Variation of plant communities along an elevation gradient in the Guandi Mountains, North China

摘要

The relationship between plant communities and elevation in the Guandi mountainous area was studied. Data from 89 sampling units, each of 10 m X 20 m size, taken along an elevation gradient were analyzed by TW1NSPAN. DECORANA and diversity and evenness indices. The samples were clustered into 23 groups by TW1NSPAN. representing 23 vegetation types. The composition and distribution of communities varied greatly along the altitude gradient, suggesting that community diversity is closely related to elevation in the Guandi Mountains. This is due to the change of temperature and water-conditions along the elevation gradient. Species heterogeneity and evenness were significantly correlated with elevation along the entire gradient, but showing first a trend of increases and then decreases, corresponding to the hypothesis of maximum diversity at medium elevation. Species richness varied greatly in the study area, and was not significantly correlated with elevation.