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Molluscan assemblages in Late Holocene tufa cones in the Pieniny Mountains (southern Poland)

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Alexandrowicz W. P.

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tom Vol. 58, No. 2

269--280

EN

Limestone rock walls of various inclination form a favourable substrate for the deposition of calcareous tufas that form cone-shaped structures located at the foot of slopes or fill niches within them. Such carbonate deposits usually contain rich and diversified molluscan assemblages, whose composition and structure closely correspond to the ambient environmental conditions in the immediate vicinity. The study of the Pieniny Mountains area revealed 10 sites with such deposits. The identified malacofouna was subjected to detailed analysis. It enabled identification of three types of faunistic assemblages (Bythinella austriaca assemblage, Pyramidula pusilla assemblage, and a shade-loving species assemblage), which are related to the conditions prevailing during the deposition. Tufa cones found in the Pieniny Mountains represent the historic period (Late Holocene). The deposits provide a record of two climatic phases: warmer and colder. The former (Medieval Warm Period) involved the intensified deposition of carbonate material and the rapid growth of tufa cones. The latter – the Little Ice Age – entailed the slow degradation of cones and slower sedimentation of tufas, while the intensified physical weathering led to the increase in the clast material proportion (sharp-edged limestone fragments). Tufas accumulated in the zone unaffected by high anthropogenic pressure and thus represent a record of natural environmental changes during the historic period

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Interdisciplinary studies of spring mire deposits from Radzików (South Podlasie Lowland, east Poland) and their significance for palaeoenvironmental reconstructions

86%

Dobrowolski R. , Pidek I. A. , Alexandrowicz W. P. , Hałas S. , Pazdur A. , Piotrowska N. , Buczek A. , Urban D. , Melke J.

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tom Vol. 39, no. 1

10-29

EN

The paper presents the results of interdisciplinary (multi-proxy) palaeoenvironmental studies of peat – calcareous tufa depositional sequences of spring mire from Radzików site (east Poland). Analyses of three biotic proxies (plant macrofossils, pollen, molluscs) were supplemented with sedi-mentological, geochemical, oxygen and carbon stable isotopes analyses and radiocarbon dating and used for reconstruction of environmental changes in Late Glacial and Holocene. The obtained results enable us to (1) reconstruct main phases of mire development and (2) determine environmental fac-tors influencing changes of water supply. The object started to develop in Allerød. The Late Glacial and Early Holocene deposit sequence is relatively thick (about 1.0 m), with good palaeoecological record. The boundary between Younger Dryas and Preboreal is especially well confirmed by palynological and malacological analyses as well as radiocarbon dating. The Mesoholocene deposits are considerably worse preserved. Mire develop-ment was evaluated in terms of general mire ecology.

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Protection of calcareous tufa sites in southern Poland

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Alexandrowicz W. P.

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tom Vol. 13

119-124

EN

Calcareous tufa accumulated during the Late Glacial and Holocene reflect the changes of the environment. Numerous profiles of the mentioned deposits have been described from southern Poland. Profiles of calcareous tufa can be studied using various methods including conditions of sedimentation, geochronology, palaeotemperatures as well as plants and animals remains. Results of these analyses are the basis of the reconstruction of the palaeoenvironment, climatic changes and human impact. Selected localities of the mentioned deposits, representing the most complete sequences, should be promoted to the international geological heritage list.

PL

Martwice wapienne tworzące się w czasie późnego glacjału i holocenu odzwierciedlają zmiany środowiska. Liczne stanowiska tych osadów zostały opisane w południowej Polsce. Profile martwic wapiennych mogą być badane z użyciem różnorodnych metod obejmujących analizę procesów sedymentacji, paleotemperatur, aspekty geochronologiczne, a także badania szczątków roślinnych i zwierzęcych. Wyniki tych analiz stanowią podstawę dla rekonstrukcji paleośrodowiska, zmian klimatycznych oraz wpływu człowieka. Wybrane profile martwic wapiennych, reprezentujące najbardziej kompletne sekwencje, powinny zostać wpisane na międzynarodową listę dziedzictwa geologicznego.

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Application of malacological analysis in local and regional palaeoenvironmental reconstructions - a study from the Holocene of Łapsze Niżne (Podhale, southern Poland)

58%

Alexandrowicz W. P. , Szymanek M. , Rybska E.

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tom Vol. 68, no. 1

89--105

EN

This malacological analysis was conducted at a site with peat and calcareous tufas in Łapsze Niżne, Podhale (southern Poland). The study was carried out in 6 main and several complementary sections, in which 37 mollusc species were recognized represented by almost 11 000 specimens. The study enabled the reconstruction of environmental changes during the accumulation of the Holocene deposits (from the Boreal Phase till present). Conclusions drawn from these reconstructions were compared with results of malacological and palynological studies from other sites in Podhale. As a result, regional environmental reconstructions for the Holocene of the area were made. The specific composition, ecological structure and succession of molluscan assemblages from Łapsze Niżne indicate a significant role for local factors, thus demonstrating the variability of environmental conditions within a geographic region.