Yermak Plateau revisited: spatial and temporal patterns of meiofaunal assemblages under permanent ice-coverage

摘要

Benthic sampling between 1997 and 2006 on the Yermak Plateau, a permanently ice-covered submarine peninsula northwest of Svalbard, exhibited regional differences with generally higher meiofauna numbers in southern and western parts (～2,250-2,300 ind. 10 cm~(-2) in the southwest, compared with ～1,200-1,350 ind. 10 cm~(-2) in the north-east). Distribution patterns suggest a current-driven lateral input of POM, produced in the high-productive Marginal Ice Zone, with increased intensity along the western slope of the plateau. Significant correlations between comparably 'fresh' sediment-bound phytodetritus and the taxonomic composition of meiofauna assemblages indicate that food quality decisively affects the community structure. The long-term development of meiobenthic communities showed no clear trend; however, a comparison of summer and winter data exhibited higher meiofauna densities and a more diverse composition in July samples, The predominance of small nematodes in the summer samples might point to reproductive activities stimulated by increased food availability. The taxonomic composition of nematode assemblages showed distinct regional differences, thereby indicating more stable environmental conditions in northeastern parts of the Yermak Plateau.