Show simple item record

dc.contributor.authorMoran, Xose Anxelu G.
dc.contributor.authorCalvo-Diaz, Alejandra
dc.contributor.authorDucklow, Hugh W.
dc.date.accessioned2011-05-04T16:11:41Z
dc.date.available2011-05-04T16:11:41Z
dc.date.issued2010-01-20
dc.identifier.citationAquatic Microbial Ecology 58 (2010): 229-239en_US
dc.identifier.urihttp://hdl.handle.net/1912/4544
dc.descriptionAuthor Posting. © Inter-Research, 2010. This article is posted here by permission of Inter-Research for personal use, not for redistribution. The definitive version was published in Aquatic Microbial Ecology 58 (2010): 229-239, doi:10.3354/ame01374.en_US
dc.description.abstractThe regulation of heterotrophic bacterial growth by resource supply (bottom-up control) was temperature-dependent in our analysis of data obtained during 2006 in the euphotic layer of the southern Bay of Biscay (NE Atlantic) continental shelf. The dataset was split into 2 subgroups using 16°C as the boundary between warm and cool waters based on differences in associated physico-chemical conditions, e.g. inorganic nutrient limitation at higher temperatures. The linear regressions between bacterial biomass (BB) and leucine incorporation rates (LIR) were significantly positive in both temperature regimes, thus indicating similar total bottom-up control, albeit with a slightly higher slope in warm waters (0.33 vs. 0.22). However, the relationship of LIR with phytoplankton biomass (chl a), which is an indicator of bottom-up control that is mediated by phytoplankton, was only significant in waters below 16°C. The analysis of bimonthly variations in the BB-LIR and LIR-chl a correlations indicated that the strength of total bottom-up control significantly increased while the role of phytoplankton in supplying DOM to bacteria diminished with mean temperatures over the 12 to 19°C range, suggesting a seasonal switch in the major source of substrates used by bacteria. We show that the abundance of cells with relatively high nucleic acid content (HNA), which are hypothesized to be the most active ones, was positively associated with bacterial production and specific growth rates in cool but not in warm conditions. These results suggest that HNA bacteria are good predictors of bulk activity and production in temperate ecosystems only when the community relies principally on phytoplankton substrates for growth and metabolism.en_US
dc.description.sponsorshipX.A.G.M. was partially supported by a sabbatical grant at the MBL from the Spanish Ministry of Education and Science (MEC) and A.C.-D. received an FPI research training predoctoral fellowhip. This work was supported by the time-series project RADIALES from the Instituto Espanol de Oceanografia (IEO).en_US
dc.format.mimetypeapplication/pdf
dc.language.isoenen_US
dc.publisherInter-Researchen_US
dc.relation.urihttp://dx.doi.org/10.3354/ame01374
dc.subjectBacterioplanktonen_US
dc.subjectBottom-up controlen_US
dc.subjectTemperatureen_US
dc.subjectBacterial biomassen_US
dc.subjectBacterial activityen_US
dc.subjectPhytoplanktonen_US
dc.subjectCoastal watersen_US
dc.titleTotal and phytoplankton mediated bottom-up control of bacterioplankton change with temperature in NE Atlantic shelf watersen_US
dc.typeArticleen_US
dc.identifier.doi10.3354/ame01374


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record