Building up stages of a Mediterranean delta: Climatic changes and anthropogenic forcing in the Adra River delta

Abstract

The evolutionary stages of the submarine delta off the Adra River are investigated in this study, under the context of climatic fluctuations entangled with increasing human activities and interventions in the drainage basins and adjacent shores during the Middle to Late Holocene. To achieve that goal, we used an extensive database comprising a set of bathymetric data covering different time slices, a dense grid of high-resolution seismic data and several sediment cores collected in the two submarine lobes of the Adra River delta. Two main evolutionary phases can be identified. The first one extended through most of the construction history and was mediated by major climatic events at the Mediterranean scale; this phase included three major progradational events occurring during the Mid Holocene, the Roman time and the Little Ice Age. The most recent phase is strongly determined by human modifications of the fluvial channels, and resulted in a drastic transformation of the submarine sedimentary environment.