Simulation of climate change effects on potato crop yield using AquaCrop plant growth model

This study was carried out using AquaCrop plant growth model to simulate potato crop yield in irrigation levels of 100, 80 and 65 percent of plant water requirement under climate change conditions in Shahrekord region. The data of two years of 2013 and 2014 were used to calibrate and validate the AquaCrop plant growth model. In order to investigate the effect of climate change on product yield, the output data of the HadCM3 general circulation model under two scenarios A2 and B1 for the periods 2011- 2030 and 2046-2065 are downscaled using LARS-WG model and used as inputs of the growth model. Based on the results, the simulation of potato yields with the AquaCrop plant growth model was carried out with high precision so that the average difference between observed and simulated values in calibration and validation stage was 0.56 and 0.68 ton/ha, respectively. Also, the mean absolute error (MAE) for simulating minimum temperature, maximum temperature, sunshine hours and precipitation with LARS-WG model was 0.05, 0.03, 0.01 and 0.16, respectively which reflects the good performance of the model in producing climate data for the future periods. Simulation results showed that the potato yield for the periods 2011-2030 and 2046-2065 under the A2 scenarios was 15.8 and 24.5 percent, respectively, and under B1 scenario, 11.8 and 22.4 percent increase compared to the base period. Also, for I80 and I65 treatments, the yield value decreases in both the future periods and the two scenarios campared to the base period.