Prediction of the effect of climate change on wheat yield in Thrace Region

The effects of climate change have begun to be experienced intensely nowadays. Precise estimation of how crop production and/or yield will be affected by climate change is of great importance for food security. The aim of this study is to model the effect of climate change on the yield of wheat in Thrace Region. For this purpose, the 2020-2021 period wheat yield value taken from the farmer's field was calibrated by comparing it with the one calculated with the LINTUL model using the climate data of the same year and then yield values were estimated for the 2031-2040, 2041-2050, 2051-2060, 2061-2070 and 2071-2080 periods with the climate data obtained from the RCP4.5 and RCP8.5 scenarios of HadGEM2-ES and MPI-ESM-MR global climate models. Yield estimations were made in two ways without changing the sowing and harvest dates: In the first, yield calculations were made by considering the average lowest and highest temperature, solar radiation and precipitation change. In the second, while the solar radiation values were kept constant for the period 2004-2021, average minimum and maximum temperature and precipitation changes were taken into account. In the first approach, the estimated yield changes for the RCP4.5 and RCP8.5 scenarios of the HadGEM2-ES model were calculated between 1,5%-7,5% and -7,5%-7,5%, respectively, while for the MPI-ESM-MR model they were simulated between 9,0%-13,4% and 3,0%-16,4%in the same order. It was concluded that in yield estimations, the effect of solar radiation along with temperature and precipitation must be taken into account. For food security, the agricultural lands of the Thrace Region should not be used beyond their purposes since yield is forecasted to increase generally with climate change.