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This paper discusses the results of siliceous microfossils studies performed in a “staircase” of four isolation basins (33.7 m–2.9 m a.s.l.) on Big Solovetskiy Island (Solovki Archipelago, the White Sea). Diatoms were used as a primary group for paleoinferences, while chrysophyte cysts and sponge spicules also demonstrated high indicative potential. In all study lakes, the siliceous microfossils stratigraphy revealed three main stages of their evolution, i.e. large-basin, transitional and small-lake stages, each characterized by certain composition of the diatom assemblages and floristic diversity, relative abundances of chrysophyte cysts and sponge spicules, and siliceous microfossils concentrations. In the uppermost lake, glaciolacustrine environments unfavorable for aquatic biota existed during the large-basin stage. The proglacial lake stage terminated prior to ca. 10.4 cal ka BP, followed by a (semi)terrestrial episode before the transition to small-lake environments. In the other three lakes, marine environments were inferred at the earlier stage, characterized by the predominance of marine and brackish-marine diatoms, increased proportions of sponge spicules and low “cysts to diatoms” ratio. At the transitional marine-freshwater stage, mass growth of small fragilarioid diatoms and decreased abundances of spicules indicated unstable environments, while increased proportions of cysts pointed to progressive freshening of the basins. The duration of the marine-freshwater transition expectedly prolonged from ca. 200 yr in the upper basin (16.6 m a.s.l) to ca. 500 yr in the lowermost lake (2.9 m a.s.l.). The isolation from the sea took place between ca. 6.3 and 1.4 cal ka BP. At the small-lake stage, siliceous microfossils stratigraphies reflected local specifics of the basins and their catchments. We argue that besides traditionally used diatom data, relative and absolute abundances of siliceous microfossils also possess high indicative value for isolation basin studies. Our study demonstrated that marine waters on Big Solovetskiy Island never reached ca. 34 m a.s.l. during the Holocene, unlike the western coast of the Onega Bay where the Preboreal marine intrusion was recorded even at higher elevated localities. Different rates and amplitudes of shoreline displacement are thus suggested for the inner and outer parts of the Onega Bay. During the mid-Holocene Tapes transgression, before ca. 6.3 cal ka BP, the relative sea level on Big Solovetskiy Island exceeded 17 m a.s.l. The average estimated rates of the shoreline retreat during the second half of the Holocene gradually decreased from 0.28 cm year−1 to 0.2 cm year−1, indicating slowed isostatic uplift.

In the granitic part of the eastern Massif Central (France), the Gourd des Ailleres (GDA) mire provides one of the only Late-Glacial and Early Holocene sequences with a continuous sedimentation since the Oldest Dryas around 16000 years calibrated Before Present (16 ka cal. BP). Bioclimatic and hydrological changes were reconstructed based on sedimentological parameters, as well as by means of plant and animal macrofossils, pollen, and diatoms analyses through time. The environmental history of this site started with a small lake formed behind a moraine-dam. The multi-proxy study of the sedimentary sequence demonstrated that the coldest conditions took place around 14.3 ka cal. BP, at the very end of the Oldest Dryas. The Bolling period (14.2–13.9 ka cal. BP) was obviously warmer than the Allerod period (13.9–12.8 ka cal. BP) in the Monts du Forez Mountains. However, both chronozones presented a short cooling phase: the Intra Bolling Cold Period (IBCP) and the Intra Allerod Cold Period (IACP), respectively. The Older Dryas (14–13.9 ka cal. BP) was identified for the first time in this region based on pollen and diatom indicators. Thereafter, the Younger Dryas (12.9–11.7 ka cal. BP) was characterised by major temperature fluctuations. Windy conditions prevailed as indirectly demonstrated by the high frequency of Aulacoseira diatoms in the sequence. The onset of the Holocene was dated to 11.7 ka cal. BP. Peat-forming processes started thereafter due to the quick postglacial warming and the former GDA lake finally evolved into a limnogenous mire at the end of the Preboreal (10.4 ka cal. BP).

The Holocene has always been considered a crucial epoch where the major cultural steps of humankind took place. Understanding past Holocene climatic variability, shifts in vegetation, and faunal communities are among crucial challenges in predicting the upcoming changes of the natural environment. In Central Europe, the Krakow-Czestochowa Upland is one of the best study areas for detecting faunal, environmental, and climate shifts. For that reason, we choose to study the small vertebrate and mollusc communities of three archaeological sites with Holocene horizons: Sąspowska Zachodnia Cave, Ciasna Cave, and Male Rockshelter. We analysed the faunal community shifts, and we compared our results with the major Holocene sites in the area with the correspondence and cluster analyses. The environment and climate were reconstructed through Habitat Weighting, Quantified Ecology, malacological spectra and Bioclimatic methods. Environment and climate values showed a temporary replacement of the Late Glacial tundra and grasslands with boreal forest mixed with open wetlands during the Preboreal and then stable landscapes dominated by temperate forests. Models based on rodent data show that temperature and precipitation generally increased, starting from the Boreal, to reach values near, or sometimes overwhelm, the current climate values of the area during the Atlantic and Subboreal. The climate values obtained from herpetofaunal analyses show very slight changes between the Preboreal and the Atlantic (Ciasna Cave layers 3 and 4), except for the winter temperatures, whereas results obtained for Sąspowska Zachodnia Cave are probably biased by a very low number of recovered remains. Among rodents, a major negative oscillation detected in layers related to the edge of Early Holocene was related to the Preboreal Oscillation or long-lasting effect of the Younger Dryas.

Lateglacial and Holocene sandy aeolian sequences with palaeosol horizons located in different sedimentary zones in western-central Poland were analysed in order to establish their regional stratigraphical and palaeoenvironmental significance. Results of sedimentological, geomorphological and absolute dating methods from 3 representative profiles from an extraglacial zone (Leszczyca site), a glaciomarginal zone (Barczyglow site) and a glaciated zone (Godzieba site) are presented. A compilation of 31 luminescence dates from aeolian sands and 7 14C-dates from palaeosols formed the basement for establishing the stratigraphic position of the analysed deposits. The obtained results were correlated with reference to Greenland ice-core chronology, which has the best resolution for the Northern Hemisphere. In the extraglacial zone, aeolian deposition started in the Oldest Dryas and continued throughout the Older Dryas (main phase of dune built) with limited deposition in the Younger Dryas and finished in Preboreal. Aeolian deposition was interrupted by pedogenic processes in the Bolling and Allerod interstadials as well as in the Younger Dryas-Preboreal transition. Whereas in the glaciomarginal zone aeolian deposition started in the Younger Dryas and continued to the Early Boreal with a weakly expressed pedogenic process in the Early Preboreal. In the glaciated zone, aeolian deposition took place in the Younger Dryas. At the Barczyglow and Godzieba sites palaeosols of the Roman Period and 19th century were detected, covered by aeolian sands. The Subatlantic aeolian episodes were induced by human activity and registered forest fires. Identified periods of aeolian activity and pedogenic processes were correlated with other profiles from central and western Europe.

In the northern part of the Polish Outer Western Carpathians, the Beskid Makowski Mts., four landslides formed during the Late Glacial have been identified, so far. Within the depositional sequences (organic-mineral) of fens occurring in landslide depressions, palaeoenvironmental changes of the Late Glacial and the Holocene are recorded. The oldest of fen, started to form in the Oldest Dryas Stadial, the younger ones – in the Bolling Interstadial (two fens) and in the Older Dryas Stadial. The thickness of fen deposits varies from 1.5 m to 4.5 m. The sediments deposited in the Late Glacial represent long sequences (reaching 50–80% of the profile), whereas the Holocene deposits are reduced here due to the occurrence of long-lasting sedimentation gaps (hiatuses). The reconstruction of palaeoenvironment was carried out on the basis of pollen and lithological (loss on ignition, areometric) analyses along with more than 45 14C datings. In the Late Glacial sequences of the examined logs, mineral horizons interlaying organic deposits were affected by periodic climate warmings resulting in the permafrost melting during the Bolling and the Allerod Interstadials. In the Late Glacial deposits there are sequences (ca 0.5 m thick) deposited during the Older Dryas Stadial. The Allerod in the analyzed logs is bipartite: the lower sections (AL-1) are usually represented by peat deposition, whereas in the upper parts of the logs (AL-2) numerous minerogenic (clay, silty clay) inserts confirm the climate humidity growth (or permafrost melting) during the Gerzensee Oscillation. In the Late Glacial deposits, pollen of thermophilous trees, such as Corylus, Tilia, Quercus, Carpinus, as well as (typical for the Subboreal Phase) Abies alba and Fagus sylvatica occur, which may indicate the presence of thermophilous refugia in this part of the Carpathians. During the middle part of the Younger Dryas Stadial climate cooling, the widespread gradual increase in the delivery of allochthonous material to fens is related to permafrost melting. This process is finished by the deposition of clay and silty clay horizon at the beginning of the Holocene (Preboreal). The lack of the depositional sequences of the Boreal, Atlantic and partly the Subboreal phases in the majority of the logs is caused by the erosional removal of sediments during the climate humidity growth at the beginning of the Subboreal and the Subatlantic phases.

7th International Anthracology Meeting, University of Liverpool, UK, 2-6 Sept. 2019; International audience; Previous methodological developments in the field of anthracology have led to the definition of rigorous sampling methods in archaeological contexts, which provide highly accurate and reliable taxonomic frequency spectra as a basis for understanding past woodland vegetation. However, the fuelwood taxon frequency spectra represent a synthetic picture of forest composition in the environs of an archaeological site. Our aim in this paper is to describe the heterogeneity of woodland distribution. The Abeurador cave (Hérault) in the south of France, has previously provided an exceptionally rich palaeoecological study. We further explore the spatial frequency distributions of the charcoal taxa found in charcoal scatters from two layers dated to the Mesolithic (Preboreal). The frequencies of abundant taxa have a unimodal distribution in the sampled grid squares, close to the normal distribution. The ratio s2/m (variance/mean) termed the ‘distribution index’, estimates the regularity of distribution of each taxon in the grid squares. We hypothesized that the frequency distribution of a taxon in a layer could be considered to be its statistical sampling distribution (i.e. probability distribution) in the firewood collection catchment at a given time, since the quantity of this taxon fluctuates in each firewood assemblage according to its probability of collection, relating to its distribution heterogeneity (or accessibility) in the past environment. The distribution index was then used to estimate the heterogeneity of the palaeoenvironmental distribution of each taxon and thus its random, uniform or clustered distribution. On this basis, we propose a mapped restitution of the evolution of the main woodland species in the surroundings of the Abeurador during the Early Holocene, integrated with the whole sequence dynamics.; Les développements méthodologiques précédents de l'anthracologie ont conduit à la définition de méthodes d'échantillonnage rigoureuses en contexte archéologique, fournissant des spectres de fréquences taxonomiques précis et fiables comme base pour la compréhension de la végétation forestière passée. Les spectres de fréquence des taxons dans le bois de feu représentent une image synthétique de la composition des forêts aux alentours d'un site archéologique. Notre objectif dans cet article est de décrire l'hétérogénéité de la distribution des forêts. La grotte de l'Abeurador (Hérault), dans le sud de la France, a déjà fourni une étude paléoécologique exceptionnellement riche. Nous étudions ici la distribution spatiale, par mètre carré, des fréquences des taxons dans les charbons de bois dispersés de deux couches datant du Mésolithique (Préboréal). Les fréquences des taxons abondants ont une distribution unimodale dans les carrés de la grille d'échantillonnage, proche de la Loi normale. Le rapport s2/m (variance/moyenne), ou "index de distribution", estime la régularité de la distribution des fréquences de chaque taxon dans les carrés de la grille. Nous émettons l'hypothèse que la distribution de fréquence d'un taxon dans une couche pouvait être considérée comme sa distribution d'échantillonnage statistique (c'est-à-dire sa distribution de probabilité) dans l'aire de collecte du bois de feu à un moment donné, puisque la quantité de ce taxon fluctue dans chaque assemblage de bois de feu en fonction de sa probabilité de collecte, liée à son hétérogénéité de distribution (ou d'accessibilité) dans l'environnement du site. L'index de distribution est utilisé pour estimer l'hétérogénéité de la distribution paléoenvironnementale de chaque taxon et donc son patron de distribution aléatoire, uniforme ou groupée. Sur cette base, nous proposons une restitution cartographiée de l'évolution des principales espèces forestières dans les environs de l'Abeurador au cours de l'Holocène précoce, interprétée en fonction de la dynamique forestière de l'ensemble de la séquence.

On the basis of statistical analysis of craniometric data relating to Mesolithic and Neolithic samples from northern Eurasia, we discuss the peopling of the Baraba forest-steppe in the Early Holocene. This region is represented by samples from Sopka-2/1 (early sixth millennium BC), Protoka (late fifth to early fourth millennia BC), Korchugan (early-mid sixth millennium BC), and Vengerovo-2A (late sixth millennium BC). The results of the principal component analysis are interpreted in the context of debates over the role of autochthonous traditions in the Neolithic. During the Preboreal period (10 ka BP), large parts of the Baraba forest-steppe were flooded by the transgression of lake systems during climatic warming. This may have caused depopulation, lasting for at least a millennium. The Early Holocene people of Baraba were an offshoot of Meso-Neolithic populations of the northwestern Russian Plain. On that basis, the Early Neolithic populations of Baraba were formed. Direct population continuity is traceable only through the Chalcolithic. Since the late sixth millennium BC, however, the local population had incorporated migrants from the Pit-Comb Ware area in the central Russian Plain and, indirectly (via the Neolithic Altai), from the Cis-Baikal area.

Soft-sediment deformation structures have been indentified in glaciolacustrine deposits of the terrace complexes of the Lake Imandra (Kola Region, NE of the Fennoscandian Shield). According to the paleoseismological criteria, we found that these deformation structures were induced by strong earthquakes. These earthquakes led to the occurrence of secondary deformations of various morphology and sizes in the sandy-sandy sediments, forming a single complex consisting of intensely deformed and destructed deposits and associated clastic dikes and cracks. Among the plastic deformations, the phenomena of liquefaction, boudinage structures, flame structures, irregular convolute stratifications, diapir-like structures and synsedimentary folds are developed. Among brittle deformations, cracks and micro-fractures and dykes, predominate. The spatial and stratigraphic distributions of soft-sediment deformation structures were used to infer about the activation of faults during the Late Glacial and Postglacial period of the sub-latitudinal and north-western strike directions that limit the different-scale blocks of the earth’s crust. According to radiocarbon analysis data and paleogeographic reconstructions, the formation of soft-sediment deformations took place at the end of the Young Dryas – the beginning of the Preboreal period between 12900–11500 cal yr BP, and later, in the Preboreal period – beginning of the Boreal period between 11500– 9900 cal yr BP. It was this period that was accompanied by increased seismic activity not only in the Kola region, but also in the whole of Fennoscandia.

The results of studies of the Late Pleistocene and Holocene spore–pollen spectra and the microtheriofauna of loose deposits of four cave localities located in the Shchuger and Kozhym river basins within the territory of the Yugyd-Va National Park on the western slope of the Subpolar Urals are discussed. Assessment of the age of sediments from the karst cavities was based on the data of AMS radiocarbon dating of mammalian bones. The speleogenic formations of the localities studied contain layers assigned to the final stage of the degradation of the Polar Ural (Late Valdai) glaciation (Middle to Late Dryas) and to the Preboreal, Boreal, and Subatlantic periods of the Holocene. Cryoxerophilous tundra species predominated (88.3%) in the fossil microtheriofauna assemblage identified for the Allerod. The Middle Dryas and Allerod, the cold and warm periods of the Late Glacial, respectively, were reflected by the spore–pollen spectra. The microtheriofauna on the western slope of the Subpolar Urals remained quite cryophilous by the end of the Late Dryas. The broad distribution of yernik thickets and goosefoot–gramineous–mixed herb assemblages during that time has been established. The vegetation of the western foothills of the Subpolar Urals consisted of grass–shrub tundra with sparse spruce trees during the Late Preboreal cooling period. The microtheriofauna community also had a tundra-like composition. The presence of dark coniferous taiga forests in the south of the Subpolar Urals and sparse spruce–birch forests with pine and dwarf birch in the undergrowth in the north of the area during the Boreal period has been established. The rodent fauna acquired a forest-like character by that time. Northern taiga dark coniferous forests of spruce with a significant admixture of pine developed on the western slope of the Subpolar Urals by the middle of the Subatlantic period, and the content of tundra elements in the stands increased by the end of this period. The microtheriofauna of the studied region had a typical forest appearance characteristic of all Late Holocene taiga communities in northeastern Europe.

The Younger Dryas (12,680–11,590 yr BP) was the last millennial scale cold event of the Quaternary, when a mean annual temperature decline of 3–5 °C impacted severely on the environment. Whereas pollen distributions document changes in land vegetation, details of limnic ecosystem responses to the cooling event and to its recovery are still not well known. Here, we studied the laminated sediments of Lake Steisslingen (SW-Germany) deposited between 13,500 and 11,100 yr BP in order to investigate the evolution of an aquatic ecosystem. Bulk sediment and organic matter composition mark onset and termination of the Younger Dryas, but remain monotonous through this interval, requiring application of organic and isotope geochemical techniques to follow past ecosystem dynamics. The Younger Dryas is characterized by both an abrupt appearance and demise of long-chain alkenones indicative for haptophyte algae. Based on algal and bacterial biomarker distribution, the Younger Dryas can be divided into three stages, each characterized by the dominance of a microorganism group. The first phase was dominated by nC17 alkanes and hopanoids indicative of cyanophytes and heterotrophic bacteria. The second phase shows a proliferation of cold-adapted haptophyte algae, while in the latest phase highly-branched isoprenoids (HBI) reveal an aquatic community shift towards diatoms. Heterocyte glycolipids document a moderate change in N2-fixing cyanobacterial community structure over the Allerod/Younger Dryas transition but show a marked collapse of the cyanobacteria association at the Younger Dryas/Preboreal climate recovery. Terrigenic wax lipids indicate significant changes in vegetation between the Allerod, Younger Dryas and Preboreal chronozones but remain homogeneous within the Younger Dryas.

The main stages of the relationship between forest and steppe communities in the southern part of the Volga Upland have been reconstructed. The existence of primary (preagricultural) steppes of all types has been established. The landscape of this area changed as follows: the steppe landscape changed in the Preboreal and Boreal periods (10 300–7500 BP); the forest-steppe landscape (dominated by forests), in the Atlantic and Early Subboreal periods (7500–3200 BP); forest-steppe (dominated by steppes) and steppe landscapes, from the Late Subboreal period to the present (3200–0 BP); and the first agrocenoses appeared from 2500 BP.

Despite many ideas about the age and processes of sand movements and paleosol formation, there are still some uncertainties in this relations in the Nyírség, eastern Hungary. The major aim of the present study was to clarify the chronology of fossil soils and blown-sand layers in the sand dunes of the Nyírség using radiocarbon (14C) dating on soil and charcoal samples. Charcoal and soil samples were collected from buried paleosols from different sand quarries for 14C dating. The bulk organic carbon content of the buried soil and charcoal pieces recovered from buried fossil soil layers allowed parallel 14C accelerator mass spectrometry dating in several cases. The new 14C results indicate paleosol development during Younger Dryas, while the preceding interstadial was assumed as a cold and dry period when only sand movement occurred in the area. Our results also confirm and support the previous assumptions, that in the Late Glacial, the first paleosol development period was during the Bølling-Allerød Interstadial. Four soil-forming periods could be determined during the Holocene (Preboreal, Boreal, Atlantic, Subatlantic). We have also indirectly identified sand movements during the Oldest Dryas, Younger Dryas, Preboreal, Boreal, and Subatlantic phase in the study area.

This paper presents the first result of a study of two long-term natural archives in the southwestern part of the Western Siberian Plain. Bchron age models based on 17 AMS dates allowed us to determine a chronology of changes in properties of lake and peat deposits. Significant changes in the Holocene were identified according to geochemical indices, accumulation rates, and compositions of the plant macrofossils of sediment cores in Lake Kyrtyma and Oshukovskoe peat bog. Sediments with a low content of organic matter and maximum weathering accumulated in the Late Glacial, below the border of the Holocene. The transition to the Holocene manifested as a black organic gyttja with ostracods and marked warming ∼12–11.2 ka BP. At about 11.2–10.1 ka BP it was replaced by the Preboreal oscillation. Subsequent changes in lake sedimentation were associated with general warming and an unstable hydrological regime. An increase in humidification ∼8.2 ka BP was reflected by lake level rise and contributed to swamping of the watersheds. The aridest Holocene phase at ∼7.1–5.5 ka BP was reliably recorded by geochemical data, but poorly reflected in the stratigraphy of both profiles. Subsequent cooling and the resulting decrease in evaporation began at ∼5.5–4.9 ka BP. A pronounced cardinal shift in sedimentation conditions due to a gradual increase in precipitation was recorded at ∼4.9–2.8 ka BP, though short-term fluctuations towards dryness were also marked at ∼3.5–3.3 ka BP. The most significant increase in humidification and cooling began at 2.8 ka BP. Geochemical indices in the lacustrine sediments are climate sensitive and allowing us to obtain enough reliable data associated with changes in sedimentation environments. The stratigraphy of peat reflected the nuances of climatic changes less clearly and primarily demonstrated the stages of bog self-development; however, sphagnum peat provided a better-resolution record.

Undisturbed sediments are an important source for the reconstruction of the Holocene development of valleys. Wide floodplains with relatively small rivers in a region settled since 5500 BCE offer opportunities for investigations regarding climatic and anthropogenic landscape change. In the context of a motorway construction, excavations were carried out by the Saxonian Heritage Office in the year 2015. At one of the sites it was possible to get a view of the sediments of the Pleiße valley less than 100 m distance from large cross sections described by Neumeister (1964) in a former open cast mine. Archaeological finds and features, plant remains and radiocarbon dating as well as micromorphological and geochemical investigations helped to decipher the age and the characteristics of the Holocene sediments: above Weichselian loamy sands a sedge peat developed in small depressions during the Preboreal and Boreal. The sands and the sedge peat are covered by a “black clay”, which was still the topsoil during the Atlantic period. The sedimentation of 2.3 m thick overbank fines began after 4000 BCE. A depth of 1 m below the surface a medieval Slavic find layer was excavated. These results show that sedimentation processes in the lower Pleiße valley significantly changed after 4000 BCE. It is obvious that the increase in silty material in the floodplain is caused by the land clearance in the Neolithic period. More than half of the silty overbank fines were deposited before the Middle Ages began.

The Barents Sea offers a suitable location for documenting advection of warm and saline Atlantic Water (AW) into the Arctic and its impact on deglaciation and postglacial conditions. We investigate the timing, succession, and mechanisms of the transition from proximal glaciomarine to marine environment in the northwestern Barents Sea. Two studied sediment cores demonstrate diachronous retreat of the grounded ice sheet from the Kvitøya Trough (core S2528) to Erik Eriksen Trough (core S2519). Oxygen isotope records from core S2528 depict a two-step pattern, with lower δ18O values prior to the Younger Dryas (YD), and higher values afterward because of advection of the more saline,18O-enriched AW. At this location, subsurface AW penetration increased during the Allerød and YD/Preboreal transition. In the study area, foraminiferal and dinocyst data from the YD interval suggest cold conditions, extensive sea-ice cover, and brine formation, along with the flow of chilled AW at subsurface and the development of a high-productivity polynya in the Erik Eriksen Trough. Dense winter sea-ice cover with seasonal productivity persisted in the Kvitøya Trough area during the early Holocene, whereas surface warming seems to have occurred during the middle Holocene interval.

Causes of the Late Glacial to Early Holocene transition phase and particularly the Younger Dryas period, i.e. the major last cold spell in central Europe during the Late Glacial, are considered to be keys for understanding rapid natural climate change in the past. The sediments from maar lakes in the Eifel, Germany, have turned out to be valuable archives for recording such paleoenvironmental changes. For this study, we investigated a Late Glacial to Early Holocene sediment core that was retrieved from the Gemündener Maar in the Western Eifel, Germany. We analysed the hydrogen (δ2H) and oxygen (δ18O) stable isotope composition of leaf-wax-derived lipid biomarkers (n-alkanes C27 and C29) and a hemicellulose-derived sugar biomarker (arabinose), respectively. Both δ2Hn-alkane and δ18Osugar are suggested to reflect mainly leaf water of vegetation growing in the catchment of the Gemündener Maar. Leaf water reflects δ2H and δ18O of precipitation (primarily temperature-dependent) modified by evapotranspirative enrichment of leaf water due to transpiration. Based on the notion that the evapotranspirative enrichment depends primarily on relative humidity (RH), we apply a previously introduced “coupled δ2Hn-alkane–δ18Osugar paleohygrometer approach” to reconstruct the deuterium excess of leaf water and in turn Late Glacial–Early Holocene RH changes from our Gemündener Maar record. Our results do not provide evidence for overall markedly dry climatic conditions having prevailed during the Younger Dryas. Rather, a two-phasing of the Younger Dryas is supported, with moderate wet conditions at the Allerød level during the first half and drier conditions during the second half of the Younger Dryas. Moreover, our results suggest that the amplitude of RH changes during the Early Holocene was more pronounced than during the Younger Dryas. This included the occurrence of a “Preboreal Humid Phase”. One possible explanation for this unexpected finding could be that solar activity is a hitherto underestimated driver of central European RH changes in the past.

Summary We explored how the Younger Dryas (YD)/Holocene transition impacted tropical sea surface temperature (SST) by evaluating marine sedimentary archives at scales unattainable for conventional molecular stratigraphy. In sediments from the Cariaco Basin, we analysed the well-established UK’37 SST proxy via mass spectrometry imaging, and obtained 2D-images of sedimentary proxy distribution at 100 µm resolution and corresponding downcore SST profiles with subannual resolution. SST in the Cariaco Basin remains relatively constant over the YD/Holocene transition, suggesting a decoupling from the major environmental change associated to this event, i.e. the northward shift of the intertropical convergence zone. However, we were able to reveal a short-lived ∼50 year episode of abrupt warming during which average SST increased about 1°C. This episode is synchronous with the Preboreal Oscillation cooling, that led to drier, colder conditions in Europe and North America. The comparison of proxy values, elemental composition and sediment colour from every µm-sized spot further provides clues on SST seasonality and its modulation across the YD/Holocene transition.

This paper presents a comprehensive palaeoenvironmental data set from a trough between glacial curvilineations (an intra-GCL trough) of the Dobrzyn Lake District, north-central Poland. A sediment core taken from the depression was investigated to reconstruct Late Glacial and Holocene environmental changes in north-central Poland using a combination of palynological, macrofossil, sedimentological and geochemical studies. Four main development phases of the studied intra-GCL trough were distinguished. Accumulation of the analysed sediments occurred from the Late Vistulian (Glacial Phase) through the Late Glacial to present times. Our data suggest the persistence of dead ice in the basin up to the Older Dryas (Lacustrine Phase). The sedimentary record of the depression reflects a considerable difference between the Late Glacial/early Holocene and the middle/late Holocene in terms of environmental conditions. The Late Glacial was characterised by rapid environmental changes, while climatic conditions throughout the Holocene were relatively stable, except for the Subboreal period. A small lake was strictly dependent on climatically controlled vegetation changes and erosion tendencies in the vicinity of the Zbojenko site. The lake finally disappeared at the turn of the Younger Dryas and the Preboreal Period. The Preboreal, Boreal and Atlantic Periods encompassed the Early Paludical Phase, during which the water level used to rise and hence the mire could be flooded. The area was covered with dense vegetation and the rate of denudation processes around the site was moderate. The Late Paludical Phase included the Subboreal and most of the Subatlantic. Deciduous forests (with Quercus, Carpinus, Corylus) dominated around the site. Major changes occurred between the late Subboreal and the early Subatlanic as a result of the growing human impact on the environment. The Subatlantic ends with the human impact phase (Middle Age), dominated by human impact, little accumulation of sediments and highly increased denudation.

Palaeoecological studies in coversand areas are sparse as organic remains generally do not preserve well in sandy deposits. An AMS-dated Holocene peat sequence in a palaeochannel in a natural depression (the Liereman), flanked by coversand ridges proved to be an exceptional and valuable archive of long-term vegetation dynamics in the Campine (N Belgium). Analyses of microfossils, such as pollen, spores and non-pollen palynomorphs, as well as macrofossils of plants and other organisms have given insight in the vegetation dynamics over the past 11,500 years. Grasslands developed during the Rammelbeek phase of the Preboreal at the expense of the birch woodlands that characterized the Friesland phase of the Preboreal. During the Preboreal the depression was ecologically diverse with abundant resources for human subsistence, such as permanent fresh water, game and edible plants. However, to date no contemporaneous archaeological sites are known in the area. In the woodlands on the coversand ridges pines became the dominant regional vegetation towards the Boreal. The resulting lowering of ground water levels led to a decrease of the water availability and associated resources for hunter-gatherer societies. Yet, (early) Mesolithic hunter-gatherers settled in the area, however only temporarily. During the Atlantic coniferous forests were succeeded by mixed deciduous woodlands, while the freshwater availability decreased further. This possibly explains the near absence of middle and late Mesolithic sites in the Liereman area. From the Subboreal onward deciduous woodlands opened, probably as a result of human activity. Finally, through deforestation the area in and around the Liereman depression was partly cleared for agricultural purposes during the Subatlantic.

This chapter explores site-type variability in the course of the Early Mesolithic at the coast of central Norway. The Early Mesolithic was a period of great alterations in climate, landscape and oceanic environment. The Arctic conditions that prevailed on the coast when hunter-gatherers first arrived c. 9500, gradually gave way to a warmer climate. A cold pulse, known as the Preboreal oscillation (PBO), hit Scandinavia and Europe c. 9300–9200 cal bc, before the temperatures rose again. Midway through the Early Mesolithic period, c. 8800 cal bc, the ice melted away from all the large fjords and coastal waters, pushing the cold-tolerant fauna northwards. The parallel establishment of the Norwegian Atlantic Current provided stable and liveable conditions to a new range of marine species. For the coastal hunter-gatherers, these fluctuations must have greatly affected the resource base. Previous studies have pointed out that generalized toolkits and flexible mobility systems seem to have been ways of coping with the changing conditions. Was also site type an active variable of their adaptive strategy within this period? On the basis of Binford’s forager–collector continuum (1980), 18 sites are analyzed in terms of artefacts, tools, size, layout and features to see if there are diachronic trends in the frequency of different site types that can be related to the palaeoenvironmental trajectory of the period. The study points to a development from short visits when hunting activities and gearing up were the focus in the earliest part of the Early Mesolithic, to a more stable site pattern where residential bases were established near predictable food resources. This happens parallel with the environmental and climatic fluctuations, and it is likely that these trajectories are related.

In this study, we focus on the environmental changes recorded in the San River valley (Stubno–Naklo site, south-eastern Poland) at the beginning of the Holocene. This multi-proxy study for the first time in the region of the northern foreland of the Western Carpathians included quantitative thermal reconstruction based on Chironomidae and high-stratigraphic resolution of 14C AMS dating. We hypothesised that (i) climate events during the Early Holocene contributed to ecosystem turnovers via stimulating disturbances related to the river's fluvial activity and (ii) woodland and oxbow lake ecosystems became more resilient to flood disturbances along with the advance of forest succession on the floodplain. The results revealed that the response of ecosystems on the Early Holocene warming was strongly linked with the decrease in fluvial activity of the river. The reconstruction of the mean July temperature based on Chironomidae revealed the exceptionally high rate of warming during the period of ca. 11,490–11,460 cal. BP (at least 1 °C per decade) up to values > 2 °C than modern ones. During this period, the lake trophy and productivity started to increase with a simultaneous spread of Betula woodlands on the alluvial plain. The “Preboreal oscillation” cooling was dated at ca. 11,450–11,250 cal. BP. At that time, an increased climate instability led to a higher rate of extremal events such as flood at ca. 11,400–11,330 cal. BP, which probably led to the disruption of the Betula population. The development of riparian woodlands, initiated by the expansion of Ulmus from ca. 11,100 cal. BP, and further spread of Quercus and Fraxinus excelsior on the alluvial plain and lower river terraces increased plant transpiration and therefore limited the river runoff and its fluvial activity. This, together with the expansion of reed belt communities, probably limited the impact of floods on the oxbow lake. However, ca. 10,010–9880 cal. BP traces of higher fluvial activity, but of lower impact, were recorded.

Recent studies have shown that faunal assemblages from Mesolithic sites in inland Northern Europe contain more fish remains than previously thought, but the archaeological and archaeozoological record does not reveal the dietary importance of aquatic species to hunter-gatherer-fishers, even at a societal level. For example, the function of bone points, as hunting weapons or fishing equipment, has long been debated. Moreover, traditional methods provide no indication of variable subsistence practices within a population. For these reasons, paleodietary studies using stable isotope analyses of human remains have become routine. We present radiocarbon (14C) and stable isotope data from nine prehistoric human bones from the Early Mesolithic-Early Neolithic site of Friesack 4, and isotopic data for local terrestrial mammals (elk, red deer, roe deer, wild boar, aurochs, beaver) and freshwater fish (European eel, European perch). The reference data allow individual paleodiets to be reconstructed. Using paleodiet estimates of fish consumption, and modern values for local freshwater reservoir effects, we also calibrate human 14C ages taking into account dietary reservoir effects. Although the number of individuals is small, it is possible to infer a decline in the dietary importance of fish from the Preboreal to the Boreal Mesolithic, and an increase in aquatic resource consumption in the Early Neolithic.

The studies aimed to reconstruct major phases of litho-morpho-pedogenic processes and past environmental changes in the Baltic coastal zone near Poddąbie (54°37,070′ N, 16°57,897′ E) based on physical, chemical, pollen, and fossil Cladocera analysis of the polycyclic pedocomplex. The polycyclic pedocomplex under study included seven fossil soils developed from the Early Holocene until modern times from various materials. The soils were sampled and analyzed using standard procedures in soil science to determine their physical and chemical properties. Pollen and fossil Cladocera analysis was also carried out in the examined profile. Radiocarbon dates of selected samples were also specified. The studied polycyclic pedocomplex has been developed from materials of varied origin, including glaciofluvial, fluvial, aeolian, and biogenic deposits of the lake. According to the results of pollen and fossil Cladocera analysis and radiocarbon dating, this body of water has evolved from the beginning of Preboreal period to the half of Boreal. The studied soils represent various reference groups and advancement of development. They constitute relics of former geomorphological and soil-forming processes, which have taken place over the last 9500 years, including periglacial processes, wildfires, Baltic Sea shoreline changes, and aeolian activity. The last stage of the coastal relief dynamics was conditioned by the fire which took place about 1472–1637 AD. The lack of plant cover and intensive abrasion due to direct vicinity of the coastline has caused the deposition of aeolian material, which is the parent material of nutrient-poor initial soils. The analysis of fossil soil development with the use of specialized research methods allowed for reconstructing the dynamics of past geomorphological processes and natural environment changes in the study area. The studied polycyclic pedocomplex constitutes a record of environmental changes taking place in the central part of the Polish Baltic coastal zone from the Early Holocene to the present day. The studied soil sequence is located within a land depression developed in place of the former water reservoir created as a result of permafrost degradation, and filled with Holocene deposits.

The multi-proxy data (pollen, diatoms, Cladocera, 14C) from the sediments of Lake Suchar Wielki representing the period ca. 11,600–9800 cal. BP have allowed the reconstruction of the influence of Preboreal cold oscillations on terrestrial and aquatic environments in NE Poland. The reconstructed changes in plant, cladoceran and diatom communities indicated an occurrence of four short-lasting negative climate events during the Preboreal period. The first three of them occurred in the early Preboreal (ca. 11,300–11,150, 11,100–11,000 and 10,900–10,850 cal. BP) and they were separated by short, warmer intervals. The obtained palynological data indicated that these events did not result in the transformations of the pine-birch forests strongly dominant in that period, but were only manifested by changes in the pollen production by the trees forming woodstands. In the lake during these coolings, cold-water Cladocera species developed, and the abundance of aquatic organisms decreased. Water level in the lake during two older early-Preboreal cold events increased significantly, and remained low during the last event. In the late Preboreal a fourth cooling took place. The cold peak was relatively short (ca. 10,300–10,200 cal. BP), but was preceded by a ca. 300-year-long period when conditions for plants were unfavourable. The drop in temperature was accompanied by a decrease in the humidity of the climate and a decrease in the water level in the lake. Again, the abundance of cold-water species increased. The acreage covered by pine decreased, and a temporary spreading of birch occurred. This last cold event in the Preboreal was followed by a relatively stable warm phase at the end of this chronozone. The recorded climate changes in NE Poland during the Preboreal correspond fairly well with those reported for other regions of Europe and the whole Northern Hemisphere.

The rate and magnitude of temperature variability at the transition from the Last Glacial Maximum into the early Holocene represents a natural analog to current and predicted climate change. A limited number of high-resolution proxy archives, however, challenges our understanding of environmental conditions during this period. Here, we present combined dendrochronological and radiocarbon evidence from 253 newly discovered subfossil pine stumps from Zurich, Switzerland. The individual trees reveal ages of 41–506 years and were growing between the Allerod and Preboreal (∼13′900–11′300 cal BP). Together with previously collected pines from this region, this world's best preserved Late Glacial forest substantially improves the earliest part of the absolutely dated European tree-ring width chronology between 11′300 and 11′900 cal BP. Radiocarbon measurements from 65 Zurich pines between ∼12′320 and 13′950 cal BP provide a perspective to prolong the continuous European tree-ring record by another ∼2000 years into the Late Glacial era. These data will also be relevant for pinpointing the Laacher See volcanic eruption (∼12′900 cal BP) and two major Alpine earthquakes (∼13′770 and ∼11′600 cal BP). In summary, this study emphasizes the importance of dating precision and multi-proxy comparison to disentangle environmental signals from methodological noise, particularly during periods of high climate variability but low data availability, such as the Younger Dryas cold spell (∼11′700 and 12′900 cal BP).

We provide new data on the Black Sea evolution during the preconnection and reconnection stages with the Mediterranean, based on sedimentology, geochemistry, calcareous nannoplankton and ostracods analysis, in 13 cores placed between 141 m and 1315 m water depths. Unit 1 – The Coccolith Mud, Unit 2 - The Sapropel Mud and Unit 3 – The Lacustrine Lutite, including red-brownish depositional intervals, were identified in all studied deep-water cores. These units are not present in a shallow setting, i.e., above 166.7 m water depth, being replaced by sandy levels and shell debris. The red-brownish layers are interpreted as hyperpycnites, but some of the red successions show turbidite features, especially the ones situated on canyon sides, at a water depth below 600 m. In the oldest intercepted Unit 3 of the Neoeuxinian lake, CaCO3 values are constantly low, but towards the top of this unit they show two distinct peaks, interpreted as signals of Bolling–Allerod and Preboreal interstadials. In between, a significant decrease in CaCO3 values, linked to the setting of the Younger Dryas, is coincident in the deep cores with diatom blooms and high frequency of ostracods related to cooler waters. The scarce but continuous occurrence of Emiliania huxleyi nannoplankton species from the top of Unit 3 indicates that the salinity was at least 10–11‰ prior the Sapropel Mud deposition and increase at a least 17‰ within the lower part of Unit. 2. In the same interval, the Ponto-Caspian ostracods are still present. The Mediterranean ostracods consistently occur from the top of Unit 2, when bottom water salinity reached values for allowing their survival. The first bloom of E. huxleyi is placed at the base of Unit 2, where coccolith laminae occur, while the second bloom is placed in Unit 1 that contains exclusively Mediterranean ostracods and consistent assemblages of benthonic foraminifers, similar with the ones present today.

Представлены новые данные по литологии, микропалеонтологии и геохронологии донных осадков малых озер, расположенных на западном берегу Онежского залива Белого моря. На основе полученных данных для указанного района реконструирована палеогеографическая обстановка позднеледниковья и голоцена. Установлено, что здесь в позднем дриасе в условиях краевой зоны деградирующего ледника образовывались приледниковые озера. Их осадки в виде палеонтологически немых разнозернистых песков с гравием отмечены в некоторых котловинах побережья до высоты около 140 м над у.м. Спуск этих озер в конце позднего дриаса способствовал формированию единого обширного пресноводного водоема в котловине современного Онежского залива. В начале пребореала при таянии погребенного льда на прилегающей суше происходило заболачивание локальных депрессий и образование низинных болот и торфяников. В конце пребореала - начале бореала при замедлении гляциоизостатического поднятия земной коры, после разрушения ледяной преграды в районе Соловецких островов и притока морской воды в котловину Онежского залива произошло затопление прилегающей к нему территории. Сначала в этом обширном водоеме, а позже в отделившихся от него малых озерах накапливались слоистые алевриты и алевритистые сапропели, перекрывающие торф в разрезах донных отложений. Котловины малых озер отчленялись от основного водоема Онежского залива в разное время на протяжении голоцена по причине гляциоизостатического поднятия и восходящих блоковых движений земной коры.

The Harz Mountains are Germany's northernmost low mountain range. The southern foreland is characterised by a fragmentary distribution of loess and loess-like deposits. During prehistoric times this region was sparsely populated, in contrast to the adjoining southern floodplain of the Helme River, which has been a favoured settlement area since the Neolithic period. This study focusses on the onset of human impact on the landscape and aims to reconstruct the landscape development of this peripheral prehistoric settlement area under a long term perspective (Lateglacial to Late Holocene). The study is based on the sedimentological analysis of six sediment profiles from the floodplain of two small valleys. The chronology of the sedimentological records is provided by 24 new AMS radiocarbon ages that range from 21.7 ka BP to 0.1 ka BP. Three major changes in the depositional environment are observed in the sediment records representing the landscape evolution: a) During the Lateglacial, periglacial conditions prevailed and deposition and reworking of loess occurred on the slopes, while in the floodplains periglacial cover beds and alternating partly gravelly layers of silts and clays were deposited. b) From Preboreal to Atlantic periods a marked rise in the groundwater table led to authigenic precipitation of carbonates in the floodplains under ameliorated climatic conditions. During this phase the valleys were progressively filled by intercalated organogenic and calcareous sediments. c) Human influence on the landscape is reflected in colluvial and alluvial deposits indicating the occurrence of human-induced soil erosion and is dated prior to the beginning of the Bronze Age (here corresponding to Subboreal period). During the period of the Little Ice Age gully incision occurred, probably as a result of an intensified land use in upslope areas and of high-magnitude precipitation events during this period.

New data on the structure and geomorphological features of the geological pattern of the Zimniy Coast (Dvina Bay, White Sea) from Keretsky cape to Kuya river was obtained using methods of geomorphological profiling, lithostratigraphic descriptions, radiocarbon dating and diatom analysis, and the history of the relief development of the bottom and coast of the Dvinsky Bay in the Late Glacial and Early Holocene was reconstructed. An approximate estimation of the relative sea level change and the relative vertical movements of the coast is given. It has been established that on the northeastern shore of the Dvina Bay, terraces of 5–20 m height were formed earlier than 9030 ± 80–8410 ± 40 14C (~10.2–9.4 ka cal) years BP, during the Lateglacial transgression, the amplitude of which, according to the approximate estimation, did not exceed 15– 16 m relative to the modern sea level. The north-eastern coast of the Bay (the Zimniy Coast) underwent relative elevation at a rate of about 0.2–0.5 mm/year, less than the Letniy Coast, which cannot be explained only by glacioisostasy. The Severnaya Dvina river delta was relatively stable. At the end of the Preboreal – the beginning of the Boreal, a sea regression occurred on the shores of the Bay, followed by the sharp increase of the Barents Sea waters inflow into the Bay.

The stratigraphic sequence, archaeological content, and location of Cuze de Sainte-Anastasie (Cantal, France), also known as Cuze de Neussargue, makes the site of key importance for clarifying the cultural identities and mobility strategies of Laborian and Mesolithic hunter-gatherers in the heart of the Massif Central. The re-evaluation of the site’s lithic assemblages presented here has the dual goal of integrating technological and economic behaviours of these human groups using different forms of evidence (petro-archaeological, techno-typological, functional) within the context of a general revision of the site’s archeostratigraphy. This approach also allows for a better understanding of previous assemblages (the Pierron and Rozoy collections) recovered from the site. The site is situated at 900 metres a. s. l. on the eastern slopes of the Cantalian Massif in the commune of Sainte-Anastasie (Cantal) and comprises two small, adjacent rockshelters developed in volcanic tuffs underlying a thick basalt flow forming an imposing 100 metre-high cliff. Discovered in 1945, subsequent excavations by R. Pierron, H. Derville and R. Rey, who concentrated on the southern rockshelter, identified a three-metre-thick succession of archaeological levels spanning the Mesolithic to Middle Ages. Two decades later, J.-G. Rozoy directed small-scale excavation in front of the rockshelter which yielded little archaeological material but better documented the lower levels identified by Pierron. Finally, A. Delpuech and P. Fernandes worked at the site between 1981 and 1985 following clandestine excavations. After disappointing results for the area in front of the southern rockshelter, work on the porch of the northern cave uncovered stratified Mesolithic and Late Palaeolithic occupations. In order to re-evaluate both the sequence and associated lithic material, we assembled a multi-disciplinary team as part of a project to produce a site monography., La rareté des stratigraphies livrant du Paléolithique final et du Mésolithique fait du Cuze de Sainte-Anastasie (Cantal, France) un site important pour préciser les identités culturelles et les stratégies de mobilité mises en oeuvre par les chasseurs-collecteurs de cette période entre Pléistocène et Holocène. L’objectif de ce travail de réévaluation des industries lithiques est de documenter les comportements des groupes humains au travers des différents volets pétrographique, technologique, typologique et fonctionnel. Le gisement, situé à 900 m d’altitude sur le versant est du massif cantalien, est constitué de deux abris contigus creusés aux dépens de brèches volcaniques. Découvert en 1945, les premières fouilles sont réalisées par R. Pierron, H. Derville et R. Rey qui identifient une succession d’occupations allant du Mésolithique au Moyen-Âge. Vingt ans plus tard, J.-G. Rozoy mène des fouilles limitées devant l’abri sud. Enfin, à la suite de fouilles clandestines, les travaux reprennent à partir de 1981, menés par A. Delpuech et P. Fernandes, permettant de retrouver devant la grotte nord des occupations du Mésolithique et du Paléolithique final. La réévaluation archéostratigraphique des dernières fouilles conduit à discriminer cinq unités archéostratigraphiques (UA). Nous ne traitons pas ici du premier ensemble (UA 1) rapporté pro parte au Néolithique final. Les UA 2 et 3 livrent des assemblages lithiques pauvres pouvant néanmoins être attribués au Mésolithique. Les UA 4 et 5 appartiennent au Laborien. Concernant ces dernières, l’hypothèse fonctionnelle indique deux modes d’occupation différents du site au cours du Laborien récent. L’UA 4 est marquée par une pauvreté en armatures lithiques, l’existence d’activités liées à la boucherie et un litho-espace recentré régionalement. L’UA 5 se différencie par une abondance en pointes lithiques, un travail des matières végétales et un litho-espace étendu jusqu’à 200-250 km du site. De plus, l’hypothèse d’un premier passage de groupes du Laborien ancien, à la base de l’UA 5, demeure envisageable., Langlais Mathieu, Delvigne Vincent, Gibaud Alix, Jacquier Jérémie, Perrin Thomas, Fernandes Paul, Delpuech André. La séquence archéostratigraphique du Cuze de Sainte-Anastasie (Cantal) : variations diachroniques et synchroniques des industries lithiques du Laborien au Mésolithique. In: Bulletin de la Société préhistorique française, tome 115, n°3, 2018. pp. 497-529.

Atmospheric relative humidity is an important parameter affecting vegetation yet paleo-humidity proxies are scarce and difficult to calibrate. Here we use triple oxygen ( δ 17 O and δ 18 O) and hydrogen (δD) isotopes of structurally-bound gypsum hydration water (GHW) extracted from lacustrine gypsum to quantify past changes in atmospheric relative humidity. An evaporation isotope-mass-balance model is used together with Monte Carlo simulations to determine the range of climatological conditions that simultaneously satisfy the stable isotope results of GHW, and with statistically robust estimates of uncertainty. We apply this method to reconstruct the isotopic composition of paleo-waters of Lake Estanya (NE Spain) and changes in normalized atmospheric relative humidity ( RH n ) over the last glacial termination and Holocene (from ∼15 to 0.6 cal. kyrs BP). The isotopic record indicates the driest conditions occurred during the Younger Dryas (YD; ∼12–13 cal. kyrs BP). We estimate a RH n of ∼40–45% during the YD, which is ∼30–35% lower than today. Because of the southward displacement of the Polar Front to ∼42°N, it was both windier and drier during the YD than the Bolling–Allerod period and Holocene. Mean atmospheric moisture gradually increased from the Preboreal to Early Holocene (∼11 to 8 cal. kyrs BP, 50–60%), reaching 70–75% RHn from ∼7.5 cal. kyrs BP until present-day. We demonstrate that combining hydrogen and triple oxygen isotopes in GHW provides a powerful tool for quantitative estimates of past changes in relative humidity.

This paper explores environmental variations in time and space, adaptive strategies and possible cultural responses to climatic changes as manifested through archaeological data in terms of lithic tool technology, site density and settlement patterns. The objective is investigated by two case studies from Mesolithic Norway. The first case deals with the earliest settlement phase of Norway (c. 11,500–10,000 cal. BP), which climatically encompasses gradual changes from cold, arctic conditions, to a milder sub-arctic climate, as well as the rapid Preboreal Oscillation (PBO) cold event. The second case explores the 8200 cal. BP cold event and its effect on culture and settlement in Southeast Norway. The studies suggest that the coastal settlement, in terms of site density, was not affected by either the PBO or the 8200 cal. BP event. Changes in site location patterns seem to have occurred gradually and on a long-term scale. Shifts in lithic technology are detected within the Mesolithic periods, but a correlation between abrupt climatic alterations and cultural changes are yet to be proved. We argue, therefore, that in these northern, coastal environments, declining temperatures may have had less impact than on the Continental Plains, and may in fact have improved the living conditions for a range of marine species. Also, the Mesolithic populations seemed to have employed a generalized lithic toolkit and a flexible mobility system – adaptive strategies that was able to withstand environmental variations in time and space. Breivik, Heidi Mjelva, Guro Fossum, and Steinar Solheim. "Exploring human responses to climatic fluctuations and environmental diversity: Two stories from Mesolithic Norway." Quaternary International (2017). © 2017. This manuscript version is made available under the CC-BY-NC-ND 4.0 license.

This paper presents the results of multi-disciplinary research carried out on the deposits of a residual channel (“Peerdemeers”) of the Kale/Durme River in the Moervaart depression, NW Belgium. The combination of physical, botanical, zoological and chemical analyses allowed a detailed reconstruction of the channel ecosystem and the vegetation in the surrounding landscape during the Younger Dryas and Early Holocene. A chronology for the record was provided by radiocarbon dating. Vegetation patterns were influenced by major climate changes that occurred during this period. During the early Younger Dryas, the river channel was active and vegetation was open with scattered birch copses, shrubs, grasses and herbs. The channel was cut-off in the late Younger Dryas, while some heath developed in the area. The Friesland Phase is characterised by a lithological change and increase in water level in the residual channel. Dwarf birch disappeared and boreal forests developed. The area however, remained relatively open compared to other coversand areas in NW Europe. The Rammelbeek Phase is considered as a drier, more continental climate phase in which forest expansion was temporarily interrupted and grasslands became more abundant. Also at the “Peerdemeers” site an increase in grasses is recorded. During the entire period (ca. 1,000 years) there is no hard evidence for human activity. The absence of archaeological evidence is in sharp contrast with the preceding (Allerod) and succeeding periods (Boreal). This suggests that environmental conditions during the YD and PB were probably too unfavourable for hunter-gatherers to remain in the Moervaart area.

Archaeological fieldwork preceding housing development revealed a Mesolithic site in a primary context. A central hearth was evident from a cluster of calcined flint and bone, the latter producing a modelled date for the start of occupation at 8220–7840 calbcand ending at 7960–7530 calbc(95% probability). The principal activity was the knapping of bladelets, the blanks for microlith production. Impact-damaged microliths indicated the re-tooling of hunting weaponry, while microwear analysis of other tools demonstrated hide working and butchery activity at the site. The lithics can be classified as a Honey Hill assemblage type on the basis of distinctive leaf-shaped microlithic points with inverse basal retouch.Such assemblages have a known concentration in central England and are thought to be temporally intermediate between the conventional British Early and Late Mesolithic periods. The lithic assemblage is compared to other Honey Hill type and related Horsham type assemblages from south-eastern England. Both assemblage types are termed Middle Mesolithic and may be seen as part of wider developments in the late Preboreal and Boreal periods of north-west Europe. Rapid climatic warming at this time saw the northward expansion of deciduous woodland into north-west Europe. Emerging new ecosystems presented changes in resource patterns and the Middle Mesolithic lithic typo-technological developments reflect novel foraging strategies as adaptations to the new opportunities of Boreal forest conditions. While Honey Hill-type assemblages are seen as part of such wider processes their distinctive typological signature attests to autochthonous, regional developments of human groups infilling the landscape. Such cultural insularity may reflect changing social boundaries with reduction in mobility range and physical isolation caused by rising sea level and the creation of the British archipelago.

To trace spatial variations in Holocene reservoir ages of surface and subsurface waters we studied narrowly spaced 14C records of planktic foraminifera in three high-sedimentation rate cores from the Nordic Seas, the Barents Sea continental margin and eastern Fram Strait. The two northern cores reveal a distinct Early Holocene 14C plateau in dates on the subsurface dweller Neogloboquadrina pachyderma at 9.3–9.1 14C ka. The plateau was tuned to an atmospheric 14C plateau at 9.0–8.7 14C ka that spans 10.2–9.6 calendar ka. These two plateau boundaries provide robust age control points to estimate short-term changes in sedimentation rate and to correlate paleoceanographic signals over 900 km along the West Spitsbergen Current. The difference between planktic and atmospheric 14C plateau ages suggests local 14C reservoir ages of 370–400 yr. Planktic foraminifera species that inhabit different water masses document different reservoir ages. By comparison, the subpolar N. incompta reveals a reservoir age of 150 yr, probably formed in well-mixed Atlantic-sourced waters during winter. The near-surface dweller Turborotalita quinqueloba shows an age of 290 yr in the Fram Strait, but one of 720 yr at the Barents Sea continental margin. The latter age suggests a calcification within old, meltwater-enriched Arctic surface waters admixed by the East Spitsbergen Current. Likewise, we assign an elevated reservoir age of 760 yr on mixed species at a Norwegian Sea site near 71°N to Preboreal meltwaters that spread from northern Norway far west, also documented by the spatial distribution of a coeval δ13C minimum of N. pachyderma.

Stable isotopic measurements on the upper 168 cm of stalagmite DG24 from southern China, which is annually-laminated above 74.8 cm (∼11.8 ka), reconstruct a history of detailed Asian summer monsoon (ASM) variability and soil processes between 14.8 and 10.3 ka. The climate sequence of Bolling-Younger Dryas (YD)-Preboreal events is evident in δ18O record. In the Preboreal, four-year-resolution and annually-counted δ18O record reveals that the ASM strengthening can be divided into three phases, with a prominent and persistent rise initiated at about 11.2 ± 0.3 ka, likely in response to interactions between ocean, atmosphere, and ice sheets. In contrast, the long-term δ18O depletion is absent in the δ13C and annual layer records, which characterize persistent centennial oscillations and likely represent relative humidity of the soil. At multi-decadal scale, prominent ASM failures are generally consistent with periods of δ13C enrichment and decreased layer thickness. When compared with solar proxies, centennial-scale δ13C changes match well with solar activity regardless of the observed disparity between ASM and solar records, and common cycles of 130 and 300 years are identified in both the atmospheric Δ14C and speleothem δ13C records. This implicates that during the Preboreal local soil humidity budget and CO2 production, indicated by the δ13C and annual layer records, is more sensitive to changes in solar output than the regional hydroclimate variability recorded by the δ18O signal.

Transitions of glacial-interglacial cycles are critical periods for Quaternary climate shifts. Here, we present new, decadal resolution Asian summer monsoon (ASM) record from three stalagmites obtained from the Dark Cave in southwestern China over 130–114 thousand years ago (ka, before CE 1950). Chronology was anchored by 28 230Th dates with typical uncertainties of ±0.3–1.0 kyr, allowing an assessment of timing and transition of climate changes during the onset and end of the last interglacial. An agreement between this new and previous stalagmite δ18O records supports that summer insolation predominates orbital-scale ASM evolution. A 2–3 kyr-long gradually increasing ASM period, analogous to the classical Preboreal episode in the early Holocene, follows the termination of a weak monsoon interval at 129.0 ± 0.8 ka. This finding suggests a strong influence of high-latitude ice-sheet dynamics on Asian monsoonal conditions during the early interglacial period. An abrupt end of the marine isotope stage 5e at 118.8 ± 0.6 ka was probably caused by the internal climate system threshold effects.

We report on the changing radiolarian faunas from the Younger Dryas (ca.12.9 calibrated thousands of years BP [cal. Ky BP]) and into the Holocene (ca. 10.3 cal. Ky BP) in the core JM99-1200 from Andfjorden, northern Norway. Temperature reconstructions using both the Q-mode factor analysis and modern analogue technique methods show stable, cold temperatures below ca. 410 cm core depth, followed by abrupt warming into a relatively stable Holocene temperature regime. Age-depth modelling with three different methods gives an age of ca. 11.9–12.0 cal. Ky BP at this core depth, clearly older than the Younger Dryas–Holocene transition at ca. 11.65 cal. Ky BP according to ice core chronology. Considering that the age models may be insufficiently informed in an interval without radiometric dates, it is possible that the base of the Holocene is indeed at 410 cm, as indicated by the radiolarian and other core data. Such a change in the chronology would have implications for previously published work on the JM99-1200 core. Alternatively, the abrupt warming in Andfjorden predated the Younger Dryas–Holocene transition by a few hundred years. A distinct cold pulse at ca. 315–335 cm, or 11.4–11.5 cal. Ky BP is interpreted as the Preboreal Oscillation. The Preboreal Oscillation has not previously been detected in temperature curves based on planktic foraminifera in the same core, indicating that Radiolaria may be a more sensitive temperature indicator in this region.

The Vistytis Upland is a terminal moraine ridge featuring kame hills. There are numerous lakes and wetlands in its depressions. We collected the samples of bottom sediments from a number of lakes and wetlands located at different altitudes. Using the results of the lithological analysis and radiocarbon dating of the lakes’ bottom sediments and those of a loss-on-ignition test, we identified the main stages of sedimentation. We reconstructed the formation and development of the lakes of the Vistytis Upland from the moment of deglaciation to the present. Two groups of lakes were distinguished by genesis: (a) the lakes formed in the inter-moraine or inter-kame depressions flooded by melt water; (b) the lakes formed in the thermokarst processes. The lakes of the first type are located at altitudes over 170 m and date back to the Younger Dryas, whereas the lakes of the second type are located below 170 m and their formation occurred in the Younger Dryas—the Preboreal. We conclude that the wetlands located west of Lake Vistytis were the bays of the lake in the Late Pleistocene.

Changes in water circulation in the Bering Sea have profoundly impacted biological productivity, carbon cycle and global ocean circulation, especially from the last deglaciation to the Holocene. Grain size and clay mineral composition were investigated in core ARC6-B10, collected from the northern Bering slope, in order to reveal changes in circulation and sediment provenance since the late deglaciation (~13.7 ka). The results highlight changes in sea level and atmospheric circulation as the primary controls on the variations in grain size and clay mineralogy. Deglacial sea level rise deepened the water passages along the Aleutian Arc, enhanced the inflow of North Pacific water that strengthened the circulation of the Bering Sea, and receded the coastline. These changes increased the supply of smectite-enriched sediments from the Aleutian Islands to the core site. A temporary reduction in smectite and an increase in the illite and chlorite contents during the Preboreal period correspond to the opening of the Bering Strait; this is attributed to rapid sea level rise which resulted in increased sediment resuspension from the shelf. During the mid- to late Holocene, when the sea level stabilized, changes in the Aleutian Low (AL) were a major factor modulating changes in ocean circulation. A weakened AL in the mid-Holocene intensified the northward Bering Slope Current and the increased the flow through the Bering Strait, while an intensified AL, along with an expanded sea ice cover during the late Holocene may have weakened the northward flow.

Bottom sediments from Lake Okunozero, located in front of Syamozero marginal formations, were analyzed to better understand the degradation conditions of the Last Glaciation in South Karelia at the Neva (Syamozero) stage and to assess the effect of climate on environmental changes. Paleogeographic reconstructions are based on the study of lake sediments using an integrated approach, which comprises spore-and-pollen, diatom and radiocarbon (14C) analyses. More evidence was obtained for the Late Glacial deposition pattern, the environmental conditions and evolution dynamics of the proglacial ice lake directly contacting the ice margin and of vegetation in that period. For the first time, Lake Glacial sediments were found to contain over 30 redeposited marine diatom alga species and varieties, not reported earlier from rock sequences of that period. The lake separated from the periglacial water body at the end of the Late Dryas. Its evolution after separation from the proto-Onega was traced, evolution stages were recognized, and more light on was shed the paleogeographic conditions in the surrounding area. The vegetation dynamics from the Allerod to the present day was reconstructed. In the Late Glacial Period the study area was occupied by tundra dwarf birch-true moss, sagebrush-wormwood periglacial-steppe and forest-tundra paleocommunities. Meadow-like tall-herb communities and birch forests with an admixture of pine appeared in the Preboreal. In the Boreal time, light-coniferous pine forests with an admixture of birch occupied the area, to be replaced in the Atlantic period by pine-spruce forests with the participation of broad-leaved species. Since the Subboreal, spruce and pine-spruce forests have prevailed in the study area. We observed that diatoms were missing from some horizons in almost every paleoclimatic period and suggested possible explanations for these gaps.

We present a new chironomid record from sediments of former Lake Svarcenberk in South Bohemia (412 m asl, Czech Republic), located in the oceanic-to-continental macroclimatic transitional zone of eastern Central Europe. We provide estimates of Weichselian Late Glacial and Early Holocene (ca. 15–8 ka BP) mean July air temperatures on the basis of changes in the fossil assemblage using a joint Norwegian-Swiss transfer function. In our study, the climate was found to be relatively cold during the Late Pleniglacial, with July temperatures ranging between 11.2 and 12.3 °C. With the exception of the youngest section of this interval, temperatures during the Bolling-Allerod interstadial were relatively stable and warm, with values around 13.3–14.5 °C. During the Younger Dryas (YD), July temperatures varied between 12.7 and 16 °C, and these particular results are in agreement with other climatic reconstructions from the central to the eastern part of the European continent showing no or moderate summer temperature decrease during the YD, or even a slightly warming trend. A relatively warm and climatically stable early YD phase was followed by a variable and overall cooler younger phase. At the beginning of the Early Holocene, our reconstructed July temperatures increased to 17.7 °C. We demonstrate that general patterns of temperature changes inferred from chironomids during the Last Glacial Termination are similar to various multi-proxy reconstructions in Europe but we observe two unusually strong and abrupt cooling events: one that may be linked with the Gerzensee oscillation at the end of the Bolling-Allerod Interstadial and another that probably corresponds to the Preboreal Oscillation, although the temperature decreases in these intervals were much more pronounced than observed in other chironomid records from Europe, suggesting that local climatic factors and ecosystem responses may have overamplified these cold events in the temperature reconstruction. However, other proxies (geochemistry, pollen) support the interpretation of climatically driven palaeoenvironmental changes such as the development of vegetation cover, changes in lake productivity, pedogenesis and erosion.

Inland dune fields have recently emerged as a source of data for reconstructing paleoenvironments and climate in the western Great Lakes region of North America during the Pleistocene-Holocene transition. We employ optically stimulated luminescence (OSL) methods, radiocarbon ages, soils, and landform relationships to determine the age of inland dunes in Ottawa County, Michigan. These dunes rest on the abandoned bed of Glacial Lake Chicago, which is thought to have been exposed after ~13.6 ka. OSL analyses from two inland dunes yield ages ranging from 13.3±1.1 to 11.6±0.9 ka (uncertainty=2σ). Fine sand in the parabolic dunes suggests deflation of exposed glaciolacustrine nearshore sand by northwesterly and westerly winds. These new data add to a growing number of studies that demonstrate widespread eolian activity in the western Great Lakes region during the Pleistocene-Holocene transition. OSL ages from dune fields in the western Great Lakes indicate peak eolian activity and dune stabilization occurred during or following the Younger Dryas and Preboreal events. Northwesterly and westerly winds suggest the limited effect of hypothesized easterly anticyclonic winds during the Pleistocene-Holocene transition. Rapidly changing climate and newly deglaciated surfaces provided an ideal environment for dune formation.

There have been several studies addressing the timing and extension of Late Pleistocene and Holocene Aeolian activity in the Nyirseg, the former alluvial fan of the Tisza River. Some of these already applied numerical dating techniques, however usually focused on one dune form or one site. This paper is an attempt on the one hand to review former age data and on the other hand to add new data from various sites to the landform evolution of the second largest sand dune area of the Carpathian Basin. The paper focuses on the Late Pleistocene–Holocene landform evolution of the second largest sand dune area of Hungary (Nyirseg). Recent age data were obtained from investigations applying several methods (radiocarbon, OSL and palynological examinations) in order to determine the periods of sand movement and paleosoil formation in the area more accurately. According to the results, six sand movement periods can be identified during the Late Glacial and Holocen (Oldest Dryas, Younger Dryas, Preboreal Phase, Boreal Phase, Atlantic Phase, Subatlantic Phase). In between periods with intensive aeolian activity paleosoil formation occurred in the Bolling-Allerod Interstadial and in the Preboreal and Subatlantic Phases.

Major changes in the Holocene were identified based on a diatom and geochemical analysis of sediment cores from Lakes Ufimskoe and Syrytkul (the Southern Urals). The Lake Ufimskoe ecosystem in the Central mountain area is identified to be highly sensitive to variations in temperature. Meanwhile, Lake Syrytkul is more responsive to climate aridization because of its limnological characteristics and less precipitation in the piedmont area. Climate events were the main drivers for lake ecosystems dynamics throughout almost the whole history of the lakes. The records of lake sediments reflect several climate events noted elsewhere in the Northern Hemisphere: Lateglacial–Holocene transition (~12,000–11,600), Preboreal oscillation (~11,200–11,000 cal. BP), climate warming and aridization (~9700–9600 cal. BP), warming and increase in precipitation since 9000 cal. BP, climate aridization at ~5800 cal. BP, cooling since 4000 cal. BP, and warming at ~2500 cal. BP. Climate warming of the last hundred years was not reflected in lake sediment records because of the significant human impact on the lake ecosystem. The upper sediments of both lakes are enriched in As, Bi, Sb, Te, Sn, Cd, Cu, Zn and Pb because of the influence of the Karabash copper smelter. However, the significant changes of the Lake Syrytkul ecosystem are not related to the technogenic impact and explained mainly by the dam construction. The changes in diatom communities identified in Lake Ufimskoe, which is located in an area geologically sensitive to acidification, are related to the acidification and heavy metal loading on the water area.

The discovery and archaeological exploration of three Mesolithic sites in the Adige Valley between 1968 and 1975 has allowed the identification of the Sauveterrian and Castelnovian complexes south of the Alpine watershed and enabled the definition of a chrono-stratigraphic sequence of reference for North-eastern Italy spanning from the Preboreal to the first part of the Atlantic. Together with several other findings in the Dolomites, these discoveries led to the development of a model of seasonal migration of the Mesolithic groups settled in the Adige River Basin from the valley-bottom to the Alpine medium-to-high mountain territories.