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Instability of the environment at the end of the Eemian Interglacial as illustrated by the isopollen maps for Poland

Kupryjanowicz M., Granoszewski W., Nalepka D., Pidek I. A., Walanus A., Balwierz Z., Fiłoc M., Kołaczek P., Majecka A., Malkiewicz M., Nita M., Noryśkiewicz B., Winter H.

Geological Quarterly

2016

Vol. 60, No. 1

225--237

Many terrestrial pollen profiles from Poland (and a few pollen records from other parts of Central Europe) show the end of the last interglacial (Eemian, MIS 5e) to have been characterized by climatic and environmental instability. This is expressed by a strong, rapid cooling in the middle part of the pine phase ending this interglacial (E7 regional pollen assemblage zone), and then a re-warming at the very end of this phase, immediately before the transition to the glacial conditions of the last glaciation (Vistulian, Weichselian, MIS 5d). We have characterized the regional distribution of these climatic fluctuations in Poland on the basis of isopollen maps prepared for the Eemian Interglacial based on palynological data from 31 Polish pollen profiles. These maps show unequivocally that the intra-interglacial cooling at the end of the Eemian Interglacial was a transregional phenomenon, which was reflected very clearly by a temporary openness of vegetation across the whole of Poland. It was associated with a distinct decrease in pine forest areas and an increase in birch forests and open communities of cold steppe type with a domination of Artemisia. The pronounced climate and environment instability during the last phase of the Eemian Interglacial may be consistent with it being a natural phenomenon, characteristic of transitional stages. Taking into consideration the currently observed global warming, coinciding with a natural cooling trend, the study of such transitional stages is important for understanding the underlying processes of climate change.

Non-pollen palynomorphs characteristic for the dystrophic stage of humic lakes in the Wigry National Park, NE Poland

Fiłoc M., Kupryjanowicz M.

Studia Quaternaria

2015

Vol. 32, Nr 1

31--41

The numerous dystrophic (humic) lakes are a very important feature of Wigry National Park, NE Poland. As the most recent palaeoecological data indicate, at the beginning of its development (in the Late Glacial and Early and Middle Holocene) these water bodies functioned as harmonious lakes, and their transformation into dystrophic lakes and the stabilization of the trophic state took place at the beginning of the Subboreal. Palynological analysis of sediments from two such lakes (Lake Ślepe and Lake Suchar II), with special emphasis on non-pollen palynomorphs (NPPs), was aimed at a detailed biological characterization of dystrophic lakes during their long-lasting existence. The obtained results allowed for the designation of organisms characteristic for dystrophic lakes, of which representatives appeared with the decreasing pH of the water and the formation of Sphagnum peat around lakes. These organisms were divided into four groups: algae, fungi, testate amoebas, and animals. Their representatives appear in various developmental stages of dystrophic lakes.

Late Glacial and Holocene vegetation changes in the Wigry National Park, NE Poland - new pollen data from three small dystrophic lakes

Fiłoc M, Kupryjanowicz M., Drzymulska D

Studia Quaternaria

2014

Vol. 31, Nr 1

5--16

The main phases of the Late Glacial and Holocene development of vegetation in the Wigry National Park were reconstructed based on the pollen analysis of sediments from three small dystrophic lakes (Lake Suchar Wielki, Lake Suchar II and Lake Slepe). At the current stage of research, the age of the studied deposits was determined by AMS radiocarbon dating of few samples only. This meant that the chronology of the investigated profiles had to be estimated also indirectly using their palynological correlation with a radiometrically well-dated profile from Lake Wigry. The obtained pollen data confirmed the picture of the postglacial vegetation changes of the Wigry National Park, which was based on earlier studies of Lake Wigry. Furthermore, it documented the existence, mainly in the Preboreal and Atlantic chronozones, of temporary changes in vegetation, which might be a reaction to a short-lived cold fluctuations of climate.