Diversity of Woodland Communities and Plant Species along an Altitudinal Gradient in the Guancen Mountains, China

Table 4

Spearman rank correlation coefficients between environmental variables and species diversity in woodland communities in the Guancen Mountains, China.

Environmental variables	Diversity indices
	Species no.	R1	H′	N2	E1	E2
Elevation	−0.567***; (𝑅^2 =0.408***)	−0.581***; (𝑅^2 =0.449***)	−0.525***; (𝑅^2 =0.378***)	−0.545***; (𝑅^2 =0.372***)	−0.489***; (𝑅^2 =0.234***)	−0.174; (𝑅^2 =0.032)
Slope	0.398 **	0.462 ***	0.458 ***	0.391 **	0.362 **	0.175
Slope aspect	−0.526 ***	−0.499 ***	−0.499 ***	−0.461 ***	−0.398 **	−0.110
Litter thickness	−0.471***	−0.512***	−0.577***	−0.597***	−0.523***	−0.211

* 𝑃<0.05, **𝑃<0.01, ***𝑃<0.001;𝑅² in brackets refers to the significance of unimodal regression; R1: Margalef richness index; H′: Shannon-Wiener heterogeneity index; N2: Hill heterogeneity index; E1: Pielou evenness index; and E2: Sheldon evenness index.