Gamma A is a widespread non-cyanobacterial diazotroph that plays a crucial role in marine ecosystems, but its controlling factors are still largely unknown. This study, for the  first time, quantified microzooplankton grazing on Gamma A and revealed the significance of grazing pressure on Gamma A distribution around the Kuroshio region. It highlights the importance of top-down controls on Gamma A abundance and the associated nitrogen cycle.

We studied the effect of addition of carbonate minerals on coastal sediments. We carried out laboratory experiments to quantify the dissolution kinetics and integrated these observations into a numerical model that describes biogeochemical cycling in surficial sediments. Using the model, we demonstrate the buffering effect of the mineral additions and their duration. We quantify the effect under different environmental conditions and assess the potential for increased atmospheric CO₂ uptake.