在人口增长与生态系统和资源约束压力叠加的背景下，如何在保障粮食安全的同时实现环境的可持续性已成为全球发展命题。在省域尺度上计算了全国3种主粮作物生产过程中水、能消耗和碳排放情况，探究了各投入要素在不同区域的相对贡献，评估了各区域的作物热量生产力，结果表明：小麦、水稻、玉米单位热量的水足迹分别为134、209、83 kg/Mcal，能量投入分别为1 375、848、868 kJ/Mcal，碳足迹分别为191、408、121 g CO2 eq/Mcal；氮肥生产和灌溉水是区域生产效率差异的主要驱动因素，二者在能量投入差异中的总贡献率为39.4%~68.1%；东北地区热量生产力最高，其次为华中和华北地区，华南地区最低。从降低投入、产出更多热量的角度出发，可适当向东北地区转移种植规模，缓解中国的资源短缺和环境问题，并保障粮食安全。
英文摘要:
Under the combined pressures of population growth, ecosystem stress and resource limitations, how to ensure food security while advancing environmental sustainability has become a global development imperative. This study calculates water, energy consumption and carbon emission for three major grain crops across China’s provinces, investigates the relative contributions of input factors to regional disparities, and evaluates regional crop caloric productivity. Key findings show that water footprints per unit calories are 134 kg/Mcal for wheat, 209 kg/Mcal for rice, and 83 kg/Mcal for maize, corresponding to 1 375, 848, and 868 kJ/Mcal of energy inputs, as well as 191, 408, and 121 g CO2 eq/Mcal of carbon footprints, respectively. Nitrogen fertilizer production and irrigation water are the primary drivers of regional disparities in production efficiency, contributing 39.4%-68.1% in total to the gap of energy input. The Northeast China exhibits the highest caloric productivity, followed by the Central and North China, while the South China demonstrates the lowest productivity. From the perspective of minimizing inputs and maximizing caloric output, it is advisable to shift a portion of crop cultivation to Northeast China. This would help ease China’s resource shortages and environmental pressures while safeguarding food security.