Deep-sea meiobenthic communities underneath the marginal ice zone off Eastern Greenland

Abstract

Marginal ice zones (MIZ) are known to be the most highly productive systems in the Arctic Ocean with large amounts of primary production reaching the deep seafloor. This study characterizes the effect of the ice-edge related primary production and subsequent phytodetritus sedimentation on deep-sea meiobenthic communities, particularly nematodes, along the Eastern Greenland continental margin in July 2000. Results were based on data from six stations along a depth transect crossing the MIZ with the shallowest stations under the ice-cover (656 and 1,198 m), intermediate stations at the ice-edge (1,560 and 2,129 m), and deepest stations in ice-free areas (2,735 and 3,033 m). The presence of the ice-cover significantly affected the availability of organic matter on the deep seafloor. The present results confirm a close bentho-pelagic coupling in the area of investigation. Enhanced flux of phytodetritus from primary production to the benthic system appears at stations underneath or close to the ice-edge and at the sampling sites in ice-free areas. The availability of phytodetritus at these stations enhanced bacterial activities, meiofauna abundances, and the number of nematodes species.