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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 article presents the generalization results of studying the long-term history of paleofires in the world and on the territory of Russia specifically. Perspective and reliable methods of reconstructing the local and regional dynamics of paleofires – micro- and macro-charcoal analyzes, are considered. In the article, we analyze approaches to the study of paleofires, methods of processing and identifying micro- and macroscopic charcoal particles, including the state-of-the-art software tools for their identification ("The Charcoal Quantification Tool", "WinSEEDLETM") and analysis ("CharAnalysis") based on a review of world and Russian scientific achievements. In addition, the possibilities of modern international paleofire databases (Global Charcoal Database, Reading Palaeofire Database), which contain up-to-date information on local and regional paleofire data in the Holocene, are considered here. The results of the study of paleofires globally and on the territory of Russia in particular are analyzed and possible research directions along with fire reconstruction issues are highlighted. The review of Russian publications has shown that the central and south parts of the East European Plain, as well as the southeast of Western Siberia, are the most studied regions in terms of reconstructing the dynamics of paleofires. Few similar studies were carried out in the Urals Mts., Eastern Siberia and the Far East, but most of the regions of Russia remain understudied in this regard. In recent years, Russian researchers are mainly focused on the study of local fire dynamics based on the use of macro-charcoal analysis. The analysis of international paleofire databases (Global Charcoal Database, Reading Palaeofire Database) shows that these data need to be radically revised in relation to key sites in Russia. The authors present a generalized scheme-map of Russia indicating the key areas where paleofire dynamics were reconstructed using micro- or macro-charcoal analyzes. [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]

Multidisciplinary investigations including geomorphological and geoarchaeological approaches, litho-stratigraphic and pedogenetic analysis accompanied by radiocarbon dating show the contrasting human environmental changes within the highlands of the Russian Altai since the late Paleolithic. Radiocarbon ages of fossil soils formed at 1,475-1,730 m a.s.l. indicate draining of the ice-dammed lake in the Kurai basin before the beginning of the Holocene and disintegration of the Chuya lake into several shallow but quite spacious reservoirs by 8,223 ± 181 cal. BP. Using archaeological sites as spatio-temporal markers allows reconstructions to be specified based on geological data. Archaeological site distribution in the Chuya valley between the Chuya and Kurai basins indicates that all cataclysmic flood events related to the Holocene hydrological changes occurred before the Scythian epoch. Due to the redeposition of most Paleolithic finds in the region, they should be carefully examined before they are utilized for any reconstructions. Using fossil and contemporary soils as an independent informative climatic proxy archive supports the conception of generally more humid and warmer climate conditions in the first half of the Holocene within the SE Altai and a more arid and cold climate in the second one. The repeated climate deteriorations that caused glacier expansion and the progressive aridity intensification in the region along with the sociopolitical reasons are the major factors that controlled the habitat of nomadic communities and cultures shifting within the SE Altai in the second half of the Holocene. Anthropogenic impact together with the progressive aridization led to the deforestation of the eastern part of the Chuya depression. [ABSTRACT FROM AUTHOR]

A core of bottom sediments of 4.98 m depth has been taken from Lake Rubskoe, Ivanovo area (central part of the East European Plain). According to radiocarbon dating, the age of the lower layer of the core is 11 000 cal BP. A study of 23 samples has revealed the remains of 38 taxa of Cladocera (Crustacea: Branchiopoda). According to Lyubarsky's scale, there are no dominant taxa among the cladocerans; Chydorus cf. sphaericus (Müller, 1776) and Bosmina (Eubosmina) cf. longispina (Leydig, 1860) are subdominant taxa. Typical arctic species that had inhabited the lake at the earlier stages of its formation were replaced by taxa that preferred temperate conditions during the development of the water body. Four faunistic zones have been identified on the stratigrhaphic diagram of the cladoceran community of Lake Rubskoe. An increase in the proportion of Bosmina (Eubosmina) cf. longispina in the layers of 8500 cal BP may have been related to an increase of the pelagic area of the water body at that period. In many cases, it is obvious that the rates of certain taxa in the taphocoenosis of Lake Rubskoe correlate with the climatic changes reported at that time. [ABSTRACT FROM AUTHOR]

The problems of diagnostics of the beginning of agrarian development of coniferous–broad-leaved forests in northwestern European Russia and its specificity regarding changes in the zonal forest cover and its anthropogenic modifications inherent in the forest and field-meadow landscape based on studying pollen spectra from key sections. It was established that the onset of the agrarian development of the forests in the region under consideration dates back to 2300–2600 cal years BP. Judging by the continuous presence of cultivated plant pollen in the diagrams, it becomes ubiquitous and irreversible after 1500 cal years BP. The corresponding indicators and plants are given. The presence of plant pollen grains in the diagrams makes it possible to establish the time and nature of agrogenic changes in the vegetation composition. [ABSTRACT FROM AUTHOR]

In the Serteyka River valley in western Russia, eight accumulative fans formed at the mouths of ravines were examined geologically and geomorphologically. The test samples were collected from individual geological drillings made with a manual probe, as well as from excavations in the central and distal zones of the fans. Using the Gradistat program, sedimentological indicators were calculated, i.e. mean grain diameter (MZ), standard deviation (sorting -- σI), skewness (SkI) and kurtosis (KG),and then particle-size distribution frequency curves, cumulative curves and a Passega C/M diagram were drawn. It has been documented that the grain size of the fan sediments depends on the characteristics of the source material. Analysis of sedimentological indicators (mean grain diameter, sorting, skewness, kurtosis) showed the studied fans deposits to have a large variability of erosion and accumulation conditions. For the deposits of younger fans, the 2nd system of the MZ-versus-σI relationship after Mycielska- Dowgiałło (1995) was distinguished, while for the older, the 2nd, 3rd and 4th systems were recognised. The main process of grain transport within these forms was saltation. The ravines on the eastern slope of the Serteyka valley were most likely created in the periglacial period, while the gullies on the western side of the valley developed in the early modern period. [ABSTRACT FROM AUTHOR]

The Holocene evolution of vegetation in the high-plain territory of the northwestern Volga Upland has been shown to have certain specific features. Based on analysis of spore-pollen assemblages from peat deposits, the onset of bog formation has been dated to the late Boreal period (about 8500 yr BP); the pine-birch phase in the development of forests, to the early Atlantic period (8000−6000 yr BP); the appearance and peak development of the zonal broadleaf species complex, to the late Atlantic period (6000−4500 yr BP); and early anthropogenic changes in the vegetation, to about 3000 yr BP. [ABSTRACT FROM AUTHOR]

Despite their huge extent, the peatlands of Russia are an under-exploited source of data on palaeoenvironmental change. We investigated the Holocene history of Staroselsky Moch, an ombrotrophic peatland in the Tver Region of European Russia by analysis of testate amoebae, peat physical properties, plant macrofossils and pollen. The peatland developed through a classic hydroseral succession in the early Holocene with a sharp decline in mineral input to 6200 cal. BC followed by an abrupt transition from fen to bog vegetation around 5500 cal. BC. Through the Holocene, the peatland has accumulated carbon at a mean apparent rate of 21.5 g C m−2 yr−1 suggesting that carbon accumulation rates in peatlands of European Russia lie close to the global average, and contrasting with a short sequence of eddy-covariance data which implies a net loss of carbon. The testate amoeba record shows considerable variability which may be driven by climate, but changes are not well replicated in the macrofossil or pollen data. We tentatively infer (1) a phase of early Holocene warming commencing around 7200 cal. BC, (2) dry peatland surface conditions c. 3700–3900 cal. BC, (3) a shift to wetter conditions from c. 3900 cal. BC, and (4) drier conditions from c. 400 cal. BC onwards. More robust and precise hydroclimatic reconstructions for this region will require the development of a regional transfer function and the replication of results between cores and sites. [ABSTRACT FROM AUTHOR]

Picea pollen abundance (percentage and PAR) was investigated in 23 Tauber pollen traps located in the mixed coniferous-broadleaved forest zone, broadleaved forest zone and forest-steppe zone in the European part of Russia. Modern data were compared with fossil pollen diagrams. In the modern spectra of non-forest zones average Picea pollen percentage is about 1 %, the highest values (up to 3 %) are usually connected with open locations and reflect the regional component of pollen rain. Within the coniferous forest belt average pollen abundance is about 10 %, but this value varies considerably from 1 to 40 % depending on local characteristics of sampling points. The lowest Picea pollen percentages (1 % and less) are observed in the pollen spectra of oligo- and mesotrophic mires, thus the level of 1 % can be significant for Picea and can indicate the continuous range of Picea. For an appropriate interpretation of low Picea pollen abundance in fossil samples the abundance should be analyzed together with other components of the pollen spectra. Large areas of Picea forests are not always reflected in pollen spectra as a high Picea percentage/PAR, as in unfavorable climatic or hydrological conditions the pollen production of Picea forests can be very low. Comparison of fossil and modern pollen spectra shows that a modern analogue of Holocene Picea forests in Central European Russia has not yet been discovered. [ABSTRACT FROM AUTHOR]