基于常德市416份农户调查数据，采用Tobit模型分析经营规模对农户耕地碳生产率的影响。研究发现：农户耕地碳生产率会随着经营规模的扩大呈“倒U形”变化，拐点为3.929 hm2，小于耕地生产率最大化下的经营规模拐点值（4.128 hm2）；Ⅰ兼农户和Ⅱ兼农户的经营规模与耕地碳生产率依然呈“倒U形”关系，而非农户的经营规模与耕地碳生产率则呈显著的正相关关系；农业收入占比和集镇距离对耕地碳生产率有显著正向影响，耕地细碎化程度对耕地碳生产率有显著负向影响。据此，在推进耕地适度规模经营时，可将考虑碳排放和不考虑碳排放的最适经营规模作为下限值和上限值，提高耕地碳生产率，促进农业低碳绿色转型升级。

Based on the survey data of 416 farmers in Changde City, the impact of operation scale on the carbon productivity of farmers’ cultivated land has been analyzed by using Tobit model. The study shows that with the expansion of the operation scale, the carbon productivity of farmers’ cultivated land changes in an “inverted U-shape curve”, with an inflection point of 3.929 hm2, which is less than the inflection point of 4.128 hm2 for the operation scale with maximization of cultivated land productivity. The relationship between operation scale and carbon productivity of cultivated land for Type I and Type II farmers remains an “inverted U-shape curve” while that for non-farmers is significantly positive. The proportion of agricultural income and the distance between the market towns have a significantly positive effect on the carbon productivity of farmers’ cultivated land while the degree of cultivated land fragmentation has a significantly negative effect. Therefore, for boosting the appropriate scale management of cultivated land, the optimal operating scale with and without carbon emissions can be taken as the lower and upper limits respectively, so as to improve carbon productivity of cultivated land and promote transformation and upgrading of low-carbon green agriculture.

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国家自然科学基金项目（41801190）；湖南省哲学社会科学基金项目（18YBQ097）；湖南省教育厅重点项目（22A0066）；湖南省自然资源科研项目（2022-33）