Potential dynamic changes of single-season rice planting suitability across China

As an important food crop in China, changes in suitable areas for rice planting are critical to agricultural production. In this study, the maximum entropy model (MaxEnt) was utilized to pick the main climatic factors affecting single-season rice planting distribution and project the potential changes under RCP4.5 and RCP8.5 scenarios. It was clear that rice planting distribution was significantly affected by annual total precipitation, the accumulated temperature during a period in which daily temperature was ≥ 10 °C, the moisture index, total precipitation during April-September, and continuous days during the period of daily temperature ≥ 18 °C, with their contribution being 97.6%. There was a continuous decrease in the area of good and high suitability for rice planting projected from 2021-2040 to 2061-2080, with a respective value ranging from 1.49 × 10⁶ km² to 0.93 × 10⁶ km² under the RCP4.5 scenario and from 1.42 × 10⁶ km² to 0.66 × 10⁶ km² under RCP8.5 scenarios. In 2081-2100, there was a bit increase in the area of good and high suitability under the RCP4.5 scenario. The most significant increases in good and high suitability were detected in Northeast China, while obvious decreases were demonstrated in the Yangtze River Basin which might be exposed to extreme temperature threat. The spatial potential planting center was characterized by the largest planting area in 25°N-37°N and 98°E-134°E. The north boundary and center of rice cultivation arose to 53.5°N and 37.52°N, respectively. These potential distributions for single-season rice under future climate change can provide a theoretical basis for optimizing rice planting layout, improving cultivation, and adjusting variety and management systems in response to climate change.