Examining governance strategies for the non-grainization of mountain valley paddy fields in Southern China under the conflict-coordination-adaptation framework

Shanlongtian (mountain valley paddy fields, MVPF), characterized by their enclosed topography surrounded by mountains on three sides, represent critical challenges in non-grain production governance across Southern China. Given their vast quantity, widespread distribution, and fragmented patches, effective restoration requires adherence to principles of precise identification, scientific diagnosis, and differentiated strategies. This study constructed a "conflict-coordination-adaptation" framework, selecting Jianyang district in Fujian province as a typical southern mountainous case. We first mapped the spatial distribution and utilization status of Shanlongtian, then employed self-organizing mapping network analysis and random forest methods to diagnose elemental conflicts in grain production and drivers of non-grain conversion. Finally, remediation zones were delineated based on projected remediation benefits for 2035 and 2050, with corresponding strategies proposed. Key findings include: (1) Jianyang's croplands exhibit dendritic patterns, with 33% classified as Shanlongtian (predominantly at "branch tips"), of which 36.5% are converted to grapes, citrus, and tea plantations. (2) Conflict analysis revealed a hierarchy of "natural constraints (49.72%)>ecological pressures (25.47%)> socioeconomic factors (24.79%)", with wildlife disturbances, distance to rural settlements, and drainage conditions identified as dominant drivers. (3) Based on the multi-level zoning, the proportion of "non-grain" MVPFs allocated to coordination remediation zones is projected to be 55.85% by 2035 and 61.49% by 2050, with estimated remediation benefits of 113 million and 288 million yuan, respectively. This research offered a methodological framework for implementing the "Three Batches" policy in China's southern mountainous regions. It guided the adaptive restoration of grain production through spatially targeted strategies, ensuring the avoidance of excessive investment and ineffective governance efforts.