Throughout my scientific career I have focused on the study of planktonic microorganisms, mainly phytoplankton. I have addressed the ecological characterization of these microorganisms based on their size-distribution, chemical composition and taxonomy. Within my current interests are the long-term spatio-temporal dynamics of phytoplankton assemblages in relation to physico-chemical variables and the morphological and molecular characterization of the planktonic diatom genus Chaetoceros.