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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. Our focus will be on the floral epiphytes associated
with Laminaria hyperborea
(Gunn.) Foslie
and their level of production in relation to wave-exposure and season.
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. Epiphytic and understory
red 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.
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. We
will present data from April and September, as the samples from June and
November are not yet fully investigated. 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. In April we found Laminaria sp. (juveniles), Palmaria palmata, Membranoptera alata and Ptilota
gunneri
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 Rhodomela confervoides became more evident. Much the same
species were dominating in September, but a trend in species composition
related to exposure was not as clear. Total biomass was considerably larger
in September than in April. Level of exposure has an effect on biomass, and
possibly on species composition of floral epiphytes associated with Laminaria hyperborea.
The poster (Received the price for best poster-presentation by young scientist at
the NMSC 2006)
 
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