MODELING OF THE FLOW CHANGES DUE TO RESERVOIR OPERATIONS AND THE IMPACTS ON AQUATIC ECOSYSTEM DOWNSTREAM

The modification of flows due to river regulations has great impacts on the downstream aquatic ecosystem. It is important to quantitatively evaluate these effects, and eco-hydraulics models that integrate hydrodynamics processes and ecological processes are proved efficient methods to achieve the objective. This paper developed both a one-dimensional hydrodynamic and water quality model for the entire river and a two-dimensional model for local sections. Through the model simulations, the changes of the river flows due to reservoir operations can be quantified. The developed model was applied to the Lijiang River, which is a typical mountainous river and is famous for the delicacy scenery. The river ecosystem is largely affected by the flow regulations for tourism cruise through the operations of multiple reservoirs in the upstream. The model results are seen in close agreement with the observations, and these results provide the external forcing to the ecological module.