Mapping Soil Organic Carbon Research in Conservation Agriculture: A Systematic Review

Conservation agriculture (CA) increases soil organic carbon (SOC) and supports sustainable agricultural systems. Despite extensive research, the evidence remains fragmented regarding research hotspots, assessment methods, and specific soil C fractions affected by CA practices. Here we conduct a bibliometric analysis of 4,256 publications published between 2016 and 2025 to reveal global research trends, thematic evolution, and emerging priorities at the intersection of SOC and CA. Results show rapid growth in scientific output, with China, the United States, and the European Union forming the core of global collaboration networks. Our analysis highlights a shifting research focus from conventional tillage and climate impact assessments toward soil biodiversity, microbiome interactions, and ecosystem resilience. Methodologically, the synergy between machine learning (ML) and remote sensing (RS) has transformed SOC monitoring into a robust data-driven science. Future research trends may concentrate on the under-exploration of soil inorganic carbon (SIC) and the extremely sensitive labile pools, which include quickly oxidizable carbon. Furthermore, bridging the gap between scientific evidence, farm-level feasibility, and policy support remains critical. Future efforts should prioritize geographically inclusive and socio-ecological assessments, alongside harmonized frameworks, to support scalable CA-based SOC management. • Mapped global SOC research under conservation agriculture by bibliometric analysis (4,256 publications). • Research hotspots shifted toward microbes and resilience. • Machine learning and remote sensing improved SOC monitoring. • SIC and labile carbon remain understudied.