Impact of road density on the coupling of forest resilience and fragmentation

Road construction profoundly affects forest landscapes, but its impact on the coupling between forest resilience and fragmentation remains underexplored. Thus, we calculated kernel density estimation (KDE) as an indicator of road density and quantified spatiotemporal dynamics of forest resilience and fragmentation in China from 2010 to 2020. We further examined how road density influences the coupling between forest resilience and fragmentation. Results showed that: (1) Forest resilience increased nationally, and fragmentation declined in most regions. (2) Bivariate spatial autocorrelation between coupling dynamics and KDE revealed high–high clusters in the Yangtze and Pearl River Deltas, and low–low in Daxinganling and southwestern Tibet. (3) SHapley Additive exPlanations showed that high KDE contributed positively and low KDE contributed negatively to coupling dynamics; multiscale geographically weighted regression revealed stronger synergistic effects in the pan-south and weaker in the northeast. This study offers quantitative insights into sustainable road planning and supports ecological restoration strategies.