titoli, abstracts, parole chiave >>>
Natural bacterioplankton assemblage composition during blooms of Alexandriumspp. (Dinophyceae) in NW Mediterranean coastal waters

Garcés, Esther and Vila, Magda and Reñé, Albert and Alonso-Sáez, Laura and Anglès, Silvia and Lugliè, Antonella Gesuina Laura and Masó, Mercedes and Gasol, Josep M. (2007) Natural bacterioplankton assemblage composition during blooms of Alexandriumspp. (Dinophyceae) in NW Mediterranean coastal waters. Aquatic Microbial Ecology, Vol. 46 (1), p. 55-70. eISSN 1616-1564. Article.

Full text not available from this repository.

DOI: 10.3354/ame046055


We characterised the spatial and temporal variation in the bacterioplankton assemblage composition during bloom events of different Alexandriumspecies (Dinophyceae) in the littoral of the NW Mediterranean Sea by means of catalysed reporter deposition fluorescence in situhybridisation with oligonucleotide probes (CARD-FISH). We studied several Alexandriumblooms through their seasonal development (at La Fosca beach) or in their spatial variability (in Arenys Harbour and Olbia Bay), and we complemented these observations by describing the composition of the bacterial assemblage associated with cultures of Alexandriumspecies isolated from the same sites. Our studies on natural bacterioplankton assemblages identified the Bacteroideteslineage and the Alphaproteobac- teria as the dominating components during the studied blooms of Alexandrium. Alphaproteobacteria dominated in the La Fosca and Olbia blooms, while bacteria belonging to the Bacteroidetes were abundant in the development phase of the La Fosca beach bloom and in the winter Arenys bloom. Gammaproteobacteria contributed in low proportions without significant changes through the different bloom phases at La Fosca beach and in Olbia Bay, but were more abundant in Arenys Harbour. While the absolute bacterial abundances in the spatial study of Olbia Bay covaried with the Alexan- drium densities, there were no spatial changes in the bacterioplankton assemblage composition. Alteromonas-like organisms were never an important fraction of the assemblage, but Roseobacter dominated Alphaproteobacteriain Arenys Harbour. Furthermore, the bacterioplankton assemblages associated with Alexandrium spp. cultures were very different from the natural bacterial assemblages during blooms of the same species. We conclude that the presence of a given harmful algal bloom species during a bloom will not always necessarily be accompanied by the same bacterial assemblage structure, and studies done with dinoflagellate cultures may only reflect the bacteria capable of growing under laboratory conditions, with little resemblance to what occurs under natural conditions.

Item Type:Article
ID Code:1663
Uncontrolled Keywords:FISH, Dinoflagellates, HAB, Alexandrium, Roseobacter, Alteromonas
Subjects:Area 05 - Scienze biologiche > BIO/07 Ecologia
Divisions:001 Università di Sassari > 01 Dipartimenti > Scienze botaniche, ecologiche e geologiche
Deposited On:18 Aug 2009 10:05

I documenti depositati in UnissResearch sono protetti dalle leggi che regolano il diritto d'autore

Repository Staff Only: item control page