Macrobenthic resources of the shallow soft-bottom sediments in the eastern English Channel and southern North Sea

To obtain a baseline for future comparisons and to assist in the conservation of marine biodiversity, the distribution patterns and faunal composition of shallow (0-15 m depth) macrobenthic assemblages were studied along the French coast of the eastern English Channel and southern North Sea from two surveys conducted in 1998 and 2000. A total of 227 sites were sampled from Cap d'Ailly to the Belgian border, from which a total of 167 species were collected. Species richness, abundance and biomass were all increased in the vicinity of outflows from harbours, major bays and estuaries. Three principal macrobenthic assemblages were defined: (i) an Ophelia borealis medium to fine sand assemblage; (ii) a muddy heterogeneous sediment assemblage; and (iii) an Abra alba muddy fine sand assemblage. The Abra alba assemblage covered approximately 80% of the seabed in the survey area. Sediment characteristics and a latitudinal gradient accounted for a significant proportion of the observed variability in assemblage distribution patterns. In the eastern English Channel, the distribution patterns of species diversity, abundance and biomass values were most continuous, whereas in the southern North Sea a more heterogenous distribution was observed. 2003 International Council for the Exploration of the Sea. Published by Elsevier Science Ltd.