Lake evolution and landscape history in the lower Mincio River valley, unravelling drainage changes in the central Po Plain (N-Italy) since the Bronze Age

The Etruscan harbour of Forcello in lower valley of the Mincio River, N-Italy, was active between 540 and 390 yr BC. The stratigraphic investigations revealed that the settlement occupied a hill on the shore of a large lake. The lake sediments and the palaeoecological record, supported by radiocarbon ages, documented the basin origin in the Middle Bronze Age as well as the development of aquatic and terrestrial vegetation trhough the Iron Age and the Roman age, until the Late Middle Age reclamation. The lake expanded during the early Iron Age, after the diversion of the Po River at Guastalla. The bed-load and sedimentation rates in the Po river system has been related to the lake development through damming at the confluence with the Mincio River. This circumstance allowed a new assessment of the Late Holocene palaeodrainage changes in the Central Po Plain. Subsidence related to local tectonics in the axial portion of the river network is a triggering factor, coupled with an increase of bed-load discharge. The latter resulted from a complex response to rising base-level of the Po Plain fluvial system, induced by increasing sea level. Bronze Age human pressure on forest may also have contributed to this bed-load increase.