Evaluation of SWAT in basin-scale hydrological modeling and comparison of the accuracy of the model in using daily and monthly data, case study of Maroon basin

Subject Areas : Article frome a thesis

mostafa mirmehdi ¹ , mojtaba shourian ² , ahmad sharafati ³

1 - Islamic Azad University Science and Research Branch
2 - Shahid Beheshti University
3 - Islamic Azad University Science and Research Branch

Received: 2023-10-19 Accepted : 2024-02-14 Published : 2024-02-26

Keywords: ", Calibration", Maroon", SWAT", , ", SUFI-2 algorithm", . ", Validation", ,

Abstract :

In recent years, basins hydrological modeling has been one of the important issues, the results of which have a significant impact on water resource planning and the extraction of fresh water resources in basins. One of the practical tools in basins hydrological modeling is SWAT (Soil and Water Assessment Tools), this tool can be used as an extension in GIS software. The purpose of this research is to Evaluation the accuracy of SWAT in basin hydrological modeling. The case study is Maroon basin. To calibration of model, used from the flow data measured at the Idenak and Tange-Takab stations in the period of 1991 to 2000 and for the validation of the Idenak station in the period of 2001 to 2017 and in Tange-Takab station in the period of 2001 to 2006. R2 values ranged from 0.61 to 0.85 for daily and monthly flow calibration and from 0.65 to 0.73 for validation. NS coefficient ranged from 0.51 to 0.59 for monthly calibration and from 0.49 to 0.5 for daily calibration. The reason for the reduction of the daily accuracy coefficient compared to the monthly one is that the daily calibrated data in each station is 3450 numbers and for the monthly mode it is 108 numbers. The simulation results show that the SWAT has an acceptable ability in the basins hydrological simulation with a mountainous nature and the process of flow changes in the calibration and validation stage is simulated with acceptable accuracy.