Regional differences and convergence of agricultural carbon efficiency in China: Embodying carbon sink effect

• We incorporate agricultural carbon emissions and carbon sinks into the ACE accounting system, and re-measure the ACE. • Disregarding agricultural carbon sinks will lead to underestimating ACE. • The convergence speed of ACE at the national level has increased significantly after the proposed carbon emissions trading pilot policy. Exploring the distributional dynamics, regional differences, and convergence characteristics of China’s agricultural carbon efficiency (ACE) is significant for promoting the low-carbon agriculture development in China and mitigating global climate change. We incorporate agricultural carbon emissions and carbon sinks into the ACE accounting system, re-measure the ACE of China’s 31 provinces from 2000 to 2021, and focus on ACE’s dynamic evolution law, regional differences, and convergence mechanism in the three major grain functional areas. The study finds that: (1) Disregarding agricultural carbon sinks will lead to underestimating ACE. The overall ACE of the whole country and the three major grain functional areas shows an upward trend. The main grain-producing areas have the fastest growth in ACE, and the main grain-marketing areas have the highest average ACE levels. (2) The gap between groups in ACE in the three major grain functional areas has been narrowing, and hypervariable density contributes the most to the overall gap in ACE. (3) ACE suffers from σ -convergence, both absolute β -convergence and conditional β -convergence, at the national level and within the three major food functional regions. The impacts of urbanization level, aging of the rural labor force, farmers’ education level, agricultural science and technology innovation, regional industrial structure of agriculture, and agricultural disaster rate on ACE are regionally heterogeneous. (4) The convergence speed of ACE at the national level has increased significantly after the proposed carbon emissions trading pilot policy. We suggest strengthening the intra-regional balance and reducing the intra-regional ACE gap. Policymakers should accurately formulate and implement agricultural carbon efficiency improvement policies according to the convergence mechanisms of different regions. We should actively develop agricultural carbon trading products and give full play to their role in improving ACE.