Transport and dispersion of particulate Hg associated with a river plume in coastal Northern Adriatic environments.
The role of suspended particulate matter (SPM) as an important carrier of mercury (Hg) dispersed into the Gulf of Trieste and in the adjacent Grado lagoon (Northern Adriatic Sea) was studied during a high Isonzo River inflow and the resulting river plume formation. Despite the fact that extreme flood events are rare during the year, they account for most of the PHg influx (37-112 ngL(-1)) into the Gulf of Trieste. When the river plume is diverted to the SW under the influence of an E-NE wind, the tidal flux acts as a "transport belt" carrying the PHg, mostly inorganic, into the Grado lagoon. A preliminary estimation indicates that the amount of PHg entrapped in the lagoon basin following a tidal semi-cycle accounts for 1.4 kg/12h, which corresponds to about 49% of the total Hg carried by the tidal flow. These findings should be considered in future remediation strategies in the lagoon environment.
Covelli
Stefano
S
Department of Geological, Environmental and Marine Sciences, University of Trieste, Via Weiss 2, 34127 Trieste, Italy. covelli@univ.trieste.it
Piani
Raffaella
R
Acquavita
Alessandro
A
Predonzani
Sergio
S
Faganeli
Jadran
J
D002244:Carbon / Q000032:analysis; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000032:analysis; D007558:Italy; D008628:Mercury / Q000032:analysis*; D008767:Methylmercury Compounds / Q000032:analysis; D009792:Oceans and Seas; D010316:Particle Size; D045483:Rivers / Q000737:chemistry; D012623:Seawater / Q000032:analysis*; D014872:Water Movements; D014877:Water Pollution, Chemical / Q000032:analysis*; D014919:Wind
D008767:Methylmercury Compounds; D002244:Carbon; D008628:Mercury