Aquatic macroinvertebrate community structure of a Nymphoides peltata-dominated and macrophyte-free site in an oxbow lake

The aquatic fauna in two freshwater biotopes, namely a Nymphoides peltata-dominated site and a macrophyte-free site, were studied quantitatively in a shallow oxbow lake of the river Waal. Water, sediment and macrophyte samples were analysed. Species richness, densities, and biomass of macro-invertebrates were considerably higher in the biotope with macrophytes. Sediment-dwelling fauna constituted a quantitatively important component in the Nymphoides-dominated site. It seems that macrophyte detritus plays an important role in determining the trophic structure of the macro-invertebrate community