Calculating carbon biomass of Phaeocystis sp. from microscopic observations

摘要: Conversion factors for calculating carbon biomass ofPhaeocystis sp. colonies and free-living cells were determined from microscopic observations chemical analysis conducted on cultured naturalPhaeocystis populations originating the Southern Bight of North Sea in 1986 1987. They allow calculation, terms biomass, different forms that succeed each other when population is growing, basis observations. The latter include enumerations (flagellated non-motile) colonies, as well colonial biovolume measurement. Specific application to natural Dutch coastal waters during spring shows more than 90% under form, most it exceeding grazing characteristics current zooplankton at this period year. Detailed seasonal changes addition size greatly increases course flowering, reaching sizes high 1 mm diameter top bloom nutrients are depleted. Physiologically corresponds an enhanced synthesis mucilaginous substances, with decrease available leading increasing contribution matrix total bloom. Carbon content therefore varies their size, ranging 0.3 1430 ngC colony−1.