Chemical forms of phosphorous and physicochemical properties of acid soils of Cheha and Dinsho districts, southern highlands of Ethiopia

Environmental Systems Research

Table 7 Oxalate and dithionite citrate bicarbonate extractable Al, Fe and P

Sites	Al_ox	Fe_ox	P_ox	PSC	P ^a_ox	Al_d	Fe_d	Al_d-Al_ox	Fe_ox/Fe_d	Scaling factor (α)
Sites	(mmol kg⁻¹)				DPS (%)		(mmol kg⁻¹)		Fe_ox/Fe_d	Scaling factor (α)
SC1	152.37	97.70	5.51	133.54	4.13	173.33	633.66	20.6	0.24	0.62
SC2	139.07	78.54	6.17	116.20	5.31	151.85	478.04	12.78	0.29	0.62
SC3	145.96	88.18	5.82	125.03	4.65	164.07	551.61	18.11	0.27	0.57
SC4	130.07	79.96	6.07	112.16	5.41	144.07	456.25	14.00	0.29	0.59
SC5	126.37	77.46	7.07	108.85	6.49	149.26	491.61	22.89	0.26	0.61
SC6	131.85	76.39	7.32	111.20	6.58	161.11	476.61	29.26	0.28	0.62
SC7	134.37	81.75	6.45	115.41	5.59	150.74	498.75	16.37	0.27	0.56
SD1	90.00	66.21	9.74	83.42	11.68	119.26	313.93	29.26	0.29	0.42
SD2	91.85	82.29	8.26	92.99	8.88	112.19	355.54	20.33	0.26	0.45
SD3	71.89	51.75	12.29	66.02	18.62	134.07	281.07	62.19	0.26	0.45
SD4	90.37	59.43	8.39	79.99	10.49	128.52	307.14	38.15	0.29	0.44
SD5	78.15	63.36	10.35	75.56	13.69	124.07	291.43	45.93	0.27	0.44
Mean	115.19	75.25	7.79	101.70	8.46	142.71	427.97	27.52	0.27	0.53

Al_ox oxalate extractable Al, Fe_ox oxalate extractable P_ox oxlate extractable P, PSC phosphorous sorption capacity, DPS P saturation with respect to Pox, Al_d dithionite extractable Al, Fe_d dithionite extractable Fe