Characteristic of microalgae development in the Sea of Okhotsk in winter and modeling of their annual dynamics in Aniva Bay

The possibility of forming of higher diatomic biomasses in winter in the waters of the Sea of Okhotsk water and Aniva Bay is considered. Data of field observations, satellite information, and a mathematical model describing the transformations of compounds of biogenic elements (C, Si, N, and P) are used for this purpose. Field observations confirmed that active microalgae reproduction takes place in the ice of the Sea of Okhotsk. Determinations of their species composition were carried out. The active development of diatoms in winter was confirmed by the analysis of satellite observations during the examination of chlorophyll “a” dynamics on the sea surface. Mathematical modeling yielded quantitative data to characterize the development of diatoms in winter and within the year and interrelated variations in nutrient concentrations and the biomass of planktonic community in Aniva Bay. This is the first analysis of this type for the Sea of Okhotsk.