Colonisation and growth of epiphytic algal communities on Potamogeton perfoliatus under two different light regimes

Abstract

The composition and distribution of epiphytic algae on Potamogeton perfoliatus were studied in a controlled laboratory environment over 84 days under two light conditions. The study was based on a 2 × 2 factorial design with two light conditions (high and low, 200 and 80 μE m^–2 s^–1) and two different plant parts (apical and basal). In both light conditions, the community consisted of 18 taxa (under nine genera) of Bacillariophyceae. Amphora lineolata, Cocconeis placentula, and Diatoma hiemale were the most common and abundant species. The total algal density was significantly higher in the high light condition and on the basal plant part than in the low light condition and on the apical plant part. At termination of the experiment, basal plant parts exhibited a more uniform crust of epiphytic algae consisting of c. 95% C. placentula whereas the apical plant parts expressed a more mosaic community (under both light conditions).

Keywords:

• algal density
• community
• species richness
• abundance

Notes

Author for correspondence.