Behaviour and fate of urban particles in coastal waters: Settling rate, size distribution and metals contamination characterization
|Author(s)||Oursel B.1, Garnier C.1, Pairaud Ivane2, Omanovic D.3, Durrieu G.1, Syakti A. D.4, 5, Le Poupon C.1, Thouvenin Benedicte6, Lucas Y.1|
|Affiliation(s)||1 : Univ Toulon & Var, PROTEE, EA 3819, F-83957 La Garde, France.
2 : IFREMER, Ctr Mediterranee, Lab Environm Ressources Provence Azur Corse, F-83507 La Seyne Sur Mer, France.
3 : Rudjer Boskovic Inst, Ctr Marine & Environm Res, Zagreb 10002, Croatia.
4 : Aix Marseille Univ, LCE FRE 3416, Equipe MPO, Europole Arbois, F-13545 Aix En Provence 4, France.
5 : Univ Jenderal Soedirman, Fac Sci & Tech, Fisheries & Marine Sci Dept, Purwokerto, Indonesia.
6 : IFREMER, Ctr Brest, DYNECO, DYNECO PHYSED, F-29280 Plouzane, France.
|Source||Estuarine Coastal And Shelf Science (0272-7714) (Academic Press Ltd- Elsevier Science Ltd), 2014-02 , Vol. 138 , P. 14-26|
|WOS© Times Cited||25|
|Keyword(s)||particles contamination, urban rivers, coastal zone, TWW, hydro sedimentation modelling|
|Abstract||The evaluation of contaminant net fluxes from the coast to the open sea requires the study of terrigeneous particles behaviour and fate. We studied the particles issued from two small coastal rivers whose waters are mixed with treated wastewater (TWW) coming from the Marseille wastewater treatment plant (WWTP) just before discharge to the Mediterranean Sea. An experimental device was developed and used to investigate particles settling rates, size distribution and metallic contamination when mixing with seawater. The particles were sampled in flood deposits of rivers and outlets during rainy periods and in the outlet water during dry periods. The flood deposits were mainly composed of 50–200 μm-sized particles, higher metals content being observed in the finest fractions. Dry period particles showed the stronger influence of wastewater inputs. Al, Ca, Cs, Li, Rb, Ti, and Tl were mainly of terrigeneous origin, whereas Ag, Ba, Cd, Cr, Cu, Hg, Mg, Mo, Ni, Pb, POC, Sb, Sn and Zn were of anthropogenic origin, issued from non-treated sewage, TWW or industrial waste. In seafloor sediments, all metals exhibited a continuous increase of concentration from the outlet to, at least, 800 m offshore. Implementation of settling particles characteristics in a 3D hydrodynamic and sediment transport model reproduced well the observed deposition of polluted particles in the coastal zone and indicated a non-negligible offshore export of the finest particles and their accompanying pollutants.|