Latushkin A.A., Artamonov Yu.V., Lee R.I., Sysoev A.A., Sysoeva I.V., Fedirko A.V.,
The results of hydrological, hydrooptical and hydrobiological studies performed in the photic zone of the northern part of the Black Sea in October 2016 are presented. The main features of the bio-optical structure formation and its relationship with the hydrological regime were revealed. It is shown that in the zones of the Sevastopol and Feodosiya anticyclones, together with the deepening of the upper mixed layer, the corresponding deepening of the maximum values layer of the total suspended matter concentration is observed. In the southern part of the survey, closer to the center of the Rim Current gyre of the Black Sea, where the depth of the lower boundary of the upper mixed layer is minimal, the rise of the maximum layer of the total suspended matter concentration is noticed. In October 2016 there was noted anomalously high transparency of waters with a small range of spatial variability. It is shown that during this period, there were markedly lower correlations between the vertical distributions of the total suspended matter concentration and the temperature, salinity and density in comparison with the summer period of 2016.
In the water samples, microalgae of nine classes typical for this season were identified. It was found that the values of the metabolic active biomass of microplankton in the sea open part corresponded to the values typical for oligo-mesotrophic waters, while at the Crimean coast it was close to eutrophic ones. The stage of microplankton production/destruction succession is developing, with a forecast for biomass growth in the future.