Reducing agricultural carbon emissions is of great  practical significance to accelerate the realization of Chinas “double carbon” goal. The effect and mechanism of agricultural land scale management on agricultural carbon emissions were investigated, by using panel fixed effect model and intermediary effect model, and the inter provincial panel data from 2000 to 2022, and meanwhile the regional heterogeneity was analyzed. The results show that a 1% increase in the scale of agricultural land operations would result in a 0.01% reduction in agricultural carbon emissions. The mechanism lies in the fact that the scale of farmland operations works through three mediating variables such as agrochemical input intensity, agricultural technological progress and cropping structure. In specific, for every 1% increase in the scale of agricultural land management, the intensity of agricultural chemical inputs will decrease by 0.06%, agricultural technological progress will increase by 0.69%, and the planting structure will show a “grain oriented” trend. These changes are conducive to agricultural carbon reduction. By region, the expansion of the scale of agricultural land management will significantly reduce agricultural carbon emissions in the eastern and northeastern regions, but will raise agricultural carbon emissions in the western region. Thus, to promote the lowcarbon development of agriculture in China, it is necessary to guide agricultural producers to appropriately expand the scale of agricultural land management, reduce fertilizer use and adopt lowcarbon production technologies.

减少农业碳排放对于加快促进我国“双碳”目标的实现具有重要现实意义。利用固定效应模型、中介效应模型，采用2000—2022年省际面板数据，考察农地规模经营对农业碳排放的影响效应与作用机制，并进行地区异质性分析。研究发现：农地经营规模每扩大1%，农业的碳排放量将减少0.01%。其机制在于，农地经营规模通过农用化学品投入强度、农业技术进步、种植结构这三个中介变量来发挥作用。具体而言，农地经营规模每扩大1%，农用化学品投入强度将降低0.06%、农业技术进步增加0.69%、种植结构则呈“趋粮化”，而且这些变化有利于农业碳减排。分地区来看，农地经营规模扩大会显著降低东部地区、东北地区的农业碳排放，但会提升西部地区的农业碳排放。由此，促进我国农业低碳发展，要引导农业生产者适当扩大农地经营规模，降低化肥用量和采纳低碳生产技术。