The trophic role and impact of plankton ciliates in the microbial web structure of a tropical polymictic lake dominated by filamentous cyanobacteria

Abstract

The recent interest in the plankton structures and dynamics in tropical and subtropical lakes has revealed important trends that set these lakes apart from temperate lakes, and one of the main differences is ); however, significant differences were observed between seasons for both variables. Nano-sized filamentous cyanobacteria were the most abundant component of the plankton, and their abundance was assessed through epifluorescence microscopy counts. The autotrophic and heterotrophic picoplankton abundance was measured through epifluorescence, and their abundance and biomass were higher at the study site relative to other shallow freshwater ecosystems. The total ciliate biomass distribution patterns were similar to those of filamentous cyanobacteria and autotrophic or heterotrophic picoplankton, although the nanociliate biomasses peaked when the picoplankton and filamentous cyanobacteria were least abundant. The consequences of this increased importance of ciliates on the structure of the plankton at Lake Catemaco will be discussed along with the probable causes.

Caracterización de la variación morfológica de Cyanotetras (Cyanobacteria) en el Lago de Catemaco Veracruz, México

“…No se conocen con exactitud las condiciones óptimas para el crecimiento de C. crucigenielloides y C. aerotopa, especies poco frecuentes en sistemas eutróficos. Si bien las aguas residuales crudas de la ciudad de Catemaco no se descargan en el lago, las fuertes lluvias provocan el desborde del sistema de alcantarillado causando el enriquecimiento de sus aguas (Esquivel et al, 2009), provocando que el sistema pase de mesotrófico a eutrófico (Esquivel et al, 2016). C. crucigenielloides var.…”