The Interactions among the Heavy Metals in Soils and in Weeds and Their Antioxidant Capacity under the Mining Activities in Thai Nguyen Province, Vietnam

Table 3

The correlation coefficient of 5 environmental factors on the HMs in plant tissues, roots, shoots, and leaves was calculated by envfit function in vegan R-package.

	All tissue n = 75		Root n = 25		Shoot n = 25		Leave n = 25
	r2		r2		r2		r2
Cu	0.40		0.65		0.55		0.59
Zn	0.42		0.57		0.59		0.71
As	0.18	0.002	0.03	0.72	0.37	0.008	0.34	0.009
Cd	0.30		0.39	0.007	0.44	0.005	0.35	0.009
Pb	0.10	0.036	0.13	0.24	0.45	0.003	0.12	0.244