INFLUENCE OF WATER STABILITY ON THE VERTICAL STRUCTURE OF A PHYTOPLANKTON COMMUNITY

The vertical distribution of the phytoplankton community in association with water column stability was examined for 1 year in an inshore area of the Southern Aegean Sea. An analysis of variance model (split-plot design) was applied to evaluate the variations in the vertical profile of diatoms, flagellates and coccolithophores. When either weak stratification or mixing conditions prevailed, diatoms in general were uniformly distributed throughout the water column while flagellates and coccolithophores appeared occasionally stratified. During the strong stratification period, all taxa demonstrated significant variations in abundance between depths in most cases. However, none of these taxa was confined to a single depth stratum during either the water mixing or the stratification period, but were all present at all depths during all seasons. The results demonstrate clearly that the parameter taxon" is an important component in ecological observations on the vertical distribution of phytoplankton. © 1979 Springer-Verlag."