Studying the altitude distribution pattern and driving factors of plant community diversity in subalpine meadow is helpful to reveal the mechanism of plant community species coexistence and diversity maintenance under the background of coastal elevation gradient. In this study， the plant community in Gongnaisi mountain area was taken as the research object， and the distribution law of plant community diversity along the elevation gradient and environmental influencing factors were discussed to reveal the plant community construction mechanism in this area. The results showed that： （1） With increasing the altitude， Pielou index， Simpson index， Shannon-Wiener index， Functional Evenness Index （FEVE）， Functional Divergence Index （FDIS） and Rao’s second entropy index all showed a single-peak change pattern， and the system development structure changed from divergence to aggregation； （2） PD index was significantly positively correlated with species richness and Margalef index， and positively correlated with Pielou index and Rao second entropy index. In addition， except FDis， there was a positive correlation between species richness index and functional diversity index； （3） Community diversity was mainly affected by environmental factors such as soil organic matter， total nitrogen， pH， average annual temperature， average annual precipitation and soil moisture. The plant community diversity in Gongnaisi subalpine meadow changed regularly along the elevation gradient， and its distribution pattern was mainly driven by environmental factors such as soil organic matter， total nitrogen， pH， annual average temperature， soil moisture content and annual average precipitation.

Functional diversity  /  Phylogenetic diversity  /  Phylogenetic structure  /  Environmental factors  /  Subalpine meadow