Phytoplankton distribution and photosynthesis as related to tidal dynamics in the Babitonga Bay, Brazil

STRAUCH, S. M.; ERZINGER, G. S.; MACHADO, C. K.; MARENZI, A. W.C.; VILLAFAÑE, V. E.; HELBLING, E. W.

Camboriu

Congreso; XIV Congreso Latinoamericano de Ciencias del Mar; 2011

The aim of this study was to determine the effects of tidal dynamics on phytoplankton distribution and photosynthesis in Babitonga Bay, Brazil. Physical, chemical and biological variables were measured on a sampling grid during winter, spring and late summer. In the study area stratification was mainly caused by a salinity gradient, with a distinct salt wedge during the flood and rather homogeneous during the ebb. Phytoplankton distribution was estimated by chlorophyll a measurements as well as from cell determination and counting. The influence of mixing and of solar radiation on photosynthesis was determined with a pulse amplitude modulated (PAM) fluorometer. Overall, our results show a tidal-modulated distribution of phytoplankton and inhibition of photosynthesis related to mixing.