Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 4 5 2007 10.5194/bg-4-853-2007 http://www.biogeosciences.net/4/853/2007/ http://www.biogeosciences.net/4/853/2007/bg-4-853-2007.html http://www.biogeosciences.net/4/853/2007/bg-4-853-2007.pdf 853 868 2007-10-16 Relationship between photosynthetic parameters and different proxies of phytoplankton biomass in the subtropical ocean Y. Huot huot@obs-vlfr.fr M. Babin F. Bruyant C. Grob M. S. Twardowski H. Claustre CNRS, Laboratoire d'Océanographie de Villefranche, 06230 Villefranche-sur-Mer, France; Université Pierre et Marie Curie-Paris 6, Laboratoire d'Océanographie de Villefranche, 06230 Villefranche-sur-Mer, France Dalhousie University, Department of Oceanography, 1355 Oxford Street, Halifax N.S. B3H 4J1, Canada WET Labs, Inc., Department of Research, 165 Dean Knauss Dr., Narragansett, RI 02882, USA Graduate Program in Oceanography, Department of Oceanography and Center for Oceanographic Research in the eastern South Pacific, University of Concepción, Casilla 160-C, Concepción, Chile Probably because it is a readily available ocean color product, almost all models of primary productivity use chlorophyll as their index of phytoplankton biomass. As other variables become more readily available, both from remote sensing and in situ autonomous platforms, we should ask if other indices of biomass might be preferable. Herein, we compare the accuracy of different proxies of phytoplankton biomass for estimating the maximum photosynthetic rate (Pmax) and the initial slope of the production versus irradiance (P vs. E) curve (α). 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