Assessing rice yield responses to climate change scenarios using a crop simulation model

Climate change is considered one of the most significant global environmental challenges of the future, and it is expected to adversely affect crop production. Rice is one of the most widely consumed staple foods in the world. Crop simulation models are tools that help researchers to simulate crop production stages for the future at the selected regions. The aim of this study was to evaluate the accuracy of the DSSAT (Decision Support System for Agrotechnology Transfer) CERES (Crop Environment Resource Synthesis) Rice (DSSAT-CERES-Rice) crop simulation model during its calibration and validation stages, and to assess the impacts of climate change in the Mediterranean region of Türkiye. In the calibration stage, the results showed that the estimated phenological values were within an acceptable range, with an error percentage below 10%. The simulated and observed leaf area index (LAI) showed good agreement with normalized root mean square error (nRMSE) ranging from 17.40% to 28.44% and Willmott's d-index values of 0.59-0.79. Similarly, biomass simulations were consistent with observations (nRMSE: 5.60-18.52%) with satisfactory d-index values, except under I_1.50 treatment. Climate change scenarios indicated that average yields under irrigated conditions increased by up to 10% in the late-future period, while rainfed conditions showed decreases of 15-25% due to higher temperatures and shortened growth duration. The findings highlight that the crop simulation model offers a robust framework for evaluating the impacts of climate change and guiding the development of effective adaptation strategies.