Year: 2005
Type: article
Abstract: AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 41:261-270 (2005) - doi:10.3354/ame041261 Effects of the colonial cyanobacterium Trichodesmium spp. on bacterial activity Florent Renaud1,2, Olivier Pringault1, Emma Rochelle-Newall1,* 1Centre IRD Noumea, BP A5, Promenade Roger Laroque, 98848 Nouméa Cedex, New Caledonia2Present address: International Atomic Energy Agency, Marine Environment Laboratory (IAEA-MEL), 4 Quai Antoine 1er, 98000 Monaco, Principality of Monaco *Corresponding author. Email: [email protected] ABSTRACT: We measured rates of particulate and dissolved primary production (DOCp) as well as bacterial production (BP) in order to determine the effect of freshly produced photosynthates onheterotrophic bacteria. During a 1 mo study carried out on samples from the southwestern lagoon of New Caledonia, we observed 2 different phytoplanktonic communities. The first was a mixed community, dominated by diatoms and with a low abundance of Trichodesmium spp. (10% total phytoplankton cells) and the second community was dominated by Trichodesmium spp. (up to 98% total phytoplankton cells). Chlorophyll a normalised total (particulate + dissolved) primary production rates were twice as high in the mixed community compared to the Trichodesmium spp. dominated community. The percentage of extracellular release (PER), calculated as the percentage of DOCp divided by total primary production (TOCp), reached 8% in the mixed community; in contrast, rates were much lower in the Trichodesmium spp. community and remained close to 1%. In terms of BP, activities were higher in the mixed community and were generally higher in light incubations than in the dark. In contrast, in the Trichodesmium spp. dominated community, bacterial activity was much lower and decreased with increasing Trichodesmium spp. abundance. This decrease in bacterial activity could not be explained by a decrease in bacterial abundance. This suggests that the proportion of active bacteria was much lower during the Trichodesmium spp. bloom. KEY WORDS: Dissolved primary production · Bacterialphytoplankton coupling · Bacterial production Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 41, No. 3. Online publication date: December 23, 2005 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2005 Inter-Research.
Source: Aquatic Microbial Ecology
DOI: 10.3354/ame041261
Authors: F Renaud, O Pringault, E Rochelle-Newall
Language: English
Subfield: Oceanography
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Life below water
Open Access status: bronze
OpenAlex ID: W2036664922