Résumé
A high-resolution malacological study (1 sample for 10 cm) realised on the Nussloch loess sequence (Germany) in the Rhine valley has yielded its first results. The aim of this work is the search of rapid variations of climate and/or environment in continental domain. Between 19 and 31 ky cal. BP, the sedimentological dilatation is exceptional (X10 m), and strong variations in both the diversity index and the abundance are observed, and show that rapid global climate changes, at a millennial-time scale, occurred during this period. These variations are correlated with both the lithological changes and the grain size index, which characterises the aeolian dynamics, determined in the same sequence. The variations of the proxies indicate that the deposition of each of the nine identified gley-loess doublets is by three successive climatic changes. Thus, this indicate a great sensibility of loess environments to millennial climatic changes.