Research on the impact on runoff by time-scale of the precipitation in karst basin in view of MIKE SHE model: A casein Liudong river of the Hongshuihe system

Runoff is the outcome of hydrological response to precipitation by river basin system. The essence is that the precipitation is reallocated spatially and temporally within the basin. As one of the greatest uncertainties, spatial and temporal characteristics of precipitation are the main factor that affects the runoff modeling and the other hydrological problems. To research the impact on runoff by precipitation time-scale in karst basin, MIKE SHE is applied to five floods in a typical karst basin, and the correlative parameter of the MIKE SHE is selected and calibrated in combine with the unique landforms and hydrological characteristics in the karst basin in this paper. Moreover, in order to study the impact on flood modeling process by variation in precipitation time, the time-scale of precipitation data is changed in this research. The result shows that runoff will increase and flood peak will delay with the increase in temporal scale.