What drives the spatiotemporal evolution of land use conflicts? Evidence of threshold effects from 19 Chinese urban agglomerations

Land-use conflicts (LUCs) have emerged as a critical constraint on regional sustainable development. However, existing research has predominantly focused on single-dimensional conflict identification, with limited attention to systematic comparative analyses and comprehensive assessments, particularly at the scale of urban agglomerations. In this study, we used multi-source data from 19 urban agglomerations in China from 2000 to 2020 to construct a land-use conflict assessment framework integrating structural and functional dimensions. By combining spatial Durbin models, machine learning, and generalized additive models, we examined the spatiotemporal evolution and driving mechanisms of LUCs. The results showed that LUCs followed a phased trajectory of initial intensification followed by subsequent alleviation, increasing significantly during 2000–2010 and gradually easing after 2010 alongside ecological restoration and regional revitalization strategies. Spatially, LUCs exhibited a clear east–high, west–low pattern. The human footprint index (HFI), terrain roughness index (TRI), and normalized difference vegetation index (NDVI) were the dominant drivers, although their effects varied across regions. LUCs in eastern urban agglomerations were primarily associated with high-intensity development pressure, whereas those in northwestern regions were more constrained by topographic conditions. Moreover, key drivers exhibited significant threshold effects: HFI positively intensified LUCs, TRI demonstrated an increasingly inhibitory effect, and NDVI exerted a nonmonotonic influence, with the strongest ecological–development conflict occurring under intermediate vegetation cover. These findings deepen the understanding of LUC dynamics and provide important implications for territorial spatial planning, coordinated regional development, and sustainable transitions in rapidly urbanizing regions, particularly in the Global South.