Influence of seawater density on pelagic carbonate production

Planktonic foraminifera are a critical component of global pelagic biogeochemistry, export fluxes, and seawater properties. Calcifying foraminifera cells are profoundly important to biogeochemistry also due to their mass and strong ballasting of particulate organic matter that drives the biological carbon pump and to carbon cycling because of the biochemistry of calcite formation that both removes carbon towards the geological record in the form of carbonate and also produces CO₂ for every molecule of CaCO₃ produced. My research shows that ocean density exerts a role on planktonic foraminifera biomineralization. Since foraminifera are non-motile plankton glacial/interglacial ocean density fluctuations may cause shell weight changes for buoyancy regulation if foraminifera tend to always maintain certain depths. This newly described mechanism may help to further elucidate the marine carbon cycle. The decreased plankton calcification needs that it foresees during warm periods of lighter waters would remove less alkalinity from the surface interglacial ocean thus leaving it capable to absorb more atmospheric carbon. Furthermore, it is found that foraminifera species calcification intensifies with depth habitat following the increase in water density, offering new hints about the control of the different ocean strata to the carbon cycle.