Settlement potential and constraints on the lower Médoc coastline: results of the Litaq project and considerations on coastal palaeo‑risks in the protohistoric periods

The adaptation of territorial systems to the ongoing climate change is an issue which implies to test past populations abilities to cope, to “bounce back” or to adapt during similar past environmental changes. The chronostratigraphical and archaeological results, obtained in the frame of the LITAQ project, make it possible to better understand changes encountered by a coastal system (now on the shore front) whose intense occupation since the Neolithic period was linked to the exploitation of specific resources (salt, grazing), then inherent to a fluvial mouth and estuarine system, at present fossilized under the modern dune. One of the issues raised by these results is linked to the decline of salt-related activities during the whole Bronze period, whereas it is bracketed by a period of growing during the Neolithic (for which we were far from measuring the real amplitude) and by the first Iron Age during which salt production appears to be the main motivation for the settlement and the use of coastal marshes. However, the chronological gap, of about thirteen centuries, recorded between the Early Bronze Age (~2200 BC) and the Late Bronze Age (~900 BC), prevents us from using climate changes as a deterministic and unique factor of land-use changes of the Medoc Peninsula around the first millennium. The complex rhythms, that accompany those changes during this period and the subsequent Iron Age, invite us to consider the territorial vulnerability in a context of hydrogeomorphological modifications of the coast synchronously to those of natural components involved in the salt production process. Modalities of the spatial development of this activity (as deduced from the analysis of inventoried remains) in a context of restricted tidal exchanges (i.e. barred estuary), testify to the adaptability of protohistoric Medocan communities, which faced a slow and progressive disturbance of the coastal system; they attest also to the past resilience, in its systemic sense, of a territory nowadays far from major influences.