His main scientific interest is on the dynamics of marine microbes and plankton, especially from a biogeochemical perspective. He has worked on the effects of temperature and turbulence on plankton, protistan grazing, the dynamics of nutrients in coastal areas and the effects of atmospheric deposition in marine systems. He has developed laboratory systems to study plankton under controlled turbulent conditions. He is also working on water use and effects in coastal areas, climate change effects on marine production, and is starting to work on marine plastic pollution and the relationship between planetary and human health.