Cytosense pleasure! Photos: Lennart Bach, GEOMAR

For seven weeks we have been fighting with the rough conditions of the Swedish winter to keep our mesocosm system alive. Now, after re-starting the experiment we hope, for the second time, to be able to do what we are here for – science. For the next weeks we expect sky rocketing diatom cell numbers followed by massive downward flux of organic carbon. Whether this regular pattern of the natural spring succession will change under ocean acidification is one of the key questions of this year´s mesocosm campaign.
In order not to miss the diatom party we invested in a imaging flow cytometer made by our favorite football vice world champions from the Netherlands. The Cytosense is quite an attraction as it not only provides data on the fluorescence signal of individual particles (as does every flow cytometer) but also provides pictures! So we can assign the clusters found in the scatter plots of the flow cytometer to distinct species. I admit this sounds nerdy, but being able to do that is a great satisfaction for phytoplankton loving people like we are!

Chain-forming diatoms already showed up in deeper water masses of the Fjord. Hopefully, the massive swarm of copepods,1 mm sized swimming animals that feed on diatoms, leave some for the flow cytometer. We deserve a bloom after all that struggle!

Detection of the chain-forming diatom “Skeletonema”

By Lennart T. Bach