MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 448:23-37 (2012) - DOI: https://doi.org/10.3354/meps09480 Relationship between induced phytoplankton blooms and the structure and dynamics of the free-living heterotrophic bacterial community Itziar Lekunberri1,2,*, Thomas Lefort1, Cristina Romera-Castillo1, Clara Cardelús1, Montserrat Coll-Lladó1, Clara Ruiz-González1, Cèlia Marrasé1, Josep M. Gasol1,** 1Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar-CSIC, Barcelona, Catalunya, Spain 2Present address: Department of Marine Biology, University of Vienna, Althanstr. 14, 1090 Vienna, Austria Emails: *itzileku@hotmail.com, ** pepgasol@icm.cat ABSTRACT: Bacterial community activity and structure are thought to be directly or indirectly related to phytoplankton development and, in particular, to the phytoplankton species dominating specific algal blooms. To test this hypothesis, we performed a mesocosm experiment designed to generate blooms of different types of phytoplankton through the additions of silicate, urea and phosphorus to oligotrophic water from the Blanes Bay Microbial Observatory (NW Mediterranean). Over 10 d of incubation bacterial activity, bacterial abundance, nutrient composition and free-living bacterial community structure were monitored, as well as phytoplankton composition and the fluorescence characteristics of dissolved organic matter (DOM). While we found clear effects of the different nutrient additions on chlorophyll levels, bacterial production and the type of dominant DOM, bacterial abundance followed a similar pattern across different nutrient treatments, which deviated from that observed in the control. While phytoplankton composition in the treatment with added silicate evolved differently with respect to the other treatments, free-living bacterial community structure (as determined with DGGE) did not show conspicuous differences between treatments. Our results reveal that the changes in bacterial community composition were mostly due to the variation in grazing pressure with time, with a small contribution from changes in bottom-up nutrient supply mediated by the shifts in phytoplankton composition. KEY WORDS: Nutrients · Phytoplankton · Bacterial diversity · Mesocosms Full text in pdf format Supplementary material PreviousNextCite this article as: Lekunberri I, Lefort T, Romera-Castillo C, Cardelús C and others (2012) Relationship between induced phytoplankton blooms and the structure and dynamics of the free-living heterotrophic bacterial community. Mar Ecol Prog Ser 448:23-37. https://doi.org/10.3354/meps09480 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 448. Online publication date: February 23, 2012 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2012 Inter-Research.