Louati H., Ben Said O., Soltani A., Got P., Mahmoudi E., Cravo-Laureau C., Duran R., Aissa P., Pringault Olivier. (2013). The roles of biological interactions and pollutant contamination in shaping microbial benthic community structure. Chemosphere, 93 (10), p. 2535-2546. ISSN 0045-6535.
Titre du document
The roles of biological interactions and pollutant contamination in shaping microbial benthic community structure
Année de publication
2013
Auteurs
Louati H., Ben Said O., Soltani A., Got P., Mahmoudi E., Cravo-Laureau C., Duran R., Aissa P., Pringault Olivier
Source
Chemosphere, 2013,
93 (10), p. 2535-2546 ISSN 0045-6535
Biological interactions between metazoans and the microbial community play a major role in structuring food webs in aquatic sediments. Pollutants can also strongly affect the structure of meiofauna and microbial communities. This study aims investigating, in a non-contaminated sediment, the impact of meiofauna on bacteria facing contamination by a mixture of three PAHs (fluoranthene, phenanthrene and pyrene). Sediment microcosms were incubated in the presence or absence of meiofauna during 30 days. Bioremediation treatments, nutrient amendment and addition of a hydrocarbon-degrading bacterium, were also tested to enhance PAH biodegradation. Results clearly show the important role of meiofauna as structuring factor for bacterial communities with significant changes observed in the molecular fingerprints. However, these structural changes were not concomitant with changes in biomass or function. PAH contamination had a severe impact on total meiofaunal abundance with a strong decrease of nematodes and the complete disappearance of polychaetes and copepods. In contrast, correspondence analysis, based on T-RFLP fingerprints, showed that contamination by PAH resulted in small shifts in microbial composition, with or without meiofauna, suggesting a relative tolerance of bacteria to the PAH cocktail. The PAH bioremediation treatments were highly efficient with more than 95% biodegradation. No significant difference was observed in presence or absence of meiofauna. Nutrient addition strongly enhanced bacterial and meiofaunal abundances as compared to control and contaminated microcosms, as well as inducing important changes in the bacterial community structure. Nutrients thus were the main structural factor in shaping bacterial community composition, while the role of meiofauna was less evident.
Plan de classement
Ecologie, systèmes aquatiques [036]
;
Pollution [038]
Description Géographique
TUNISIE
Localisation
Fonds IRD [F B010061343]
Identifiant IRD
fdi:010061343
