SPATIAL AND TEMPORAL DISTRIBUTION PATTERNS OF BENTHIC FORAMINIFERA INTHE NORTHEAST WATER POLYNYA, GREENLAND

Abundance, biofacies and ATP content of benthic foraminifera(> 63 mu m ) were studied in the Northeast Water (NEW) Polynya (77-81 degrees N, 5-17 degrees W) over the ice-free summer, 1993, to investigate how a p olynya system might influence the underlying benthic community. In the living assemblage, distinguished by Rose Bengal staining, over 60 tax a could be identified. The biofacies identified was similar to that of other Arctic shelf habitats. Foraminifera were counted in 3 size frac tions (63-125 mu m, 125-250 mu m and > 250 mu m), with 65% of the fora minifera occurring in the smallest size fraction (63-125 mu m). Total abundances(> 63 mu m) in the uppermost 1 cm averaged approximately 200 ind/10 cm(3) and declined down-core, as did the number of species. Ab undances and species composition correlated positively with sediment c hlorophyll and ATP content, with maxima occurring in the shallower nor thern regions of the polynya, suggesting a general dependence on food. Foraminifera biomass was estimated to be 0.1-0.3 g C-org/m(2). Abunda nces: biomass and ATP content were comparable to ice-free, deep-sea re gions in the Norwegian Sea. Temporal changes observed over a 2 month p eriod at one location were difficult to distinguish from spatial and a nalytical variability. Contrary to expectations, growth was unpronounc ed at the community and at a species level, implying either a delayed response of the benthic foraminiferal community to food inputs from th e overlying water column or the presence of biological limitations oth er than food, such as predation.