twice that number. The land snail assemblages also record an episode of relatively drier local habitats prior to ∼9.2 ka BP with subsequent wetter conditions lasting until ∼8.0 ka BP. This was followed by an abrupt and sustained change in floodplain deposition, shifting from overbank alluvium to aeolian sedimentation, within which a series of weakly developed soil horizons formed during the middle and late Holocene periods. The onset of aeolian processes and relatively drier conditions in the middle Holocene at Burdukovo coincides with major changes observed both in other regional palaeoenvironmental proxy records and in local archaeological sequences, although it is still not clear how the two are linked.

Aeolian records of abrupt environmental changes in southern Siberia during Middle-Late Holocene based on the research in the Lake Baikal Region

Aeolian records of abrupt environmental changes in southern Siberia during Middle-Late Holocene based on the research in the Lake Baikal Region

Vegetation dynamics around Lake Baikal since the middle Holocene reconstructed from the pollen and botanical composition analyses of peat sediments: Implications for paleoclimatic and archeological research

The present paper summarizes the current evidence of natural changes in the forest and forest-steppe areas of the Lake Baikal Region (LBR) since ca. 7 cal ka BP, covering the period from the late Neolithic to the present time. To reconstruct local to small-regional scale vegetation changes and their probable causes during this period, pollen content and peat botanical composition were analyzed from three radiocarbon-dated peat sections, located near Lake Baikal. For better understanding of the local and regional environmental history and climate variability during the middle and late Holocene, the results are compared with published environmental records from lacustrine and mire sediments from the LBR and from elsewhere. The comparison confirms the earlier interpretations that the middle and late Holocene vegetation dynamics in the LBR was primarily driven by natural forcing and likely was associated with large-scale circulation processes controlling the regional water balance rather than with human activities. Some synchronous changes in environmental and archeological data likely point to a possible causal link between past climate changes and the cultural history of the region. The Kuchelga (53°00′57″N, 106°44′49″E), Ochkovoe (51°26′05″N, 104°38′57″E) and Cheremushka (52°45′09″N, 108°05′50″E) peat records represent three different climatic regions around Lake Baikal and demonstrate that the environments and vegetation of the drier western coast were more sensitive to the climate oscillations of the middle and late Holocene in comparison to the more humid areas east, and particularly south of Baikal. Therefore, it could be expected that environmental impact on early human societies was strongest in the arid region to the west of Lake Baikal. To test this hypothesis, however, accurately dated multi-proxy records of the Holocene climate and environments from this so far poorly studied region are absolutely necessary.

Recent weakening of northern East Asian summer monsoon: A possible response to global warming

We investigate the possible causes of the weakening of northern East Asian summer monsoon (EASM) from 1954 to 2010. We found that the decreased intensity of northern EASM as measured by a circulation index (EASMI) is significantly correlated with the increase of the surface air temperature (SAT) averaged over the Lake Baikal region (45°–65°N, 80°–130°E) defined as SATI. Corresponding to increasing SATI, an anomalous low‐level anticyclone occurs with northeasterly prevailing over northern East Asia (30°–50°N,100°–130°E), resulting in a weakened southwesterly monsoon winds and drier climate in this region. Numerical experiments with the community atmosphere model version 3 (CAM3) show that the joint forcing induced by greenhouse gases (GHG), sea surface temperature (SST), solar radiance (SR), and volcano activity (VC) can replicate the observed trend of SATI and its related circulation anomalies, but without GHG forcing the model failed to simulate the warming trend of SATI after 1970s. This implies that the global warming is likely responsible for the local warming around the Lake Baikal, which in turn weakens the northern EASM in recent decades.

A rare naviculocuneiform I coalition from Bronze Age Siberia

Naviculocuneiform coalitions are among the least common types of tarsal coalition, a rare congenital anomaly characterized by incompletely separated tarsal bones. Only a handful of cases have been documented from the archaeological record, none of which have been recovered from north central Asia or date to earlier than about 2000 years B.P. Here, we present a case of nearly complete osseous coalition of the left navicular and cuneiform I from the early Bronze Age (ca. 5200/5000–4000cal. BP) Lake Baikal region of Siberia (Russian Federation). We also provide substantial evidence for the congenital (rather than acquired) basis of this unusual condition and discuss, using modern clinical data, possible intra vitam complications.

Late Quaternary geology of the Tunka rift basin (Lake Baikal region), Russia

The objective of this research is to obtain a better understanding of the evolution of the Tunka rift basin, part of the Baikal rift zone, and how it relates to the overall geologic history of the region, particular for the Quaternary period. The tectonically active Baikal rift zone began forming over 50million years ago and continues today. In the Tunka basin, during the Oligocene and Middle Pliocene, relatively weak tectonic disturbances took place and thick accumulations of organic-rich sands, silts, and clays were deposited in lacustrine–marshy subtropical environments. Tectonism increased between the Miocene and Pliocene and thick units of coarse alluvium and floodplain sediments were deposited. During the Late Pliocene–Quaternary, tectonism formed basins that are now filled with a variety of coarse clastic materials. Early and Middle Pleistocene sediments are poorly exposed, covered by widespread Late Pleistocene deposits. Three Late Pleistocene sedimentary facies dominate: boulder–pebble gravels (proluvial, glacial fluvial, and alluvial sediments), alluvial sand, and loess-like sediments with associated slope deposits altered by post-depositional wind erosion. The relationship between these complexes, including radiocarbon and other chronological data and fauna and flora remains, indicates that they began forming c. 70000yr ago. Paleosols, glacial deposits and cryogenic material indicate that at times the climate was cool or cold. During the early Late Pleistocene renewed tectonism took place causing increased deposition of coarse sediments. The middle Late Pleistocene deposits consist mostly of sandy, floodplain alluvium. By the end of the Late Pleistocene–Holocene, alluviation was reduced and replaced by a high degree of erosion and aeolian deposition.

External forcing factor reflected in the common signals of δ18O-tree-ring series of Larix sibirica Ledeb. in the Lake Baikal region

A set of δ18O-tree-ring series obtained from larch trees growing in three different ecotopes near Lake Baikal are analysed together with the relevant meteorological data. It has recently been proposed that the external forcing factor, as a characteristic of the total investigated territory, must cause a certain similarity of the essential properties of the simple processes induced by this forcing. The similarity is the main point of this investigation and is the basis for a constructive definition of the intersection of the sets of these induced processes as data sets. We specify the elements of the intersection of the sets as the “common signals” for each process (set). The common signals are computed by a new algorithm of “co-filtering”, which is based on the trigonometric Fourier transform. We call the output of this algorithm the “co-filtered common signals” (CCS).We discovered that the CCS gave substantial contributions to the variances of the initial isotope series, which are more weakly correlated than their CCS. Next, we found that synchronous variations of the CCS of the temperature and precipitation for April–May and June–August induce synchronous variations in the CCS of the δ18O-tree-ring series. Furthermore, the characteristics of such synchronism vary with time.We concluded that the CCS of the δ18O-tree-ring series clearly express the external forcing factor even when there are significant differences in the vegetation conditions.

The structure of the plant communities in the different environment contact sites on the base of the soil-geobotanic profiling in the changing climate of Lake Baikal region

The results of studies of the peculiarities of formation of phytocenoses in environments contact sites of the western and eastern coasts of the Lake Baikal has been showed in this paper. On the base of geobotanic profiling combined with soil one, the structure and dynamics of phytocenoses forming under the conditions of mutual development of light-coniferous taiga forest and of extra zonal steppes. Edaphic conditions and placement of phytocenoses are main trigger factors determining the ways of plant cover development in this part of Lake Baikal basin. We discuss the characteristics properties inherent in the linkage of the dynamics and spatial variability of the vegetation with the change of climate in the Baikal region. The regional conditions of the physiogeographic environment had given rise to structurally highly contrasting plant communities in this region. The increase in yearly mean summertime amounts of rainfall, combined with the rise of yearly mean winter temperatures over the last years were conducive to changes in the spatial structure of vegetation. The boundary between the types of vegetation undergoes smoothing. The upper boundary of forest is altered because of changes of the environment that are responsible for the zonality and properties of vertical zonality of the vegetation on the mountains surrounding Lake Baikal. Changes in the vegetation serve as indicators of climate change as well as providing diagnostic tools for the genesis of the Baikal region’s natural environment.

Public information: The shifting roles of minority language news media in the Buryat territories of Russia

In ‘multinational states’ such as the former Soviet Union and contemporary Russian Federation, minority language media have been developed for diverse ends. This article examines the changing roles of minority language news media over a century of language shift in the Lake Baikal region, where generations of Buryat speakers have been shifting to Russian. Drawing on archival materials and ethnographic research with media personnel and audiences, I show how linguists, journalists, and policymakers have directed minority language media practices in response to their own shifting conceptions of an existing, emergent, or contracting Buryat language public—and of media’s ideal or actual relationship to it.

A reassessment of late glacial – Holocene diatom oxygen isotope record from Lake Baikal using a geochemical mass‐balance approach

AbstractWe present a new palaeoenvironmental record of hydrological variability in Lake Baikal, based on re‐modelled δ18Odiatom values of diatom silica (δ18Omodelled), where the residual contaminants are identified and compensated for using electron optical imaging and whole‐sample geochemistry. δ18Omodelled interpretations are based on the balance between rivers with high δ18O values and rivers with low δ18O values. Isotopic variability is related to latitudinal differences in precipitation which feed these rivers. The δ18Omodelled record suggests that rather moist conditions prevailed in the Lake Baikal region during the latter stages of the Younger Dryas. Throughout the Holocene, episodes of low δ18Omodelled values are, in general, in good agreement with increases in percentage haematite‐stained grains in North Atlantic sediments (indicative of ice‐rafted debris events). Rivers with southerly catchments dominate fluvial input especially between c. 3.3 and 2 cal ka BP, concurrent with high precipitation in the Lake Baikal region. Copyright © 2011 John Wiley & Sons, Ltd.

Long-term dynamics of Lake Baikal pelagic phytoplankton under climate change

The effect that climate change in the Lake Baikal region has on the state of the lake plankton is discussed. The increase in water temperature in the photic layer and chlorophyll a content during direct stratification is demonstrated with the use of a database containing the results of plankton observations from 1951 to 2000. The number of small-cell algae belonging to the summer complex seems to increase, while the number of endemic large cell algae developing under the ice is characterized by negative trends.

Presence and genetic diversity of microcystin-producing cyanobacteria (Anabaena and Microcystis) in Lake Kotokel (Russia, Lake Baikal Region)

A survey was conducted for the presence of cyanobacteria toxins in Lake Kotokel due to a few cases of Haff disease registered in 2008–2009 caused by consumption of fish from Lake Kotokel, and wildlife mortality including large fish kill. The aims of this study were to determine what cyanotoxins (if any) were present in the lake, to describe phytoplankton composition including morphology, density, and species diversity of cyanobacteria, as well as to evaluate the trophic state of the lake. Samples were collected from both nearshore and central sites in August of 2009. Aphanocapsa holsatica dominated the phytoplankton. The presence of toxigenic genotypes of Microcystis spp. and Anabaena lemmermannii was detected by sequencing of PCR-amplified aminotransferase domain of microcystin synthetase gene. LR, RR, and YR microcystin (MC) variants were detected with liquid chromatography-UV mass spectrometry. The data do not shed light on the etiology of Haff disease in Lake Kotokel region, nevertheless taking into account the recreational importance of the lake and its direct connection to Lake Baikal, a necessity to monitor cyanobacteria in these water bodies is evident. This is the first report on simultaneous detection of MC-producing genotypes and MCs in the Lake Baikal region.

Late Pleistocene and Holocene environmental peculiarity of the Baikalian region, based on mammal associations and deposits

Changes of paleoclimates and paleoenvironments in the Lake Baikal region (including Transbaikalia and Prebaikalia) are traced through the Late Pleistocene-Holocene on the basis of small mammal faunal succession, the deposit structure and pollen assemblages. Paleoenvironments and biota of the two regions became increasingly different since the end of Middle Pleistocene. In Prebaikalia, tundra-steppe (non-analog) faunas appeared and were dominant through the Late Pleistocene, although there was alternation of faunas indicative of colder and warmer (interglacial) conditions. In the Transbaikalian region, faunas typical of arid landscapes were characteristic of both cold and warm periods. They were similar in the species composition, although differing noticeably in proportion of individual taxa.

Genesis and properties of black soils in Buryatia, southeastern Siberia, Russia

Soils with deep and dark brown to black humic surface horizons, derived from sandy-silty aeolian and alluvial sediments, are relatively fertile and store huge amounts of carbon. Globally, they mainly correlate with steppe ecosystems. Because their deep and dark epipedons are frequently rich in Black Carbon, it was recently suggested that they developed due to prevalent burning of the semiarid vegetation. This paper describes six soils with deep and dark humic surface horizons, located in catchments of the Selenga and Uda rivers in Buryatia, southeastern semiarid Siberia. The organic matter of most of these soils not only originates from grass steppe, but in addition from trees and shrubs. Five soils can be classified as Chernozems and Kastanozems ( WRB, 2006); one soil is a deep and black Anthrosol, occurring in patches in the region. All soils have calcic horizons below the mollic epipedon, some with cambic Bw horizons in between. As the parent material does not contain carbonates, aeolian input and hydrolysis of Ca-silicates contribute to the development of the secondary carbonate accumulation, which is frequently cryoturbated. All profiles are more or less stratified due to solifluction. Texture ratios (<6.3/63-2000 μm) show maxima in the dark A horizons, indicating advanced paedogenesis. This is supported by weathering proxies, including SiO 2/Al 2O 3 and Al 2O 3 × 100/Al 2O 3 + Na 2O. Increased concentrations of TiO 2, MgO and Fe 2O 3 presumably indicate advanced formation of chlorite. Radiocarbon analyses indicate that these deep and dark mollic horizons started to develop during the more humid-Holocene Climatic Optimum, ca. 7000–5000 BP. Palynological studies confirm expansion of forests in the Lake Baikal region in this period. This is in agreement with higher alkane ratios nC27/nC31 in most of the deep and dark A horizons, indicating that these epipedons, diagnostic for Chernozems and Kastanozems, did not develop exclusively under grass steppe, thus supporting the hypothesis that a significant part of the soil organic matter is inherited from trees and shrubs. This seems to be in contrast to Middle Europe and the Russian plain where Chernozems presumably developed during the early and mid-Holocene under grass steppe and subsequent degraded with increasing humidity and invasion of forests. High contents of Black Carbon in the Calcic Chernozem P4 and lower ones in the long-lasting occupied Hortic Anthrosol indicate that the deep and dark A horizons of Mollisols most likely do not result from frequent burning, but from biochemical processes.

A review of the Mesozoic turtles of the Junggar Basin (Xinjiang, Northwest China) and the paleobiogeography of Jurassic to Early Cretaceous Asian testudinates

Middle Jurassic to Early Cretaceous sediments exposed in the Junggar Basin have yielded a rich turtle assemblage. Jurassic taxa include the purportedly basal turtle Sichuanchelys sp. and at least six basal eucryptodires, which are currently united in the likely paraphyletic taxon “Xinjiangchelyidae.” Early Cretaceous assemblages, by contrast, include a single “xinjiangchelyid” and a single potential pantrionychian, but are otherwise dominated by more derived eucryptodires, currently grouped in the paraphyletic taxon “Sinemydidae”/“Macrobaenidae.” Comparison of the Junggar turtle assemblage with those of coeval Asian localities reveals that Jurassic turtle assemblages were rather homogenous throughout the Jurassic, but split in the Early Cretaceous. In particular, the Early Cretaceous Junggar turtle assemblage resembles those of other northern Chinese provinces, Mongolia and the Lake Baikal region of Russia in their retention of rather basal turtles, whereas all other Asian localities are dominated by more derived eucryptodires, particularly pantrionychians. This chasm may be the result of biogeographic, ecological and climatic conditions, where dry conditions in isolated inland basins created an ephemeral lake habitat optimal for basal eucryptodires, whereas the river environments typical of the surrounding coastal areas were favourable for more derived eucryptodires.

Last glacial–interglacial vegetation and environmental dynamics in southern Siberia: Chronology, forcing and feedbacks

Radiocarbon-dated pollen and diatom records from Lake Kotokel in southern Siberia help to reconstruct the environmental history of the area since ~ 47 kyr BP. Pollen spectra composition and reconstructed biome scores suggest predominance of a tundra–steppe vegetation and variable woody cover (5–20%) between ~ 47 and 30 kyr BP, indicating generally a harsh and unstable climate during this interval, conventionally regarded as the interstadial within the last glacial. The short-term climate amelioration episodes in the glacial part of the records are marked by the peaks in taiga and corresponding minima in steppe biome scores and appear synchronously with the hemispheric temperature and precipitation changes recorded in the Greenland ice cores and Chinese stalagmites. Transition to full glacial environments occurred between 32 and 30 kyr BP. The interval at ~ 30–24 kyr BP was probably the driest and coldest of the whole record, as indicated by highest scores for steppe biome, woody coverage < 5%, absence of diatoms and reduced size of the lake. A slight amelioration of the regional climate at ~ 24–22 kyr BP was followed by a shorter than the previous and less pronounced deterioration phase. The late-glacial (~ 17–11.65 kyr BP) is marked by a gradual increase in tree/shrub pollen percentages and re-appearance of diatoms. After 14.7 kyr BP the climate became warmer and wetter than ever during ~ 47–14.7 kyr BP, resulting in the deepening of the lake and increase in the woody coverage to 20–30% ~ 14.5–14 kyr and ~ 13.3–12.8 kyr BP. These two intervals correspond to the Meiendorf and Allerød interstadials, which until now were interpreted as part of the undifferentiated Bølling/Allerød interstadial complex in the Lake Baikal region. The increase in tundra biome scores and pronounced change in the diatom composition allow (for the first time) the unambiguous identification of the Younger Dryas (YD) in the Lake Baikal region at ~ 12.7–11.65 kyr BP, in agreement with the formal definition and dating of the YD based on the Greenland NGRIP ice core records. The maximal spread of the taiga communities in the region is associated with a warmer and wetter climate than the present prior to ~ 7 kyr BP. This was followed by a wide spread of Scots pine, indicating the onset of modern environments.