The coastal area we studied has a NW-SE orientation and it is cut in the middle by the Sarno River. The beach is sandy and it has superficial accumulations of flattened gravels. The gravels, reworked by the sea action, are likely linked to a dejection phase of the Sarno River and of its streams (Gragnano – S. Marco and Calcarella). This process was studied in the Sarno coastal plain and it is verified during the maximum marine ingression related to the Holocene sea-level highstand (5.8 ky BP).
At present the beach is eroding overall, reaching a width that ranges from 15 to 30 m, with the exception of two triangular-shaped sectors in progradation at the extremities, adjacent to the harbour’s inner breakwaters of Torre Annunziata (wide beach of up to 200 m) and of Castellammare di Stabia (wide beach of up to 150 m). The sand towards the North is predominantly of volcanic origin and of dark gray colour. Gradually, starting from the intermediate stretch, it becomes carbonate, assuming S shades that are always clearer than gray. Its nature is to be ascribed to the lithology of the geological complexes that are present at the boundaries of the physiographic unit.
Author(s) Details:
Giuseppe Pecoraro
Giunta Regione Lombardia, Milano, Italy.
Micla Pennetta
Università degli Studi di Napoli “Federico II”, Napoli, Italy.
Recent global research developments in Coastal Dynamics and Sediment Characteristics of Sarno River Estuary
- Estuarine Morphology and Dynamics:
- The Sarno River Estuary is a transgressive coastal environment at the mouth of the Sarno River. It receives sediment from both fluvial (river) and marine sources.
- The estuary extends from the landward limit of tidal facies at its head to the seaward limit of coastal facies at its mouth.
- Sediment dynamics play a crucial role in shaping the estuary’s morphology. The coarsest sediments are found at the estuarine mouth, where strong tide- and wave-induced currents act on the bed. Fine sediments are deposited on the tidal flats and in the inland channels [1].
- The estuary’s morphology is influenced by three main factors:
- Tide: Characterized by the mean spring tidal range.
- Wave: Characterized by significant storm wave height and corresponding incidence angle.
2. Sediment Distribution and Characteristics:
- Sediment distribution in the Sarno River Estuary reveals distinct patterns:
- Sediments from the Sarno River prevail in the central part of the bay.
- Sand-grained deposits from Mount Vesuvius and coarser-grained sediments from the Sorrento Peninsula also contribute to the sediment mix.
- The Sarno River deposition consists of silt/clays rich in organic elements with a high water content [2].
3. Hydrodynamics and Saltwater Intrusion:
- Saltwater intrusion occurs due to weak river discharge during the dry season.
- An estuarine turbidity maximum zone forms near specific stations due to the combined effects of tides, river discharge, and saltwater intrusion [3].
References
1. Morphology of estuaries
https://www.coastalwiki.org/wiki/Morphology_of_estuaries
2. Di Leo, A., Giandomenico, S., Spada, L., Cardellicchio, N., Buonocunto, F. P., Esposito, E., … & Violante, C. THE OFFSHORE ENVIRONMENTAL IMPACT BY SARNO RIVER IN NAPLES BAY (SOUTH-WEST ITALY). https://library.oapen.org/handle/20.500.12657/56123
3. Kalhoro N.A., He Z., Li L., Xu, D., Jun W., Zeb A. and Khaskheli N. (2021), Spatial and temporal variations of hydrodynamics and sediment. dynamics in Indus River Estuary, Pakistan, Global NEST Journal, 23(4), 572-580.https://journal.gnest.org/publication/gnest_03333
4. Li, X., Cai, Y., Liu, Z., Mo, X., Zhang, L., Zhang, C., … & Ren, Z. (2023). Impacts of river discharge, coastal geomorphology, and regional sea level rise on tidal dynamics in Pearl River Estuary. Frontiers in Marine Science, 10, 1065100.