Aquatic Invertebrates Associated with the Water-Hyacinth (Eichhornia crassipes) in an Eutrophic Reservoir in Tropical Brazil

Abstract

Abstract Quantitative samples of the aquatic invertebrate fauna associated to water-hyacinth (Eichhornia crassipes) vegetation were taken in an eutrophicated reservoir in southeastern Brazil. The assemblage was dominated by detritivores, most frequently oligochaetes, probably due to the large amount of sediment and detritus retained in the roots. Multivariate analysis (PCA and Canonical Correlation) suggested that, while some environmental variables were important to the dynamics of the system, biological interactions with the prosobranchiad snail Melanoides tuberculata could explain abundance patterns between sample sites.