The scientists’ search focuses on the Holocene, an epoch that began at the end of the Ice Age about 11,700 years ago and extends to the present. Its first millennia coincide with the late phases of what archaeologists call the Stone Age, the oldest period of human history. Until now, one of the most striking features used by geoscientists to gauge very early human influence on landscape changes in Central Europe, was overbank silt-clay deposition. Specifically, this is river deposits which, according to the understanding of decades of floodplain research, result from clearing in river catchments and the subsequent erosion of the bare soils by the water. In all Central European catchment areas used for agriculture, overbank silt-clay deposition has so far been regarded as a reliable indicator of such human influence on the environment, in some cases going back to the Neolithic period.
“The overbank silt-clay deposition from the Weiße Elster is internationally renowned in the scientific community. To date, it has been considered one of the oldest such overbank silt-clay depositions ever,” said Professor Christoph Zielhofer, physical geographer at Leipzig University: “However, we have doubts about this hypothesis, as our new results rather suggest that the overbank silt-clay originated in areas that were not influenced by Neolithic clearing activity, namely from the upper reaches of the river that would have been forested at that time.”
This is why a team of geography, archaeology and geophysics experts from Leipzig, Jena, Tübingen and Magdeburg is revisiting the fundamental question of when exactly humans began changing the landscapes around them, as Zielhofer explains: “There are indeed clear scientific indications that we need to rethink the existing hypotheses, but I would say that we still have no conclusive proof.” Co-author and archaeologist Professor Ulrich Veit of Leipzig University puts the new findings in context: “We have compelling data, but it contrasts with previous research. At present we need to assume that there will also be further discussions in archaeology about this question.”
The study was conducted as part of a DFG project called “Imprints of Rapid Climate Changes and Human Activity on Holocene Hydro-Sedimentary Dynamics in Central Europe (Loess-Covered Weiße Elster Model Region)”. The project involves scientists from the Friedrich Schiller University Jena, the Otto von Guericke University of Magdeburg, the Eberhard Karl University of Tübingen, the Helmholtz Centre for Environmental Research Leipzig (UFZ) and Leipzig University.
Original title of the publication in Science of the Total Environment: “Overbank silt-clay deposition and intensive Neolithic land use in a Central European catchment – Coupled or decoupled?”, doi.org/10.1016/j.scitotenv.2021.150858