Uniform bathymetric zonation of marine benthos on a Pan-Arctic scale

• We studied bathymetric zonation of benthos in the Central Arctic over a depth range spanning 14–5416 m. Our analyses indicated faunal boundaries at depths 650–950 m and 2600–3000 m, delineating sublittoral bathyal fauna abyssal faunas, respectively. original previously published data collectively suggest uniform patterns overturn benthic assemblages throughout entire continental slope plain. While numerous regional studies globally have been done, few large-scale exist, no ocean-scale focused on Ocean to date. In present work we, hence, examined macro- megabenthos from shelf plain (14 – 5416 m) regionally extending Fram Strait Beaufort Sea (as whole hereafter called Arctic). Based 104 quantitative (box-corers grabs) 37 semi- (trawls) samples compiled different we evaluated abundance, biomass diversity, also compared species composition among samples. Abundance decreased with > 3000 ind. −2 40 g ww ∼ 130 < 1 corroborating previous studies. Diversity showed parabolic pattern, peaking 100–600 Cluster analysis revealed four (macrofauna) five (megafauna) groups assemblages, including three that covered upper lower plains relatively little overlap (named Lower Shelf Upper Slope , Abyss ). Substantial changes community were observed (between ) ), so interpreted these two horizons as major boundaries. The first boundary (650–950 corresponds transition consistent second (2600–3000 reflects decrease diversity within Bathymetric For some regions Ocean, foremost for area north Greenland Canadian Archipelago, are still unavailable further research is needed.