Deep-Sea Benthic Community Exposed to Strong Near-Bottom Currents on the Scotian Rise (Western Atlantic)

摘要

This paper gives an overview of the structure of a benthic community at 4626 m depth on the Nova Scotian continental rise. Here, adundances of polychaetes, bivalves, isopods and tanaids are conspicuously high compared to those reported from comparable depths. Bacterial numbers and ATP concentrations are also high. We suspect that these anomalous result from enhanced food availability caused by the strong near-bottom currents that flow through the area. The polychaete and bivalve faunas have few adults and high species dominance suggesting that currents create large-scale, sediment-transporting disturbances. The composition of the crustacean fauna supports this inference in that it is dominated by forms that can enter the seabed and thereby escape adverse conditions on the sediment surface. (Author)