Distribution of TN and TP in Dongchang Lake from Sediment and Non-sediment Water Recharge Based on MIKE21

摘要

With the continuous increase of urban population, the eutrophication of urban lakes is becoming more and more serious. It is necessary to improve the ecological environment of lakes by water supplement. In this study, TN (total nitrogen) and TP (total phosphorus) of Dongchang Lake before and after water replenishment were sampled and measured, and the hydrodynamic, water quality and sediment MIKE21 models of Dongchang Lake were established. Finally, the variation trend of TN and TP of Dongchang Lake before and after water replenishment of sediment and non-sediment water were simulated, and the following conclusions are drawn: During water replenishment, the TP concentration of each point will rise, and the TP concentration of non-sediment water is higher. After the completion of the water replenishment process, the TP concentration at each point decreases in turn. Under the two water replenishment modes, the difference of TP concentration gradually become narrower, but the TP concentration in non-sediment water is higher. The change trend of TN is similar to that of TP, but after the increase of TN concentration caused by water supply, the concentration of TN remains high in the next few days. This study provides an empirical basis for the development of lake water environment improvement strategies.