Observations on gravel moving on the foreshore and the backshore have been performed on a mixed sand and gravel beach of Northern Tuscany (Italy) subject to erosive processes. In addition to the gravel naturally transported by Magra River, a large amount of gravel has been discharged by human activity through nourishments as part of a series of protection systems. Two transects, with an average spacing of 500 m, were carried out parallel and perpendicular to the coast-line on the beach-face and on the step, and gravel deposits and cusps evolution were monitored. The study was performed following sea-weather changes, in order to obtain data during fair-weather and storm-weather conditions, and shortly after storm decay. The results confirm the existence of a south-directed longshore drift. At the same time, it seems that gravel clasts are no more present on the backshore during major storms. These observations allow to distinguish five phases within a fair-weather to storm-weather cycle and to determine the response of gravel movement to sea-weather conditions.
Monitoring backshore and foreshore gravel deposits on a mixed sand and gravel beach (Apuane-Versilia coast, Tuscany. Italy)
SARTI, GIOVANNI;Bertoni D.
2007-01-01
Abstract
Observations on gravel moving on the foreshore and the backshore have been performed on a mixed sand and gravel beach of Northern Tuscany (Italy) subject to erosive processes. In addition to the gravel naturally transported by Magra River, a large amount of gravel has been discharged by human activity through nourishments as part of a series of protection systems. Two transects, with an average spacing of 500 m, were carried out parallel and perpendicular to the coast-line on the beach-face and on the step, and gravel deposits and cusps evolution were monitored. The study was performed following sea-weather changes, in order to obtain data during fair-weather and storm-weather conditions, and shortly after storm decay. The results confirm the existence of a south-directed longshore drift. At the same time, it seems that gravel clasts are no more present on the backshore during major storms. These observations allow to distinguish five phases within a fair-weather to storm-weather cycle and to determine the response of gravel movement to sea-weather conditions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
