PECULIARITIES OF THE STRUCTURAL ORGANIZAT ION OF MACROBENTHOS IN THE BIOTOPE WITH PRONOUNCED GRADIENT OF SALINITY

The predetermined by the gradient of salinity structure of macrobentho s is analyzed using the wide range of statistical methods (classificat ion and ordination) at the example of the estuary of Black River and t he White Sea. The studied system was shown to represent continuity com plicated by the presence of specific complexes determined by the local environmental conditions. Two communities separated by the salinity o f 14 to 16% were revealed within this continuity. This delimitation is apparent when the integral characteristics of the community are used. However, this delimitation is masked when used the methods of ordinat ion. In general, the methods of classification (cluster analysis) and ordination (gradient analysis) give principally coincident results, bu t emphasize different tendencies of distribution.