Estimation of Copper and Cadmium Bioavailability in Contaminated Soil Remediated by Different Plants and Micron Hydroxyapatite

Table 2

Surface soil properties after the harvest of four plant species during the three years.

Time	Treatment	pH	SOC; g kg^−1	T-N; g kg^−1	A-N; mg kg^−1	T-P; g kg^−1	A-P; mg kg^−1	T-K; g kg^−1	A-K; mg kg^−1	CEC; cmol kg^−1
2013	CK	4.24 ± 0.207b	16.2 ± 0.191a	1.11 ± 0.0379a	52.5 ± 7.85a	0.190 ± 0.0100b	86.9 ± 1.71c	2.06 ± 0.140a	51.6 ± 2.98b	8.32 ± 0.0153a
	MW	5.17 ± 0.118a	16.3 ± 0.0458a	1.36 ± 0.0666a	54.8 ± 4.31a	0.620 ± 0.0872a	120 ± 7.26b	2.25 ± 0.0800a	94.3 ± 6.97a	8.41 ± 0.149a
	ME	5.33 ± 0.0503a	17.8 ± 0.398a	1.32 ± 0.0900a	55.8 ± 12.6a	0.650 ± 0.0306a	170 ± 9.12a	2.14 ± 0.164a	82.4 ± 15.1ab	8.63 ± 1.15a
	MS	5.19 ± 0.102a	18.0 ± 0.508a	1.26 ± 0.104a	52.6 ± 1.16a	0.780 ± 0.0723a	152 ± 5.89a	2.32 ± 0.0851a	94.7 ± 12.6a	7.84 ± 0.974a
	MP	5.15 ± 0.135a	18.0 ± 1.39a	1.27 ± 0.173a	52.5 ± 3.01a	0.710 ± 0.202a	149 ± 15.8a	2.07 ± 0.135a	71.7 ± 20.4ab	8.65 ± 0.575a
2014	CK	4.23 ± 0.110b	16.1 ± 0.172 b	1.05 ± 0.0306a	52.8 ± 7.06a	0.190 ± 0.0379b	88.1 ± 15.3b	1.97 ± 0.121b	49.5 ± 3.28b	8.39 ± 0.0404a
	MW	5.16 ± 0.130a	16.2 ± 0.118b	1.40 ± 0.0305a	56.3 ± 1.79a	0.620 ± 0.0764b	120 ± 10.2a	2.33 ± 0.0839a	98.0 ± 5.66a	8.53 ± 0.285a
	ME	5.24 ± 0.261a	18.4 ± 0.725a	1.33 ± 0.112a	56.4 ± 14.1a	0.520 ± 0.0404a	134 ± 3.60a	2.16 ± 0.159ab	84.0 ± 15.0ab	8.64 ± 0.710a
	MS	5.13 ± 0.195a	18.4 ± 0.239a	1.25 ± 0.123a	53.0 ± 0.197a	0.680 ± 0.0608a	132 ± 4.90a	2.31 ± 0.114ab	95.6 ± 13.4a	8.47 ± 0.180a
	MP	5.14 ± 0.253a	18.8 ± 0.546a	1.27 ± 0.251a	52.2 ± 2.47a	0.630 ± 0.242a	128 ± 3.27a	2.07 ± 0.147ab	72.0 ± 20.5ab	8.56 ± 0.206a
2015	CK	4.20 ± 0.280b	16.5 ± 0.451b	1.08 ± 0.0600b	54.0 ± 7.00a	0.190 ± 0.0153b	89.4 ± 4.02b	2.02 ± 0.0945c	51.1 ± 3.57b	8.36 ± 0.140b
	MW	5.03 ± 0.137a	16.6 ± 0.358b	1.45 ± 0.0379a	58.9 ± 3.70a	0.510 ± 0.136a	98.0 ± 5.70ab	2.43 ± 0.0265a	103 ± 5.12a	8.51 ± 0.0929b
	ME	5.26 ± 0.172a	19.0 ± 0.593a	1.46 ± 0.0436a	61.7 ± 11.9a	0.460 ± 0.0252ab	118 ± 5.16a	2.38 ± 0.0802ab	92.5 ± 12.9a	8.84 ± 0.071a
	MS	5.13 ± 0.161a	18.6 ± 1.09a	1.28 ± 0.0751ab	54.1 ± 2.05a	0.620 ± 0.102a	119 ± 11.5a	2.39 ± 0.0322ab	99.3 ± 16.8a	8.53 ± 0.0200b
	MP	5.07 ± 0.0971a	19.5 ± 0.478a	1.35 ± 0.276ab	55.5 ± 2.00a	0.550 ± 0.140a	116 ± 14.2a	2.20 ± 0.128bc	76.5 ± 19.1ab	8.56 ± 0.0819b

CK = untreated soil, MW = hydroxyapatite + Setaria lutescens, ME = hydroxyapatite + Elsholtzia splendens, MS = hydroxyapatite + Sedum plumbizincicola, MP = hydroxyapatite + Pennisetum sp. SOC, soil organic carbon; T-N, total nitrogen; T-P, total phosphorus; T-K, total potassium; A-N, available nitrogen; A-P, available phosphorus; A-K, available potassium; and CEC, cation exchange capacity. Different lowercase letters indicate significant differences between treatments at the same time (n = 3, ).