Comparison between AquaCrop and radiation-thermal production potential models for potential yield estimation in part of Moghan plain, Ardabil Province, Iran

Potential yields for six cultivated crops, wheat, barley, sugar beet, cotton, maize and soybean has been calculated using the AquaCrop and radiation thermal production potential method or FAO model in Khodaafarin region, Ardabil province, Iran. Determination coefficient, normalized root mean squared and index of agreement for potential yield in AquaCrop was 0/99, 21/72 and 0/99 and for FAO model was 0/97, 54/25 and 0/96 respectively. Also for comparison between the potential biomass for AquaCrop and FAO model the Determination coefficient 0/98, 0/93, normalized root mean squared 23/55, 58/10 and index of agreement 0/98, 0/93 was calculated, respectively. Based on the results, the AquaCrop model has better performance in comparison with to FAO model. The AquaCrop using less data calculation and more outputs and applications comparing with FAO model but has a more accuracy. The crops has been ranked based on the calculated yield gap fractions. The lowest yield gap fraction belongs to barley, soybean, sugar beet, wheat, cotton and maize respectively. This ranking could be used as an ecological coefficient for the region cropping pattern.