Table 4.

Mantel test of the relationship of whole microbial community functional structure to individual environmental variables

Environmental variable	rM	P
pH	0.1835	0.124
ORP	0.1654	0.113
S	0.6039	0.008
Cu	0.9374	0.001
Pb	0.6547	0.012
Zn	0.7414	0.016
As	0.3163	0.026
Cd	0.7656	0.005
Ni	0.2332	0.039
Hg	0.8819	0.001
Cr	0.7437	0.003

Boldface values indicate significant P values (<0.01)