Accumulation of the surf diatom Anaulus sp. at Navegantes Beach, Southern Brazil: An Ecological Approach

Abstract

This paper describes an accumulation process of the diatom Anaulus sp. in the surfzone of Navegantes beach (Santa Catarina, Brazil). Related environmental factors were analised and trophic importance was discussed. The results showed that such periodical events, associated to the incidence of cold fronts and related increasing of wave energy on the surf zone, set a high vegetable biomass to pelagic and benthic food chains. The grazing and predation by zooplankton (experimentally indicated), as well as the concentration of zooplankton groups and fishes on the accumulations, indicate lhe occurrence of intense trophic fluxes during the events. These facts suggest that Navegantes beach, besides many sandy beaches of the world, could be also considered a very productive coastal ecosystem.