Some observations on marine phytoplankton kinetics: 2. the effect of nitrate and ammonium concentrations on the growth and uptake rates of the natural population of Ubatuba region, SP (23ºS, 045ºW)

Abstract

The phytoplankton Ks anã Vmax as a function of ammonium and nitrate concentrations were determined. The growth rate was estimated from measurements on synthesized chlorophyll-α and the cell number in the. culture media. The uptake rate was determined as to the consumption of ammonium and nitrate after the nutrients depletion from culture media.Foram determinadas a Ks e a Vmax do fi toplancton natural, em função da concen tração de amonia e nitrato. A velocida de de crescimento foi determinada como clorofila-a sintetizada e numero de cé lulas no meio de cultura. A velocidade de assimilação foi determinada como o consumo de amonia e nitrato depois do esgotamento desses nutrientes do meio de cultura.

Keywords

• Fitoplâncton
• Cinética
• Nitratos
• Amonio
• Crescimento
• Clorofilas
• Nutrientes minerais
• Fatores limitantes
• Contagem de célula
• Fluorescencia
• Phaeodactylum tricornutum
• Ubatuba
• SP
• Phytopiankton
• Kinetics
• Nitrates
• Ammonium
• Growth
• Chlorophylls
• Nutrients (mineral)
• Limiting factors
• Cell counting
• Fluorescence
• Phaeodactylum tricornutum
• Ubatuba
• SP