In particular, dominance may intensify intraspecific interactions for the dominant species, negatively influencing S. muticum performance at low evenness. It has been suggested that the magnitude of energy transferred to seaweed from a moving water mass depends on its size and shape (Norton 1991). Accordingly, after taking into consideration the biomass of the invader, the overall results were different, revealing

biomass dependent effects (Emmerson and Raffaelli 2000, Tait and Schiel 2011). After normalizing by biomass, the efficiency of macroalgal assemblages was associated with effects of species richness and evenness on light-use efficiency, suggesting that at higher diversity, species may be more effective LBH589 in vivo at using resources. These results are consistent with complementarity as a mechanism Sirolimus datasheet linking diversity and function. Recent findings comparing productivity of subtidal turf and foliose algal assemblages describe

foliose assemblages to be more productive due to their greater biomass per unit area and not because of greater production per unit biomass (Miller et al. 2009). The same trend can be described for S. muticum. Due to its longer canopy height, S. muticum is more productive on a per-area basis than on a biomass-specific basis. Finally, in agreement with the similarity hypothesis (Yachi and Loreau 1999), the increase in species richness in native macroalgal assemblages increased the predictability of primary production across space. Contrasting results were, however, obtained for invaded assemblages, where the presence of S. muticum

removed the positive relationship between species richness and ecosystem function predictability. These results suggest that invaded assemblages’ dynamics are less predictable than native dynamics. Further interactions between habitat-modifying species can decrease predictability of community-level effects of an invasion, particularly if invasive species show extremely variable cycles over time (Ward and Ricciardi 2010). The consequences of invasion for the invaded communities, especially with regard to their functioning, have been rarely considered (Pfisterer et al. 2004). selleck products However, the identity of the species being added or removed and its similarity to other species are often of critical importance in determining overall effects (Mooney et al. 1995). In native assemblages, the dominant species were perennial algae such as C. crispus or Corallina spp., while the dominance of the invader varied drastically between seasons. Previous studies have demonstrated a high variability in S. muticum productivity and reproductive development between habitats (Baer and Stengel 2010) and grazing pressure (Plouguerné et al. 2006).