Suitability Analysis of Rice Cropping Patterns in China Based on MaxEnt Model

Climate warming is reshaping hydrothermal resource allocation worldwide, thereby altering the spatial suitability patterns of rice under different cropping systems. Using the maximum entropy model (MaxEnt), this study characterizes the climatic niche features of four typical rice cropping systems in China—single-season rice, double-season rice, rice–wheat rotation, and rice–maize rotation—based on occurrence points and climatic variables, and evaluates changes in their potential suitable areas during 2081–2100 under the SSP2-4.5 and SSP5-8.5 scenarios. The results show marked differences in the dominant factors controlling the four systems. Single-season rice and rice–maize rotation are mainly constrained by heat accumulation, whereas the suitability boundary of double-season rice is jointly limited by extreme temperature thresholds and precipitation conditions. Rice–wheat rotation is more sensitive to annual temperature range, reflecting its dependence on the seasonal rhythm of cold winters and hot summers. Under future climate scenarios, the potential suitable areas of all four systems generally shift northward and expand eastward, with stronger changes under SSP5-8.5. Suitability increases in parts of Northeast and North China, suggesting theoretical potential for the development of double-cropping systems in these regions, whereas some traditional double-season rice areas in South China may face declining suitability because of increasing high-temperature risk. These findings provide a reference for adjusting cropping systems and enhancing regional adaptation under climate change.