Functional trait and community phylogenetic analyses reveal environmental filtering as the major determinant of assembly of tropical forest tree communities in the Western Ghats biodiversity hotspot in India

Forest Ecosystems

Table 4 The results of the t-tests between functional trait metrics (Range and Variance) and forest types

Variable	Comparison	Mean	T	P value	Clustered (%)	Overdispersed (%)
Leaf size (Range)
Forest type	EVG/MD	1.364	2.740	0.007	4	66
	MD/DD	0.692	4.890	0.0001	0	35
	DD/EVG	−0.650	7.881	0.0001	40	0
Leaf size (Variance)
Forest type	EVG/MD	1.162	3.132	0.002	2	57
	MD/DD	0.606	4.0382	0.0003	0	30
	DD/EVG	−0.960	8.042	0.0001	35	0
Wood density (Range)
Forest type	EVG/MD	−1.14	1.343	0.183	57	0
	MD/DD	−0.794	2.214	0.0329	45	5
	DD/EVG	−1.583	1.878	0.064	75	0
Wood density (Variance)
Forest type	EVG/MD	−0.839	1.236	0.219	41	0
	MD/DD	−0.483	2.201	0.0339	40	0
	DD/EVG	−1.245	1.558	0.124	60	0
Seed size (Range)
Forest type	EVG/MD	−0.809	1.635	0.125	45	7
	MD/DD	−0.301	3.976	0.0003	25	10
	DD/EVG	0.839	6.242	0.0001	50	10
Seed size (Variance)
Forest type	EVG/MD	0.0280	−0.156	0.876	12.5	11
	MD/DD	−0.006	2.924	0.006	15	10
	DD/EVG	0.796	3.510	0.0008	5	45

Percentage values represent the proportion of sites that were significantly clustered and overdispersed assemblages per category. Bold numbers represent the statistically significant results. EVG evergreen; DEC deciduous; MD moist deciduous; DD dry deciduous. The formula for t-test used is \( t=\left(\overline{x_1}-\overline{x_2}\right)/\sqrt{\left(\left({N}_1-1\right){s_1}^2+\left({N}_2-1\right){s_2}^2/{N}_1+{N}_2-2\right)\left(1/{N}_1+1/{N}_2\right)} \), where x̅₁ and x̅₂ represent means of two different forest types; N₁ and N₂ are sample size and s₁² and s₂² are an estimator of the common variance of the two samples
Significant results are indicated in bold