Vis enkel innførsel

dc.contributor.authorPaulsen, Maria Lund
dc.contributor.authorRiisgård, Karen
dc.contributor.authorSt. John, Mike
dc.contributor.authorThingstad, T. Frede
dc.contributor.authorNielsen, Torkel Gissel
dc.date.accessioned2018-02-09T08:27:49Z
dc.date.available2018-02-09T08:27:49Z
dc.date.issued2017
dc.PublishedPaulsen ML, Riisgård, St. John M, Thingstad TF, Nielsen TG. Heterotrophic nanoflagellate grazing facilitates subarctic Atlantic spring bloom development. Aquatic Microbial Ecology. 2016;78(3):161-176eng
dc.identifier.issn0948-3055en_US
dc.identifier.issn1616-1564en_US
dc.identifier.urihttps://hdl.handle.net/1956/17357
dc.descriptionUnder embargo until: 2022-02-22
dc.description.abstractThe subarctic Atlantic phytoplankton spring bloom is one of the largest biological features of the ocean; however, processes initiating the bloom are still not well understood. We hypothesize that the microbial grazing food chain plays an important role in creating a pre-bloom condition with top-down control of small-sized phytoplankton, thus paving the way for a diatomdominated spring bloom. To assess the trophic role of protist grazers during the winter to spring transition, 3 experiments were performed using size-fractionated surface water from the Iceland Basin (March−April 2012). These experiments demonstrated heterotrophic nanoflagellates (HNF) grazing of picophytoplankton to be a key pathway, even though these are rarely considered as important phytoplankton grazers in high-latitude systems. The growth rate of HNF was significantly correlated to the biomass of picophytoplankton and was substantially higher than the growth of the larger microzooplankton (MZP), i.e. ciliates and dinoflagellates. During the first experiment, small phytoplankton dominated and overall protist grazing (HNF + MZP) was low. In the later experiments, MZP grazing on HNF became evident; however, MZP were not able to control the community of larger phytoplankton (>10 μm), which became more abundant. Our experiments thus support the hypothesis that pre-bloom conditions promote a build-up of large phytoplankton, i.e. diatoms. We found that the high growth rates of HNF together with the relaxed MZP grazing pressure allow HNF to respond rapidly to the early primary production by picophytoplankton and maintain a strong top-down control on these. We suggest that this succession may be an important mechanism that allows large diatoms, rather than picophytoplankton, to become the dominant primary producers during the subarctic Atlantic spring bloom.en_US
dc.language.isoengeng
dc.publisherInter-Researchen_US
dc.relation.ispartof<a href="http://hdl.handle.net/1956/17362" target="blank">Microbial dynamics in high latitude ecosystems. Responses to mixing, runoff and seasonal variation a rapidly changing environment</a>en_US
dc.subjectMicrobial food webeng
dc.subjectFractionation experimenteng
dc.subjectPre-bloomeng
dc.subjectBloom developmenteng
dc.subjectPicophytoplanktoneng
dc.subjectHeterotrophic nanoflagellateseng
dc.subjectMicrozooplanktoneng
dc.subjectTop-down controleng
dc.titleHeterotrophic nanoflagellate grazing facilitates subarctic Atlantic spring bloom developmenten_US
dc.typePeer reviewed
dc.typeJournal article
dc.date.updated2018-02-08T09:42:15Z
dc.description.versionpublishedVersionen_US
dc.rights.holderCopyright Inter-Research 2017en_US
dc.identifier.doihttps://doi.org/10.3354/ame01807
dc.identifier.cristin1441095
dc.source.journalAquatic Microbial Ecology


Tilhørende fil(er)

Thumbnail

Denne innførselen finnes i følgende samling(er)

Vis enkel innførsel