Some observations on the kinetics of marine phytoplankton: 1 The influence or nitrate and ammonium concentrations on the growth velocity and assimilation of these nutrients in the diatom Phaeodactylum tricornutum (Bohlin) . Bol. Inst. Oceanogr. 1982;31(2):13-27. doi:10.1590/S1679-87591982000200004