The impact mechanism of cultivated land use transformation on the synergy of agricultural pollution reduction and carbon abatement

Cultivated land use transformation not only enhances the efficiency of land resource utilization but also serves as a critical driver of agricultural pollution reduction and carbon abatement, thereby supporting green development and ecological civilization construction. Drawing on panel data for 31 provinces in China (excluding Hong Kong, Macao, and Taiwan) from 2000 to 2023, this study constructs an integrated index system for cultivated land use transformation and an Agricultural Pollution and Carbon Reduction Synergy Index (APCR), identifies their spatial patterns, and empirically assesses the synergistic effects of cultivated land use transformation on pollution reduction and carbon abatement. The research has 5 results. ① Spatially, cultivated land use transformation exhibits a pronounced east-central-west gradient, while APCR levels have shifted from marked regional disparities toward a progressively more balanced pattern. ② Cultivated land use transformation exerts a significant positive effect on agricultural pollution-carbon reduction synergy, which is consistently supported by robustness tests and instrumental variable estimations. ③ Mechanism analysis reveals that cultivated land use transformation promotes APCR primarily through agricultural green technological innovation and enhancements in human capital. ④ Environmental governance intensity and government fiscal support strengthen the synergistic effect of cultivated land use transformation on agricultural pollution reduction and carbon abatement. ⑤ Heterogeneity analysis indicates that the effects are significant in the first and third topographic step but not in the second; stronger east of the Hu Huanyong Line than west; and significant in the Yellow River Basin but insignificant in the Yangtze River Basin. Overall, advancing cultivated land use transformation in a region-specific and security-oriented manner is essential for effectively coordinating the relationship between land use restructuring and agricultural pollution-carbon reduction synergy.