No sign of denitrification in a Baltic Sea cyanobacterial bloom

Hietanen, Susanna; Moisander, Pia H.; Kuparinen, Jorma; Tuominen, Liisa

doi:10.3354/meps242073

Cited by 13 publications

(7 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We believe that N, fixed by diazotrophs, became exceedingly available to the heterotrophic bacteria and confounded the effect of mineral nutrient limitation. This indicates that N 2 -fixing cyanobacteria are an immediate source of bioavailable N in the Baltic Sea, as suggested by Hietanen et al (2002).…”

Section: Bacteria Interacting With Phytoplanktonsupporting

confidence: 54%

Labile carbon supplement induces growth of filamentous bacteria in the Baltic Sea

Tammert¹,

Lignell²,

Kisand³

et al. 2012

Aquat. Biol.

View full text Add to dashboard Cite

A 3 wk experiment with 9 mesocosms (51 m 3 ) was carried out at a coastal site of the brackish northwest Gulf of Finland (Baltic Sea) to study the effects of nutrient limitation and labile carbon (C) amendment on the plankton community. A 5 d period with daily inorganic nitrogen (N) and phosphorus (P) additions boosted algal biomass increase and the demand for mineral nutrients. In the following 2 wk, the supply of 1 nutrient was cut, while keeping or increasing the other, thus inducing a gradient of nutrient-limitation regimes. Labile organic C (glucose) was added to increase bacterial growth and induce mineral nutrient competition between bacteria and algae. Here we report the effects of the treatments on bacterial abundance, production, and community composition. Addition of labile organic C led to a significant increase (p < 0.001) in the biomass of large filamentous bacteria and in bacterial productivity but not in the biomass of small coccoid bacteria. Addition of inorganic N and P did not have any clear-cut effect on bacterioplankton. Our results suggest that bacterial assemblages have the capacity to respond to enhanced substrate availability, and that glucose strongly enhances the development of filamentous bacteria, with implications for food-web structure, biodiversity, and biogeochemistry.

show abstract

Section: Bacteria Interacting With Phytoplanktonsupporting

confidence: 54%

Labile carbon supplement induces growth of filamentous bacteria in the Baltic Sea

Tammert¹,

Lignell²,

Kisand³

et al. 2012

Aquat. Biol.

View full text Add to dashboard Cite

show abstract

“…Interestingly, this group encompasses bacteria involved in the nitrification (ammonia oxidation activity), one of the key steps for nitrogen recycling. The presence of this specific functional N-recycling group has already been highlighted in several studies, but only associated with N 2 -fixing cyanobacteria and during marine blooms and in the Baltic Sea for example, where no nitrification activity could be detected [ 57 , 58 ]. More recently, Ploug et al [ 18 , 59 ] have shown in the Baltic Sea that Aphanizomenon sp .…”

Section: Discussionmentioning

confidence: 99%

Structural Diversity of Bacterial Communities Associated with Bloom-Forming Freshwater Cyanobacteria Differs According to the Cyanobacterial Genus

et al. 2015

View full text Add to dashboard Cite

The factors and processes driving cyanobacterial blooms in eutrophic freshwater ecosystems have been extensively studied in the past decade. A growing number of these studies concern the direct or indirect interactions between cyanobacteria and heterotrophic bacteria. The presence of bacteria that are directly attached or immediately adjacent to cyanobacterial cells suggests that intense nutrient exchanges occur between these microorganisms. In order to determine if there is a specific association between cyanobacteria and bacteria, we compared the bacterial community composition during two cyanobacteria blooms of Anabaena (filamentous and N2-fixing) and Microcystis (colonial and non-N2 fixing) that occurred successively within the same lake. Using high-throughput sequencing, we revealed a clear distinction between associated and free-living communities and between cyanobacterial genera. The interactions between cyanobacteria and bacteria appeared to be based on dissolved organic matter degradation and on N recycling, both for N2-fixing and non N2-fixing cyanobacteria. Thus, the genus and potentially the species of cyanobacteria and its metabolic capacities appeared to select for the bacterial community in the phycosphere.

show abstract

“…During a light-dark cycle new organic matter is synthesized during daytime. Anoxic conditions have long been suspected to occur within cyanobacterial colonies (Pearl and Bebout, 1988;Hietanen et al 2002). This study shows that anoxic conditions potentially occur within colonies 41 mm in the Baltic Sea (Figure 7b).…”

Section: Discussionmentioning

confidence: 81%

Carbon, nitrogen and O2 fluxes associated with the cyanobacterium Nodularia spumigena in the Baltic Sea

et al. 2011

View full text Add to dashboard Cite

Photosynthesis, respiration, N 2 fixation and ammonium release were studied directly in Nodularia spumigena during a bloom in the Baltic Sea using a combination of microsensors, stable isotope tracer experiments combined with nanoscale secondary ion mass spectrometry (nanoSIMS) and fluorometry. Cell-specific net C-and N 2 -fixation rates by N. spumigena were 81.6±6.7 and 11.4 ± 0.9 fmol N per cell per h, respectively. During light, the net C:N fixation ratio was 8.0 ± 0.8. During darkness, carbon fixation was not detectable, but N 2 fixation was 5.4 ± 0.4 fmol N per cell per h. Net photosynthesis varied between 0.34 and 250 nmol O 2 h À1 in colonies with diameters ranging between 0.13 and 5.0 mm, and it reached the theoretical upper limit set by diffusion of dissolved inorganic carbon to colonies (41 mm). Dark respiration of the same colonies varied between 0.038 and 87 nmol O 2 h À1 , and it reached the limit set by O 2 diffusion from the surrounding water to colonies (41 mm). N 2 fixation associated with N. spumigena colonies (41 mm) comprised on average 18% of the total N 2 fixation in the bulk water. Net NH 4 þ release in colonies equaled 8-33% of the estimated gross N 2 fixation during photosynthesis. NH 4 þ concentrations within light-exposed colonies, modeled from measured net NH 4 þ release rates, were 60-fold higher than that of the bulk. Hence, N. spumigena colonies comprise highly productive microenvironments and an attractive NH 4 þ microenvironment to be utilized by other (micro)organisms in the Baltic Sea where dissolved inorganic nitrogen is limiting growth.

show abstract

No sign of denitrification in a Baltic Sea cyanobacterial bloom

Cited by 13 publications

References 48 publications

Labile carbon supplement induces growth of filamentous bacteria in the Baltic Sea

Labile carbon supplement induces growth of filamentous bacteria in the Baltic Sea

Structural Diversity of Bacterial Communities Associated with Bloom-Forming Freshwater Cyanobacteria Differs According to the Cyanobacterial Genus

Carbon, nitrogen and O2 fluxes associated with the cyanobacterium Nodularia spumigena in the Baltic Sea

Contact Info

Product

Resources

About