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This paper reviews the reconstruction of European Atlantic storm events with the contribution of a new stormy reconstruction in its central part. Three marsh environments on the island of Yeu were chosen to identify disturbing storm events from the Mid- to Late Holocene with vibracore sampling, radiocarbon dating and sedimentary analysis. Nine probable intervals of high energy deposition in these low-transport-activity environments are estimated: 600–500, near 1590, 2100–1950, 2850–2350, 3500–3270, 5400–5370, 6650–6510, near 7000 and between 7670 and 7470 calibrated years before present (cal y BP). By comparison with sedimentological paleostorm studies, we confirm six European Atlantic storm events estimated at near 600–300, 1700–1100, 2900–2500, 3500–3300, 5500–5100 and 7700–7100 cal y BP, corresponding to worldwide Holocene cooling climatic periods. A comparison with other storminess reviews of worldwide main stormy coasts shows that Holocene storms can increase during global cooling periods in the northern hemisphere. [ABSTRACT FROM AUTHOR]

The present phylogeographic pattern of red deer in Eurasia is not only a result of the contraction of their distribution range into glacial refugia and postglacial expansion, but probably also an effect of replacement of some red deer s.l. mtDNA lineages by others during the last 50 000 years. To better recognize this process, we analysed 501 sequences of mtDNA cytochrome b , including 194 ancient and 75 contemporary samples newly obtained for this study. The inclusion of 161 radiocarbon-dated samples enabled us to study the phylogeny in a temporal context and conduct divergence-time estimation and molecular dating. Depending on methodology, our estimate of divergence between Cervus elaphus and Cervus canadensis varied considerably (370 000 or 1.37 million years BP, respectively). The divergence times of genetic lineages and haplogroups corresponded to large environmental changes associated with stadials and interstadials of the Late Pleistocene. Due to the climatic oscillations, the distribution of C. elaphus and C. canadensis fluctuated in north–south and east–west directions. Some haplotypes dated to pre-Last Glacial Maximum periods were not detected afterwards, representing possibly extinct populations. We indicated with a high probability the presence of red deer sensu lato in south-eastern Europe and western Asia during the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

The paper reports the results of a palynological study of a newly exposed section in the peat sediments of Bezděkov site and its correlation with the previous palaeobotanical studies. The main goal was to elucidate the stratigraphic position and paleogeographic development of fossil peat bog and its environment in the Protected Landscape Area Žďárské vrchy and Železné hory in the Bohemian-Moravian Uplands. The development of peatbog vegetation, as shown by the pollen analysis and radiocarbon dating, took place in the Holocene. Pollen analyses provide evidence for occurrences of wetland assemblages with huge representation of alder wood in all the part of succession, followed by willow near the Cerhovka Brook. Alnus and Abies were the dominant trees during all the time. The deciduous forests consist of elm ( Ulmus), oak ( Quercus), lime tree ( Tilia), maple ( Acer) and hazel ( Corylus). The mosaic picture of woodland and wetland, which covered this landscape during the Upper Holocene, contrasts with the present day monotonous open lowland. Sediments of the peat bog provide information on the origin and vegetation evolution of this area. [ABSTRACT FROM AUTHOR]

Aim: The Expansion‐Contraction model has been used to explain the responses of species to climatic changes. During periods of unfavourable climatic conditions, species retreat to refugia from where they may later expand. This paper focuses on the palaeoecology of red deer over the past 54 ka across Europe and the Urals, to reveal patterns of change in their range and explore the role of environmental conditions in determining their distribution. Location: Europe and western Asia to 63°E. Taxon: Red deer (Cervus elaphus). Methods: We collected 984 records of radiocarbon‐dated red deer subfossils from the Late Pleistocene and the Holocene, including 93 original dates. For each deer sample we compiled climatic and biome type data for the corresponding time intervals. Results: During the last 54 ka changes in red deer range in Europe and the Urals were asynchronous and differed between western and eastern Europe and western Asia due to different environmental conditions in those regions. The range of suitable areas for deer during the Last Glacial Maximum (LGM) was larger than previously thought and covered vast regions not only in southern but also in western and eastern Europe. Throughout the period investigated the majority of specimens inhabited forests in the temperate climatic zone. The contribution of forests in deer localities significantly decreased during the last 4 ka, due to deforestation of Europe caused by humans. Mean January temperature was the main limiting factor for species distribution. Over 90% of the samples were found in areas where mean January temperature was above −10°C. Main conclusions: Red deer response to climatic oscillations are in agreement with the Expansion‐Contraction model but in contradiction to the statement of only the southernmost LGM refugia of the species. During the last 54 ka red deer occurred mostly in forests of the temperate climatic zone. [ABSTRACT FROM AUTHOR]

Spring-fed fen deposits (peat-tufa sequences) from northern Poland were investigated for Holocene environmental reconstruction (climate and hydrology) using multi-proxy analysis (lithofacies, molluscs, pollen, plant macrofossils, geochemistry, and stable oxygen- and carbon-isotopes). The main aims of these studies were: (1) comparison of several similar sites with the same type of groundwater supply and sedimentation on a widespread space scale, (2) detailed reconstruction of their long-term development, assessing their sensitivity to climate change, (3) verification of the synchronicity of the record of different proxies in distant sites in the context of Holocene climate changes in relation to specific well-known global and/or regional climate events (so-called Bond events), and (4) discussion on permafrost degradation as a driver of spring-fed fens development. Based on our palaeogeographical data, we have distinguished an asynchronicity of the beginning of the development of spring-fed fens in the eastern and western parts of the studied region that is associated with different times of ascending groundwater supply unblocking after complete permafrost degradation. Therein, asynchronicity of permafrost degradation was brought about by multiple climatic, geological and structural conditions. Our results also indicate significant differences in the trends of succession (ecological and lithological) caused by the geographical location of the studied sites. Asynchronicity of the occurrence of wet and dry phases, as well as significant differences in their duration were noted. This depended upon the influence of oceanic (western part) or continental climates (eastern part). Warm and humid oceanic climate promoted the domination and longer duration of wet phases (especially in the Eo- and early Mesoholocene), while the harsh continental climate promoted the more frequent occurrence of dry phases, with short episodes of increased humidity. From the middle Mesoholocene, this marked regional diversification becomes less pronounced. Results also allowed for the recognition of several palaeoclimatic events on a regional scale. Four main cold episodes (Bond events 8–5): during LG/H transition (11.5 ky cal BP), Eo- (∼10.25 ky cal BP, ∼9.4 ky cal BP) and at the beginning of the Mesoholocene (∼8.2 ky cal BP) are well-documented by multiple proxies at all study sites. Other cold episodes (Bond events 4–0) are slightly less documented and are not clear for interpretation. The results of our study demonstrate the importance of spring-fed fen deposits for detailed palaeoenvironmental reconstruction on a regional scale. • Start of spring-fed fens development was different in time and space. • Unblocking of the ascending groundwater supply after permafrost degradation was essential. • Asynchronicity of wet and dry phases depends on climate – either oceanic or continental. • Significant differences in duration of phases are noticeable. • Warm and humid climate promote longer duration of wet phases in the Eo- and early Mesoholocene. [ABSTRACT FROM AUTHOR]

The forest-steppe ecotone in southern Siberia is highly sensitive to climate change; global warming is expected to push the ecotone northwards, at the same time resulting in degradation of the underlying permafrost. To gain a deeper understanding of long-term forest-steppe carbon dynamics, we use a highly resolved, multiproxy, palaeolimnological approach, based on sediment records from Lake Baikal. We reconstruct proxies that are relevant to understanding carbon dynamics including carbon mass accumulation rates ( CMAR; g C m−2 yr−1) and isotope composition of organic matter ( δ13 CTOC). Forest-steppe dynamics were reconstructed using pollen, and diatom records provided measures of primary production from near- and off-shore communities. We used a generalized additive model ( GAM) to identify significant change points in temporal series, and by applying generalized linear least-squares regression modelling to components of the multiproxy data, we address (1) What factors influence carbon dynamics during early Holocene warming and late Holocene cooling? (2) How did carbon dynamics respond to abrupt sub-Milankovitch scale events? and (3) What is the Holocene carbon storage budget for Lake Baikal. CMAR values range between 2.8 and 12.5 g C m−2 yr−1. Peak burial rates (and greatest variability) occurred during the early Holocene, associated with melting permafrost and retreating glaciers, while lowest burial rates occurred during the neoglacial. Significant shifts in carbon dynamics at 10.3, 4.1 and 2.8 kyr bp provide compelling evidence for the sensitivity of the region to sub-Milankovitch drivers of climate change. We estimate that 1.03 Pg C was buried in Lake Baikal sediments during the Holocene, almost one-quarter of which was buried during the early Holocene alone. Combined, our results highlight the importance of understanding the close linkages between carbon cycling and hydrological processes, not just temperatures, in southern Siberian environments. [ABSTRACT FROM AUTHOR]

The paper presents the results of interdisciplinary (multiproxy) palaeoenvironmental studies of peat - calcareous tufa depositional sequences of spring mire from Radzików site (east Poland). Analyses of three biotic proxies (plant macrofossils, pollen, molluscs) were supplemented with sedimentological, geochemical, oxygen and carbon stable isotopes analyses and radiocarbon dating and used for reconstruction of environmental changes in Late Glacial and Holocene. The obtained results enable us to (1) reconstruct main phases of mire development and (2) determine environmental factors influencing changes of water supply. The object started to develop in Allerød. The Late Glacial and Early Holocene deposit sequence is relatively thick (about 1.0 m), with good palaeoecological record. The boundary between Younger Dryas and Preboreal is especially well confirmed by palynological and malacological analyses as well as radiocarbon dating. The Mesoholocene deposits are considerably worse preserved. Mire development was evaluated in terms of general mire ecology. [ABSTRACT FROM AUTHOR]

14C concentration measurements together with carbon and oxygen stable isotope analysis in calcareous tufa give possibilities for reconstruction of time scale and palaeoclimatic conditions of sedimentary processes. Results of isotope examinations of 2 profiles with organic and tufa sediments from Eastern Poland and 8 calcareous tufa sites from Eastern India (Orissa) are given. A systematic error of 14C conventional age of carbonate fraction of tufa samples as reservoir age (TR) was estimated. The TR values of different type of tufa sediment are determined by stream water energy. On the basis of known experimental dependence between TR and δ13C for tufas deposited in high, average and low energy water, unknown values of TR and corrected 14C ages (TCCA) were calculated for samples from India tufa sites. Continuous deposition of organic and carbonate sediments in Polish profiles give the possibility to calculate the approximated TCCA ages on the basis of dependence between TCCA and a sample depth in a profile, and time scale reconstruction of δ13C and δ18O changes in carbonate fraction of tufa samples during the whole Holocene. [ABSTRACT FROM AUTHOR]

Measurements of δ18O and δ13C in tufa samples dated by 14C method have been used to reconstruct climatic changes in Southern and Eastern Poland and in Eastern India (Orissa) for the last ca 13,500 years. Stable isotope time record δ18O in calcareous tufa profiles can be interpreted as palaeoclimatic record if dependence between oxygen isotope composition and temperature for the specific climatic region is known. Estimated sedimentation temperatures of calcareous tufas from Polish sites indicate the mean year of air temperatures during the last 12,000 years and mean winter and summer temperature for Orissa state, using stable isotope analysis for calcareous tufa from Indian sites. The estimated temperatures have real values, comparable with contemporaneous sedimentation temperature. The characteristic trend of the temperature changes increasing for Poland and decreasing for Orissa, since the beginning of the Holocene till today, can be observed with climatic optimum ca 5 000- 6000 BP synchronous in both countries. [ABSTRACT FROM AUTHOR]

Palaeoecological analyses of Falkland Island peat profiles have largely been confined to pollen analyses. In order to improve understanding of long-term Falkland Island peat development processes, the plant macrofossil and stable isotope stratigraphy of an 11,550 year Falkland Island Cortaderia pilosa ('whitegrass') peat profile was investigated. The peatland developed into an acid, whitegrass peatland via a poor fen stage. Macrofossil charcoal indicate that local fires have frequently occurred throughout the development of the peatland. Raman spectroscopy analyses indicate changes in the intensity of burning which are likely to be related to changes in fuel types, abundance of fine fuels due to reduced evapotranspiration/higher rainfall (under weaker Southern Westerly Winds), peat moisture and human disturbance. Stable isotope and thermogravimetric analyses were used to identify a period of enhanced decomposition of the peat matrices dating from ∼7020 cal yr BP, which possibly reflects increasing strength of the Southern Westerly winds. The application of Raman spectroscopy and thermogravimetric analyses to the Falkland Island peat profile identified changes in fire intensity and decomposition which were not detectable using the techniques of macrofossil charcoal and plant macrofossil analyses. • An 11,550 year Falkland Island peat profile records a constant presence of burning. • Raman spectroscopy identifies changes in burning intensity. • TGA analyses indicate changes in the preservation of the peat matrices. • Increased strength of the Southern Westerly winds identified at ∼7020 cal. BP. [ABSTRACT FROM AUTHOR]