Dynamics of bacterial assemblages and removal of polycyclic aromatic hydrocarbons in oil-contaminated coastal marine sediments subjected to contrasted oxygen regimes

Abstract : To study the impact of oxygen regimes on the removal of polycylic aromatic hydrocarbons (PAHs) in oil-spill-affected coastal marine sediments, we used a thin-layer incubation method to ensure that the incubated sediment was fully oxic, anoxic, or was influenced by oxic-anoxic switches without sediment stirring. Hydrocarbon content and microbial assemblages were followed during 60 days to determine PAH degradation kinetics and microbial community dynamics according to the oxygenation regimes. The highest PAH removal, with 69 % reduction, was obtained at the end of the experiment under oxic conditions, whereas weaker removals were obtained under oscillating and anoxic conditions (18 and 12 %, respectively). Bacterial community structure during the experiment was determined using a dual 16S rRNA genes/16S rRNA transcripts approach, allowing the characterization of metabolically active bacteria responsible for the functioning of the bacterial community in the contaminated sediment. The shift of the metabolically active bacterial communities showed that the selection of first responders belonged to Pseudomonas spp. and Labrenzia sp. and included an unidentified Deltaproteobacteria—irrespective of the oxygen regime—followed by the selection of late responders adapted to the oxygen regime. A novel unaffiliated phylotype (B38) was highly active during the last stage of the experiment, at which time, the low-molecular-weight (LMW) PAH biodegradation rates were significant for permanent oxic- and oxygen-oscillating conditions, suggesting that this novel phylotype plays an active role during the restoration phase of the studied ecosystem.
Type de document :
Article dans une revue
Environmental Science and Pollution Research, Springer Verlag, 2015, 22 (20), pp.15260-15272. 〈10.1007/s11356-015-4510-y〉
Liste complète des métadonnées

Littérature citée [60 références]  Voir  Masquer  Télécharger

https://hal.archives-ouvertes.fr/hal-01233392
Contributeur : Open Archive Toulouse Archive Ouverte (oatao) <>
Soumis le : mercredi 25 novembre 2015 - 09:50:39
Dernière modification le : jeudi 7 juin 2018 - 07:08:02
Document(s) archivé(s) le : vendredi 26 février 2016 - 12:13:44

Fichier

militon_14472.pdf
Fichiers produits par l'(les) auteur(s)

Identifiants

Citation

Cécile Militon, Ronan Jezequel, Franck Gilbert, Yannick Corsellis, Léa Sylvi, et al.. Dynamics of bacterial assemblages and removal of polycyclic aromatic hydrocarbons in oil-contaminated coastal marine sediments subjected to contrasted oxygen regimes. Environmental Science and Pollution Research, Springer Verlag, 2015, 22 (20), pp.15260-15272. 〈10.1007/s11356-015-4510-y〉. 〈hal-01233392〉

Partager

Métriques

Consultations de la notice

395

Téléchargements de fichiers

127