Comparison of FAO Aquacrop and SWAP Agro-Hydrological Models to Simulate Water and Salt Transport during Growing Season of Winter Wheat

Abstract

In this study, the performance of SWAP and FAO Aquacrop agro-hydrological models to predict water flow and salt transport in soil profile was evaluated under water and salt stresses during growing season of winter wheat. Field experiments were conducted with three levels of saline irrigation water including: S1, S2 and S3 corresponding to 1.4, 4.5 and 9.6 dSm -1 and four levels of irrigation depth including: I1, I2, I3 and I4 corresponding to 50, 75, 100 and 125 percent of crop water requirement with three replications for 2005-2006 period in Birjand region in Iran. The SWAP and Aquacrop models predicted the soil water content with an appropriate precision. The average normalized root mean square error (NRMSE) of calibration in soil water content prediction by SWAP and Aquacrop models, were calculated 4.81 and 18.91 %, respectively, and for validation, were calculated 7.34 and 19.6 %, respectively. The average normalized root mean square error (NRMSE) of calibration in ECe prediction by SWAP and Aquacrop models, were calculated 8.87 and 37.34 %, respectively, and for validation, were calculated 13.6 and 36.93 %, respectively. Results indicated that the Aquacrop model predicted ECe with more error compared with SWAP model. * Corresponding Author: Vahid Rezaverdinejad  verdinejad@gmail.com