Projecting the Potential Shift of Larix principis-rupprechtii in Response to Future Climate Change: A Regional Analysis of the Haihe Basin in Northern China

Projections of species distribution shifts induced by climate change are essential for adaptive management, yet regional-scale projections that explicitly address uncertainty remain underexplored. Future habitat suitability for Larix principis-rupprechtii in the Haihe Basin is projected using ensemble MaxEnt analysis driven by 13 CMIP6 climate simulations under contrasting emission scenarios (SSP1-2.6 and SSP5-8.5). The MaxEnt demonstrates strong performance, with a mean AUC of 0.874. Future scenarios show that climatically favorable habitat for larch expands by over 20% and shifts approximately 42 km southwestward relative to the baseline, while high-suitability areas increase by 109%–181%. However, substantial uncertainty, quantified by the coefficient of variation (CV), persists in the low-suitability areas and intensifies with longer time horizons and higher emission pathways. Crucially, local topographic heterogeneity (elevation, slope, and shallow soil moisture) explains over 84% of the distribution variance, overriding broad-scale climatic drivers. We conclude that adaptive revegetation strategies at the regional basin scale should prioritize topographic controls, while the uncertainty in habitat suitability induced by climate change must not be overlooked.