Objectives To elucidate the patterns of vertical vegetation distribution and the characteristics of species diversity in the Dongdashan–Lawushan region of the middle Lancang River Basin, and to construct a schematic map of plant community distribution, thereby providing scientific support for the restoration of degraded ecosystems in this area.

Method Based on field surveys conducted along an altitudinal gradient, we classified the major plant community types using species importance values and the principles of vegetation floristic division. Community composition, species richness, and alpha diversity were selected as the main evaluation indicators to analyze the patterns of vertical vegetation distribution and their responses to the elevational gradient.

Result A total of 249 vascular plant species were recorded in the survey, belonging to 61 families and 154 genera. The dominant families were Asteraceae, Rosaceae, and Fabaceae, with perennial herbs and shrubs as the dominant life forms. Significant differences were observed in the vertical vegetation zonation between the eastern and western slopes, and eight vertical belts were identified in total, which reflects the transitional characteristics of the vegetation structure between the Hengduan Mountains and the South China Floristic Subregion. The diversity of different plant life forms showed regular variations along the altitudinal gradient: the species richness and Shannon-Wiener index of the tree layer followed a unimodal pattern, peaking in the subalpine dark coniferous forest zone (around 3850 m a.s.l.); the diversity of the shrub and herb layers also exhibited a unimodal pattern, with peaks occurring in the middle-elevation areas with more favorable hydrothermal conditions; the Pielou evenness index of the tree layer decreased continuously with increasing elevation, while no consistent variation trend was found for the shrub and herb layers.

Conclusion This study preliminarily clarifies the vertical patterns of plant diversity in the study area of the Hengduan Mountains. The results provide important references for the restoration of degraded local ecosystems: on the one hand, they help identify potential target communities and key species for vegetation restoration at different elevations; on the other hand, this research offers a direct basis for the rational configuration and near-natural restoration of tree-shrub-herb assemblages along different altitudinal gradients, thereby supporting differentiated and refined ecological restoration practices.