477 / 2024-04-15 16:21:11

Decline in the Danjiangkou Reservoir total nitrogen concentration in response to the input decrease in tributaries

Danjiangkou Reservoir; total nitrogen concentration; hydrodynamic and water quality model; downward trend

Subtheme 3: Eco-hydraulics and Environment > Topic 2: Water Eco-environment Monitoring and Simulation

In this study, we analyzed the trends of the total nitrogen concentration in the Danjiangkou Reservoir and the main tributaries, Han River and Dan River, from 2012 to 2016. Then, a sensibility analysis for the total nitrogen concentration in the reservoir due to Han River and Dan River was conducted based on a two-dimensional hydrodynamic and water quality model. The results indicated that the total nitrogen concentration in Danjiangkou Reservoir exhibited a significant downward trend annually and decreased ~25% from 2012 to 2016. The input total nitrogen loading from Han River and Dan River showed a similar downward trend annually. The sensibility analysis showned that Han River is the most influential inflow affecting the total nitrogen concentration in the Danjiangkou Reservoir and plays a decisive role in the water quality of the South-to-North Water Diversion Middle Project.