title: Oil removal and effects of spilled oil on active microbial communities in close to salt-saturation brines.
abstract: Abiotic and biotic processes associated with the degradation of a light petroleum in brines close to the salt-saturation (~31 %) and the effect of labile organic matter (LOM) supply (casaminoacids/citrate; 0.2 and 0.1 % w/v, respectively) were followed during an incubation of 30 days. After 4-week incubation at 40 °C under light/dark cycles, a 24 % of abiotic degradation was observed in untreated brines. The stimulation of native brines community with LOM addition allowed an additional 12.8 % oil attenuation due to biodegradation processes. Successional changes in the active microbial community structure due to the oil contamination (16S rRNA DGGE approach) showed the selection of one phylotype affiliated to Salinibacter and the disappearance of Haloquadratum walsbyi in untreated brines. In LOM-amended microcosms, phylotypes related to Salinibacter, Haloarcula, Haloterrigena and Halorhabdus were selected. An effect of hydrocarbon contamination was only observed in the bacterial community with the inhibition of two dominant proteobacterial phylotypes. This study further confirms that short-term and moderate oil biodegradation is possible in LOM-stimulated brines. Biodegradation should be much more reduced under in situ conditions. Self-cleaning capacities of close to saturation hypersaline lakes appears, therefore very limited compared to non-extreme haline environments.
authors.affiliation: Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, Campus de Luminy, Case 901, 163 Avenue de Luminy, 13288, Marseille Cedex 09, France. corsellis.yannick@gmail.com.
authors.forename: Yannick Y
authors.initials: YY
authors.lastname: Corsellis
authors.affiliation: Oceanological Observatory of Banyuls, UMR 7232, Banyuls-sur-mer, 66650, France.
authors.forename: Marc M
authors.initials: MM
authors.lastname: Krasovec
authors.affiliation: Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, Campus de Luminy, Case 901, 163 Avenue de Luminy, 13288, Marseille Cedex 09, France.
authors.forename: Léa L
authors.initials: LL
authors.lastname: Sylvi
authors.affiliation: Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, Campus de Luminy, Case 901, 163 Avenue de Luminy, 13288, Marseille Cedex 09, France.
authors.forename: Philippe P
authors.initials: PP
authors.lastname: Cuny
authors.affiliation: Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, Campus de Luminy, Case 901, 163 Avenue de Luminy, 13288, Marseille Cedex 09, France.
authors.forename: Cécile C
authors.initials: CC
authors.lastname: Militon
mesh_terms: D052918:Environmental Restoration and Remediation; D016931:Halobacteriales / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D060106:Lakes / Q000737:chemistry / Q000382:microbiology*; D064307:Microbiota; D010578:Petroleum / Q000378:metabolism / Q000382:microbiology*; D059392:Petroleum Pollution; D054712:Salinity; D012492:Salts
chemical_list: D010578:Petroleum; D012492:Salts; C017082:brine
keywords: 16S rRNA; Active bacterial and archaeal communities; DGGE; Hydrocarbon biodegradation; Hydrocarbonoclastic strains; Hypersaline water