Genus-specific response of kelp photosynthetic pigments to decomposition

Abstract Detritus is widely considered to be dead organic matter. However, recent studies have shown that kelp detritus can functionally equivalent the attached plant. This significant, because makes up ~ 42% of all plant biomass. In Northeast Atlantic, on detrital photobiology been restricted genus Laminaria . Here, we present data from a 46 d in situ experiment investigating effect decomposition photosynthetic pigment concentrations and stoichiometry four Atlantic species three genera. We corroborate lack pigments cold temperate as identified by previous but show photophysiology other genera responds differently. While Saccharina latissima displays an idiosyncratic parabolic response, annual thermally plastic Saccorhiza polyschides seems become less pigmented with increasing age. If S. becomes increasingly dominant future parts warmer this may translate lower potential at forest scale. given our somewhat ambiguous species, conjecture requires further investigation into photosynthesis.