Efficiency of SWAT model for determining hydrological responses of marl formation

Abstract

The change in the amount of erosion, sedimentation and permeability is directly related to the change in the physical and chemical properties of soil, especially for marl formation (MF). Any hydrological modeling should be verified with land use (LU) and surface parameters of MF. For this purpose, soil hydrological response (HR) and soil loss were estimated for different LU units in Iran’s Sorkhab MF using ArcSWAT model. The output of the model was compared with the real data obtained from Kamphorst rainfall simulator (RS). The results showed that modeling well separated the changes through HR in different LUs of MF. Moreover, there was no statistically significant difference (R2 = 0.72 and ENS = 0.68) between results of RS and SWAT modeling (p < 0.05). The estimated sediment and the runoff rate were 4.62 t ha−1 and 6.54 m3 ha−1, respectively, for the large simulated unchanged units, and the amounts of sediment and runoff were 87.8 t ha−1 and 8.28 m3 ha−1, respectively, for units under land-use change (LUC). Generally, SWAT model has the ability to show the soil HR under LUCs in MFs.