Pathways to agricultural carbon sequestration and emission reduction and food security synergy in Hunan China

Under intensifying climate warming and rising food demand, balancing low-carbon agricultural transformation with food security is urgent for China's carbon peaking and carbon neutrality goals. Focusing on Hunan Province, a major grain-producing region, this study measures coordination between carbon sequestration and emission reduction in agricultural cultivation and food security across prefecture-level cities from 2000 to 2023 using an improved coupling coordination degree model, and identifies driving pathways through a partial least squares structural equation model incorporating temporal and spatial lag effects. Coordination showed early heterogeneity but rose overall after 2011, with high-value areas shifting from scattered points to contiguous clusters. Agricultural policy was the strongest driver, acting directly and through economic benefits, technological improvement, and production conditions. Spatial spillover effects remained significant but weakened over time. These findings support differentiated local policies that jointly advance agricultural emission reduction, carbon sequestration, and food security.