Midges’ marks – what chironomid head capsules tell us about Eemian and Early Vistulian palaeoenvironment – results from Bispingen , northern Germany

Abstract

Understanding the nature of past climatic changes is essential to assess human impact on current and future climate and environment. One of the means to achieve this goal is conducting past climate reconstructions based on subfossil Chironomidae remains. Using this method allows to estimate past summer temperatures and other palaeoecological parameters such as lake trophy and pH. Although Chironomidae analysis is very useful for reconstructing past climatic and ecological conditions, not many high resolution reconstructions have been conducted for periods prior to significant human impact, e.g. during the Eemian interglacial and Early Vistulian glacial. The present study is part of a larger project that applies a multi-proxy approach to the partially annually laminated sediments of the Eemian paleolake of Bispingen in northern Germany. The analysed sediment sequence consists of around 12 meters of diatomitic, calcitic-diatomitic and clastic-organic material and was sampled continuously at 2 cm resolution. The aim of this research is to reconstruct summer temperature changes throughout the Early Vistulian glacial and Eemian interglacial and draw conclusions with respect to the climatic gradient between northern and southern Europe. Chironomids’ head capsules analysis is supported by palaeoecological and palynological data, allowing to extract distinct palaeoecological phases on the basis of trophy and thermal conditions during the period considered.   This project is funded by the Polish National Science Centre (No. 2019/34/E/ST10/00275).