8000 years of coastal changes on a western Mediterranean island: A multiproxy approach from the Posada plain of Sardinia

A multi-proxy palaeoenvironmental investigation was conducted to reconstruct the Holocene history of coastal landscape change in the lower Posada coastal plain of eastern Sardinia. In the Mediterranean region, coastal modifications during the Holocene have been driven by a complex interplay between climate, geomorphological processes and human activity. In this paper, millennial-scale human-sea level-environment interactions are investigated near Posada, one of the largest coastal plains in eastern Sardinia. Biostratigraphic and palynological approaches were used to interpret the chrono-stratigraphy exhibited by a series of new cores taken from the coastal plain. This new study elucidates the main paleoecological changes, phases of shoreline migration and relative sea-level change during the last 8000 years. These results indicate the major role of sea-level stabilization and high sediment supply in driving major landscape changes, especially during the Neolithic period (6th-4th millennia BC), and the long-term settlement history of this coastal valley area. It is concluded that human occupation of the coastal plain, from prehistoric to historical times, was most likely constrained by the rapid and constant evolution of this coastal landscape.