Variations in the Epiphytic Invertebrate Community Structure on Potamogeton Perfoliatus L. in Traunsee (Austria): Patchiness versus Impacts by Industrial Tailings

The epiphytic invertebrates found on Potamogeton perfoliatus L. in Traunsee, an oligotrophic Alpine lake in Austria, were investigated in August and October 1998 in order to study the impact of industrial tailings discharged into the lake. 113 taxa were found, 54 could be identified to the species level. Their total abundance varied between ca. 190,000 and 1,138,000 ind. m super(-2) lake bottom area. This epiphytic assemblage was dominated by Dreissena polymorpha and Sida crystallina, which resulted in a very low overall species diversity. Multivariate statistical analyses revealed significant differences in the community structure between three sites, each of them was located at a different distance from the site of industrial waste emission. These differences were interpreted as variations which reflect the patchiness within highly structured habitats rather than as being the result of the industrial pollution.