Study on dynamic water environmental capacity of the river network in Wenhuang plain based on the hydrodynamic and water quality coupling model

The calculation of water environment capacity (WEC) is the basis of pollution control, and it is of great significance to the formulation of water environment quality management scheme meanwhile. Due to the precipitation varies with seasons, WEC has an obvious temporal dynamic feature, that is ignored in the traditional method under a single fixed hydrological condition design hydrological condition. Thus, on the basis of the hydrodynamic and water quality coupling model, the trial-and-error method was adopted to investigate the traditional and dynamic (by month) WEC of NH3-N of Wenhuang plain of Zhejiang Province in this paper. The result shows that WEC had a relatively large fluctuation during the year, of which the value was distinctly lower in dry season and the peak was present in June. It can be concluded that the dynamic algorithm was more in line with the actual circumstances compared with the traditional method.