Construction method of water system communication mathematical model

The invention discloses a construction method of a water system communication mathematical model, which comprises the following steps of: firstly, constructing a one-dimensional river network water-sediment mathematical model basic equation which specifically comprises a water flow continuity equation, a water flow motion equation, a sediment continuity equation, a riverbed deformation equation, a river network branch point continuity equation and a river network branch point motion equation; a two-dimensional mathematical model is constructed to simulate water level and water flow changes of two-dimensional free surface flow neglecting layering, and a continuous equation and a momentum conservation equation of dynamic flow are solved through an ADI second-order precision finite difference method; according to the technical scheme, the water level of the Dongting Lake area under different flow levels can be verified, and the average value of water level relative errors is calculated; the model does not consid