Stable isotope data from loess malacofauna: Evidence for climate changes in the Pannonian Basin during the Late Pleistocene

Loess is terrestrial clastic sediment, composed dominantly of silt-sized particles formed by the accumulation of wind-blown dust. It is usually inter-bedded with palaeosol horizons forming loess-palaeosol successions (LPS). Due to its characteristics loess represents a high quality record of climate changes in the Late Pleistocene. The thickest and best-studied loess sections in the Republic of Croatia are located in the eastern Croatian province of Baranja, near the Danube River. This area is a southern part of the Pannonian Basin. Zmajevas LPS was selected in this study. Grain-size distribution indicates that the loess from Zmajevac LPS in Baranja is typical loess, comparable with other loess profiles in the Pannonian Basin. The faunal assemblages in the loess samples prove the dominance of transitional palaeoecological assemblage types, whereas uniformly defined types are rare. Helicopsis striata assemblage is dominant, while Columella columella and Chondrula tridens assemblages are present in smaller proportion. For additional information about palaeoclimate and palaeoecology in Pannonian Basin, stable oxygen and carbon isotope ratios were measured in mollusc shells. Stable oxygen values range from 5.76? to 2.45?. Stable carbon isotope values range from 8.83? to 6.84?. Stable oxygen values show significant palaeotemperature changes during the Late Pleistocene, with the average growing season (AGS) temperature range of 13.24 °C or 9.457°C, depending on which formula is applied. The overall climate was much cooler then present. Stable carbon isotope values point to dominance of C3 vegetation type during the Late Pleistocene in southern part of the Pannonian Basin.