First steps towards the reconstruction of land use in the medieval Fluvial Anthroposhere of the Echaz floodplain (Southwest Germany)

The Echaz River is a third-order karst river and a tributary of the Rhine. It originates in the Swabian Alb and cuts a cuesta landscape until it flows into the Neckar River. Structural changes to the natural course and floodplain of the Echaz are mainly due to the exploitation of its water power by mills and the irrigation of the so-called „water meadows“ during the Middle Ages (the water meadows appear in written sources as early as 1289, the mills in 1138 in Reutlingen, and in 1297 in Pfullingen).

This study presents the first steps towards a multidisciplinary reconstruction of the Fluvial Anthroposphere, by investigating local medieval pathways and land use in parts of the Echaz floodplain upstream of Pfullingen and downstream of Reutlingen. This reach of the Echaz was a centre of crafts, tanneries, dyeing and paper manufacturing in the Middle Ages. The upstream sites represent areas of anthropogenic influence, with water meadows presumably established in the High Middle Ages, while the sediments and soils of the downstream sites have archived signals of medieval and early modern craft activities (such as heavy metals: chromium, copper, iron, nickel, lead, zinc).

These first steps of research comprise the digitisation of old maps combined with information from historical and archaeological archives. A digital relief model in combination with geophysical results from Electromagnetic Induction (EMI) and, Electrical Resistivity Tomography (ERT) are correlated with soil profiles and soil/sediment cores from the Echaz floodplain, and form the basis for the reconstruction of natural and anhtropogenic stratigraphies.

Future work will include the establishment of a chronostratigraphic model with luminescence ages of sediments and radiocarbon dates of charcoal fragments, which will provide the basis for the selection of suitable sites for further analysis, including a combination of digital historical maps and physical-biogeochemical analyses (enzymes for excrement input, polycyclic aromatic hydrocarbons [PAH] for fire use), stable isotope ratios of C and N for the differentiation of C₃ and C₄ plants, as well as XRF analysis (for heavy metal pollution) as well as mollusc and ostracod analyses for aquatic habitat and water quality reconstruction.