Spatio-temporal variability of fluorescent dissolved organic matter in the Rhône River delta and the Fos-Marseille marine area (NW Mediterranean Sea, France) - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Environmental Science and Pollution Research Année : 2017

Spatio-temporal variability of fluorescent dissolved organic matter in the Rhône River delta and the Fos-Marseille marine area (NW Mediterranean Sea, France)

Résumé

The spatio-temporal variability of fluorescent dissolved organic matter (FDOM) and its relationships with physical (temperature, salinity) and chemical (nutrients, chlorophyll a, dissolved and particulate organic carbon, nitrogen and phosphorus) parameters were investigated in inland waters of the Rhône River delta and the Fos-Marseille marine area (northwestern Mediterranean, France). Samples were taken approximately twice per month in two inland sites and three marine sites from February 2011 to January 2012. FDOM was analysed using fluorescence excitation-emission matrices (EEMs) coupled with parallel factor analysis (PARAFAC). In inland waters, humic-like components C1 (λEx/λEm: 250 (330)/394 nm) and C3 (λEx/λEm: 250 (350)/ 454 nm) dominated over one tryptophan-like component C2 (λEx/λEm: 230 (280)/340 nm), reflecting a background contribution of terrigenous material (~67% of total fluorescence intensity, in quinine sulphate unit (QSU)) throughout the year. In marine waters, protein-like material, with tyrosine-like C4 (λEx/λEm: <220 (275)/<300 nm) and tryptophan-like C5 (λEx/ λEm: 230 (280)/342 nm), dominated (~71% of total fluorescence intensity, in QSU) over a single humic-like component C6 (λEx/λEm: 245 (300)/450 nm). In inland waters of the Rhône River delta, humic-like components C1 and C3 were more abundant in autumn-winter, very likely due to inputs of terrestrial organic matter from rainfalls, runoffs and windinduced sediment resuspension. In marine sites, intrusions of the Berre Lagoon and Rhône River waters had a significant impact on the local biogeochemistry, leading to higher fluorescence intensities of humic- and protein-like components in spring-summer. On average, the fluorescence intensities of FDOM components C4, C5 and C6 increased by 33–81% under lower salinity. This work highlights the complex dynamics of FDOM in coastal waters and confirms the link between marine FDOM and the Rhône River freshwater intrusions on larger spatial and temporal scales in the Fos-Marseille marine area.
Fichier non déposé

Dates et versions

hal-01437536 , version 1 (17-01-2017)

Identifiants

Citer

Nicolas Ferretto, Marc Tedetti, C. Guigue, Stéphane Mounier, Patrick Raimbault, et al.. Spatio-temporal variability of fluorescent dissolved organic matter in the Rhône River delta and the Fos-Marseille marine area (NW Mediterranean Sea, France). Environmental Science and Pollution Research, 2017, 24 (5), pp.4973-4989. ⟨10.1007/s11356-016-8255-z⟩. ⟨hal-01437536⟩
327 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More