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Younger Dryas climatic reconstructions in central Poland

Pawłowski D.

Acta Geologica Polonica

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2017

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Vol. 67, no. 4

567--584

EN

Cladoceran-based paleotemperature estimates for the Younger Dryas for ten sections of paleo-oxbow lakes, valley mires, and lacustrine sediments from central Poland are presented, and their potential usefulness to climatostratigraphy is described. Most of the changes observed in the cladoceran assemblages are responses to climate changes. The cladoceran-based temperature reconstructions reflect cold conditions during the Younger Dryas (YD) and allow a division of this period into two phases: an older colder phase, between 12,800 and 12,000 cal yrs BP, and a younger, warmer phase, between ca. 12,000 and 11,500 cal yrs BP. The geomorphological features of the study sites and local environmental forces are also taken into consideration. The cladoceran-inferred summer temperature estimates from all of the study sites correspond closely with the available climate reconstruction for the YD in central Europe.

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Optical dating and sedimentary record from the terrace depositional profile of the Warta River (Central Poland)

Dzieduszyńska D., Petera-Zganiacz J., Twardy J., Kittel P., Moska P., Adamiec G.

Geochronometria

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2014

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Vol. 41, no. 4

361--368

EN

Results of OSL dating and sedimentary studies from the profile of the low alluvial terrace of the middle Warta River are presented. The samples were dated using the single-aliquot regenera-tive method. Dating was used to establish a timing of the Weichselian Late Glacial events in the river valley environment. Stable conditions on the floodplain are expressed by the deposition of organic-rich series radiocarbon dated at 12 900-12 600 cal BP and 11 600-10 770 cal BP. Samples for OSL dating were collected from the mineral material deposited during the intensification of flood events during the Weichselian decline. The results obtained for the alluvia range from 12.78 ± 0.62 ka b2k to 14.33 ± 0.74 ka b2k. Sedimentological criteria allowed to distinguish between particular flood events. Overestimation of OSL ages is probably a result of rapidity of environmental changes in that time.

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Younger Dryas Cladocera assemblages from two valley mires in central Poland and their potential significance for climate reconstructions

Pawłowski Dominik

Geologos

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2012

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Vol. 18, No. 4

237--249

EN

Two sections of sediment from small oxbow-lake infillings located in different river valleys in central Poland were studied by cladoceran analysis in order to examine the response of aquatic ecosystems to the Younger Dryas. Lithological and geochemical records, as well as chydorid (Chydoridae) ephippia analysis were also used to reconstruct Younger Dryas climate trends. A high concentration of cladocerans, as well as the presence of Cladocera taxa preferring warmer water, was found. It is likely that local processes in the oxbow lakes were important, because the presence of warm-preferring taxa was also related to their habitats and their development. Yet local environmental forces, such as the influence of the rivers, habitat modification, macrophyte abundance, and eutrophication, were not only major factors to affect the Cladocera diversity in the Younger Dryas. The observation of changes in the composition and concentration of Cladocera in oxbow-lake infillings indicates that most of the changes occurred in response to climate changes.

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The age of the subfossil trunk horizon in deposits of the Warta river valley (central Poland) based on 14C dating

Dzieduszyńska D., Peterga-Zganiacz J., Krąpiec M.

Geochronometria

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2011

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Vol. 38, no. 4

334-340

EN

The present study focuses on investigations carried out in the Late Vistulian succession of the Warta River deposits (central Poland) in which a horizon of subfossil trees was excavated. Preliminary conclusions on time record and past environmental conditions of a forest existence determined from radiocarbon dating, pollen analyses and geological evidence appear promising with view of treering chronologies.

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Wyniki badań geologicznych i archeologicznych na stanowisku Huta Radoryska 1 (Polska południowo-wschodnia)

Żarski M., Przeździecki M., Przasnyska J.

Przegląd Geologiczny

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2006

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Vol. 54, nr 3

238-244

EN

The flint material found in 2001 on the dune surface at Huta Radoryska in South-Podlasian Lowland near Żelechów is associated with human activity. The dune is located at Mała Bystrzyca depression. This depression, filled with the Wartanian silts, Eemian, Vistulian sands and Holocene peats, was formed after dead ice had thawed during deglaciation of the Wartanian ice sheet. The dune is built from eolian sands, mainly accumulated in the Late Vistulian (the Younger Dryas). The palaeosol (podsolic), formed in the Atlantic Period, occurs in the upper part of the dune. There were flints (344) pieces within humus horizon A1 of this palaeosol and above it. Flint cores and tools were recognised among flints. Most of the artefacts were connected with the Mesolithic (the Komornica and Chojnice-Pieńki Culture). Few Late Palaeolithic and Bronze Age flint artefacts were also found. Human activity have lasted for over 10 thousand years on this dune.