| Along the coast of France in the English Channel, muddy fine-sand communities are restricted to bays and estuaries, but in the southern North Sea they stretch out to larger areas (mesoscale continuum). We studied three regions containing these communities, each subject to different hydrological conditions and contrasting trophic structures of the water column. The Bay of Morlaix was strongly affected by the "Amoco Cadiz" oil spill of 1978 and recovered slowly. The Bay of Seine is influenced by high levels of nutrient input from the River Seine. A retention structure exists in the eastern part ensuring recruitment stability. The Gravelines area in the southern North Sea was invaded by the American jackknife clam (Ensis directus), which became a key species... |
