Modelación numérica de la hidrodinámica, del oxígeno disuelto y la demanda bioquímica de oxígeno en sistemas con vegetación

this work deals with the implementation of a numerical model to simulate hydrodynamics and transport of pollutants in flows where submerged vegetation is present. the model is based on the shallow-water equations to calculate the mean velocities, emphasizing calculations of the shear stress produced by both the vegetation and turbulence. the advection-diffusion-reaction equation is used to calculate the transport of the biochemical oxygen demand and the dissolved oxygen. the main objective is to simulate the transport of these substances and the pollution filtering and reaereation functions of plants in water bodies such as wetlands. in the obtained velocity fields, the change of the behavior due to the restriction imposed by the vegetation can be seen. the bod and do concentrations are influenced by the residence time and the reaereation from the atmospheric exchange and plants breathing. as a conclusion, the model represents very precisely the behavior of dissolved substances transport in flows with presence of vegetation and can be applied to different ecosystems, being capable to predict the path and fate of pollution.