Search

The paper presents isolation basin stratigraphy in bottom sediments from nine lakes in the Teriberka area on the Kola Peninsula, northwestern Russia. Isolation contacts in these basins, identified from lithological and diatom analysis, were used together with 25 radiocarbon dates, to construct a relative sea-level (RSL) curve for the Holocene. Records of marine water re-influx were found in the sediment sequence from one lake, located at c. 17 m a.s.l. The re-influx of marine water seems to be caused by the mid-Holocene (Tapes) transgression and tsunami event. The RSL curve indicates several phases in the postglacial evolution of the Kola coast. An early phase of rapid sea-level fall of c. 32 m around 11,500 cal yr BP, at a rate of c. 40 mm per year, corresponds to glacio-isostatically induced emergence following deglaciation at the Younger Dryas and beginning of the Holocene. In the time interval between c. 11,000 and 7600 cal yr BP, either a stillstand or a slight rise in relative sea level, cresting at about 21 m a.s.l., is suggested in the Teriberka area. This is followed, after c. 7300 cal yr BP to the present day, by a slow glacioisostatic emergence with an average rate of about 2–3 mm per year. [ABSTRACT FROM AUTHOR]

Peatlands store massive amounts of organic carbon, but the fate of this carbon remains unclear as global climate continues to warm. The age of peatland inception and the main drivers of peat initiation are one of the most important issues in Holocene paleoecology, especially for the numerous but under investigated peatlands in European Russia. This paper introduces new peatland initiation ages for 44 mires in three areas located in the central part of European Russia within the Polesie landscape belt. This region is characterised by waterlogged sandy plains and flat surface topography. Phases of peatland initiation were compared with Holocene fire regime derived from macro-charcoal data as well as with regional climatic reconstructions. We found that peat inception in the region started around 12,000 cal yr BP, but the most active phases of peatland initiation took place during the periods 8500–7500, 7000–6000, 5300–5800, 4000–3500 and 1700–1200 cal yr BP. Expect for rapid peat growth during the early Holocene, peatland initiation mostly coincided with warm climatic periods and increased fire frequency. Forest soil paludification in poorly drained Polesie landscapes was presumably enhanced by reduced evapotranspiration and changes in water balance due to disturbance of forest cover after wildfires. We expect that rising air temperature in the current century will cause higher fire frequencies and may encourage waterlogging of forests and ecosystem transformation. [ABSTRACT FROM AUTHOR]

This paper presents the results of pollen, diatom, charcoal, and sediment analyses from Lake Bol'shoye Zavetnoye, situated between the Gulf of Finland and Lake Ladoga on the Karelian Isthmus, north-western Russia. The main goal is to contribute to the discussion of Neolithic land use in north-eastern Europe. The article aims to answer questions related to Stone Age hunter-gatherer economy, ecology, and anthropogenic environmental impact through a comprehensive combination of multiple types of palaeoecological data and archaeological material. According to diatom data, Lake Bol'shoye Zavetnoye was influenced by the water level oscillations of Ancient Lake Ladoga during much of the Holocene. Intensified human activity and prolonged human occupation become visible in the Lake Bol'shoye Zavetnoye pollen data between 4480 BC and 3250 BC. During the final centuries of the Stone Age, a new phase of land use began, as several anthropogenic indicators, such as Triticum, Cannabis, and Plantago lanceolata appear in the pollen data and a decrease in Pinus values is recorded. In general, the results indicate that socio-cultural transformations could have taken place already from the mid-5th millennium BC onwards, including new ways of utilizing the environment, perhaps also in the field of subsistence, even though the livelihood was based on foraging throughout the period. [ABSTRACT FROM AUTHOR]

This paper presents the results of geological, geomorphological, geochronological investigations and the analysis of the biological composition of deposits within the high-mountainous Boguty river basin. The main stages of landscape evolution during the last 14 ka have been investigated through 32 radiocarbon dates. The area is located in the most arid southeastern part of Russian Altai and constitutes the eastern periphery of the Chuya intermountain depression, and the western side of the Chikhachev range. Postglacial landscape development of the upper reaches of the Chuya River began from the degradation of its vast glaciation. By 14 ka cal BP the glaciers had either completely melted or retreated above 2500 m above sea level. As a result, numerous lakes occupied open places and five types of these basins can be seen in the modern topography. They are large moraine-dammed lakes connected with the Boguty River, while some basins have been dammed by uplifted tectonic blocks and numerous lakes are of thermokarst origin or are small cirque lakes and temporal lakes fed by seasonal meltwater from meteoric, ground water and permafrost degradation. Large moraine-dammed lakes within the Boguty basin were developed before the Holocene. The water filling these basins was controlled by the height of moraine dams and by the depth of the Boguty river incision. The moraine-dammed Low Boguty Lake formed earlier than 10 ka cal BP. Its partial draining and transformation of littoral zone into peat bog took place about 8.2-7.6 ka cal BP. As a result of the analysis of biological composition, four stages of water level fluctuations in the lacustrine-boggy system were recognized. The specific geomorphic and sedimentary features in the middle part of the Boguty basin determined the recurrence of debris flow events at about 8-7; 2.9-1; 0.65 and 0.3 ka cal BP, but the last event occurred in June 2017. The occurrence of fossil forest soils dating to about 11-8.5 ka cal BP and of charcoals (Larix sibirica Ledeb) of about 8.5-7.8 ka cal BP indicate a prolonged period of developing forest vegetation in the Boguty basin, which is currently treeless. In general, the data suggest that in SE Altai the climate in the first half of the Holocene was warmer and more humid in comparison with the modern one. The second half of the Holocene has been characterized by colder climate conditions accompanied by aridity intensification, which became especially pronounced during the last 2-1.5 ka. [ABSTRACT FROM AUTHOR]

Abstract The paper presents new pollen and plant macrofossil records of environmental changes at the southern boundary of the mixed coniferous-broadleaf forest zone in the north-western part of the Mid-Russian Upland (central European Russia) during the middle and late Holocene. The obtained results show that, between 7000 and 5000 cal yr BP, the study area was situated in a wooded steppe vegetation zone and the boundary between forest and steppe biomes was disposed of 50–70 km further north-west in comparison to its present position. After 5000 cal yr BP the more humid climate conditions resulted in the expansion of broadleaf forests, which persisted in the study area until 2000 cal yr BP. Therefore, the pre-agrarian landscape of these regions was mixed broadleaf forests of Quercus, Tilia, Ulmus and Corylus. Since around 2000 cal yr BP, human activity has been increasingly dominant with enhanced burning, soil erosion, felling of trees and the rise of agriculture. During the last three centuries, human activity resulted in a strong landscape transformation. Nowadays the remnants of the primary forest vegetation are persisted in small locations only. [ABSTRACT FROM AUTHOR]

Abstract Using the territory of the Orlovskoye Polesye National Park as a case study within the catchment basin of the Oka River (Mid-Russian Uplands, Oryol Region, Russia), we obtained palaeoecological data for studying response of forest landscapes within the forest-steppe ecotone to climate change and human impact through the Late Holocene. The paper presents reconstruction of environmental change on a local to regional scales based on plant macrofossil, spore-pollen and testate amoeba records from a peat core along with reconstruction of woodland coverage inferred from pollen data. Over the past 4000 years, the total woodland coverage has fluctuated insignificantly, ranging from 38 to 52%, while the structure of the forest has changed radically. Prior to 1500 cal. yr BP, both birch-pine and mixed temperate deciduous forests of oak, elm, ash and lime with Scots pine and well-developed shrub understory of hazel and alder grew in the region. The subsequent agricultural colonization of the territory led to a reduction of a broadleaved trees in forest stands since 1500 cal. yr BP. During the last few centuries, human activity largely associated with cutting/burning trees and farming favored the expansion of secondary forests dominated by birch. [ABSTRACT FROM AUTHOR]

This paper presents the results of paleoseismogeological investigations including tree-ring analysis and radiocarbon dating in pleistoseist zone of the 2003 Chuya earthquake, SE Altai, Russia. Twenty-five radiocarbon dates of previously unknown evidences of prehistoric earthquakes along the fault bounders of the Chagan-Uzun massif, North Chuya and South Chuya ranges are reported. Perspectives of applying dendroseismological approach within the high mountainous seismically active southeastern part of Russian Altai are demonstrated. In addition to estimating the germination ages of trees growing on the bare surfaces of seismically triggered landslides, analysis of wood penetrating injuries in the individual tree ring series was applied for dating paleorock-falls. Analysis of distribution patterns of tree-ring anomalies and injured trees suggests a criterion of recognizing seismic origin of past rock-falls. Dendrochronologically obtained dates of abrupt intensifications of rock-falls can be considered as supposed dates of past earthquakes, which should be verified by alternative proxy data. Obtained results argue for the high regional seismicity in the second half of the Holocene. Strong earthquakes occurred here AD 1532, and 600-700, 1300-1500, 2400-2700, 3400-3700, 3800-4200 cal BP. This data clarifies the chronology of seismic events within the SE Altai. The specified recurrence interval of strong earthquakes is about 400 years during the last 4000 years. [ABSTRACT FROM AUTHOR]

In this paper all the Stone Age and Early Metal Period (ca. 8600 cal BC - 300 AD) radiocarbon dates from the Karelian Isthmus, Russia, are compiled and their archaeological usability assessed using a set of evaluation principles. The quality of radiometric dates from such a large area has rarely been methodologically examined in Finnish or North-West Russian archaeology, and is applied here for the first time on the present material. Special attention is given to the discussion on the deficiencies and limitations of the current data. Based on the 81 dates evaluated as useful, a tentative radiocarbon chronology is presented for the study area. This is generally in sequence with the chronologies of the nearby areas, but suggests some differences especially towards the end of Stone Age, as well as the presence of biases caused by taphonomic and research-related factors. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents the first paleontological data (pollen, plant macrofossil, diatom and ostracod) on the sediments of Lake Beloye, which is situated in the forest-steppe zone of Western Siberia. Our study contributes to better understanding of the Middle–Late Holocene regional to local environmental changes. Regionally, we recognized a cold stage of 3.4–2.3 calibrated ka BP and a dry stage of 2.8–1.7ka BP. The dry stage coincides with the climate-driven lowered level of the lake at 2.6–1.5ka BP. Later, the climate changed to warmer and wetter, which resulted in a highest stand of the lake at 1.3–0.2ka BP and was followed by the lowering of the lake. Forest-steppe persisted in this area during the whole period under consideration, but probably shifted southward. Such a shift is reflected in the environment around Lake Beloye similar to that of modern taiga, which existed at 3.2–1.3ka BP, however, compared to the colder and wetter climate of taiga, the conditions were colder and drier. The local plant associations and the lake ecosystem were affected by those events of climate and lake level changes. The initial eutrophic sedge-reed swamp evolved to the oligo-mesotrophic sphagnum bog, which existed around the lake at 3.2–1.3ka BP. Later, the bogging process was interrupted by the lake transgression, after which the dried bog around the lake was occupied by the birch forest. The lake ecosystem was strongly affected by the 3.4ka BP climate change: the low-alkaline eutrophic lake with abundant water higher plants and diatoms changed to the alkaline oligotrophic lake with calcium-fixing macrophytic algae and angiosperms. This resulted in total change of lake''s bio-geochemical and sedimentation patterns. [Copyright &y& Elsevier]

The primary aim of this paper is to describe and discuss the palaeoclimatic significance of mid- to late-Holocene fields of raised-beach ridges at Matalaniemi and sea-ice-pushed boulders at Kutovaya Bay on the Kola Peninsula. These beach features are interpreted as indicating at least 12 periods of stormy conditions alternating with calmer periods of relatively low sea-surface temperature since about 8000 cal. BP. A consistent chronology of climate change is difficult to establish due to considerable uncertainties attributed to local beach processes and relative sea-level displacements. A tentative interpolated chronology is suggested. At present, terrace formation at Matalaniemi and the absence of sea ice at Kutovaya Bay indicate an intermediate windy and mild type of winter climate. [ABSTRACT FROM AUTHOR]