4. Periphyton community structure

The results of investigation of Lake Drūkšiai periphyton community are presented. Periphyton community parameters, such as periphyton abundance on its dominant substrate (common reed Phragmites communis) and a ratio of mineral and organic components, were estimated. The percentage of algal biomass in the community was calculated on the basis of chlorophyll content. The structure of periphyton algal communities: percentage of different divisions of algae in phytoperiphyton and dominant species of algae, was investigated. The species diversity of periphyton algae was estimated by widely used indices: Shannon’s diversity index, Simpson’s concentration index, Pielou’s evenness index, and Pantle–Buck saprobity index.