Composition of macroalgal epiphytic assamblages on ...

[P054] Composition of macroalgal epiphytic assamblages on habitat- forming macroalgae Fucus vesiculosus and Furcellaria lumbricalis in the Baltic sea T. Paalme*, P. Kersen, R. Treier Estonian Marine Institute University of Tartu, Estonia A comparison of the species composition of macroalgal epiphytic assemblages growing on Fucus vesiculosus (PHAEOPHYTA) and Furcellaria lumbricalis (RHODOPHYTA) – widely distributed canopy-forming macroalgal species in benthic communities of the Baltic Sea, was carried out with algal material collected during the vegetation period (April-October 2011) from three different locations (Kakumäe, Kõiguste and Küdema Bays) in Estonian coastal sea. Non parametric multivariate analysis of variance (PERMANOVA) was used to examine differences in the patterns of variation in composition of macroalgal epiphytic assamblages between basibiont species, sampling sites and season. The similarities percentages analysis (SIMPER) was used to identify which species were responsible for the similarity within and the dissimilarity between sampling sites during different seasons. Results indicated significant differences between epiphytic assemblages associated with F. vesiculosus and F. lumbricalis and considerable temporal and spatial variation in the species composition of epiphytic assemblages on both host species. In total 14 macroalgal species was found in epiphytic assemblages on F. vesiculosus and F. lumbricalis. Most common species on both host species were Pilayella littoralis (PHAEOPHYTA), Ceramium tenuicorne and Phyllophora truncata (RHODOPHYTA), while the abundance (biomass) of these macroalgae was dependent on basibiont species and varied between seasons and locations. Keywords: Macroalgal epiphytes, Fucus vesiculosus, Furcellaria lumbricalis, the Baltis Sea