The aim of this study was to evaluate the influence of seasonal variation of environmental conditions on the structural attributes of the periphyton community on Eleocharis acutangula (Roxb.) Schult (Cyperaceae) in the littoral zone of Ninféias Lake, São Paulo, São Paulo State, Brazil. The spring and summer were characterized by higher values of macrophyte cover, phytoplankton chlorophyll a, light, and phosphorus availability in the water. Periphyton biomass and algal density were negatively correlated with macrophyte cover and phytoplankton chlorophyll a. The species composition, algal classes, and descriptors changed in seasonal scale. We concluded that periphyton community structure on Eleocharis acutangula was strongly influenced by macrophyte cover and phytoplankton biomass. Availability of nutrientsin the water seems to play a minor role in community organization. The responses of the structural attributes of the periphyton showed a strong interrelationship with macrophytes and phytoplankton, which should be better understood in shallow tropical reservoirs.
biomass; diversity; emergent macrophyte; species composition
