BENTHIC COMMUNITIES OF THE INFRALITTORAL IN THE N-SPORADES (AEGEAN SEA) - A VARIETY OF BIOTOPES ENCOUNTERED AND ANALYZED

The infralittoral benthos was studied on three islands of the Northern Sporades in the Aegean Sea. Thirteen stations were sampled on both ha rd and soft substrata and 408 taxa were identified, some of zoogeograp hical interest. Multivariate statistical methods such as classificatio n, ordination and Similarities Terms Analysis were combined with exist ing ecological information to delineate the various communities presen t and to point to the indicator species characterising them. The commu nities were then defined using the indicator species and their affinit ies to typical biocoenoses. The main factor responsible for the observ ed distribution proved to be the type of substratum (algal cover or se diment type), which reflects the light and hydrodynamic conditions. Th e observed bathymetric zonation was similar to that of the Balearic Is lands in the western Mediterranean.