Simulation of Irrigation and Reservoir Storage in the Develi Basin (Turkey) using Soil and Water Assessment Tool (SWAT)

The efficacy of the soil and water assessment tool (swat) model was evaluated for simulating irrigation and reservoir storage in the develi basin in turkey. develi basin is a semi-arid closed basin that hosts an important wetland, called the sultan marshes. surface water flows in the basin are strongly controlled through ağcaaşar and kovalı reservoirs, which supply water for irrigating the agricultural lands around the sultan marshes. swat is a semi-distributed hydrologic model that can be used for simulating irrigation practices and crop development. in this study, the swat model was established based on topographic, land use, soil, and meteorological data. irrigation in the basin is represented with the auto irrigation tool, which determines the timing and amount of irrigation based on plant water stress factor. sufi-2 algorithm available in the swat-cup program was used for calibration/validation of the model for monthly reservoir storage over the period 2000–2015. this procedure resulted in kling-gupta efficiency (kge) of 0.69 and 0.70, nash-sutcliffe efficiency (nse) of 0.36 and 0.60, and coefficient of determination (r^2) of 0.54 and 0.75 for calibration between the simulated and measured water storage. for validation kge was 0.63 and 0.57, nse was 0.23 and 0.13, and r^2 was 0.50 for validation. results indicated that swat can provide reasonable predictions for simulating monthly irrigation and reservoir storage in the develi basin.