Numerical simulation study on water environment of Puzhehei Lake

The numerical simulation of Puzhehei Lake water environment is of great significance for preventing Puzhehei Lake water pollution and protecting the water ecological environment in Puzhehei Lake basin. Based on the lack of hydrological and water quality data in Puzhehei Lake Basin, a large number of basic data were collected through pollution source investigation and water quality monitoring. On this basis, a two-dimensional hydrodynamic-water quality model of Puzhehei Lake was established by using MIKE21 model, which simulated the migration and diffusion of pollutants entering the lake, analyzed the current situation of pollution load entering the lake, and analyzed the water flow, hydrodynamic characteristics and migration and diffusion laws of pollutants entering the lake. The results show that: ① The annual load of COD, TN, TP and NH3-N in Puzhehei Lake in 2018 is 4090.0t, 401.3t, 34.4t and 122.6 t; ② Puzhehei Lake has obvious single flow direction and more circulation as a whole, but there is obvious backwater phenomenon in the lower reaches of Puzhehei Lake when the secondary dominant wind is downward.