Effect of contamination sources on the rate of zinc, copper and nickel release from various soil ecosystems

Bulletin of the National Research Centre

Table 9 Cation exchange capacity CEC and exchangeable cations in selected soil samples (meq/100 g)

Soil	Dominant cations (EDC)				Pollutant cations (EPC)									∑EDC	∑EPC	CEC*
Soil	Na	K	Ca	Mg	Cd	Pb	Mn	As	Cr	Co	Zn	Ni	Cu	∑EDC	∑EPC	CEC*
Kombora
UC*	7.61	2.23	7.50	4.27	0.21	0.65	1.74	2.61	7.41	0.44	6.32	0.87	1.53	21.61	21.78	43.39
% exp	17.54	5.14	17.28	9.84	0.48	1.51	4.02	6.03	17.07	1.00	14.56	2.01	3.52
Sum%	49.80				50.20
C*	6.64	1.17	8.80	5.69	0.22	0.65	1.74	2.61	7.41	0.44	6.32	0.87	1.53	22.30	21.79	44.09
% exp	15.06	2.65	19.96	12.91	0.49	1.48	3.95	5.93	16.80	0.99	14.33	1.98	3.46
Sum%	50.60				49.40
Abo Rawash
UC*	3.35	0.56	5.61	3.56	0.07	0.29	0.69	1.33	1.21	0.18	0.41	0.34	0.40	13.08	4.92	18.00
% exp	18.62	3.11	31.19	19.79	0.40	1.60	3.82	7.37	6.73	0.98	2.29	1.89	2.21
Sum%	72.67				27.33
C*	2. 74	0.42	3.88	1.48	0.05	0.22	1.50	1.01	1.21	0.19	0.37	0.26	0.18	8.52	4.98	13.51
% exp	0.04	3.90	36.06	13.75	0.45	2.06	13.91	9.37	11.26	1.73	3.45	2.38	1.63
Sum%	63.10				36.90
Kafr-Elsheikh
UC*	14.60	1.58	3.11	4.16	0.14	0.45	5.76	4.14	3.71	0.56	1.08	1.11	0.30	23.45	17.25	40.70
% exp	35.87	3.88	7.64	10.22	0.34	1.12	14.16	10.17	9.11	1.37	2.66	2.72	0.73
Sum%	57.62				42.38
C*	13.81	1.47	3.22	3.35	0.12	0.32	5.14	0.65	4.26	0.62	0.83	0.94	0.31	21.85	13.19	35.04
% exp	39.45	4.20	9.20	9.57	0.35	0.92	14.68	1.86	12.18	1.78	2.36	2.68	0.88
Sum%	62.36				83.64

^*UC uncultivated soil, *C cultivated soil, *CEC calculated cation exchange capacity (meq/100 g), *EDC exchangeable dominant cations (meq/100 g), *EPC exchangeable polluted cations (meq/100 g)