LOESS AND UPPER WEICHSELIAN ENVIRONMENT IN THE CARPATHIAN BASIN (EUROPE)

Most species of the Quaternary Mollusc fauna exist even today thus their extrapolation for the Quaternary is feasible. Quaternary malacological studies give the most detailed information about palaeoenvironmental, palaeoclimatological conditions of the Quaternary periods. First of all for times of loess deposition, because Mollusc shells are well preserved in these layers. The species composition of land snail assemblages is largely dependent on microclimatic conditions and factors of local habitat, especially vegetation cover. The Quaternary malacological analysis of the loess area in the Carpathian Basin is quite promising, since indicator species of various palaeoecological conditions appeared and migrated rapidly from different palaeobiogeographical parts of Europe, primarily from the lower Danube region. The Late Pleistocene environmental history of the Carpathian Basin can be regarded as one of the missing links to our understanding of the last glacial development of Europe. In terms of its location and geology the Carpathian Basin provides an important unglaciated area of low relief within the main mountain ranges of Central Europe (Carpathians, Alps, Dinaric Alps). We collected fine-stratigraphic samples from 29 Late Pleistocene loess sequences for sedimentological, quartermalacological analysis and radiocarbon dating. Chronology was obtained from 121 radiocarbon age determinations.Changes in the Mollusc fauna refer to nine short-lived (1000 - 3000 years), cyclical palaeoclimatological alterations, which repeatedly transformed the palaeoecological conditions and vegetation in the Carpathian Basin between 34 – 12 kyr. On the other hand the composition of the Quaternary Molluscs suggest that the Upper Weichselian environment was mosaic-like and inhomogeneous in the analysed region with the development of some palaeoecological barriers parallel on the micro-, meso-, and macro level. According to the Quaternary Mollusc fauna the Carpathian Basin was a large fluctuation and migration zone between the different palaeobiogeographic units of Europe. Furthermore two forest types, some grasslands, and forest steppes can be reconstructed for the Upper Weichselian.