title: Bacterial uptake of DOM released from P-limited phytoplankton.
abstract: The growth and the structure of a coastal bacterioplankton community were monitored in short-term bottle experiments in order to investigate the bacterial uptake of extracellular organic carbon released by the diatom Cylindrotheca closterium grown under P-balanced and P-depleted conditions. Bacterial specific growth rates and carbon demand were significantly lower in the exudates from P-depleted algae (24% and 30% reduction, respectively). The origin of the extracellular carbon appeared also to affect the taxonomic composition of the bacterioplankton assemblage, mainly reducing the development of gamma-Proteobacteria. This pattern of bacterial carbon uptake could contribute to a longer persistence of the exudates released in P-depleted conditions affecting the dynamics of the carbon cycle in marine environments.
authors.affiliation: Istituto di Ricerca Sulle Acque, CNR, Via Reno 1, 00198 Rome, Italy. puddu@irsa.rm.cnr.it
authors.forename: Alberto
authors.initials: A
authors.lastname: Puddu
authors.forename: Annamaria
authors.initials: A
authors.lastname: Zoppini
authors.forename: Stefano
authors.initials: S
authors.lastname: Fazi
authors.forename: Michela
authors.initials: M
authors.lastname: Rosati
authors.forename: Stefano
authors.initials: S
authors.lastname: Amalfitano
authors.forename: Erika
authors.initials: E
authors.lastname: Magaletti