Suitability Analysis of Rice Cropping Patterns in China Using the MaxEnt Model

Climate warming is reshaping hydrothermal resources for rice production, but the climatic responses of different rice-based cropping systems have not been sufficiently compared. This study evaluated the climatic suitability and dominant climatic controls of four major rice cropping systems in China: single-season rice, double-season rice, rice–wheat rotation, and rice–maize rotation. Occurrence records were extracted from ChinaCP and screened using a 30 m rice distribution mask. MaxEnt models were calibrated using agroclimatic variables for the historical baseline and end-century SSP2-4.5 and SSP5-8.5 scenarios. The models showed good presence–background discrimination, with mean training AUC values of 0.868 ± 0.001, 0.959 ± 0.001, 0.969 ± 0.002, and 0.963 ± 0.003 for the four systems, respectively. Dominant climatic controls differed among systems. Single-season rice, rice–wheat rotation, and rice–maize rotation were mainly associated with heat accumulation, with temperature ≥0 °C (AT0) showing the highest permutation importance of 55.9%, 59.8%, and 77.0%, respectively. Double-season rice showed a distinct response constrained by precipitation and monthly temperature conditions, with annual precipitation contributing 69.8%. Scenario-based projections for 2081–2100 indicated a system-specific redistribution of climatic suitability, with northward increases most evident for single-season rice and rice–wheat rotation, localized changes for double-season rice, and increased suitability for rice–maize rotation mainly in Southwest and parts of South China. Changes were stronger under SSP5-8.5. These findings show that rice-based cropping systems should not be treated as a single uniform category in climate-change suitability assessments.