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EN
The stratigraphy of Late Pleniglacial and Late Glacial fluvio-to-aeolian succession was investigated in two sites located at the Niemodlin Plateau, SW Poland. Lithofacial analysis was used for the reconstruction of sedimentary environments. An absolute chronology for climatic change and the resulting environmental changes were determined based on optically stimulated luminescence (OSL – nine samples) and radiocarbon (three samples) dating methods. Four phases of changes in sedimentary environments were established. The first depositional phase correlates with the Last Permafrost Maximum (24−17 ka) based on the type and size of the periglacial structures, which aggraded under continuous permafrost conditions. During 17.5−15.5 ka (upper Late Pleniglacial), a stratigraphic gap was detected, owing to a break in the deposition on the interfluve area. The second depositional phase took place during 15.5−13.5 ka. During this phase, the first part of the dune formation (Przechód site) and fluvio-aeolian cover (Siedliska site) was deposited. The sedimentary processes continued throughout the entire Bølling interstadial and Older Dryas. In the third phase (Allerød interstadial), soil formation took place. At the Siedliska site, palaeosol represented Usselo soil type, whereas at the Przechód site, there was a colluvial type of soil. The last phase (Younger Dryas) is represented by the main phase of dune formation in both sites. After the Younger Dryas, no aeolian activity was detected. High compliance with both absolute dating methods was noticed.
2
Content available remote A Tree-Ring chronology from Allerød–YD transition from Koźmin (Central Poland)
EN
Subfossil trunks of pine (Pinus sylvestris L.) from the Late Weichselian were discovered in the site Koźmin in the Koło Basin, central Poland (Dzieduszyńska et al., 2014a). Another part of organic sediments with trunks was excavated in the frame of the research project. Altogether 224 samples from Koźmin were analysed dendrochronologically; they represented generally young trees, 40 to 70 years old. Based on the most convergent sequences, the chronology 2KOL_A1 was produced, 210 years in length. With the wiggle-matching method, it was dated to ca. 13065–12855 cal BP. Dendrochronological dating of trunks buried in organic sediments, most of which occurred in situ, revealed that tree deaths occurred successively, over more than 100 years. That could have been due to unfavourable climatic conditions, as well as extreme events, e.g. strong winds.
EN
This paper presents the Late Glacial stage of the development of the Białe Ługi peatland in the southern Holy Cross Mountains, based on a comprehensive palaeoenvironmental data. A complex analysis of palynology, Cladocera, sedimentology, geochemistry and 14C dating were used. Organic deposition was initiated during the Oldest Dryas. The sedimentary record of the aquatic and terrestrial ecosystems reflects considerable difference between cooler (Oldest, Older and Younger Dryas) and warmer phases (Bølling and Allerød). Periods of intensified interaction between Aeolian processes and peatland are related to stages of disappearing vegetation and changes in aquatic invertebrate communities. We therefore suggest that peatlands were created as a result of local lithological-structural, tectonic, hydrogeological and morphological conditions, and the peatland development rate was largely influenced by changing climatic conditions, which determined local vegetation development, intensity of denudation processes and water level changes. The results validate significance of selection and use of several methods, as well as value of biogenic deposits from the Białe Ługi peatland as archives of past climate change in the Małopolska Upland. Relatively stable water conditions and uninterrupted biogenic sedimentation in the Late Glacial that were provided by the geological structure and relief suggest the studied peatland is a leading one in the region.
EN
We reconstruct palaeoenvironmental changes since the Late Holocene in the Orava-Nowy Targ Basin, with an emphasis on anthropogenic influence (Walker et al., 2018). This reconstruction employs multiproxy analyses of the Otrębowskie Brzegi poor fen. We combined radiocarbon and 210Pb dating with elemental geochemistry, stable lead isotopes, and palaeobotanical analyses. The core we investigated covers a period from 4200 ± 100 BC to the present, with a peat accumulation rate varying between 0.001 and 0.243 cm y-1. Heavy metal concentrations, Pb isotopic ratios, and a palynological analysis revealed a significant impact of human activities in the past. The highest concentration and accumulation rate of Pb, were found around 1950 AD. The 206Pb/207Pb quotient ranged between 1.168 and 1.223, with average value around 1.198. Most of the interpretation was based on Pb and its stable isotopes; however, other elements were also important indicators of natural and anthropogenic environmental changes. Our results revealed similarities between the geochemical composition of the peatland studied and other peatlands from the Orava-Nowy Targ Basin.
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