simulation of rainfed wheat yield using aquacrop model, case study: sisab rainfed researches station, northern khorasan

modeling of crop growth plays an important role in evaluation of drought impacts on rainfed yield, choosing an optimum sowing date, and managerial decision-makings. aquacrop model is a new crop model that developed by food and agriculture organization (fao), that is a model for simulation of crop yield based on “yield response to water“ with meteorological, crop, soli and management practices data as inputs. this model has to be calibrated and validated for each crop species and each location. in this paper, the aquacrop has been calibrated and evaluated for rainfed wheat in sisab station (northern khorasan). for this purpose, daily meteorological data and historical yield data from two cropping season (2007-2008 and 2008-2009) in the sisab station have been used to calibrate this model. next, meteorological data and historical yield data of five cropping season (2002-2003 to 2006-2007) are used to validate the model. the result shows that the aqucrop can accurately predict crop yield as r2, rmse, nrmse, me, and d-index are achieved 0.86, 0.062, 5.235, 0.917 and 0.877, respectively.