【摘要】 【目的】探明内蒙古不同地区主要农作物秸秆养分资源量及其替代化肥潜力，为作物秸秆的合理利用和化肥减施提供参考。【方法】基于2019—2021年统计数据和文献资料，采用草谷比法估算内蒙古各盟市主要农作物（玉米、小麦、大豆、向日葵）秸秆产量和养分资源量，并计算单位播种面积不同农作物秸秆全量还田后的化肥替代潜力。【结果】2019—2021年内蒙古主要农作物秸秆年均总产量达4 700.72万t，其中，玉米、小麦、大豆、向日葵秸秆年均产量分别为3 806.67万t、194.07万t、314.65万t和385.33万t；主要农作物秸秆年均氮（N）、磷（P₂O₅）、钾（K₂O）养分资源量分别为45.14万t、15.99万t、69.52万t，其中，玉米秸秆养分资源主要分布在通辽市（28.62%）、兴安盟（17.73%）、赤峰市（15.68%）；小麦秸秆养分资源主要分布在呼伦贝尔市（49.02%）和巴彦淖尔市（18.38%）；大豆秸秆养分资源主要分布在呼伦贝尔市（79.37%）；向日葵秸秆养分资源主要分布在巴彦淖尔市（59.94%）。农作物秸秆全量还田后单位播种面积的玉米秸秆当季化肥替代潜力为N 25.81～55.66 kg/hm²、P2O5 13.12～28.21 kg/hm²、K2O 62.53～135.34 kg/hm²；小麦秸秆当季化肥替代潜力为N 7.45～25.96 kg/hm²、P2O5 2.63～10.71 kg/hm²、K2O 25.88～76.90 kg/hm²；大豆秸秆当季化肥替代潜力为N 7.97～31.81 kg/hm²、P2O5 3.96～11.08 kg/hm²、K2O 12.91～36.48 kg/hm²；向日葵秸秆当季化肥替代潜力为P₂O₅ 3.86～13.19 kg/hm²、K₂O 38.79～134.93 kg/hm²。各地区农作物秸秆全量还田后的当季替代化肥潜力存在明显差异，单位播种面积玉米、小麦、向日葵秸秆还田替代化肥潜力以阿拉善盟最大，大豆秸秆还田替代化肥潜力以巴彦淖尔市最大。【结论】内蒙古主要农作物秸秆养分资源丰富，化肥替代潜力较大。不同地区农作物秸秆全量还田后的当季替代化肥潜力存在明显差异，应因地制宜加大秸秆资源的还田利用，以提高秸秆养分资源利用效率，实现化肥减施，促进农业绿色高效发展。更多还原

【Abstract】 【Objective】The nutrient resources quantity of straw from main crops in different regions of Inner Mongolia and the potential to replace chemical fertilizers were studied to provide a reference for the rational utilization of crop straw and the reduction of fertilizer application. 【Method】Based on the statistical data from 2019 to 2021 and literature sources, the straw yield and nutrient resources of major crops（maize, wheat, soybean, sunflower） in various leagues and cities of Inner Mongolia were estimated using the grass-to-cereal ratio method. The fertilizer substitution potential after full straw return for different crops per unit of sown area was also calculated.【Result】From 2019 to 2021,the average annual total yield of crop straw in Inner Mongolia was 47.007 2 million tons, among which the amounts of straw from maize, wheat, soybean and sunflower were 38.066 7 million, 1.940 7 million, 3.146 5 million and 3.853 3 million tons respectively. The average annual nutrients [nitrogen（N）, phosphorus（P₂O₅）, potassium（K₂O）] in the straw were 0.451 4million, 0.159 9 million, 0.695 2 million tons respectively. Specifically, the straw nutrients of maize were mainly distributed in Tongliao City（28.62%）, Hinggan League（17.73%）, and Chifeng City（15.68%）, respectively. The straw nutrients of wheat were primarily distributed in Hulun Buir City（49.02%） and Bayannur City（18.38%）. The straw nutrients of soybean were largely distributed in Hulun Buir City（79.37%）, while the straw nutrients of sunflower were mostly in Bayannur City（59.94%）. In terms of the total straw returned to the fields, the potential of chemical fertilizers substituted by straw from maize was N 25.81-55.66 kg/hm², P₂O₅ 13.12-28.21 kg/hm², and K₂O 62.53-135.34 kg/hm². For wheat straw were N7.45-25.96 kg/hm², P₂O₅ 2.63-10.71 kg/hm², and K₂O 25.88-76.90 kg/hm². For soybean straw, values were N 7.97-31.81 kg/hm², P₂O₅ 3.96-11.08 kg/hm², and K₂O 12.91-36.48 kg/hm². Lastly, for sunflower straw were P₂O₅ 3.86-13.19kg/hm² and K₂O 38.79-134.93 kg/hm². There were significant differences in the fertilizer substitution potential in the current season after full straw return in different regions. The fertilizer substitution potential for maize, wheat, and sunflower straw return per unit of sown area in Alagxa League was the greatest, while that for soybean straw return per unit of sown area in Bayannur City was the greatest.【Conclusion】In Inner Mongolia, the nutrient resources of crop straw are abundant, with significant potential for fertilizer substitution. The fertilizer substitution potential of straw from different crops after returning in season are significant different in different regions. It is suggested to increase the return and utilization of straw resources according to different situations of regions, so that to improve the utilization efficiency of straw nutrient resource, reduce fertilizer application, and promote the green and efficient development of agriculture.更多还原