New insights into lake responses to rapid climate change : the Younger Dryas in Lake Goscia(z) over dot, central Poland

The sediment profile from Lake Goscia(z) over dot in central Poland comprises a continuous, seasonally resolved and exceptionally well-preserved archive of the Younger Dryas (YD) climate variation. This provides a unique opportunity for detailed investigation of lake system responses during periods of rapid climate cooling (YD onset) and warming (YD termination). The new varve record of Lake Goscia(z) over dot presented here spans 1662 years from the late Allerod (AL) to the early Preboreal (PB). Microscopic varve counting provides an independent chronology with a YD duration of 1149+14/-22 years, which confirms previous results of 1140 +/- 40 years. We link stable oxygen isotopes and chironomid-based air temperature reconstructions with the response of various geochemical and varve microfacies proxies especially focusing on the onset and termination of the YD. Cooling at the YD onset lasted similar to 180 years, which is about a century longer than the terminal warming that was completed in similar to 70 years. During the AL/YD transition, environmental proxy data lagged the onset of cooling by similar to 90 years and revealed an increase of lake productivity and internal lake re-suspension as well as slightly higher detrital sediment input. In contrast, rapid warming and environmental changes during the YD/PB transition occurred simultaneously. However, initial changes such as declining diatom deposition and detrital input occurred already a few centuries before the rapid warming at the YD/PB transition. These environmental changes likely reflect a gradual increase in summer air temperatures already during the YD. Our data indicate complex and differing environmental responses to the major climate changes related to the YD, which involve different proxy sensitivities and threshold processes.Peer reviewe

Changes in habitat conditions in a Late Glacial fluviogenic lake in response to climatic fluctuations (Warta River valley, central Poland)

The Warta River val ley was greatly in flu enced by the ice sheet of the Last Gla cial Max i mum (LGM). A small peatland lo cated in the Warta drain age sys tem is here used as a palaeoarchive of cli ma tic and hab i tat changes dur ing the Late Gla cial (Weichselian). The ugi pound sed i ment pro file was in ves ti gated us ing multi-proxy (pol len, Chironomidae, Cladocera and geo chem is try) anal y ses that re corded changes in a fluviogenic sed i men tary de pres sion. Af ter the Poznan Phase (LGM), ugi pound func tioned as an ox bow lake that was cut off from the ac tive river chan nel as a re sult of flu vial ero sion. Since that time, the Warta River has flowed only along the sec tion now oc cu pied by the Jeziorsko Res er voir. Sed i men ta tion of lac us trine de pos its started at the be gin ning of the Late Gla cial. Sum mer tem per a ture re con struc tions in di cate cool Old est and Youn ger Dryas, but no clear cool ing in the Older Dryas. Dur ing the Youn ger Dryas the palaeolake was com pletely oc cu pied by a peatland (fen), which pe ri od i cally dried out dur ing the Ho lo cene. In ves ti ga tion of this site has tracked the re ac tion of the hab i tat to cli ma tic, hy dro log i cal and geomorphological changes through out the Late Weichselian.Peer reviewe

Multi-proxy inferred hydroclimatic conditions at Bęczkowice fen (central Poland); the influence of fluvial processes and human activity in the stone age

Fens have been forming in the river valleys of central Poland since the Bølling and went through a transformation from fully aquatic to semiterrestrial habitats during the Younger Dryas/Holocene transition. This drove plant and invertebrate communities and left a distinct pattern in chemical sediment composition, which is why river valley peatlands are sensitive palaeo-archives of climatic, hydrological and edaphic changes. Here we reconstruct the Late Weichselian history of the Bęczkowice fen in the upper Luciąża River valley using geochemical, pollen, Cladocera and Chironomidae proxies. Pollen-based age estimation indicates that the analysed peat sequence dates from the Bølling to Early Holocene. The layers 190-170 cm and 125-105 cm of the studied core were reworked by fluvial processes. Chironomidae and Cladocera communities indicate mostly limnetic conditions during the Allerød and early Younger Dryas. Peatland pools were supplied mostly by Luciąża River floods, but also by groundwater. Since the onset of the Holocene, the water level has dropped, eliminating aquatic midges and water fleas, and supporting taxa typical of astatic waters and wet soil.Peer reviewe

Environmental changes during Mesolithic-Neolithic transition in Kuyavia Lakeland, Central Poland

Funding Information: The field research was carried out as part of the project “Settlement of the Funnel Beaker Culture in the Wietrzychowice Cultural Park”, thanks to the funds of the Professor Konrad Jażdżewski Foundation for Archaeological Research and the County Labor Office - “Exploreres” program. Thanks are also due to Mrs. B. Lewandowska and Mr. A. Myrta for their invaluable help during the field works of Śmieły site, and to Kacper Świerk for his help in Chironomidae subfossils analysis. Publisher Copyright: © 2021 Elsevier Ltd and INQUAThe Wietrzychowice Cultural Park protects one of the last preserved megalithic barrows constructed by the Funnel Beaker Culture societies at the Kuyavia Lakeland (Central Poland). The nearby archaeological site at Śmieły located on the shore of Karaśnia Lake provided numerous Mesolithic and Neolithic remains such as flint artefacts, potsherds, arrowheads, and mammal bones with traces of human processing. The lake and peat sediments at the Śmieły site provided a unique opportunity to investigate man-environment relationships during the transition period from Mesolithic to Neolithic. The age-depth model for the deposits was based on five radiocarbon dates as well as archaeological artefacts. The multi-proxy study, including geochemistry, pollen, plant macrofossils, Mollusca, Cladocera and Chironomidae analyses, were conducted to recognize palaeoenvironmental changes between 7500 and 3500 BCE. Combining environmental and archaeological data, we attempt to distinguish between natural phenomena triggered by climate factors with those induced by human activity. The data indicated hydrological changes associated with natural factors: (1) the phase of aquatic ecosystem since 7500 to 5800 BCE, (2) the phase of water shallowing between 5800 and 4600 BCE, and (3) the development of alder fen in the lake shore zone since ca. 4600 BCE. Vegetation changes suggest early landscape transformations in Central Poland already due to the activity of Mesolithic societies. Fossil pollen and plant macroremains data combined with detailed map of modern soil distribution in the area allowed to identify pattern of vegetation distribution around the Mesolithic campsite. Neolithic discontinuity of habitation process between ca. 4600 and 4000 BCE (in the times of Brześć Kujawski Group of Lendyel Culture) can be associated with climate change resulting in Karaśnia Lake level lowering.Peer reviewe

Sedimentological features and depositional conditions of deposits of the accumulative fan in the Serteyka River valley (Western Russia)

Artykuł skupia się na analizie czynników klimatycznych i antropogenicznych wpływających na rozwój rozległego stożka akumulacyjnego powstałego w dolnym odcinku doliny rzeki Sertejki w zachodniej Rosji. W osadach budujących stożek rozpoznano kilka warstw osadów, tj. trzy serie deluwiów (dolna, środkowa i górna), proluwia, a także koluwia i diamikton rolny, które różnią się cechami tekstualnymi i strukturalnymi. Wykonano analizy uziarnienia i zestawiono cechy teksturalne badanych osadów stokowych: średnią średnicę ziaren, skośność, odchylenie standardowe, kurtozę. Następnie dokonano oraz omówiono relacje wybranych parametrów uziarnienia. Otrzymane wyniki wskazują na niewielką odmienność cech tekstualnych osadów budujących stożek w stosunku do materiału źródłowego. Deluwia dolne charakteryzują się bardzo słabo wykształconym laminowaniem i jasnobrunatnożółtą barwą, deluwia środkowe mają barwę brunatną, a wartości wskaźników teksturalnych są do siebie zbliżone. Znamienne dla deluwiów górnych jest subhoryzontalne warstwowanie. W tej warstwie notowane są również wahania wartości wskaźników teksturalnych. Diamikton rolny jest osadem zagęszczonym i masywnym, powstałym wskutek mieszania deluwiów górnych poprzez orkę. Wszystkie wyróżnione serie cechują się małą zawartością węglanu wapnia. Rozwój stożka rozpoczął się w trakcie pessimum Małej Epoki Lodowej wskutek zmian klimatu i zwiększenia liczby ulewnych deszczy oraz intensyfikacji antropopresji. Rozpoznano sześć zasadniczych etapów kształtowania badanej formy, które są wiązane głównie ze zmianami użytkowania terenu i wzrostem intensywności antropopresji na przestrzeni ostatnich 300 lat.The article focuses on the analysis of climatic and anthropogenic factors affecting the development of the accumulative fan in the lower sector of the Serteyka River valley in Western Russia. Within the fan deposits, several layers of sediments were identified, i.e. three units of deluvium (lower, central and upper), proluvium and also colluvium and tillage diamicton, which differ in textural and structural features. The grain size analysis was made and the textural features of the studied slope sediments were compared: mean grain diameter, skewness, standard deviation, kurtosis. Then, the relations of selected grain size parameters were interpreted. The obtained results indicate a rather small transformation of the accumulative fan in relations to the textural features of the source material. Lower deluvium is characterized by very weak lamination and light brown yellow color, the central deluvium has a brown color and the textual indicators are similar. Subhorizontal stratification is significant for the upper deluvium. This layer is characterized also by fluctuations in the value of sedimentological indices. Tillage diamicton is represented by thickened and massive sediment formed as a result of mixing of the upper deluvium by plowing. All featured series have a low content of calcium carbonate. The development of the fan began during the pessimum of the Little Ice Age due to climate change and an increase in the number of heavy rains, an also as a result of rising human impact. Six stages of the development of the studied relief form were identified, which are mainly associated with changes in land use and an increase in the intensity of anthropopression over the last 300 years

Middle Holocene Climate Oscillations Recorded in the Western Dvina Lakeland

Although extensive archeological research works have been conducted in the Serteya region in recent years, the Holocene climate history in the Western Dvina Lakeland in Western Russia is still poorly understood. The Neolithic human occupation of the Serteyka lake-river system responded to climate oscillations, resulting in the development of a pile-dwelling settlement between 5.9 and 4.2 ka cal BP. In this paper, we present the quantitative paleoclimatic reconstructions of the Northgrippian stage (8.2-4.2 ka cal BP) from the Great Serteya Palaeolake Basin. The reconstructions were created based on a multiproxy (Chironomidae, pollen and Cladocera) approach. The mean July air temperature remained at 17-20 degrees C, which is similar to the present temperature in the Smolensk Upland. The summer temperature revealed only weak oscillations during 5.9 and 4.2 ka cal BP. A more remarkable feature during those events was an increase in continentality, manifested by a lower winter temperature and lower annual precipitation. During the third, intermediate oscillation in 5.0-4.7 ka cal BP, a rise in summer temperature and stronger shifts in continental air masses were recorded. It is still unclear if the above-described climate fluctuations are linked to the North Atlantic Oscillation and can be interpreted as an indication of Bond events because only a few high-resolution paleoclimatic reconstructions from the region have been presented and these reconstructions do not demonstrate explicit oscillations in the period of 5.9 and 4.2 ka cal BP.Peer reviewe

δ¹⁸Ocarb and δ¹³Corg during the late Allerød to early Preboreal from sediment core GOS18 in Lake Gościąż, Poland

These datasets provide data for the lowest part of a new composite profile GOS18 from Lake Gościąż in central Poland. The composite profile was established using sediment cores recovered in 2015 and 2018 with an UWITEC Piston Corer at 19.6-21.5 m water depth (Bonk et al., in press). Our data covers the time interval from the onset of lacustrine sedimentation in the late Allerød to the early Preboreal. Since Lake Gościąż comprises a continuous, seasonally resolved (varved) and exceptionally well-preserved archive of the Younger Dryas (YD) climate variation, it is highly suitable for detailed investigations of lake system responses during periods of rapid climate cooling (YD onset) and warming (YD termination), respectively. Stable isotopes of oxygen in carbonates (δ18Ocarb) and of carbon in bulk organic matter (δ13Corg) were determined on bulk sediment samples contiguously taken at 0.5-1 cm resolution for the time interval from late Allerød to early Preboreal in Lake Gościąż (central Poland). All samples were freeze-dried, manually ground and homogenized, while samples for δ13Corg were additionally de-carbonized in situ. The dataset incorporates the composite depth and age [BP] for the sample midpoint, as well as the respective δ18Ocarb and δ13Corg values

Aquatic biota response to climate and habitat changes from the Valdai Glaciation to the Meghalayan (Serteya region, Western Dvina Lakeland)

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