El microfitoplancton en los principales muelles de la Bahía de Cartagena, Caribe colombiano, vectores posibles de floraciones microalgales

Abstract

In order to evaluate the micro-plankton space-temporal changes in the bay of Cartagena, between March-November 2005, and to detect species with capacity of developing partially dangerous flowering, several sampling at different points of the bay were carried out determining their composition, abundance and the chlorophyll a concentration. A total of 124 species were found, distributed in 49 types and 18 families, besides 6 morpho-types and the presence of 10 structures of resistance. The greater relative abundances were observed in the group of central diatomeas followed by the pennales ones, standing out the species Skeletonema costatum and the types of Coscinodiscus, Chaetoceros, among others. The chlorophyll a concentrations reached a level of 44.79mg/m3. The cysts and hypno-cysts reached relative abundances between 0,01 and 56.13%, were the presence of species designated as potentially risky such as Asterionellopsis glacialis and Dinophysis caudata. The results show changes in the community structure, caused by variations in the water physical-chemical conditions of the Bay of Cartagena, standing out the marine species which have developed adaptations through time, being capable of surviving under tropical marine-estuary conditions, caused mainly by the continuous continental waters dumping in the Bay.