Cyanobacteria in Spanish reservoirs. How frequently are they toxic?

Abstract

In this paper we analyse the cyanobacterial occurrence in the Spanish reservoirs, using data obtained from published material or reports of several Spanish institutions. Our analysis shows that potentially toxic cyanobacteria are widespread in the Spanish reservoirs, dominating the phytoplankton community at least once during the study period in a high proportion of the investigated reservoirs (35-48%). The bibliographic data also show that in Europe and in the rest of the World more than 70% of the samples analysed from potentially toxic cyanobacteria were toxic. Extrapolating these data we can assume that a high proportion of the Spanish reservoirs (between 25 and 35 %) present a high probability of developing blooms of toxic cyanobacteria. Finally, the available data about the presence of cyanotoxins in different Spanish Basins show that cyanotoxins are present in all the analysed basins and occasionally show very high toxin concentrations. © Asociación Española de Limnología, Madrid.