Past environment and climate changes at the last Interglacial/Glacial transition (Les Échets, France) inferred from subfossil chironomids (Insecta)

Emmanuel Gandouin (1) , Philippe Ponel (1) , Valérie Andrieu-Ponel (1) , Evelyne Franquet (1) , Jacques-Louis de Beaulieu (2) , Maurice Reille (2) , Frédéric Guiter (1) , Jacques Brulhet (3) , Elisabeth Lallier-Vergès (4) , Didier Kéravis (4) , Ulrich von Grafenstein (5, 6, 7) , Daniel Veres (8)

1 IMBE - Institut méditerranéen de biodiversité et d'écologie marine et continentale
2 IMEP - Institut Méditerranéen d'Ecologie et de Paléoécologie
3 ANDRA - Agence Nationale pour la Gestion des Déchets Radioactifs
4 ISTO - Institut des Sciences de la Terre d'Orléans
5 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
6 GEOTRAC - Géochrononologie Traceurs Archéométrie
7 GLACCIOS - Glaces et Continents, Climats et Isotopes Stables
8 Department of Physical Geography and Quaternary Geology

Subfossil chironomid assemblages spanning the last Interglacial/Glacial transition at Les Échets (France) highlight the environmental and climatic changes that took place at this crucial period. The Early Eemian warming is marked by increased percentages of warmwater taxa and decreased percentages of coldwater taxa. In the Middle Eemian, a lowering in water level is indicated by a rise of littoral taxa. In the Late Eemian, chironomids indicate anoxic deep waters and rise of water level, probably induced by increased rainfall. Mélisey I and II and the beginning of the glacial period are marked by the reappearance of coldwater taxa, lower percentages of warmwater taxa, and dominance of littoral taxa, probably correlated with lower water level and climate aridity. St Germain I and II are marked by higher percentages of warmwater taxa, lower percentages, or absence of both coldwater and littoral taxa.

Mots clés: Chironomids; Palaeolimnology; Palaeoenvironment; Mid Europe; Climate change; Lake water level

Domaines: Climatologie; Interfaces continentales, environnement; Milieux et Changements globaux

Emmanuel Gandouin, Philippe Ponel, Valérie Andrieu-Ponel, Evelyne Franquet, Jacques-Louis de Beaulieu, et al.. Past environment and climate changes at the last Interglacial/Glacial transition (Les Échets, France) inferred from subfossil chironomids (Insecta). Comptes Rendus Géoscience, 2007, 339 (5), pp.337-346. ⟨10.1016/j.crte.2007.03.002⟩. ⟨insu-00203126⟩