Publication Abstract

The centre of the English Channel is characterised by a bedload parting zone resulting from asynchrony between the M2 and M4 tides. Combined with strong currents in the area, the net result is a marked divergence of net sediment transport to the west and east of the parting zone. Over millennia this has resulted in a large scale sorting of surficial sediments, such that they are coarse (or even absent) around the axis of the parting zone but become progressively finer with distance from that zone. At the Dover Straits there is also a bedload convergence zone where fine sediments accumulate. This extreme environmental forcing is reflected in the unusual distribution of benthic habitat and fauna. Benthic faunal assemblages show a symmetrical distribution, with those furthest from the bedload parting zone on either side being more similar to each other than that inhabiting the parting zone itself.  With increasing demands to assess the state of health of the seas, it is important that such localised variability is recognised as a natural phenomenon against which the relative magnitude of human impacts can be assessed.