Abstract
Groundwater and surface water processes depend on hydrological assessments. There are underground waters that enter the catchment area from outside the catchment area, which do not necessarily flow within the catchment area, or they leave the catchment area and enter the adjacent catchment area. In order to achieve the goal of this research, which is to include the effect of this event on hydrological simulation, it is necessary to use the Soil and Water Assessment (SWAT) software, a hydrological model was built and two modeling scenarios were compared. In this project, by developing a comprehensive hydrological model based on the SWAT model, Base flow simulation for four hydrometric stations and surface runoff was started in the Bazfat basin in the period from 2005 to 2013, and reanalysis data and ground observations were also used in this study. In order to calibrate the model, SWAT-CUP software and SUF12 algorithm have been used. Also, in this research, time series, separation of base flow, sensitivity analysis and calibration of the results were investigated. The results show that the hydrological simulation of the basin under the conditions of the first scenario, in which the SWAT model simulated both base flow and direct runoff, compared to the second scenario, which used the Point Source feature to separate the base flow from direct runoff based on the data of hydrometric stations were introduced and used as input data to the SWAT model. In general, there is no significant difference, the reason for this is the effect of the karst basin of the Kohrang River in the vicinity of the Bazoft catchment basin. The obtained results provided a better understanding of the separation function of base flow as Point Source under the second scenario in the karst basin.