Open AccessInfluence of oyster culture on biogeochemistry and bacterial community structure at the sediment–water interface
Author(s) -
Azandégbé Afi,
Poly Franck,
AndrieuxLoyer Françoise,
Kérouel Roger,
Philippon Xavier,
Nicolas JeanLouis
Publication year - 2012
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.2012.01410.x
Subject(s) - oyster , biology , sulfide , sediment , environmental chemistry , biogeochemical cycle , biogeochemistry , organic matter , mesocosm , community structure , ecology , ostreidae , ecosystem , fishery , shellfish , aquatic animal , chemistry , paleontology , organic chemistry , fish <actinopterygii>
Bacterial community structure and some biogeochemical parameters were studied in the sediment of two P acific oyster farming sites, A ber B enoît ( AB ) and R ivière d' A uray ( RA ) in B rittany ( F rance), to examine the ecological impact of oysters and to evaluate the emission of sulfide and ammonia from sediment. At AB , the organic matter accumulated in the sediment beneath the oyster tables was rapidly mineralized, with strong fluxes of ammonia and sulfide that reached 1014 and 215 μmol m −2 h −1 , respectively, in J une 2007. At RA , the fluxes were about half as strong on average and better distributed through the year. The ammonia and sulfide concentrations in the overlying water never reached levels that would be toxic to oysters in either site, nor did hypoxia occur. Total culturable bacteria ( TCB ) varied greatly according to the temperature: from 1.6 × 10 4 to 9.4 × 10 7 cell g −1 sediment. Inversely, the bacterial community structure remained surprising stable through the seasons, marginally influenced by the presence of oysters and by temperature. Bacterial communities appeared to be characteristic of the sites, with only one common phylotype, V ibrio aestuarianus , a potential oyster pathogen. These data refine the hypothesis of seawater toxicity to oysters because of ammonia and sulfide fluxes and show that the measured environmental factors had only a weak influence on bacterial community structure.