General watershed water circulation simulation calculation method based on natural sub-watersheds

The invention relates to a general watershed water circulation simulation calculation method based on natural sub-watersheds, the natural sub-watersheds are used as calculation units for runoff production and slope confluence, and the surface rainfall input of each sub-watershed is calculated by adopting the high-fault-tolerance surface rainfall calculation method disclosed by the invention. Different runoff production and confluence models can be adopted for all the sub-basins to fully reflect climate and underlying surface characteristics, river network confluence is achieved between the sub-basins through a topological relation model and a hydrodynamic model, and finally the flow process of the outlet section of each sub-basin is obtained through calculation. For the influence of the cross-basin water diversion project, the influence is generalized into the increase and decrease influence of single river flow evolution on the outlet flow of the nearest downstream sub-basin under the input boundary of the u