Phytoremediation of Gold Mine Tailings Amended with Iron-Coated and Uncoated Rice Husk Ash by Vetiver Grass (Vetiveria zizanioides (Linn.) Nash)

Table 5

Biological accumulation coefficient (BAC), biological transfer coefficient (BTC), and bioconcentration factor (BCF) of heavy metals by vetiver grass grown in the gold mine tailings amended with Fe-RHA and RHA (mean ). Different letters correspond to significant differences between rates of the same ash ( < 0.05) in the same column.

	Type	Rate (%)	As	Cd	Cr	Cu	Mn	Zn
BAC	Control	0	0.009	0.011	0.315	0.493	0.174	0.858
	RHA	5	0.010	0.015	0.375	0.640	0.148	0.533
	RHA	10	0.020	0.017	0.343	0.422	0.129	0.436
	RHA	20	0.025	0.016	0.369	0.542	0.137	0.393
	Control	0	0.009	0.009	0.257	0.619	0.200	0.816
	Fe-RHA	5	0.006	0.011	0.643	0.603	0.166	0.567
	Fe-RHA	10	0.011	0.015	0.314	0.564	0.134	0.739
	Fe-RHA	20	0.011	0.011	0.256	0.610	0.118	0.365
BTC	Control	0	0.321	0.211	3.089	1.554	2.802	1.119
	RHA	5	0.198	2.000	7.821	2.389	3.355	0.449
	RHA	10	0.411	0.532	2.054	2.215	1.283	0.334
	RHA	20	0.104	0.351	2.394	2.031	1.925	0.356
	Control	0	0.329	0.201	2.153	1.631	2.782	0.981
	Fe-RHA	5	0.104	0.357	5.350	2.031	2.957	0.314
	Fe-RHA	10	0.127	0.273	2.183	2.497	2.193	0.715
	Fe-RHA	20	0.075	0.112	2.927	1.867	1.857	0.363
BCF	Control	0	0.027	0.051	0.102	0.318	0.062	0.770
	RHA	5	0.051	0.008	0.049	0.267	0.044	1.192
	RHA	10	0.050	0.032	0.167	0.191	0.100	1.307
	RHA	20	0.243	0.044	0.155	0.267	0.071	1.108
	Control	0	0.027	0.045	0.119	0.380	0.072	0.832
	Fe-RHA	5	0.062	0.032	0.120	0.296	0.056	1.806
	Fe-RHA	10	0.084	0.056	0.145	0.229	0.061	1.035
	Fe-RHA	20	0.145	0.101	0.088	0.327	0.064	1.005