A Topology-Aware Multitemporal Framework for Settlement Expansion and Morphological Reconfiguration in Mountainous Traditional Villages

New construction reconfigures settlement morphology through distinct spatial and topological pathways, yet existing studies often use single-time-point analyses. Using multi-source imagery from 1972, 2008, and 2024, this study aims to identify these pathways and trace their evolution across 26 nationally listed traditional villages in the Zhuozhang River Basin, China. Our topology-aware multitemporal framework integrates parameterized settlement-boundary delineation, Python classification, and indicators of pathway composition and reconfiguration. Unlike location-based classification, it distinguishes inter-component bridging from intra-component cavity closure. Results: (1) Newly appearing footprint objects were assigned to four modes of morphological reconfiguration: intra-boundary infill (PI), which restructures the internal fabric; bridge-mediated consolidation (PB), which reorganizes connectivity and internal voids; connected fringe growth (PF), which reshapes and extends settlement boundaries; and detached external growth (PD), which increases spatial detachment through isolated patches. (2) PF remained dominant, but its area share declined from 71.9% to 53.4%, indicating a shift from fringe-oriented expansion toward more varied combinations of internal, bridging, and detached reconfiguration. (3) Between-village compositional dispersion increased from 0.235 to 0.492, while dominant-mode diversity rose from 0.118 to 0.706, indicating increasingly differentiated growth pathways rather than a common regional trajectory. The framework supports village-scale conservation screening, topological assessment, and differentiated management of fringe and detached expansion.