Water table fluctuation and assessment risk degradation of watterlogged sites: the site of la Draga (Banyoles, Spain)

Abstract

Pile dwelling sites in Mediterranean lakes face increasing threats to their conservation and safeguarding from climate change and its associated impacts. The primary objective of this study is to investigate the influence of climate change and water table fluctuations on the preservation of archaeological layers, with a particular focus on organic layers and wooden remains. Based on a combination of lake water level fluctuation analysis, water table measurements, and stratigraphic data, we managed to gauge the effects of recent water table fluctuations on the preservation of the occupation levels at the Neolithic site of La Draga (Lake Banyoles). By simulating and analysing the relationship between water table levels and their effects on the stratigraphic sequence, we were able to identify areas that are most susceptible to the impact of water table fluctuations and therefore potential post depositional processes. Moreover, statistical analysis of recent hydrological data has shown that there is a direct relationship between lake level and water table at the settlement. This would have been a factor affecting the preservation of both artefacts and deposits since the occupation of La Draga. Thus, the importance of considering hydrological factors when analysing and interpreting lakeside archaeological sites is highlighted.