Figure 1

Plotted alpha (α), beta (β) and gamma (ɣ) diversity against elevation. The diversity indexes are estimated by an additive partitioning of species diversity (ɣ = β + α) with gamma being the total diversity, beta the among-site diversity (average amount of diversity not found in a single site), and alpha the average within-site diversity (as described in Lu et al.⁷¹). Linear regressions of observed α, β and ɣ diversity against elevation revealed statistically significant relationships for two indexes, the β and ɣ diversities (β: adjusted R² = 0.1638, P = 0.0138; ɣ: adjusted R² = 0.1706, P = 0.0121); the correlation between elevation and α diversity was not significant (adjusted R² = 0.0061, P = 0.2856).