title: Spatio-temporal variation of suspended and sedimentary organic matter quality in the Bay of Marseilles (NW Mediterranean) assessed by biochemical and isotopic analyses.
abstract: Isotopic and biochemical features of suspended particulate organic matter (POM) in the water column and of sedimentary organic matter (SOM) were investigated seasonally in the Bay of Marseilles. Biochemical compounds (carbohydrates, lipids and proteins) were consistently more concentrated in POM than in SOM, with SOM mainly composed of insoluble carbohydrates. POM displayed lower δ(13)C and higher δ(15)N values than SOM. Phytoplanktonic production represented the major contributor of POM year-round with spatial and seasonal variations. Climatic parameters and wind-induced currents created differences in POM contributions, with more important inputs of terrestrial OM at one sampling site. Spatial and seasonal variations were lower for SOM. The composition of this pool appeared to be linked with the permanent inputs of phytoplankton and Posidonia oceanica detritus. The combined use of biochemical and isotopic analyses was a useful tool to characterize OM pools and would help understanding the trophic functioning of this coastal environment.
authors.affiliation: Aix-Marseille Univ., UMR CNRS 7294, Mediterranean Institute of Oceanography, 13288 Marseille Cedex 09, France. pierre.cresson@univ-amu.fr
authors.forename: Pierre
authors.initials: P
authors.lastname: Cresson
authors.forename: Sandrine
authors.initials: S
authors.lastname: Ruitton
authors.forename: Marie-France
authors.initials: MF
authors.lastname: Fontaine
authors.forename: Mireille
authors.initials: M
authors.lastname: Harmelin-Vivien
mesh_terms: D061006:Bays / Q000737:chemistry*; D002247:Carbon Isotopes / Q000032:analysis; D002980:Climate; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry; D009587:Nitrogen Isotopes / Q000032:analysis; D010839:Phytoplankton; D012621:Seasons; D014873:Water Pollutants / Q000032:analysis*; D014876:Water Pollution / Q000706:statistics & numerical data; D060753:Water Quality / Q000592:standards
chemical_list: D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D014873:Water Pollutants