Study on the driving mechanism of cultivated land change in the urban–rural fringe with Bayesian network modeling

Urbanisation accentuates human-land conflicts in the urban-rural fringe and poses significant threats to the preservation of cultivated land. Understanding the characteristics and mechanisms of cultivated land change is essential for balancing development and conservation in these regions. Based on the essential characteristics of the urban-rural fringe, a multidimensional feature index identification model suitable for long-term definition of the urban-rural fringe was developed. This model was used to identify the urban-rural fringe of Nanchang City from 2000 to 2024. A change trajectory analysis was utilized to describe the spatialtemporal pattern evolution of cultivated land, while a Bayesian network model was employed to uncover the underlying driving mechanisms. The results indicate the following: (1) The model demonstrated favourable feasibility and efficiency in the long-term sequential identification of urban-rural fringe areas. It delineated the extent of the urban-rural fringe in Nanchang City over the period from 2000 to 2024, and subsequent validation confirmed that the identification results are highly consistent with the fundamental characteristics of the urban-rural fringe; (2) In the urban-rural fringe, the total area of farmland transferred out exceeds that transferred in. Farmland transferred out is primarily converted into construction land. The transfer of farmland outwards is concentrated around the city centre and exhibits a relatively intense trend of gradual outward expansion. In contrast, the transfer of farmland inwards is more scattered and limited in spatial distribution, with farmland fragmentation becoming increasingly apparent; (3) The results of the sensitivity analysis indicate that the primary factor influencing changes in cultivated land use in the urban-rural fringe area of Nanchang City is construction occupation, followed by ecological occupation, the protective effect of policies and planning, and the degree of socioeconomic impact. These findings align with the actual development patterns observed in the urban-rural fringe area. The research results can not only directly provide policy references for the coordinated development of the urban-rural fringe and the protection of cultivated land in Nanchang City, but also offer useful references for the protection of cultivated land in similar urban-rural fringe areas.