AUTHOR=Smyth Timothy , Moffat David , Tarran Glen , Sathyendranath Shubha , Ribalet Francois , Casey John 

TITLE=Determining drivers of phytoplankton carbon to chlorophyll ratio at Atlantic Basin scale

JOURNAL=Frontiers in Marine Science

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2023.1191216

DOI=10.3389/fmars.2023.1191216

ISSN=2296-7745

ABSTRACT=<p>We demonstrate the ability of flow cytometry to determine species specific cellular carbon and chlorophyll content <italic>in vivo</italic> by using laboratory cultures of phytoplankton encompassing a wide range of cell sizes. When applied to the large Atlantic Meridional Transect flow cytometry dataset, we reveal patterns in the species-specific phytoplankton carbon (C), chlorophyll (Chl) and C:Chl ratio. For <italic>Prochlorococcus</italic> the range of C:Chl is between 2 – 604; for <italic>Synechococcus</italic> 0.5 – 558. Using a Random Forest machine learning approach, we show that predictability of phytoplankton C:Chl, dominated by the prevalence of <italic>Prochlorococcus</italic>, is largely driven by silicate and nitrite concentration in the Atlantic Ocean.</p>