Depth distribution of canopy?forming algae of the order Fucales is related to their photosynthetic features

Photosynthetic features and dark respiration of different species dominant canopy-forming algae the Order Fucales (Phaeophyceae) consistently change with depth. efficiency (?) light at compensation (Ic) according to amount available each depth, ? increasing Ic decreasing However, values saturation (Ik) do not show any depth pattern. Deep-water higher photosynthesis (Pmax) lower (Rd) than shallow water ones. This result contrasts expected reduction Pmax in low environments shown by terrestrial plants but is consistent other studies performed macroalgae, suggesting that same trend variation marine environment. The positive correlation between cannot be explained differences thickness as all tested an extremely high morphological similarity. increase also coupled N P content branches, which points nutrient-limited species.