(Table 1) Results of measurements of production characteristics of phytoplankton and some physical parameters of the environment in the northeastern Norwegian Sea in July 1995

From July 4 to 18,1995 surface chlorophyll a concentrations (C_cs) and integral primary production (C_ps) were studied in the northeastern part of the Norwegian Sea (73°42'N; 13°16'E), over a test area where an accident of the nuclear submarine Komsomolets had taken place. It was found that during this interval C_cs decreased by factor of about 3.3 (from 0.78 to 0.24 mg/m3); average chlorophyll concentration within the photo-synthetic layer (C_cl) decreased by factor of about 3.5 (from 0.97 to 0.28 mg/m3). The value of C_ps in the water column varied slightly (from 445 to 539 mg C/m2 per day), since decrease in C_cl was compensated both by 1.5-fold growth of the photosynthetic layer thickness (from 40 to 60 m) and by 2.1-fold increase in its average assimilation number (from 0.58 to 1.20 mg C/mg chl a per hour). Monthly averages of C_ps were obtained from published data on seasonal C_cs changes and on the level of incident solar irradiation. They were found to be less than 100 mg C/m2 per day in March and October and 100-500 mg C/m2 per day in April-June. Annual primary production calculated from above values was equal to 105 g C/m2.