Abundancia y distribución de ciliados pláncticos en el lago Catemaco, en temporada de secas

Abstract

Abstract. The ecological study of planktonic ciliates in Mexican lakes is in its initial stages. Lake Catemaco has a historical, social and economic major role. In this context the composition, abundance, and distribution of ciliates were studied. Oligotrichs were dominant and total abundance of ciliates varied between 2 and 57 cel ml1 . The spatial and temporal variability in the abundance of cilia tes was analyzed and relationships among environmental variables and ciliates abundance were characterized using a principal component analysis. No significant differences between collection sites or between surface and bottom depths were found, but between month and collection site combined, which reflects the polymixis effects. Reduced N:P atomic ratios, high chlorophyll concentrations and turbidity, cyanobacteria dominance and ciliate abundance allow characterizing the lake during the dry season as one intermediate between meso and eutrophic lakes.