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The paper presents the results of comprehensive (microprobe, paleomagnetic and magnetic) studies on peats from the Tyapka peat section (Russian Far East). Radiocarbon dating placed the start of peat formation at ∼11.7 ky B.P. The principle carriers of magnetization were found to be magnetite, to a lesser extent hematite and, possibly, greigite. The relative paleointensity values obtained through calculations are in good agreement with the literature data. Intervals with negative inclinations of the magnetization vector were identified in peats, which most likely correspond to geomagnetic excursions in the Holocene. The research constrained the duration of the geomagnetic excursions, as well as the geomagnetic field intensity behavior not typical for such variations. [ABSTRACT FROM AUTHOR]

The paper presents new paleobotanical data in combination with the results of radiocarbon dating obtained from organomineral deposits of the northern shore of Pechevalavato Lake (70°13′22.3″ N, 71°50′57.6″ E) in the Seyakha River basin and characterizing the dynamics of vegetation in the northern part of Central Yamal in the Holocene. It has been shown that a tree birch (Betula sect. Betula) grew in Yamal in the early Holocene (10.2–8.7 cal kyr BP) no less than 400 km north of the modern northern limit of distribution of Betula pubescens ssp. tortuosa. Favorable conditions for the existence of birch woodlands at this time were provided by a higher temperature of the growing season, exceeding the modern parameters of the warmest month of the summer season by approximately 3–4°C. At the end of the early Holocene (after 8.5 cal kyr BP), forest vegetation began to degrade, and open landscapes with diverse plant communities of the subarctic tundra and single trees in the river valley spread. About 6.5 cal kyr BP, the northern subarctic tundra began to form the zonal appearance of the study area in climatic conditions close to modern ones. [ABSTRACT FROM AUTHOR]

This paper describes an approach assuming that already in the sea, based on the express analysis of visually similar cores of Arctic Holocene sediments and their comparison with dated and studied in detail cores of the regional sediments, it is possible to select a material that is promising for sequence stratigraphic correlation and paleoreconstructions. The range of lithological, colorimetric (CIE L*, CIE a*, and CIE b*), geophysical (magnetic susceptibility), and geochemical (Fe/Rb, Mn/Rb, and Ti/Rb) parameters is analyzed. The most informative characteristics include the CIE b* color coordinate, magnetic susceptibility, and Fe/Rb. [ABSTRACT FROM AUTHOR]

In this paper we restore moisture changes since the Younger Dryas based on the study of diatom flora in sediments of the Zelenyi coastal paleolake, the Lesser Kuril Ridge. The section includes numerous interlayers of tephra, the sources of which were located on the islands of Kunashir and Hokkaido, and interlayers of tsunamigenic sands, which made it possible to determine the impact of catastrophic events on changes in the ecological situation. The stages of the development of the lake are identified and its evolution is analyzed during short-period climatic rhythms. The reservoir had its maximal depth at the beginning of the Holocene, and planktonic forms predominated among diatoms. Three phases when the lake turned into a lagoon were established, and the erosion of the barrier form most likely caused this during large tsunamis associated with earthquakes. Except for these cases, the main factor leading to the change in lacustrine–marsh environments was climate change. We identified relatively dry periods and wet periods associated with an increase in the intensity of cyclogenesis in the South Kurils region. We correlated with high-resolution paleoclimatic records from archives for the Southern Kuriles; the most striking events were compared with data for Sakhalin and the continent. Changes in moisture on the islands and the margin of the mainland in the Middle–Late Holocene were established to be in antiphase in most cases, except for the cooling of 2800–2500 BP and the Little Ice Age. The connection of regional climatic changes with anomalies in the ocean and atmosphere of the Asia-Pacific region is shown. [ABSTRACT FROM AUTHOR]

Sediments from a small lake, Loch Beag, in Barrees, Beara peninsula, south-western Ireland, provide a record of vegetation history that spans most of the Lateglacial and Holocene (14–0.43 ka). The detailed part of the record relates to the Holocene, which is the focus of this paper. The investigations carried out include pollen and macrofossil analyses, loss-on-ignition measurements and 14C dating. As well as providing records for tree and shrub taxa, and especially Pinus, Quercus, Ulmus, Fraxinus and Taxus, other taxa mainly with Atlantic and/or Lusitanian distributions are also considered. These include Arbutus unedo (strawberry tree) and fern species such as Osmunda regalis, and the filmy ferns Hymenophyllum tunbrigense, H. wilsonii and Trichomanes speciosum (Killarney fern). Detailed records for a suite of bog/heath taxa, including ericoid species (Erica tetralix and E. cinerea), Narthecium ossifragum, Hypericum elodes and Myrica gale, are presented. The results of 14C dating of bog-pines from western Ireland are summarised. Results of other investigations, including key Holocene pollen diagrams, and charcoal and fossil-wood records from archaeological excavations that relate mainly to the Bronze Age in the wider west Cork/Kerry region, are reviewed. Vegetation dynamics, human impact and plant biogeography are discussed in the light of the considerable data now available for the region. [ABSTRACT FROM AUTHOR]

This paper considers mass materials related to the feeding of the eagle owl from three latitudinal regions of the Urals (northern and southern taiga and steppe). All collections were carried out in the same type of location of bone remains of prey from pellets at the nesting grounds of eagle owls in niches and caves at cliffs along riverbanks. The prey of the eagle owl is divided into three categories: main, alternative, and concomitant. The paper shows the degree of correspondence of the proportions of individuals of different species and their groups in the diet of the eagle owl and the population of rodents in the environs of nesting areas. The importance of separate consideration of the main and other prey of the eagle owl in reconstruction of the composition of the fauna and structure of the rodent population based on subfossil ornithogenic materials is emphasized. [ABSTRACT FROM AUTHOR]

The paper presents data on the geochemical processes of postsedimentation transformations of boggy deposits at early diagenesis and the redistribution of chemical elements, including biogenic ones, in the Holocene sections of peat bogs in the Baraba forest-steppe in southern West Siberia. The contents of Fe, Mn, Pb, Hg, Sb, Cd, Cu, and Zn were found out to increase in the upper layers of the peat, whereas the S, N, Ca, and Sr concentrations increase in the middle parts of the peat profiles. The distribution character of various physiological groups of microorganisms in the peat profiles of Ubinskoe and Sherstobitovo peatlands lead to the conclusion that the nitrogen and carbon cycles are more active than that of sulfur. The activity of microorganisms leads to a decrease in pH and Eh in the vertical sections of the peatlands. The high values of , , TOC, and the chemical oxygen demand in the bog waters of Ubinskoe and Sherstobitovo bogs indicate that active biochemical decomposition and oxidation of organic matter proceed in these bogs. According to their predominant ions, the waters of the bogs belong to the hydrocarbonate class of the calcium group and are characterized by elevated concentrations of Al, Fe, Cu, and Zn, which is caused by the acid composition of the waters. The low pH values of the bog waters and the oxidizing environment facilitated the development of goethite–hydrogoethite mineralization in the upper horizon of peat profiles. The formation of hematite and anhydrite in the middle parts of the peat profiles was probably caused by paleofires. The authigenic minerals formed in the process of early diagenesis are, first of all, pyrite and less often siderite, calcite, and kaolinite. Under reducing conditions, nanoparticles of native Ni and Ni–Cr intermetallic compounds can be formed, and amorphous silica can be deposited at the dissolution of aluminosilicate minerals from the upper peat horizons. [ABSTRACT FROM AUTHOR]

We in this paper present a multi-proxy study of a 186-cm-long lacustrine sediment core (i.e., BY Core) obtained from the Youerdusi Basin in the middle Tianshan Mountains in an attempt to disentangle the causal associations among climate changes, ecological responses and hydrological variations. Palynological, assemblages and the associated biome scores indicate that the upper limit of the forest zone was closer to the Youerdusi Basin with a larger wetland extent in the Youerdusi Basin during the early part (i.e., from ~ 10.5 to ~ 5.8 cal. kyr BP) of the data-covering period (i.e., from ~ 10.5 to ~ 2.4 cal. kyr BP). The upper limit of the forest zone was farther away from the Youerdusi Basin with a smaller wetland extent in the Youerdusi Basin during the late part (i.e., from ~ 5.8 to ~ 2.4 cal. kyr BP). The changes of taiga biome score and the AP% ratio indicate a persistent cooling trend during the data-covering period which is well corroborated by various proxy data from nearby sites and the cooling trend is chronologically consistent with the trend of Northern Hemisphere temperature anomalies that was interpreted to be a delayed response to the summer solar irradiance at 50° N. The tundra biome score and the associated percentages of Cyperaceae in the Youerdusi Basin show two major stages of wetland extent variation. The wetland extent variation in the Youerdusi Basin might have been controlled by precipitation and/or by glacier-melting potential that was in turn controlled by both temperature and the extent of remained ice cover in higher elevations. The δ13Corg values obtained from the BY Core indicate a wetting trend during the data-covering period which is reasonably corroborated by various proxy data from nearby sites. We infer that the wetting trend was causally associated with the Holocene increasing trend of the North Atlantic Ocean SST (sea surface temperature) and also with the Holocene increasing trend of the westerlies' intensity. [ABSTRACT FROM AUTHOR]

In 2015, professional diver and amateur archaeologist A. Matiukas discovered an extraordinarily rich and well-preserved underwater multiperiod archaeological site, Kaltanėnai, at the point where the Žeimenys Lake feeds into the Žeimena River in East Lithuania. Over the duration of 3 years of multiple diving expeditions, he collected ca. 800 archaeological finds made of wood, bone, antler, flint, stone, iron and glass. Moreover, in eroded places of the river bed, he observed numerous wooden piles of potential constructions. These initial finds attested the newly discovered site’s great scientific value and potential, and therefore a scientific investigation of the site was initiated. This paper presents the first results of underwater survey at this site and analyses of its various finds. These include the site’s plan with a mapping of stationary fishing gear, a geological profile made from boreholes, 23 14C dates of various artefacts and wooden constructions, wood and animal taxa determinations including ZooMS, and traceological analysis of osseous tools. Our research demonstrates that the site was intensively used for fishing via various methods starting from the Late Mesolithic to the modern era, while most of the finds date to the Subneolithic and the Bronze Age. Further research at the site, including underwater excavations of stratified archaeological layers, will shed even more light onto the history of inland fishing in the East Baltic. [ABSTRACT FROM AUTHOR]

This paper focuses on southern Ethiopia, along the outer rim of the Rift Valley and not far from the Kenyan border, in an area forming part of a larger region known as a cradle of humankind. However, it also hosts a diverse Holocene rock art heritage, which is still underestimated and underdocumented. Paintings and engravings are widespread in the region, both in rock shelters and open-air sites, often located in remote areas currently inhabited by communities belonging to different ethnic groups. The aim of this paper is to present the first results of a new project in the area around Yabelo, within the broader framework of rock art research in East Africa, integrating archaeological research, preservation and heritage management with a relevant involvement of local communities. The outstanding cultural importance of these contexts offers new prospects for both scholarly research and sustainable development. The recording and study of the artworks is underway, using digital technologies that guarantee a high standard of accuracy of the documentation and non-invasive recording methods. This provides important insights for reconstructing cultural dynamics in the area between the final Pleistocene and onset of the Holocene. Moreover, the focus on rock art makes it possible to enhance local knowledge, increasing the awareness of local communities, with a significant impact on the preservation of this fragile heritage and the development of local, sustainable tourism projects. Differently from other archaeological features, rock art can have a more immediate attractiveness for contemporary observers, in terms of the apparent immediacy of the images and their emotional impact, raising awareness of cultural heritage and fostering major involvement in its preservation. [ABSTRACT FROM AUTHOR]

This paper reviews the, so far available, paleorecords of Vitis sylvestris C.C. Gmel and Vitis vinifera L. from Romania. The study takes into consideration the presence of Vitis pollen from Holocene peat sediment sequences and archaeological context, but also the presence of macrorests from various archaeological sites that date from Neolithic, Chalcolithic, Bronze Age, and La Tène. Both paleobotanical arguments and archaeological discoveries support the theory that places the beggining of viticulture in Romania a few millenia ago, in Neolithic period. Also, written evidences (works of classical authors, epigraphical sources) confirm, indirectly, the presence of grapevine in La Tène period. Occurrences of Vitis vinifera and those of Vitis sylvestris manifest independently of the climate oscillations, being present both through colder and more humid episodes, as well as through drier and warmer events. Probably prehistoric communities have made a constant and deliberate effort, all along the Holocene, to maintain grapevine crops. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study on peat deposits and radiocarbon dating of basal peat horizons in 43 peatlands located on three key sites within Meshchera Lowlands and Moksha Polesie. Peatlands formed by upland paludification processes and located on watersheds and terraces rising above floodplains were selected for the analysis. The obtained data indicate that the peatland formation process has been ongoing in these regions throughout the entire Holocene epoch and that this process has been affected by the fire regime in the area. In periods with higher wildfire frequencies (8800–5800 and 4200–3200 calendar years BP), changes in the water balance on flat and poorly drained plains occurring after the destruction of forest stands intensified the waterlogging processes. [ABSTRACT FROM AUTHOR]

The southern lowlands of Papua New Guinea (PNG) are biogeographically distinct. Vast tracts of savanna vegetation occur there and yet most palaeoecological studies have focused on highlands and/or forest environments. Greater focus on long-term lowland environments provides a rare opportunity to understand and promote the significance of local and regional savannas, ultimately allowing non-forested and forested ecosystem dynamics to be compared. This paper examines palaeoecological and archaeological data from a lowland open savanna site situated on the south-central PNG coastline. The methods used incorporate pollen and micro-charcoal analyses, artefact recovery and sediment descriptions. We conclude with an environmental model of sedimentation and vegetation change for the past c. 5,800 years, revealing a mid to late Holocene savanna interchange between herbaceous and woody plant growth, with fluctuating fire occurrence increasing toward the present day. Increased silt deposition and modified regional hydrology are also recorded. Environmental changes correspond in timing with the start of permanent settlements and human use of fire. In particular, landscape burning for hunting and gardens for agriculture have helped create the open ecosystem still evident today. [ABSTRACT FROM AUTHOR]

Abstarct: Jeju Island, which lies on the continental shelf in the southern Korean Peninsula, is the emergent portion of a basaltic volcanic field that has erupted since the Early Pleistocene (ca. 1.8 Ma). Volcanic activity that continued into historic times (ca. 1 ka) formed an elongated shield with a central edifice (Mt. Halla) and more than 300 monogenetic cones and rings. The establishment of a temporal framework for Jeju volcanism, particularly during the Late Pleistocene and Holocene activities, requires geochronological tools other than radiometric dating techniques, which are based on parent-daughter isotope pairs with geologically long half-lives, such as 40Ar/39Ar dating. In this study, we conducted quartz optically stimulated luminescence (OSL) dating of palaeosols intercalated with basaltic lava flows and scoria deposits, presumably ejected from three monogenetic volcanoes (Cheoreum, Darangsh and Dunjibong volcanoes) in the northeastern part of the island. Quartz extracts from the palaeosols had moderate to dim sensitivity to optical stimulation, but several prerequisite tests of the measurement protocols for equivalent dose estimation were successful. The coarse (63–250 μm) and fine (4–11 μm) quartz fractions yielded continuous wave (CW)-OSL ages of 19.9–7.0 and 18.6–6.7 ka, respectively, both of which were broadly consistent with the radiocarbon dates (10245–7440 Cal yr BP). These ages indicate that lava flows and scoria deposits covering the palaeosols are younger than ~7 ka. The pulsed OSL signals in coarse quartz extracts from the palaeosols suffered from poor counting statistics, thus it is recommended that they not be applied solely (i.e., without any other absolute ages to compare) to dating dim samples. From one of the sites investigated here, the averaged sedimentation rate of the palaeosol is estimated to be ~0.05 mm/yr, based on stratigraphically consistent CW-OSL ages. The OSL ages presented in this paper, together with previous OSL and radiocarbon ages, confirm that Jeju volcanic island was regionally active during the Holocene. [ABSTRACT FROM AUTHOR]

The study of dental morphology has proven useful for reconstructing the biological profiles of ancient populations. In this work, we present the results obtained by analysing dental non-metric traits in many of the most important Mesolithic burial contexts from the Iberian Peninsula. Currently, a substantial debate is underway regarding the relationship between the different geographical areas of the Peninsula and their different chronological moments. This paper is based on a sample consisting of a minimum number of 437 previously unpublished individuals from 11 Mesolithic and Neolithic sites, whose data were compared with Italian Mesolithic and Neolithic samples and posterior Iberian groups. We analysed these data by chi-squared analysis and by calculating the mean measure of divergence biological distance measure. There were no significant differences among the different regional groups from the Iberian Mesolithic. Moreover, the Iberian Mesolithic samples differ significantly from the Italian samples. In addition, although certain Neolithic samples differ from the hunter-gatherer profile, it seems that they received important biological influence from Mesolithic groups from the Iberian Peninsula, which varies with geography, since the farmer groups from the Mediterranean area are the most distinct from the previous hunter-gatherers. Our results suggest a common biological origin for all the Iberian Mesolithic assemblages, which probably originated during the Last Glacial Maximum. In addition, this profile differs from the one observed in Italian coetaneous groups. Finally, similar to the latest aDNA studies, this study suggests that the Neolithization process of the Peninsula was heterogeneous. [ABSTRACT FROM AUTHOR]

The Holocene hydrological regime on the Heixiazi Island is critical for understanding the evolution of the East Asian summer monsoon (EASM) for the island's climate-sensitive location on the northern fringe of the EASM domain. In this paper, a marsh depression on the central island was selected to reconstruct the locally hydrological variation and to discuss its indications for the Holocene EASM evolution. This work is based on multi-proxy (magnetic susceptibility, grain size, loss-on-ignition, and carbonate content) analyses of 22 modern sedimentary samples with a water-level gradient of 0–66 cm and 100 cored sedimentary samples covering last ~ 9.0 ka BP. The proxies' hydrological significance was previously interpreted by the 22 modern samples using linear regression equations to construct their relationships to water-level changes. Among these proxies, the magnetic susceptibility, carbonate content, as well as the Md and sand fraction of grain size exhibit high-level relationships against the water-level changes with R2 > 0.6. Thus, these four proxies' linear-regression equations were selected and used on the 100 cored samples, and the Holocene water-level changes in the studied depression were quantitatively reconstructed. It shows that two relatively high water-level stages with strengthened EASM occurred during 8.0–4.5 ka BP and 3.0–1.4 ka BP, which were alternated by three low water-level stages with declined EASM during ~ 9.0–8.0 ka BP, 4.5–3.0 ka BP, and 1.4–0 ka BP, respectively. Among these fluctuations, the highest water-level stage with most strengthened EASM which is defined as the Holocene Monsoon Maximum occurred during 6.4–4.5 ka BP. Such a new evolution pattern of the EASM can be further supported by a large variety of records from monsoon-margin regions. We suggest the Holocene EASM evolution was generally associated with the thermal conditions in both the inner Eurasia landmass and the West Pacific Ocean, with an exception of the weak EASM before 8.0 ka BP due to the enhanced Siberia High with the dominance of the Eurasia ice sheet in the early Holocene. [ABSTRACT FROM AUTHOR]

Rockfalls and rock avalanches are a recurrent process in high mountain areas like the Mont Blanc massif. These processes are surveyed due to the hazard they present for infrastructure and alpinists. While rockfalls and rock avalanches have been documented for the last 150 years, we know very little about their frequency since the Last Glacial Maximum (LGM). In order to improve our understanding, it is imperative to date them on a longer timescale. A pilot campaign using Terrestrial Cosmogenic Nuclide (TCN) dating of five samples was carried out in 2006 at the Aiguille du Midi (3842 m a.s.l.). In 2011, a larger scale study (20 samples) was carried out in five other test sites in the Mont Blanc massif. This paper presents the exposure ages of the 2011 TCN study as well as the updated exposure ages of the 2006 study using newer TCN dating parameters. Most of these exposure ages lie within the Holocene but three ages are Pleistocene (59.87 ± 6.10 ka for the oldest). A comparison of these ages with air temperature and glacier cover proxies explored the possible relationship between the most active rockfall periods and the warmest periods of the Holocene: two clusters of exposure ages have been detected, corresponding to the Middle Holocene (8.2-4.2 ka) and the Roman Warm Period (c. 2 ka) climate periods. Some recent rockfalls have also been dated (< 0.56 ka). [ABSTRACT FROM AUTHOR]

The Sabana de Bogotá in the northern Andes is an interesting region to investigate temporal patterns of dietary variation because it counts with a vast archeological and osteological record for the last 10,000 years. In this paper, stable isotope data of human archeological bone collagen and apatite were used to study the evolution of diet and major subsistence transformations taking place during the Holocene (∼9000-600 cal BP). Paleoenvironmental reconstructions and the isotopic ecology of the Sabana de Bogotá were used as an interpretative baseline. Stable isotope measurements (δ13Ccol, δ13Cap, δ15N, and Δ13Ccol-ap) representing hunter-gatherers, horticulturalists, and agriculturalists (N = 134 individuals) were analyzed by using bivariate, regressional, and discriminant statistical techniques. Results show that early Holocene hunter-gatherers (9000-7000 cal BP) consumed mostly C3 vegetal resources locally available. In contrast, animal protein was less important. Middle Holocene hunter-gatherers (6000-4500 cal BP) continued with the food foraging pattern observed in the earlier counterparts and presented a slight increase in C3 animal protein intake. During the initial late Holocene ca. 4000 cal BP, important shifts in subsistence strategies occurred when populations presented a trend toward mixed C3/C4 diets, and by ca. 3500 cal BP, there is a clear signal of C4 crops (i.e., maize) consumption concomitant with the introduction of ceramic technology. During the final late Holocene (last 2000 cal years BP), intensive agriculture was adopted and humans presented relatively diverse diets integrated by C4 and C3 crops, C3-C4 feeding animals, and freshwater resources. Such dietary change coincides with an increase in sociopolitical complexity, population size, and a general decline in health. [ABSTRACT FROM AUTHOR]

Quantification of vegetation cover from pollen analysis has been a goal of palynologists since the advent of the method in 1916 by the great Lennart von Post. Pollen-based research projects are becoming increasingly ambitious in scale, and the emergence of spatially extensive open-access datasets, advanced methods and computer power has facilitated sub-continental analysis of Holocene pollen data. This paper presents results of one such study, focussing on the Mediterranean basin. Pollen data from 105 fossil sequences have been extracted from the European Pollen database, harmonised by both taxonomy and chronologies, and subjected to a hierarchical agglomerative clustering method to synthesise the dataset into 16 main groupings. A particular focus of analysis was to describe the common transitions from one group to another to understand pathways of Holocene vegetation change in the Mediterranean. Two pollen-based indices of human impact (OJC: Oleaceae, Juglans, Castanea; API: anthropogenic pollen indicators) have been used to infer the degree of human modification of vegetation within each pollen grouping. Pollen-inferred cluster groups that are interpreted as representing more natural vegetation states show a restricted number of pathways of change. A set of cluster groups were identified that closely resemble anthropogenically-disturbed vegetation, and might be considered anthromes (anthopogenic biomes). These clusters show a very wide set of potential pathways, implying that all potential vegetation communities identified through this analysis have been altered in response to land exploitation and transformation by human societies in combination with other factors, such as climatic change. Future work to explain these ecosystem pathways will require developing complementary datasets from the social sciences and humanities (archaeology and historical sources), along with synthesis of the climatic records from the region. [ABSTRACT FROM AUTHOR]

Marine oxygen isotope stage 5a (MIS 5a), MIS 3a, and Holocene were highlighted periods in paleoclimate studies. Many scientists have published a great number of studies in this regard, but they paid more attention to qualitative research, and there was often a lack of quantitative data. In this paper, based on chronological evidence from a paleolake in arid China, MIS 5a, MIS 3a, and Holocene lake area, the precipitation of the drainage area and the runoff of the inflowing rivers of the lake were reconstructed with ArcGIS spatial analysis software and the improved water and energy balance model which was calibrated by modern meteorological and hydrological data in the Shiyang River drainage basin. The results showed that the paleolake areas were 1824, 1124, and 628 km for MIS 5a, MIS 3a, and Holocene; meanwhile, the paleoprecipitation and runoff were 293.992-297.433, 271.105-274.294, and 249.431-252.373 mm and 29.103 × 10-29.496 × 10, 18.810 × 10-18.959 × 10, and 10.637 × 10-10.777 × 10 mm, respectively. The quantitative data can help us not only strengthen the understanding of paleoclimatic characteristics but also recognize the complexity and diversity of the climate system. [ABSTRACT FROM AUTHOR]

Holocene sequences of the Russian Arctic shelf seas are controlled by a combination of three main factors: deglaciation of the Late Pleistocene Barents-Kara ice sheet, global sea-level rise, and river runoff from Eurasia. Sedimentation in the Kara Sea is mainly defined by two latter factors. The lithological, grainsize, mineralogical, and micropaleontological compositions of the Holocene sequences of this basin have been widely studied, but only a few works report geochemical data. This paper considers comprehensive geochemical data on two cores from the Yenisei transect obtained during cruise of the R/V Akademik Petrov in 2000. Both the cores were dated by radiocarbon accelerator mass spectrometric method (AMS C) and analyzed using XRF and ICP MS methods. The study revealed and described differences in their chemical composition, which are caused by different facies settings of accumulation, their grain size composition, and influence of river run-off. [ABSTRACT FROM AUTHOR]

This paper considers regularities governing the formation of automorphic tundra soils on glacial loamy deposits containing relict organic matter mainly represented by very fine plant detritus. Drainage, microtopography, and cryoturbation activity are the major controls of the development of these soils. With an increase in drainage, the following pedogenetic trend is observed on the surface of yedoma (Ice Сomplex) areas: gleyzem-cryozem-cryometamorphic soil. The climate change in the Holocene induced quick transformation of topography and general landscape situation and promoted formation and development of cryogenic soil complexes in the considered territory. Upon the low intensity of pedogenesis, the features and properties of previous soil formation stages are often preserved in the soil profiles; these are: gleyzation, peat accumulation, and cryoturbation. [ABSTRACT FROM AUTHOR]

The evolution of the East Asian summer monsoon (EASM) during the Holocene has long been of significant interest. Knowledge of past EASM variability not only increases our understanding of monsoon dynamics on a long timescale, but it also provides an environmental and climatic background for research into Chinese cultural development. However, the timing of the EASM maximum remains controversial. The popular concept of an 'early Holocene maximum' is mainly based on speleothem δO ( δ O) records from caves in southern China; however, the interpretation of δ O as a reliable proxy for EASM intensity is being increasingly challenged. The present paper is a critical review of the climatic significance of the δ O record from China. Firstly, we suggest that precipitation in northern China is an appropriate index of EASM intensity, the variation of which clearly indicates a mid-Holocene monsoon maximum. Secondly, an interregional comparison demonstrates that the precipitation record in northern China is quite different from that in southern China on a range of timescales, and is inconsistent with the spatial similarity exhibited by speleothem oxygen isotope records. Furthermore, both modeling and observational data show that the δ Oc records from southern China indeed reflect changes in precipitation δ O ( δ O) rather than precipitation amount, and therefore that their use as an EASM proxy is inappropriate. Finally, we address several significant monsoon-related issues-including the driving mechanism of the EASM on an orbital timescale, the climatic significance of speleothem oxygen isotopes, and the relationship between atmospheric circulation and precipitation in monsoonal regions. [ABSTRACT FROM AUTHOR]

Shell mounds, or middens, are artificial accumulations of food remains such as shells, sediments, artefacts and remains from daily life and funerary rituals, which were deposited in our study area by groups of Sambaquian fisher-hunter-gatherers. These mounds contain remains, which are representative of the fauna and flora at the time they were formed, enabling the recovery of palaeoenvironmental data related to biodiversity of taxa and biogeography, 14C dating and analysis of changes in the patterns of marine biodiversity and ocean circulation. This paper uses the Casa de Pedra shell mound rock shelter, located in São Francisco do Sul, state of Santa Catarina, southeastern Brazil, to study aspects of the palaeoenvironment through analyses of the archaeological material of the site, which contains well-preserved phytoliths and sponge spicules. Among the phytoliths, those from grasses predominate and some trees and palms were present, with no variation in vegetation type during the period of site occupation, between 5,470 and 4,460 years bp. Despite the general stability of the vegetation, a small increase in the density of the tree cover was identified from the base to the top, which may be related to an increase in precipitation, and is in agreement with other palaeoenvironmental studies carried out in southern Brazil. [ABSTRACT FROM AUTHOR]

In this paper we test the performance of the Regional Estimates of VEgetation Abundance from Large Sites (REVEALS) model using pollen records from multiple small sites. We use Holocene pollen records from large and small sites in southern Sweden to identify what is/are the most significant variable(s) affecting the REVEALS-based reconstructions, i.e. type of site (lakes and/or bogs), number of sites, site size, site location in relation to vegetation zones, and/or distance between small sites and large sites. To achieve this objective we grouped the small sites according to (i) the two major modern vegetation zones of the study region, and (ii) the distance between the small sites and large lakes, i.e. small sites within 50, 100, 150, or 200 km of the large lakes. The REVEALS-based reconstructions were performed using 24 pollen taxa. Redundancy analysis was performed on the results from all REVEALS-model runs using the groups within (i) and (ii) separately, and on the results from all runs using the groups within (ii) together. The explanatory power and significance of the variables were identified using forward selection and Monte Carlo permutation tests. The results show that (a) although the REVEALS model was designed for pollen data from large lakes, it also performs well with pollen data from multiple small sites in reconstructing the percentage cover of groups of plant taxa (e.g. open land taxa, summer-green trees, evergreen trees) or individual plant taxa; however, in the case of this study area, the reconstruction of the percentage cover of Calluna vulgaris, Cyperaceae, and Betula may be problematic when using small bogs; (b) standard errors of multiple small-site REVEALS estimates will generally be larger than those obtained using pollen records from large lakes, and they will decrease with increasing size of pollen counts and increasing number of small sites; (c) small lakes are better to use than small bogs if the total number of small sites is low; and (d) the size of small sites and the distance between them do not play a major role, but the distance between the small sites and landscape/vegetation boundaries is a determinant factor for the accuracy of the vegetation reconstructions. [ABSTRACT FROM AUTHOR]

This paper presents the results of wood charcoal analysis carried out on material from Theopetra cave in central Greece. The sequence dates from prior to 130-8 ka bp and is made up of layers of both anthropogenic and geogenic origins. The study of the wood charcoal samples from these layers sets out to distinguish changes in the local vegetation through time, to correlate these with broader environmental conditions and to discuss how they may relate to differences in the frequency and intensity of human occupation of the cave from shortly before the last interglacial to the Holocene. Changes in the presence and frequency of Prunus sp., Juniperus sp. as well as taxa needing temperate, thermophilous or riverine conditions in successive layers reflect a pattern of vegetation succession that can be correlated with the pollen and marine isotope stage (MIS) records. The earliest human occupation took place in an open park-woodland environment dominated by Prunus during the late MIS 6-6/5 transition. This was followed by a succession of temperate woodlands with deciduous Quercus, Carpinus and Fraxinus, reflecting the optimal conditions of the last interglacial (MIS 5e), followed by more open vegetation during subsequent cooling events. Middle Palaeolithic hunter-gatherers visited the cave repeatedly during the last interglacial, in contrast to more sporadic human presence during the following climatic deterioration. This was characterized by Juniperus dominated steppe and open vegetation and/or riparian woods, reflecting the harsh and unstable climatic conditions of the pleniglacial. Finally, the expansion of Pistacia and re-establishment of temperate woodland points to climatic amelioration during the Holocene from which there is evidence of regular use of the cave by Mesolithic and Neolithic people. The dominant role of Prunus observed in several periods provides important complementary information to the pollen evidence from the late Pleistocene. [ABSTRACT FROM AUTHOR]

Deserts and sandylands that are located in the semi-arid and arid regions in the middle latitudes of the Northern Hemisphere are usually regarded as environmentally sensitive change belts which respond to global climatic change. In northern China, activation or immobilization of sand dunes is mainly influenced by humid and dry variation and is related to stronger or weaker Asian monsoons. In this paper, the history of Holocene millennial-scale climatic and environmental change is reconstructed by the systematic analysis of the geochemical element contents and parameters, along with the OSL and C chronologies, from the different lithologies of the palaeosol-aeolian sand sequence in the south-eastern Mu Us Desert, northern China. Our results indicate that the region was dominated by a dry climate with intensive aeolian activity before 7.2 ka BP, and there was an optimal humid climate and fixed desert in 7.2-4.6 ka. Afterwards, the dune fields became mobile again as the effective humidity declined. Additionally, six dry events were discovered with times of ~7.2, 7.0-6.8, 6.6-5.7, 4.6-4.1, 3.7-3.5, and 3.3-2.5 ka, which were not only coincident with the intervals of millennial-scale weaker Asian summer monsoons, but also accordant with the cold events evidenced in the ice cores and deep-sea deposits of the high latitudes in the Northern Hemisphere. In general, the Holocene climatic and environmental changes had the characteristics of the 'monsoonal mode' and 'abrupt millennial-scale oscillation' in the Mu Us Desert. [ABSTRACT FROM AUTHOR]

The East Asian winter monsoon (EAWM) exhibits significant variability on intraseasonal, interannual, and interdecadal time scales and the variability can be extended to Holocene centennial and millennial scales. Previous Holocene EAWM proxy data records, which were mostly located in Central, Eastern and Southern China, did not show a consistent Holocene EAWM history. Therefore, it is difficult to provide insights into mechanisms of the long-term winter monsoon variability on the basis of the records. Eolian sediments at the southern edge of the Gobi Desert, Western China, are sensitive to the EAWM changes and less affected by the East Asian summer monsoon due to an obstruction of the Qinghai-Tibet Plateau. This paper presents a comparison between a well-dated Holocene EAWM record and coupled climate model simulations, so as to explore physical processes and influencing factors of the Holocene EAWM. Sediment samples from two Holocene eolian sedimentary sections [Huangyanghe (a) and Huangyanghe (b)] were acquired at the southern edge of the Gobi Desert. Chronologies were established based on twenty bulk organic matter AMS C ages and five pollen concentrates AMS C ages. Proxy data, including grain-size, total organic carbon, magnetic susceptibility and carbonate content were obtained from the two eolian sections. The grain-size standard deviation model was applied to determine components sensitive to variability of the Holocene EAWM. After a comparison of environmentally-sensitive grain-size components and proxy data, the 20-200 μm component at the Huangyanghe (a) and the 20-159 μm component at the Huangyanghe (b) section were selected as indicators of the Holocene EAWM, which show a strong early Holocene winter monsoon and a decline of the winter monsoon since the mid-Holocene. We also present equilibrium and transient simulations of the climate evolution for the Holocene using a state-of-art coupled climate model: the Community Climate System Model version 3 (CCSM3). Indices for the Holocene EAWM were calculated and are consistent with the reconstructed Holocene EAWM intensity. The simulations indicate that orbital forcing effects on the land-sea temperature and sea level pressure contrast can account for the observed EAWM trends. Other forcings that were present in the early Holocene, including the remnant Laurentide ice sheet and meltwater forcing in the North Atlantic, were not responsible for the Holocene trends. [ABSTRACT FROM AUTHOR]

In this paper, we discuss human occupation during the Early and Middle Holocene in the Eastern Desert of Egypt, based mainly on the data provided by excavated deposits from the Sodmein Cave, which produced an important Holocene stratigraphic sequence. This sequence is dated by a large number of conventional and AMS C dates. It appears that the area was empty of human occupation during the Late Glacial Maximum (LGM) and the earliest Holocene. With improved climatic conditions, humans arrived in the area, as hunter-gatherers using no ceramics, from around 7.1 to 6.4 Ka cal BC. Humans were absent from the cave during the Holocene 8.2 Ka event ( ca. 6.3 Ka cal BC). From 6.2 to 5.0 Ka cal BC, herders visited the site on a regular basis importing caprines. The bone evidence for domesticated small stock is very limited at Sodmein but is nevertheless extremely important, as it contains the oldest known specimens for Africa to date. After 5.0 Ka cal BC, the area was almost entirely deserted. [ABSTRACT FROM AUTHOR]

This paper documents a 7800-year proxy record from the Shenjiadian peatland on the Sanjiang Plain in Northeast China. High-resolution plant macrofossil and colorimetric humification methods were used to reconstruct the vegetation and hydrologic history from a 193 cm-long sedimentary profile. Detrended correspondence analysis (DCA) was applied to transform the raw plant macrofossil data into latent indices of peatland water level. The vegetation community transited from an Equisetum fluviatile community to a Carex lasiocarpa community at approximately 3800 cal yr BP and was followed by a Carex-shrub community at approximately 480 cal yr BP. Based on the plant macrofossil DCA axis 1 scores and humification values, we distinguished four hydrologic periods: a wet period from 7800 cal yr BP to 4500 cal yr BP, dry periods up to 1600 cal yr BP, drier periods until 300 cal yr BP, and the driest period from 300 cal yr BP until the present. Through a comparison with other climate records, we suggest that the East Asian summer monsoon (EAM) was the main driving force for vegetation and water level changes to the Shenjiadian peatland through its impacts on precipitation. [ABSTRACT FROM AUTHOR]

Throughout the Holocene, Lake Turkana has been subject to drastic changes in lake levels and the subsistence strategies people employ to survive in this hot and arid region. In this paper, we reconstruct the position of the lake during the Holocene within a paleoclimatic context. Atmospheric forcing mechanisms are discussed in order to contextualize the broader landscape changes occurring in eastern Africa over the last 12,000 years. The Holocene is divided into five primary phases according to changes in the strand-plain evolution, paleoclimate, and human subsistence strategies practiced within the basin. Early Holocene fishing settlements occurred adjacent to high and relatively stable lake levels. A period of high-magnitude oscillations in lake levels ensued after 9,000 years BP and human settlements appear to have been located close to the margins of the lake. Aridification and a final regression in lake levels ensued after 5,000 years BP and human communities were generalized pastoralists-fishers-foragers. During the Late Holocene, lake levels may have dropped below their present position and subsistence strategies appear to have been flexible and occasionally specialized on animal pastoralism. Modern missionary and government outposts have encouraged the construction of permanent settlements in the region, which are heavily dependent on outside resources for their survival. Changes in the physical and cultural environments of the Lake Turkana region have been closely correlated, and understanding the relationship between the two variables remains a vital component of archaeological research. [ABSTRACT FROM AUTHOR]