چكيده به لاتين
Mond River Basin is located in South of Iran between Fars and Bushehr provinces with arid and semi-arid climate. Unfortunately, the water and soil resources in the study area have been affected by salt domes. The geographic zones between Dehroud, Dehram, Dejgah tributary to Ghantareh hydrometric stations, with 7000 km2 area, have been considered in soil and water assessment modelling. The sodium chloride (NaCl) is the main factor of the salinity in the Mond River. The hydrological simulation model of the study area in the SWAT tool has been calibrated and validated in SWAT_CUP software based on SUFI-2 algorithm and uncertainty analysis. The calibration process on monthly discharges in hydrometric stations is accomplished based on 2008 to 2011 time horizons. The statistical indicators, P_factor and R_factor criteria and NS and R2 objective functions, in calibration processes in Dehram, Dejgah, and Ghantareh hydrometric stations are 0.75,0.68,0.61,0.64; 0.48,0.25,0.59,0.59; and 0.54, 0.21, 0.78, 0.79, respectively. The validation of SWAT model has been done based on 2012 to 2013 time-horizon. In validation process, the Dejgah hydrometric station has been ignored due to seasonal and drought characteristic. The statistical indicators in validation process of SWAT model are in good and acceptable ranges. A salinity module is added in SWAT source code in the Intel Visual Fortran environment to depict salinity indicators and TDS based on finite difference method. FTCS and Saulyev techniques have been applied to solve 1D advection-diffusion equation based on various boundary condition on the 2008_2013 time horizons. The calibration process based on the 2008 to 2011 and the Validation has been done based on the 2012 to 2013. The salinity indicators consist of K, Na, Mg, Ca, SO4, Cl and TDS parameters have been included in the developed salinity module of SWAT tool. The results indicate in Dehram hydrometric station, R2 and NRMSE criteria on Na, Cl and TDS parameter validation based on boundary condition 2 are 0.64, 0.66, 0.50 and 0.21,0.2,0.28 according to FTCS and 0.69, 0.71, 0.64, and 0.21,0.22,0.29 according to Saulyev techniques. The statistical criteria in Ghantareh hydrometric station on Na, Cl and TDS parameter validation are 0.84,0.91,0.92, and 0.41,0.39,0.27 according to FTCS and 0.81,0.89,0.89, and 0.45,0.4,0.37 according to Saulyev techniques. The results show low accuracy in simulation of Ca and SO4 parameters in the developed salinity module of SWAT. Based on the result, application of Saulyev technique could result in better depictions of salinity indicators in comparison with FTCS technique.
