Vis enkel innførsel

dc.contributor.authorTsagaraki, Tatiana Margo
dc.contributor.authorPree, Bernadette
dc.contributor.authorLeiknes, Øystein
dc.contributor.authorLarsen, Aud
dc.contributor.authorBratbak, Gunnar
dc.contributor.authorØvreås, Lise
dc.contributor.authorEgge, Jorun Karin
dc.contributor.authorSpanek, Roman
dc.contributor.authorPaulsen, Maria Lund
dc.contributor.authorOlsen, Yngvar
dc.contributor.authorVadstein, Olav
dc.contributor.authorThingstad, T. Frede
dc.PublishedTsagaraki T.M., Pree B, Leiknes Ø, Larsen A, Bratbak G, Øvreås L, Egge JK, Spanek R, Paulsen ML, Olsen Y, Vadstein O, Thingstad TF. Bacterial community composition responds to changes in copepod abundance and alters ecosystem function in an Arctic mesocosm study. The ISME Journal. 2018;12:2694–2705eng
dc.description.abstractCombining a minimum food web model with Arctic microbial community dynamics, we have suggested that top-down control by copepods can affect the food web down to bacterial consumption of organic carbon. Pursuing this hypothesis further, we used the minimum model to design and analyse a mesocosm experiment, studying the effect of high (+Z) and low (-Z) copepod density on resource allocation, along an organic-C addition gradient. In the Arctic, both effects are plausible due to changes in advection patterns (affecting copepods) and meltwater inputs (affecting carbon). The model predicts a trophic cascade from copepods via ciliates to flagellates, which was confirmed experimentally. Auto- and heterotrophic flagellates affect bacterial growth rate and abundance via competition for mineral nutrients and predation, respectively. In +Z, the model predicts low bacterial abundance and activity, and little response to glucose; as opposed to clear glucose consumption effects in –Z. We observed a more resilient bacterial response to high copepods and demonstrate this was due to changes in bacterial community equitability. Species able to use glucose to improve their competitive and/or defensive properties, became predominant. The observed shift from a SAR11-to a Psychromonodaceae – dominated community suggests the latter was pivotal in this modification of ecosystem function. We argue that this group used glucose to improve its defensive or its competitive abilities (or both). Adding such flexibility in bacterial traits to the model, we show how it creates the observed resilience to top-down manipulations observed in our experiment.en_US
dc.publisherSpringer Natureen_US
dc.rightsAttribution CC BYeng
dc.titleBacterial community composition responds to changes in copepod abundance and alters ecosystem function in an Arctic mesocosm studyen_US
dc.typePeer reviewed
dc.typeJournal article
dc.rights.holderCopyright 2018 The Authorsen_US
dc.source.journalThe ISME Journal
dc.relation.projectNorges forskningsråd: 225956
dc.relation.projectEC/FP7: 603773

Tilhørende fil(er)


Denne innførselen finnes i følgende samling(er)

Vis enkel innførsel

Attribution CC BY
Med mindre annet er angitt, så er denne innførselen lisensiert som Attribution CC BY