Influence of Different Watershed Subdivision Numbers on Simulation Results of SWAT Model

It is simulated the runoff and sediment load in the condition of the different sub-watershed by the SWAT model and analyzed the relationship between the numbers of sub-watershed and the response of the simulation results by studying Shitoukoumen Reservior catchment basin area.It is revealed that when the sub-watershed is divided into too small or too large,the actual threshold is unable to get the satisfactory simulation results.The sensitivity of runoff is low but the sediment load is relatively high within the threshold fluctuation range.Finally,it is confirmed that the reasonable numbers of watershed sub-basins in this area is determined,which can provide a theoretical reference for the non-point source pollution simulation of this area in the future.