Special features of the vertical distribution of the phytoplankton in the Kerch coastal waters (Black Sea) in the summer season of 2019

Following the increasing anthropogenic load on the Black Sea ecosystem, monitoring surveys of phytoplankton as the foundation of the trophic pyramid become more and more essential. The data on composition and functional characteristics of the phytoplankton in the Kerch coastal waters (Black Sea), collected in the course of the expeditionary trip of the Research Vessel “Professor Vodyanitskiy” in July, 2019, are presented. The samples were collected and processed using standard methods of hydrobiological research. Estimation of the biomass was conducted using the enumerative volumetric method based on the personally collected measurement data. Mathematical processing was performed with the original software “Phytoplankton”, developed in the Laboratory of the Systems Analysis of Aquatic Biological Resources and Databases. The changes in phytoplankton composition within the hydrological layers are shown; the quantitative parameters of the development of phytoplankton communities are analyzed. Thespecies composition and the combination of the most abundant species were compliant with those of the summer season. The highest species diversity and quantitative values of the plankton were recorded in the surface and thermocline levels. Coccolithophore Emiliania huxleyi comprised the majority of its abundance, and the dinoflagellates were the most sizable in terms of biomass. The cold mixed layer was inhabited by low-species algocoenoses with low abundance and biomass.