Simulation of degradation,diffusion and distribution of total nitrogen pollution influenced by tide and runoff in Yongjiang River
Based on the Finite-Volume Community Ocean Model(FVCOM),the hydrodynamic model of Ningbo-Zhoushan sea area is established in this paper.Combined with the monitoring data of sea water,the distribution of total nitrogen concentration in the area and the dynamic factors affecting the transport of pollutants are analyzed.Then,the apparent degradation coefficient method was used to supplement the decaying mechanism of tracer concentration in the DYE module,and the degradation,diffusion and distribution of total nitrogen pollutants from Yongjiang into the sea were simulated and analyzed under the conditions in the high flow period of 2021.The simulation results show that the total nitrogen pollutants imported from Yongjiang into Ningbo-Zhoushan sea area is an important factor contributing to the high concentration of total nitrogen in the coastal waters of Zhenhai and Beilun districts in Ningbo in summer 2021.Under the combined action of tidal and Yongjiang runoff,the total nitrogen pollutants imported from Yongjiang into Ningbo-Zhoushan sea area will significantly affect the sea water quality in the eastern and northem sea areas of Ningbo.Taking the summer of 2021 as an example,after considering the degradation process,the simulation results show that the total nitrogen pollutants imported from Yongjiang will increase the seawater total nitrogen concentration of Ningbo coastal station by about 0.7mg/L within 90 days.
万方数据
维普
