Assessing the performance of SWAP model in estimating the production of wheat under salinity and water stress (case study: Birjand, Iran)

Nahvinia, Mohammad Javad; Shahidi, Ali; Parsinejad, Masoud; Karimi, Bakhtiar

Assessing the performance of SWAP model in estimating the production of wheat under salinity and water stress (case study: Birjand, Iran)

Document Type : Original Article

Authors

Mohammad Javad Nahvinia

Ali Shahidi

Masoud Parsinejad

Bakhtiar Karimi

Abstract

In this study, the agro-hydrological model SWAP 3.03 was used for prediction of wheat (Rowshan variety) production under different qualities of irrigation water (1.4, 4.5 and 9.6 dS/m) obtained from three local wells which were used in a factorial plot design with four levels of water depth (50, 75, 100 and 125% of ETc) during 2005-2006 growing season in the Research Field of Birjand University. The model was initially calibrated for crop coefficients of winter wheat based on a study in South Khorasan province. Predicted results directly followed the trend of actual crop production for various amounts and qualities of irrigation water. Predicted and actual crop production was statistically significant at 1% level with an R2 of 0.83. Average yield of Rowshan variety was 10% lower, as compared with the actual yield. However, such differences were not found to be significantly different based on average t-test.

Keywords

Wheat

Irrigation depth and SWAP model

Salinity

Yield