BENTHIC COMMUNITY PATTERNS REFLECT WATER COLUMN PROCESSES IN THE NORTHEAST WATER POLYNYA (GREENLAND)

Benthic community patterns were investigated in the Northeast Water po lynya (Greenland) during the summers of 1992 and 1993 to elucidate to what extent the bottom fauna is influenced by the dynamics of the over lying water. Five different fractions of the benthos (foraminiferans, nematodes, polychaetes, peracarid crustaceans, and epibenthic megafaun a), ranging in average adult body size over 6 orders of magnitude (fro m about 100 mu m to about 10 cm), were sampled quantitatively at 69 st ations in water depths from 40 to 515 m. Total abundances of nematodes , polychaetes and peracarid crustaceans were found to be primarily cor related with parameters characterizing the potential benthic food supp ly (water column pigment and nitrate concentrations, sediment bound pi gments and sediment biological activity), whereas abundances of forami niferans and megabenthos were largely associated with seabed propertie s. Four benthic zones were distinguished by separately analysing the f aunistic composition and distribution of the five community fractions for Ob Bank, Western Westwind Trough, Eastern Westwind Trough, and Bel gica Trough, This pattern was shown principally to reflect pelagic reg imes differing in surface water hydrography, ice cover and euphotic pr oductivity, This is the first time that a synoptic study of several be nthic community portions spanning such a range in sizes and life style s has been performed in a polar shelf ecosystem. Our results indicate that abundances as well as composition of Arctic benthos are largely i nfluenced by mesoscale pelagic processes, and thus provide further evi dence for the importance of the benthic-pelagic coupling in high latit ude seas.