Farmland ecosystems represent a vital carbon source and sink within terrestrial ecosystems. The investigation into the characteristics of carbon emissions and their influencing factors within farmland ecosystems is crucial for the realization of carbon reduction and the promotion of low-carbon development. This study leveraged the analytical prowess of CiteSpace software (version 6.1.5) to examine a comprehensive body of 2805 scholarly works related to carbon emissions within agricultural ecosystems, as documented in the Web of Science Core Database from 1991 through to 2023. Through a visual dissection of data based on national, institutional, and thematic dimensions, the study elucidated emergent focal points and evolving trajectories within this scholarly domain. The findings revealed that current scholarly discussions on carbon emissions from agricultural lands have primarily focused on three key areas: the factors that influence these emissions, the possibilities for their reduction, and the subsequent environmental impacts. Focal points of research have predominantly centered on four key themes: “greenhouse gas emissions from farmland ecosystems”, “carbon emission models for farmland ecosystems”, ”carbon sequestration in farmland ecosystems”, and ”sustainable development in agricultural ecosystems”. The academic perspective has gradually shifted from a broad overview of carbon emissions towards a detailed examination of the determinants of emissions and the efficiency of agricultural resource utilization. Looking forward, it is crucial to explore the mechanisms behind high-carbon agricultural practices and to establish their optimal operational thresholds. The focus of research is shifting from macro carbon emissions to the analysis of emission factors and the efficiency of agricultural input use. Future efforts should emphasize exploring the mechanisms of the environmental impacts caused by high-carbon agricultural inputs and the optimal input levels, refining emission reduction methods in agricultural ecosystems, and promoting collaboration and exchange among researchers worldwide.