Mathematical Modelling of Pollutant Transport (Phosphates) in the Waters of the Azov Sea near the Village of Dmitriakovka

This study is devoted to modeling phosphate pollution in the Sea of Azov near Dmitriyevka, originating from a deep-water wastewater discharge outlet. High phosphate concentrations in water bodies can cause algal blooms and eutrophication, i.e., rapid growth of aquatic vegetation, which ultimately leads to a decrease in oxygen concentration, vital for fish and other aquatic organisms. A mathematical model for pollutant transport has been developed, based on a system of convection-diffusion equations that accounts for the spatial distribution of temperature and salinity. For the numerical solution of the equation system, an efficient alternating-triangular iterative method was applied, enabling the solution of large-dimensional systems of linear algebraic equations with ill-conditioned matrices. A research and forecasting software suite was created in C++ that implements the developed mathematical model and visualizes the calculations. Model verification was performed based on field monitoring data from 2020 and satellite sensing results. The modeling error was about 14%.

Keywords

pollutant transport; shallow water body; mathematical model; algorithm; research and test complex.

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