Ecological Systems and Devices Annotation << Back Modeling of the Highly Eutrophic Ecosystem in the Coastal Waters of the Black Sea N.V. Solovjova The article uses a proposed mathematical model of the highly eutrophic ecosystem in the coastal waters of the Black Sea to calculate annual changes in biomass and concentrations of seven main components: phytoplankton, macrophytes, zooplankton, biogenic elements, suspended organic matter, dissolved organic matter, and fi sh. The results were compared with observational data from fi eld expeditions and remote observations. A comparative analysis given noncontradictory results, allowing the model to be used for both diagnosing the current state of the ecosystem and predicting its future under anthropogenic pressure in conditions of climatic instability. Keywords: ecosystem, Black Sea, eutrophication, modeling. DOI: 10.25791/esip.11.2024.1484 Pp. 20-26.