Concluding remarks:

1. Guri Sogn Andersen & Stein Fredriksen Department of Biology, Program for Marine Biodiversity University of Oslo The kelps are not only of great importance as primary producers along the shores of Norway, they provide a highly heterogenic habitat able to support a diverse and numerous flora and fauna. Some of these organisms are themselves primary producers that may contribute significantly to the amount of carbon flowing through this system. This study will focus on the floral epiphytes associated with Laminaria hyperborea (Gunn.) Foslie and their biomass in relation to wave-exposure and season. The field area was located nearby Finnøy and Seterøy. The areas investigated are located nearby Finnøy in Møre og Romsdal, Norway. In total 9 stations were sampled. Three levels of wave-exposure were identified (NIVA). All samplings were done by SCUBA-diving at approximately 5 m depth. The investigations were conducted in April, June, September and November 2005. Here we will present data from April and September. Exposure is a factor related to currents and particularly waves, which in addition to be a physical stress factor, also may act as a key determinant of macro algal production through water motion. By comparing differences in epiphyte biomass between stations in an exposure gradient, we hoped to get an indication of to what extent wave-exposure affects this production. Møre og Romsdal Fig 1. In April we found the ratio of epiphyte biomass to stipe length to be positively correlated with increased level of exposure. In September however this ratio seemed higher in the moderately exposed areas. Total biomass was significantly larger in September than in April. (E = exposed, M = moderately exposed, S = sheltered. Error bars indicating confidence intervals (α=0,005)) Fig. 2. In April we found Laminaria sp. (juveniles), Palmaria palmata, Membranoptera alata and Ptilotagunneri dominating at the exposed areas. In less exposed areas, with the exception of Ptilota gunneri, this dominance seemed much less pronounced. The presence of Delesseria sanguinea, Polysiphonia elongata and Rhodomelaconfervoides became more evident. (E = exposed, M = moderately exposed, S = sheltered. Error bars indicating confidence intervals (α=0,005)) Fig 3. In September, much of the same species were dominating, but a trend in species composition related to exposure was not as clear. Polysiphonia was no longer present at any of the stations.It is probably worth noting that Palmaria palmata was absent in sheltered areas both in April and September. (E = exposed, M = moderately exposed, S = sheltered. Error bars indicating confidence intervals (α=0,005)) Kelp associated epiphytes and their level of biomass production in relation to wave-exposure and season. Concluding remarks: Level of exposure has an effect on biomass, and possibly on species composition of floral epiphytes associated with Laminaria hyperborea. Epiphytic and understory algae are an important food source for a number of different faunal groups. Figuring out the connection between level of exposure and level of primary production, could be useful in estimating the possible level of secondary production in an area. This would be valuable information for resource management.