Evolution of the potential suitable habitat of Haloxylon ammodendron in northwestern China under climate change, desert-unit differences, and identification of priority areas for conservation and restoration

Haloxylon ammodendron is an important dominant species and sand-fixing plant in the desert ecosystems of Northwest China. To assess climate-driven changes in its potentially suitable habitat, we integrated natural occurrence records from field surveys and public databases, developed an ensemble of eight algorithms in biomod2, and projected current and future suitability using three global climate models. The ensemble model achieved mean AUC and TSS values of 0.950 and 0.763, respectively, with precipitation and minimum winter temperature identified as the principal climatic drivers. Currently, potentially suitable habitat accounts for 3.97% of the study area and is projected to increase to 6.36%–11.85%, primarily through an expansion of low-suitability habitat. Responses differed markedly among the eight deserts. Expansion was greatest in the Tengger and Qaidam deserts, whereas the Taklimakan and Kumtag deserts remained predominantly unsuitable. Threshold-sensitivity and environmental-novelty analyses supported the overall expansion trend. Core conservation and priority restoration areas accounted for 0.70% and 3.23% of the study area, respectively. These findings provide a spatial basis for the conservation and climate-adaptive restoration of H. ammodendron across the eight deserts and their surrounding regions.