A MEDITERRANEAN FINE-SAND POLYCHAETE COMMUNITY AND THE EFFECT OF THE TUBE-DWELLING OWENIA-FUSIFORMIS DELLE-CHIAJE ON COMMUNITY STRUCTURE

Samples were taken in fine-sand community of the North Latium coast in February and September for two years. Eigthy-eight species of Polycha etes were identified. The most abundant was Owenia fusiformis which wa s highly correlated to the clay fraction in the sediments. Species ric hness and abundance of other polychaete species were related to the ab undance of this tubicolous species which provides a spatial refuge fro m predators and implements sediment stability. There was a persistency in the community structure in spite of seasonal fluctuations in the a bundance of dominant species.