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• Vegetation changes in NE Poland were reconstructed. • Pollen percentage revealed similar trends as curve of δ18O NGRIP. • The onset of the GS-1 is diachronic in the record of Cladocera percentages and pollen percentages. • The pollen record of the GI-1b cold spell revealed the Gerzensee oscillation. By applying pollen and subfossil Cladocera analyses to the Late-Weichselian section of the sediment profile from Lake Suchar Wielki, we aimed to track paleoenvironmental changes in NE Poland, locally (lake formation and its early development) and regionally (terrestrial plant succession). The article aims to indicate how not only stadial-interstadial changes were noticeable in the study area, but above all even short-term climatic fluctuations. The obtained record covers the period of ca. 13,400–11,500 cal. BP, i.e. the part of the Allerød interstadial (GI-1c1 to GI-1a), the Younger Dryas stadial (GS-1), and the very beginning of the Holocene. During the Allerød, a short-lasting cooling was recognized (the Gerzensee oscillation, GI-1b). It is the first study for this part of Poland evidencing the inter-Allerød cooling by the Cladocera-based mean July temperature reconstruction. In the palynological record it was reflected in an increased temporary share of Betula alba t. pollen, while in the Cladocera record in the appearance of cold-water taxa and low total abundance. At the transition to the Younger Dryas further cooling took place that was evidenced by the increase in the proportion of herbaceous plants together with a distinct decrease of tree pollen concentration in sediments as well as by important changes in Cladocera communities including reduced species diversity, disappearance of more demanding temperate taxa and the expansion of cold-tolerant species. The palaeobotanical record revealed that the proportion of juniper pollen in the studied area was lower than in other regions of NE Poland. A case study demonstrated this was mainly due to local conditions. Moreover, it is noteworthy that, at the end of the Younger Dryas, spruce appeared temporarily in local forest stands. The results of the study suggest climate change, which has also been recorded in ice cores from Greenland as cooling ca. 11,800–11,600 cal. BP. [ABSTRACT FROM AUTHOR]

Abstract Kettle holes are a circular-shape product of ice decay, and thus are strongly linked with young glacial landscapes. Once glaciation terminates, these holes transform either into wetland and lakes or occasionally into kettle-hole mires. Since an entire sediment sequence preserve in the kettle-holes, these provide an excellent settings to exploit any sensitive paleoenvironmental changes. Here, the kettle-hole mire located onto the Brda River outwash plain (Tuchola Forest) is explored towards a better understanding of local and global environmental trends in the Late Glacial – present day time frame. To fulfill this, multi-proxy study as geochemical, palynological and macrofossils analyses along with the radiocarbon dating are used. Therefore, this study allows to distinguish five phases of steep environmental gradients in the investigated mire, as follows: (1) paludification after glaciation, when dead-ice melted and long-term permafrost was degraded, (2) lake started to disappear in the Late Glacial, followed by a rich vegetation in the first part of the Holocene, (3) vegetation encroachment onto the lake in the first part of the Holocene, which consequently turned into an peat bog, (4) the late Holocene peat bog with a limited human influence, and finally (5) the peat bog with a major human impact along with acidification as related to sandy underlying sediments, leaching of calcium carbonate, recharge from precipitation and pine monoculture. As additionally apparent from this small ecosystem, both local (character of substrate sediments, morphology of the area, rate of permafrost melting, climate conditions and human activity) and regional (climate changes and human activity) are detectable. Nevertheless, the record of these changes is sometimes unclear. Highlights • Multi-proxy study of biogenic kettle-hole sediment in North Central Poland. • Kettle-hole developed in five phases in the Late Glacial – the Holocene time frame. • Record of vegetational and chemical changes in the kettle-hole sediments • Intensive erosion along with acidification took place. • A greater human impact at the end of the Atlantic [ABSTRACT FROM AUTHOR]

Loess deposits have been described in the past for the upper section of Buca Dei Corvi succession (Central Italy). In this paper the deposits were re-analysed to clarify the depositional environment and to attempt a paleoclimate reconstruction. Two radiocarbon dates on pedogenic carbonate constrain the ages to the Late Glacial, and are consistent with previous OSL dating of the top of the succession. The non-marine mollusc assemblage shows typical character of cold and dry climatic conditions, testified by strong oligotypical composition. Mineralogy and geochemistry of the sediments indicate the abundant presence of exotic quartz mineral which can be explained only by wind transport. Probably, wind transport was also responsible of deposition of carbonate which then dissolved and re-precipitated producing pedogenic concretions. Stable isotopes ( 13 C/ 12 C and 18 O/ 16 O ratios) of the concretions are consistent with a climate drier than present conditions, with an environment characterized by sparse vegetation. [ABSTRACT FROM AUTHOR]

In this study we investigate how climate fluctuation in the Late Glacial period influenced the development of a lake and its catchment located in the East European Plain. We analyzed the sediments of the lake for pollen, subfossil Cladocera, macrofossils and chemical composition. We aimed at disentangling: (1) the climate changes and their limno-ecological responses, (2) temperature dynamics with the use of Cladocera-based transfer function (MJT) and macrofossil-based reconstruction of mean minimum July temperature (MMJT), (3) timing of the response of different proxies to environmental changes. The results of multiproxy analyses explicitly suggest that the main driver for changes in aquatic and terrestrial ecosystems as well as geomorphological processes in the catchment was climate. Reconstructed temperatures generally follow the known trends showing the increase at the beginning of the Allerød and decrease at the beginning of the Younger Dryas. However, there are some discrepancies between the two reconstructions as well as between the generally accepted temperature trends in Late Glacial. The timing of the proxy response to climate change differs, the aquatic proxies responding first. [ABSTRACT FROM AUTHOR]

• July temp. dropped at the YD onset, then increased up to the Holocene onset. • There were four cold and four warm summer temp. oscillations during YD. • Seasonal contrast was higher at the AL/YD and YD/Hol. transitions than in mid-YD. • Water level fluctuations, TP content and winds also drove lake biota in the lake. • Lake ecosystem transition from the YD to Holocene took place in four stages. The Younger Dryas (YD) is a roughly 1,100-year cold period marking the end of the last glaciation. Climate modelling for northern Europe indicates high summer temperatures and strong continentality. In eastern Europe, the scale of temperature variation and its influence on ecosystems is weakly recognised. Here, we present a multi-proxy reconstruction of YD conditions from Lake Gościąż (central Poland). The decadal-resolution analysis of its annually varved sediments indicates an initial decrease in Chironomidae-inferred mean July air temperature followed by steady warming. The pollen-inferred winter-to-summer temperature amplitude and annual precipitation is highest at the Allerød/YD transition and the early YD (ca. 12.7–12.4 ky cal BP) and YD/Holocene (11.7–11.4 ka cal BP) transition. Temperature and precipitation were the main reasons for lake level fluctuations as reflected in the planktonic/littoral Cladocera ratio. The lake's diatom-inferred total phosphorus decreased with increasing summer temperature from about mid YD. Windy conditions in the early YD until ∼12.3 ka cal BP caused water mixing and a short-lived/temporary increase in nutrient availability for phytoplankton. The Chironomidae-inferred summer temperature and pollen inferred summer temperature, winter temperature and annual precipitation herein are one of only a few in eastern Europe conducted with such high resolution. [ABSTRACT FROM AUTHOR]

In order to evaluate the potential of the Schmidt hammer for relative age dating of Late Pleistocene moraines and rock glaciers, rebound (R) values were collected at 38 sites in two formerly glaciated valleys in the Western Tatras in northern Slovakia. A large statistical population of measurements obtained from moraine and rock glacier surfaces was used to analyze the variability of mean R-values in the same lithology and overall southern valley exposition. Four separate sets of glacial/periglacial morphosystems are present at different positions in the Western Tatras starting from valley outlets to the highest cirques, which represent successive phases of deglaciation. R-value means and 95% confidence intervals for selected Last Glacial Maximum (LGM), and Late Glacial (LG-1, LG-2 and LG-3) stages (respectively, 40.1±1.1, 46±0.5, 53.5±1.0 and 60.5±0.3) are significantly statistically different and values for each age category are comparable for the two analyzed valleys. The results of weathering indexes used in conjunction with geomorphological relationships were taken together to reconstruct the pattern of deglaciation on southern Tatra slopes. It is stated that the Schmidt hammer technique may be successfully used as a relative age dating tool for Late Pleistocene glacial and periglacial deposits, and with this method, it is possible to differentiate between Late Glacial moraines and rock glacier systems of different age. [ABSTRACT FROM AUTHOR]

• Atmospheric and climate teleconnections are found to have impacted West Spain. • Atlantic Cl aerosols impacted at ~10.9–10.2 ka and from ~2.8 ka until the present. • Asian/Saharan ash/dust influxes impacted at ~13.8–12.8 ka and ~7.9–3.2 ka. • Southcentral Spain volcanic ashes impacted North Iberia at ~6.8–5.8 ka. • Frequent dust events and low oceanic influx enhances fire activity at ~8.2–2.8 ka. The Iberian Central System (ICS) is a clue region to reveal Mediterranean/Atlantic inferences over Iberia. We present a multidisciplinary study from western Spain conducted in the Navamuño depression (ND), covering the last 16.8 ka (cal BP). A reconstruction of the palaeotemperature from the resulting geochemical data highlights four cold and dry intervals, namely, the Oldest Dryas, Older Dryas, Intra-Allerød Cold Period (IACP), and the Younger Dryas, along with warmer intervals: the Bølling (14.7–14 ka) and the Allerød (12.9–12.6 ka); however, the Greenland Interstadial GI-1c (13.4–13.1 ka) is barely distinguishable in the ND. Despite the shortage of biomass to sustain fire, the earliest charcoals are from ~14.4–13.8 ka. Evidence of ash/dust events overprinting the geochemical background starts at ~13.8–12.8 ka. Significant fire activity in the Early Holocene at ~11.7–10.6 ka affected the ND, matching the westernmost ICS data. This period includes short oceanic spells inferred from Cl peaks at ~10.9–10.2 ka and three cold intervals at 11.4, 9.3, and 8.2 ka disrupted the progressive temperature increase. The Mid-Holocene showed a continuously increasing trend towards an arid climate, peaking at 4.2 ka under a pervasive dust influx from North Africa, which has prevailed since almost ~7.9 ka. A prominent volcanic event at ~6.8–5.8 ka is in Navamuño and Roñanzas (Asturias, N Spain; Gallego et al., 2013) identified from heavy metal-rich layer, synchronous with the last known eruption of the Calatrava volcanic field (South-Central Spain; Poblete-Piedrabuena et al., 2019). This volcanic eruption could affect many other regions half north of Iberia. The pervasive presence of oceanic aerosols in the last three millennia (2.8 ka ~) allowed the formation of a Cl-rich peat layer during the Ibero-Roman humid period ~2.1 ka, before a changing around ~0.4 ka toward colder and drier conditions at the Little Ice Age (LIA) period. [ABSTRACT FROM AUTHOR]

Abstract: Morphological, geological, geochronological and palynological analyses show that the landscape, climate and hydrological history of the Seim River basin includes: 1) a period of sandy Terrace 1 formation by shallow flows, with the surface transformation by cryogenic and aeolian processes, close to the Last Glaciation Maximum; 2) a cold and dry period about 16–14K radiocarbon years B.P. with very high surface runoff and extremely large meandering channel formation; 3) a period between the Oldest Dryas and the Preboreal of non-steady surface runoff decrease, large meander abandonment, and formation of smaller channels against the background of climate warming; 4) a period of relative stability of hydrological regime and small variations of water runoff as in modern rivers—throughout the Holocene. [Copyright &y& Elsevier]

The paper deals with the relationship between the temporal occurrence of landslides and climatic changes in the Italian Dolomites since the Late glacial. After an introduction on the state of the art, with particular reference to the Alpine region, the results of recent investigations in the two study sites are illustrated. At Cortina d''Ampezzo, several landslides were dated mainly by the radiocarbon method. The most ancient landslide event there involved large rock slides, which affected the dolomitic slopes following the withdrawal of glaciers after the Last Glacial Maximum (LGM), and also slides and flows mainly occurring in pelitic materials of the valley floors (from 13,000 to 10,000 cal BP). A later series of flows occurred between 5500 and 2500 cal BP. In the Upper Badia Valley (Alta Badia), the most ancient events go back to 10,000 and 9000 cal BP, and correspond with earth flows that followed vast rotational slides affecting the bedrock up to a depth of about 50 m. More recent earth flows, involving more modest amounts of material, took place between 6500 and 2300 cal BP.By analysing the dates from the two study areas, it was possible to correlate the recorded increase of landslide activity with the climatic changes occurring at the boundary between the Late glacial and the Holocene and between the Atlantic and the Subboreal, and to compare the results with those derived from other European regions. The types and causes of landslides taking place in these two periods were substantially different, reflecting the different morphoclimatic conditions that existed in the two areas when these mass movements were triggered. Finally, notwithstanding the importance of non-climatic causes, such as geological–structural factors and possible human influences, it is concluded that many of the dated landslides can be considered as indicators of climatic change. [Copyright &y& Elsevier]

This paper presents the preliminary results of the geoarchaeological study of Abric de la Cativera (el Catllar, Tarragona), a rock-shelter containing late glacial and early Holocene stratification spanning between c. 11.3 and 7.9 ka 14C BP.The site is located in the Gaia` River Valley, on the southern Catalonian coast. The shelter, situated at the foot of a low limestone wall, was discovered in 1994. Preliminary fieldwork was performed in 1995, comprising excavation of the early Holocene layers and the sampling of the stratigraphic succession.The geoarchaeological study was undertaken using a descriptive approach and so far has included a geomorphological survey of the surroundings, the stratigraphic study of the site and micromorphological analysis. High priority goals are a diachronic reconstruction of environmental change at the Pleistocene–Holocene boundary and an understanding of the relationships between anthropic and non-anthropic dynamics, paying special attention to site formation processes.The site's archaeological record represents human occupations affiliated to the microlaminar Epipalaeolithic (complex C and unit B) and to early Holocene macrolithic technocomplexes (unit A), according to the lithic assemblages recovered. Artefacts, by-products, ecofacts, manuports and art objects were collected during excavations and archaeological features were detected.The results of the micromorphological study show that the abrupt climate changes around the Pleistocene–Holocene (PH) limit are well recognisable at the site. The beginning of the Younger Dryas (YD) and the PH limit are both represented by erosional surfaces and by the inwash of slope sediments cutting the late glacial pre-YD alluvial succession deposited by the Gaia` River. The shift from alluvial to a gravity-driven sedimentary system is the result of an overall modification of the valley's morphodynamics. The early Holocene units record the transition to a Mediterranean environment and the stabilisation of the slope.Human inputs are abundant in the entire stratigraphic succession, except in the YD layers, where a sudden decrease is observed. Anthropic activities determined the accumulation and modification of various components and the formation of anthropogenic microfacies and features. The observation of micromorphological samples from layer A, which contains occasional potsherds, suggests its in situ position, which is in contrast with the existing models on the regional processes of neolithisation.A comparison between the pedo-sedimentary and archaeological records indicates that the timing of environmental and cultural change at Abric de la Cativera is differential, suggesting that the latter results from behavioural and cultural dynamics, rather from environmental factors. [Copyright &y& Elsevier]

• Section in Zaraysk records human occupation from Late Palaolithic till Medieval. • Paleosol within the Paleolithic layer has signs of humification and faunal activity. • Cryogenic features and eolian sedimentation point to cooling during Younger Dryas. • Luvisol indicates persistence of forest on site during major part of the Holocene. • Chernozemic relicts in the Luvisol point to a short stage of steppe vegetation. Paleosol-sedimentary sequences encountered in the settlements with long occupation history could provide a unique insight into the trends of landscape development and human-environment interaction over long time scales. We studied paleosols exposed by the excavations in the Kremlin of Zaraysk (Central European Russia) which were formed during the late Pleistocene and the Holocene and contain archaeological materials spanning from Upper Palaeolithic till late Medieval. Archaeological findings and numerous radiocarbon dates provide a reliable time frame for paleopedological record which we extracted from paleosols using macro- and micromorphological observations as well as physical and chemical properties and paleobotanical indicators (phytolith assemblages). The basal layer without archaeological materials presents signs of soil formation which resemble Bryansk fossil soil developed in the second half of Marine Isotope Stage (MIS) 3. The overlying archaeological stratum - one of the Gravettian cultural layers is linked to the paleosol level known as Zaraysk soil. Its age is estimated at 16 ka BP. Macro- and micromorphological features point to moderate dark humus accumulation, anthropogenic compaction and cryogenic processes at the final stages of paleopedogenesis. Poorly sorted heterogeneous composition of the mineral material with a large proportion of sand grains indicates colluvial origin of the paleosol parent material. The overlying sorted silty deposit supposes contribution of windblown material to its formation. We associate cryogenic and eolian processes at the end and after Zaraysk soil development with the cold intervals at the end MIS 2, presumably with the Oldest and Younger Dryas. The complete profile of Luvisol/Grey Forest Soil with eluvial and illuvial horizons and relict dark humus morphons is developed within the silty unit. This soil indicates long-term natural pedogenesis under first steppe and then deciduous forest vegetation during major part of the Holocene. The topsoil however is formed by clear plough horizon which points to cultivation started in the Middle Ages. Sharp boundary separates the buried Luvisol from the overlying cultural layer-Technosol developed after building of Zaraysk Kremlin in the 16th century. Technosol presents a mixture of natural soil with construction materials, especially limestone fragments. Soil units, both natural and affected by humans, are not separated one from another by an unaltered C horizon, so soil-forming processes from the upper soils penetrate into the underlying ones forming a multistory pedocomplex. [ABSTRACT FROM AUTHOR]

• Long core was investigated in terms of ostracods, pollen and stable isotopes. • Cyprideis torosa was dominant during the late glacial in the brackish conditions. • There is a transition from oligotrophic to eutrophic conditions at the end of YD. • Relatively wet and dry phases have been observed through the core. • Older Dryas, Allerød interstadial, and Younger Dryas can be discernable in core. This study investigates the ostracod assemblages obtained from a sediment core from a paleolake in the Sağlık plain in south-central Anatolia (Turkey). In addition to ostracods, oxygen and carbon stable isotopes of ostracod shells were analysed and pollen analysis of the core undertaken. The sediments comprise the Late Glacial and early Holocene interval with an approximate 14C age from 18,000 to 6700 14C years ago, after applying a correction for reservoir effects. Eight podocopid ostracod species were recorded, among them Cyprideis torosa and Candona sp. which were used for stable oxygen and carbon isotope analyses. C. torosa dominated during the Late Glacial while Candona sp. dominated most of the early Holocene assemblages. Both forms of C. torosa disappear abruptly close to the onset of the Holocene. Around this time, ostracod preservation was dominated by many black coloured valves and carapaces. Based on ostracod assemblage data and isotope analyses, relatively wet phases were identified for the Older Dryas, Younger Dryas, and during the mid-Holocene at around 7500 14C years ago. Relatively dry phases were identified during the Allerød interstadial, at the end of YD, and at about 6700 14C years ago. An oligotrophic and brackish lake persisted until shortly before the end of the YD, when, according to the δ 13C values, conditions gradually became more eutrophic. The sudden disappearance of C. torosa at the end of the YD seems the consequence of anoxic bottom water conditions and/or eutrophication. Alternating wet and dry phases characterize the early Holocene, with a longer period of wet and oligotrophic conditions around 7500 14C years ago (ca. 8300 calBP). Ostracod assemblages and isotope records indicate a dry and more productive lake around 6700 14C years ago (ca. 7550 calBP). [ABSTRACT FROM AUTHOR]

Qinghai Lake is the largest lake on the Tibetan Plateau (TP), located between the extremely arid Qaidam Basin to the west and the severely desertified Gonghe Basin to the south. Extensive aeolian sediment at Qinghai Lake is ideal material to reconstruct regional aeolian activity, and to better understand the relationship between desertification and climatic change in the lake basin. Aeolian sand accumulation is usually accompanied by erosion, hence, depositional hiatuses and disconformities must be identified for reliable reconstruction of regional aeolian activity. To date, the low density of age sampling around Qinghai Lake has hindered identification of hiatuses. In this study we report the first high density OSL dating; 41 OSL ages were obtained from two aeolian sand sections, Dongwei (DW) and Niaodao (ND). Sand accumulation trends recorded in the high-density OSL sampling sections were consistent with previously published probability density function (PDF) ages for the northeast TP. The middle Holocene (~7 to ~4 ka) was characterized by very low accumulation rates, with rapid sedimentation in the Late Glacial to Early Holocene (~14 to ~7 ka) and the Late Holocene (after ~4 ka). A ~3 ka hiatus in accumulation between ~7 to ~4 ka was identified in the DW section, but the ND section showed successive accumulation since the Late Glacial (~14 ka), on sub-orbital and millennial scales. Our environmental reconstructions are consistent with previously published aeolian data and paleoshorelines records. The combined evidence shows: strong aeolian activity since ~14 ka to ~9 ka; initiation of pedogenesis at ~9 to 7 ka; intensified soil development between ~7 ka and ~4 ka (with the most intense pedogenesis and least aeolian activity between ~6 to ~4 ka); relatively weak paleosol formation from ~4 to ~2 ka; and renewed aeolian activity after ~2 ka. • First use of high-density OSL dating of aeolian sediments at Qinghai Lake • Strongest aeolian activity was in the Late Glacial to Early Holocene (~14–9 ka). • Lowest aeolian activity and strongest pedogenesis occurred between ~7–4 ka. • Pedogenesis weakened between ~4 to ~2 ka and aeolian activity renewed after ~2 ka. • Aeolian and paleoshoreline evidence is consistent in the Holocene. [ABSTRACT FROM AUTHOR]