Spatio-temporal variation of suspended and sedimentary organic matter quality in the Bay of Marseilles (NW Mediterranean) assessed by biochemical and isotopic analyses

► We analyzed isotopic and biochemical values of OM pools in the Bay of Marseilles. ► Biochemical and δ15N values were higher in POM, δ13C values were higher in SOM. ► POM was mainly influenced by phytoplankton and occasionally by terrestrial inputs. ► SOM composition is linked with permanent OM inputs (phytoplankton and P. oceanica).