Dredging works monitoring in the Port of Civitavecchia (Rome, Italy): sedimentological and geochemical investigations.

Since its creation in 2001, the Laboratory of Experimental Oceanology and Marine Ecology (DEB) of Tuscia University devoted a significant part of its studies to the characterization and assessment of the coastal marine environment near Civitavecchia (central Tyrrhenian Sea, Italy), and on the influence of climatic events, as well as anthropic activities on marine environment. The coastal area of Civitavecchia is characterized by multiple uses (e.g. industrial, commercial, touristic, ecological) which result in a complex series of effects on the marine ecosystem. Civitavecchia also hosts one of the most important European ports, where several expansion works over recent times have influenced the sedimentological, geochemical and ecological characteristics (e.g., benthic biocenoses and Posidonia oceanica) of the area. Extensive dredging works in the Civitavecchia harbour were performed between November 2012 and January 2013 to build new piers and docks. The potential impact of the dredging works was assessed through an extended environmental monitoring program which was performed before and after the dredging activities. In detail, during the monitoring activities, the chemical and physical characterization of the water column, marine sediments and the assessment of the possible impact of dredging activities on the benthic ecosystem were carried out. This paper reports the results of the monitoring activities of water and sediments carried out in the harbour area and in the adjacent environment. The increase of sediment fine fraction and the enrichment of trace metals in the offshore station could be induced by dredging activities. Previous works reports the assessment of the environmental conditions before and after the dredging operations where significant variations in the composition of the benthic biocenosis and the effects on Posidonia oceanica meadows were found.