Does the cropping system have a substantial influence on greenhouse gas emissions? Dynamics and key factors-based insights from an empirical study of China

Different cropping systems exhibit significant variations in greenhouse gas (GHG) emissions. Understanding the GHG emission performance of these systems is conducive to the scientific allocation of emission reduction responsibilities. However, comprehensive investigations into the spatiotemporal dynamics and underlying causes of GHG emissions in major cropping systems across entire regions remain limited. Based on the classification of seven cropping systems in China, this study calculates their GHG emissions from 2000 to 2020. The Logarithmic Mean Divisia Index (LMDI) method is employed to decompose the factors driving changes in GHG emissions from various cropping systems at the provincial level. The results indicate that double rice and single rice were the largest contributors to GHG emissions in staple food production, accounting for over half of the total emissions. Notably, GHG emissions from double rice have decreased significantly, particularly in South China, where reductions exceeded 30 %. The agricultural economy, planting structure, land area per unit of agricultural GDP (AGDP), and agricultural labor structure are the dominant factors influencing fluctuations in GHG emissions from multiple cropping systems, exhibiting distinct spatiotemporal heterogeneity. This study identifies spatial differences in GHG emissions and their influencing factors among different cropping systems, highlighting the need for region-specific management strategies. The findings provide valuable decision-making support for formulating targeted GHG emission control strategies in regional food production.