Hydrological Modeling of Zolachai Watershed in Salmas Townshipe (Chehric Alia) in GIS Environment by Using of ARC SWAT Model

  In the present study, the ARC SWAT model in ARC GIS software was used to model the Zolachai watershed in the city of Salmas (Chehric Alia). For sensitivity analysis, calibration, SPSS statistical software was used. In the model used from precipitation data, minimum temperature, maximum temperature and daily relative humidity of rain gauge and synoptic stations in the study area for 35 years (1984 to 2019), for five statistical periods of 7 years, for April, October and November used. To calibrate the ARC SWAT model in SPSS statistical software, indices of uncertainty, coefficient of determination, standard deviation, significance level and Fisher-in-law coefficient were used. The results of the uncertainty index for April, October and November were 0.8, 0.30 and 0.5 percent, respectively, and the watershed determination coefficient index for these three months was 0.0114, 0.5788 and 0.1551, respectively. Showed the percentage the standard deviation index was 0.97 percent for April, 07.07 percent for October and 1.09 percent for November. Significance level index for these three months showed 0.87 percent Fisher Sandkor coefficient as one of the important indicators of watershed validation for each quarter showed a number of 0.91 percent.