Unraveling the Spatiotemporal Dynamics and Nonlinear Drivers of Green Transition of Farmland Use in Major Grain‐Producing Areas: A Case Study of Jiangsu Province, China

ABSTRACT Promoting the green transition of farmland use (GTFU) in major grain‐producing areas is essential for ensuring food security and advancing sustainable agricultural development. However, existing studies on GTFU have predominantly relied on static cross‐sectional analyses, with insufficient attention paid to its nonlinear driving mechanisms. To address these gaps, this study developed a county‐level GTFU evaluation system for Jiangsu Province based on a “spatial transition–functional transition–mode transition” framework. The entropy weight method, standard deviation ellipse analysis, and Markov chain analysis were used to quantify and characterize the spatiotemporal evolution of GTFU from 2006 to 2022. Furthermore, machine learning models were integrated with SHapley Additive exPlanations (SHAP) to reveal the nonlinear effects and interactions of socioeconomic and environmental drivers. The results showed that GTFU in Jiangsu Province generally improved over the study period, with high levels concentrated in northern Jiangsu and low levels observed in southern Jiangsu. Pronounced spatial imbalance persisted across the province, and after 2010, spatial disparity in GTFU along the northwest–southeast direction widened slightly. Transitions among GTFU classes exhibited strong path dependence, while counties adjacent to regions with higher GTFU levels benefited from positive spatial spillover effects. Socioeconomic drivers exerted a stronger influence on GTFU than environmental drivers. Among the dominant drivers, population density and the degree of non‐grain conversion of cultivated land showed threshold effects at 0.68 persons per 0.1 ha and 0.24, respectively, initially promoting GTFU and then inhibiting it. By contrast, agricultural industrial structure, mechanization, and technological innovation displayed the opposite nonlinear pattern. Notably, topographic conditions and cultivated land fragmentation exhibited more complex nonlinear effects. Interactions among driving factors also played an important role in shaping GTFU. These findings provide valuable insights for policymakers seeking to promote GTFU in Jiangsu Province and other similar major grain‐producing regions.