Climate shocks and social adaptation shaped the trajectory of prehistoric settlement in the Weihe River Basin

Understanding the long-term dynamic evolution of human-environment interactions is essential for revealing patterns of social development and ecological adaptation. This study quantitatively analyzes the nonlinear and spatially heterogeneous relationships between settlement distribution and environmental factors in the Weihe River Basin from the pre-Yangshao (9000-7000 cal BP)to the Bronze Age (4000-2500 cal BP) by Multiscale Geographically Weighted Regression (MGWR) and Multi-Layer Perceptron (MLP) models. The results show that during the pre-Yangshao period, settlements were highly clustered in the southeastern part of the basin, with MLP confirming a strong reliance on warm climate, stable water, and dense vegetation. From the Yangshao (7000-5000 cal BP) to the Longshan period (5000-4000 cal BP), societies adopted a risk-aversion diffusion strategy: average settlement elevation increased by 25.83 m, and the proportion of waterside settlements dropped from 78.9% to 33.8%. MGWR and MLP revealed that elevation and erosion intensity became dominant constraints. Notably, these trends occurred within the broader temporal window of the 4.2 ka BP climate anomaly. During the Bronze Age, settlement distribution became highly aggregated in core areas such as the Guanzhong Plain, reflecting a shift toward socio-political organization; location choices increasingly prioritized agricultural potential and strategic considerations alongside environmental suitability. By integrating MGWR and MLP, this study quantifies the shifting balance between environmental constraints and anthropogenic agency, thereby deepening our understanding of early social complexity in the Weihe River Basin.