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The impact of postglacial palaeoenvironmental changes on the properties of sediments in the kettle hole at Jurki (NE Poland)

Karasiewicz T. M., Hulisz P., Noryśkiewicz A. M., Stachowicz-Rybka R., Michalski A., Dąbrowski M., Gamrat W. W.

Geological Quarterly

2017

Vol. 61, No. 2

319--333

This research is focused on a small kettle hole located within the Morąg moraines (Iława Lake District, NE Poland). The study objective was to determine the impact of palaeoenvironmental changes in sedimentation and properties of sediments filling the bottom of the kettle hole. Sedimentological, geochemical, and palaeobotanical studies enabled us to distinguish several development phases of the kettle hole, and cluster analysis performed on physicochemical data yielded seven local geochemical zones (JuI/I to JuI/VII). The beginning of biogenic sedimentation in the conditions of a small water body, functioning in the Late Glacial period (4.20–4.10 m), was determined on the basis of palaeobotanical research. Sediments deposited in the lake during its further evolution were rich in microelements such as Ca, Na, Mg, and K, and to a smaller extent – Fe and Mn (JuI/I–III local geochemical zones). The Late Glacial lacustrine period ended with the accumulation of very silty, pollen-free gyttja, with a stratigraphic hiatus (JuI/IV, 3.40–3.20 m). The sediments were enriched with SiO2ter, which indicates an increased rate of slope erosion, and concretions of Fe-Mn occurring below this layer (JuIII) provide evidence for lowering of the water level and even desiccation. In the Holocene, the lacustrine period ended with the accumulation of coarse detrital gyttja (3.20–2.60 m). Palaeobotanical data indicate that the next group of sediments were deposited in the Late Subboreal and Subatlantic periods (2.60–0.0 cm, JuI/V–VII; sedge peat). Their properties were varied and related to hydrologic conditions, limited denudation, and vegetation succession. There was also a significant change in the trophic conditions of the water and consequently in the sediments of the kettle hole, which changed during the lacustrine period from basic to acid, and strongly acid in the surface layer. This reaction may be related to a change in the water regime as well as to human impact in the environment, which led to the colonization of the peat bog by Sphagnum moss.

Charakterystyka środowisk depozycyjnych Jeziora Czechowskiego i jego otoczenia

Kordowski J., Błaszkiewicz M., Kramkowski M., Słowiński M., Tyszkowski S., Brauer A., Brykała D., Gierszewski P., Lamparski P., Lutyńska M., Mirosław-Grabowska J., Noryśkiewicz A.M., Obremska M., Ott F., Wulff S., Zawiska I.

Landform Analysis

2013

Vol. 25

55--75

W artykule przedstawiono przegląd badań nad morfogenezą misy jeziornej Jeziora Czechowskiego na Pojezierzu Starogardzkim. W dostępnych odsłonięciach, wkopach i wierceniach o nienaruszonej strukturze przeprowadzono analizę sedymentologiczną osadów glacjofluwialnych, glacjolimnicznych, limnicznych i stokowych. Wyniki tej analizy uzupełniono rezultatami kartowania geologicznego i geomorfologicznego. W efekcie przeprowadzonych prac stwierdzono, że misa jeziora założona jest w głębokiej rynnie subglacjalnej, która do początku allerødu zakonserwowana była bryłami martwego lodu. Ich wytopienie doprowadziło do powstania zróżnicowanej morfologii dna rynny. W najgłębszych miejscach, dzięki ograniczonej miksji, były warunki do zachowania rocznej laminacji osadów dennych. Sedymentacja osadów glacjofluwialnych w otoczeniu rynny była bardzo zróżnicowana i w wielu miejscach wskazuje na warunki przepływu nadkrytycznego. W przypowierzchniowej warstwie osadów sandrowych stwierdzono ślady zapisu procesów mrozowych (gleby mrozowe) oraz wytrącenia węglanowe wskazujące na występowanie warunków peryglacjalnych po zaprzestaniu przepływu proglacjalnego. Osady limniczne są również zróżnicowane w zależności od cech morfometrycznych basenu sedymentacyjnego, a przede wszystkim od głębokości ich depozycji. Osady stokowe pochodzą w większości z ostatnich dwustu lat, a ich depozycja nastąpiła wskutek działalności gospodarczej człowieka.

The paper aims to review the investigations on the genesis of the Czechowskie Lake basin (Starogard Lakeland, north-central Poland). The sedimentological analysis of the glaciofluvial, glaciolimnic, limnic and colluvial deposits have been conducted in the outcrops, pits and boreholes with undisturbed cores. They were supplemented by the results of the geological and geomorphological mapping. Summing up the investigations it can be stated that the lake basin developed within a deep subglacial channel which was preserved by the dead ice blocks till the onset of the Allerød. Their melting led to the emergence of a morphologically diversified lake basin. The conditions in its deepest parts, due to hampered mixing and wave action, favoured the preservation of the annually laminated sediments. The glaciofluvial deposition in the vicinity of the lake was diverse and in many places it indicates the supercritical condition of the water flow. Within the near-surface layer of outwash deposits were recognized the traces of the periglacial processes and calcareous precipitates which indicate short glaciolimnic periods or breaks in sedimentation. The limnic sediments are also diversified and dependent on the morphometric features of the sedimentary basin, mostly the depth of the deposition. Colluvial deposits have originated mostly in the last 200 years as a consequence of the transient deforestation of the surrounding area.

History of the Białowieża Primeval Forest, NE Poland

Milecka K., Noryśkiewicz A.M., Kowalewski G.

Studia Quaternaria

2009

Vol. 26

25-39

Białowieża in Poland is a very famous region in Europe (because of its primeval forest and bison population), but its environmental history is poorly known. This article shows the results of palynological analysis, macrofossil analysis and geological settings of two mires in the Białowieża Forest. The pollen diagrams show changes of the vegetation cover from the younger part of the Late Glacial until the present time. The relative time scale is based on palynostratigraphy and comparison to published results of other sites from the adjacent regions. During the Late Glacial two stages of the vegetation succession were revealed: steppe and forest during the Alleröd period and tundra-like vegetation during the Younger Dryas. The Holocene history consists of five stages of plant cover development. The special features of the Białowieża Forest are conditioned by two main factors: low degree of anthropogenic impact and influences of continental climate and boreal zone, stronger than in the other regions of Poland.