When iron was added , both Fe and Si became critical limiting nutrients to phytoplankton frowth at OSP (Denman et al., 2006; Ianson et al., in prep). ###>Quand on ajoutait du fer, Ã la fois le Fe et la Si devenaient des nutriments limitants critiques de la croissance du phytoplancton Ã la SOP (Denman et al., 2006; Ianson et al., en prÃ©p).