the effect of climate change on sorghum's yield (case study: zanjan province, abhar plain

Objective: the most important climate variable, closely related to other variables, is temperature, whose changes trigger a series of chain reactions in the environment. also temperature is a key factor influencing plant growth. therefore, in this study, future temperature trends in the abhar region, affected by climate change, are analyzed over upcoming periods and compared with the historical observation period. crop yield in future and various planting periods is predicted using the aquacrop crop simulation model and climate change models. material and methods: the observation period spans from 1986 to 2010 ad, with near, middle, and far horizons projected for 2011-2045, 2046-2079, and 2080-2100, respectively. lars-wg software is employed alongside the noresm1-m model under rcp8.5 and rcp4.5 emission scenarios to downscale the results of the general circulation model. additionally, a scenario file is created in this study. results and discussion: results show that the highest yield of 4.64 tons per hectare occurs on september 27, while the lowest yield of 0.65 tons per hectare is on september 16. moving the traditional planting date from october 7 to september 27 results in a yield increase of 0.15 tons per hectare. in the distant future horizon, the maximum yield 6.39 tons per hectare will be achieved on october 27. furthermore, sorghum yields are projected to increase in future timelines, likely due to its involvement in the c3 photosynthetic system. conclusions: consequently, the average annual temperature during the near, middle, and far future periods are expected to rise by 0.26, 0.72, and 1.46 degrees celsius, respectively. rainfall data indicate that november rainfall has increased to 37.61 mm with an upward trend at the 95% confidence level, while march rainfall has decreased to 32.25 mm, also at the same confidence level.