Resumen

GONZALEZ, Ernesto J; ORTAZ, Mario; PENAHERRERA, Carlos  y  MATOS, María L.. Fitoplancton de un embalse tropical hipereutrófico (Pao-Cachinche, Venezuela): abundancia, biomasa y producción primaria. INCI [online]. 2004, vol.29, n.10, pp.548-555. ISSN 0378-1844.

Phytoplankton abundance, biomass and primary production were estimated at two localities in the Pao-Cachinche reservoir (Venezuela). The reservoir receives tributaries with large amounts of nutrients from wastewater and from neighboring pig and poultry farms. Mean phytoplankton abundance and biomass were 86.1·10⁹ cells·m^-2 and 92.1mg chl-a·m^-2, respectively. Cyanobacteria accounted for more than 75% of total phytoplankton. Gross primary production ranged between 456 and 6816mg C·m^-2·d^-1, which can be considered as high. Pao-Cachinche reservoir can be considered as hypereutrophic, due to the high level of nutrients and biological productivity. Nutrient input, algal self-shade, flushing of cells and treatment with chemical compounds were responsible for phytoplankton fluctuations in this reservoir.

Palabras clave : Embalse Tropical; Eutrofización; Fitoplancton; Venezuela.