A detailed malacological analysis was made of sediments associated with a small landslide which had developed on the north-eastern slope of Majerz Hill near Niedzica (Inner Carpathians, Southern Poland). The age of the development and environmental changes associated with particular phases of the landslide was determined by means of radiocarbon dating. The analyses made it possible to distinguish two periods of landslide activation falling on the turn of the Early/Middle Holocene and on the Late Holocene (probably on the Iron Age Cold Period). These phases are closely related to periods of increased mass movements, both of landslides and debris flows in other European mountains, stages of glacial advance in the Alps, periods of increased fluvial activity in rivers and elevated water levels in European lakes. The molluscan assemblages also enabled the reconstruction of environmental conditions before the landslide formation, during periods of dormancy, and after the end of its activity.
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
Late Glacial and Holocene carbonate lacustrine deposits developed as lacustrine chalk and calcareous gyttja are fairly widespread across northern Poland. They form fillings of palaeolakes which developed during the deglaciation. These formations are usually covered by peat. Rich and diversified malacofauna has been found in the aforementioned sediments. The profiles from 154 sites described and published by various authors were subjected to malacological analysis. In the whole material, 18 molluscan assemblages were distinguished, representing three types of habitats: terrestrial, of temporary water bodies, and of permanent water bodies. The composition and structure of these assemblages allows characterizing climate and differentiating habitats. The time-sequences of malacological assemblages provided possibility to define three types of malacological sequences. On the basis of these successions, a scheme of the lake water bodies evolution during Late Glacial and in northern Poland was elaborated.
Shells of subfossil snails and bivalves commonly noted in deposits of the Eemian Interglacial were used by several authors as more or less important stratigraphic indicators. In Poland, they have been noted in 35 sections, 20 of which are described as basic ones. Molluscan assemblages found at these sites include 60 species of freshwater molluscs and 58 species of land snails, the former being dominant. Climatic tolerance of particular species is the main attribute deciding on their stratigraphic values. Cold-tolerant snails are typical of the preceding Late Glacial and some of them occur also in early phases of the interglacial, while species connected with moderate climate and warm-demanding ones characterise the middle part of the Eemian Interglacial. The freshwater snail Belgrandia marginata is typical of the climatic optimum of this interglacial. Particular species of molluscs were related to regional pollen assemblage zones of the Eemian Interglacial in Poland.
Górnoholoceńskie martwice wapienne występują pospolicie na obszarze Beskidów Zachodnich. Często, choć nie zawsze, zawierają one miej lub bardziej bogate zespoły mięczaków. Analiza malakologiczna przeprowadzona została na podstawie materiału pochodzącego z 33 stanowisk reprezentowanych przez 59 próbek. Pozwoliła ona na opis najbardziej charakterystycznych zespołów mięczaków. Zostały wydzielone cztery typy i trzy podtypy fauny różniące się między sobą strukturą i składem gatunkowym. Malakofauna rozpoznana w omawianych osadach węglanowych jest ściśle uzależniona od lokalnych warunków. Spośród 68 rozpoznanych gatunków tylko kilka występowało licznie i w wielu profilach, podczas gdy pozostałe miały znaczenie akcesoryczne. Badania nad górnoholoceńskimi martwicami wapiennymi mają duże znaczenie dla rozpoznania mechanizmów tworzenia takich osadów węglanowych i zróżnicowania zespołów fauny. Stanowią one także podstawę rozważań aktuopaleontologicznych istotnych dla interpretacji paleogeograficznych i paleoekologicznych martwic holocenu oraz późnego glacjału występujących w południowej Polsce.
EN
Upper Holocene calcareous tufa occur commonly in the Western Beskidy Mts. Often, at least not always they contain more or less rich and differentiated molluscan assemblages. Malacological analysis was carried out on the basis of material collected from 33 localities represented by 59 samples. The most typical communities of snails and bivalves were characterized. Four types and three subtypes of fauna differing oneself in structure and species composition have been distinguished. Malacofauna recognized in discussed calcareous deposits is closely depended on local conditions. The whole material comprises 68 species, but only a few of them occur in large numbers and in many profiles, while the remaining ones had only accesorical importance. Malacological investigations of Upper Holocene calcareous tufa are important for recognizing mechanisms of deposition such calcareous sediments and differentiation of molluscan assemblages. They can be useful for actuopelaeontological analysis essential for palaeogeographical and palaeoecological interpretations of tufas of Holocene and Late Glacial age occurred in Southern Poland.
A profile of loess several metres thick with palaeosoils, underlain by calcareous gyttja, out crops in Kolodiiv, Ukraine. Rich and diverse assemblages of molluscs have been found in these deposits. Three types of mollusc communities can be distinguished. The oldest is dominated by freshwater taxa and corresponds to calcareous gyttja of Eemian age. The next two assemblages contain only snails typical of loess. The first of these indicates a cold and dry climate and open environment of arctic steppe type, with rapid accumulation of loess; the second assemblage represents a cold and humid climate and a relatively moist, open environment of tundra type.
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The sequence of three molluscan assemblages characterizing changes of the climate was found in the section of the middle and upper Vistulian loess. The first assemblage includes a relatively rich fauna with Arianta arbustorum, corresponding with the interpleniglacial or interstadial. Assemblages with Succinea oblonga and Pupilla loessica occur in the upper part of loess covering deposits of the bone-bed type. They point to the cold-humid and cold-dry phases of the Vistulian pleniglacial, respectively.
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Deposits accumulated in small karst forms are widespread in the Częstochowa Upland. Loam abounding in limestone lumps and scree, and initial rendsina-type soils are the two main types of these sediments. Shells of molluscs occur frequently in both types of them. Molluscan assemblages are composed of land snails including woodland, open-country and mesophile species. Particular communities correspond with present-day fauna of molluscs living within the Częstochowa Upland. Mollusc-bearing cave and slope sediments have been collected from twenty-five logs deriving from eighteen localities. Deposits filling small karst forms and rendsina soils are connected with the Upper Holocene, especially with the Historical Period.
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