Renmin Zhujiang (Jan 2022)
Distribution of Pollutants in Nandu River Estuary in Different Environments
Abstract
In view of the frequent tropical storm surge in Nandu River Estuary in recent years,the increasing population in Haikou City each year,severe pollution emissions,and increasing upstream water use year by year,this paper studies the pollutant distribution in Nandu River Estuary under the storm surge and reduction of upstream water inflow on the basis of the hydrodynamic-water quality model.In addition,the changes of pollutants under different environments are analyzed.The results demonstrate that pollutants are mainly distributed on the left bank of the river and are mainly in striped shape due to the topography of the river.When the upstream flow is reduced by 20%,the effect of the tidal current is more significant,and pollutants are greatly affected by convection;the pollution zone becomes narrower,and the diffusion distance is the farthest.When the downstream tidal level is raised by 0.4 m,the interaction between the upstream inflow and tidal current is obvious;the flow rate decreases,and the pollutant retention is serious.In this case,pollutants mainly diffuse to the upstream by diffusion.Therefore,the upstream water resources should be effectively regulated and used,and the water surrounding the sewage outlet should be monitored with more efforts to provide a reference for the water environment management of the estuary section of Haikou City in the future.
