Soil Organic Carbon Distribution in a Humid Tropical Plain of Cameroon: Interrelationships with Soil Properties

Table 5

Chemical properties and SOC stocks.

Horizon	Depth (cm)	pH-H2O	pH-CaCl2	pH-KCl	EC (dSm^−1)	SOC (%)	SOC stocks (t ha^−1)	SOC stocks at 100 cm depth (t ha^−1)	Al^3+ (cmolckg^−1)	H^+ (cmolckg^−1)
Profile 1. Bamia series
Ap	0–10	5.8	5.1	4.5	0.03	2.53	27.1		–	–
AB	10–24	5.6	4.8	4.2	0.01	2.53	41.1		–	–
Bw1	24–42	5.5	4.4	4.0	0.01	2.40	51.8		–	–
Bw2	42–72/90	5.4	4.4	4.0	0.01	2.50	128.7		0.9	0.0
Bw3	72/90–102	5.5	4.6	4.1	0.01	2.0	45.0	295.7	–	–
Cr1	102–157	5.6	4.5	4.1	0.01	2.0	111.1		–	–
Cr2	157–215	5.6	4.5	4.2	0.01	1.87	133.4		–	–
Profile 2. Santchou series
Ah	0–12	4.8	4.3	3.8	0.02	5.74	45.5		3.3	2.2
2Bt/E	12–38	4.8	4.5	4.1	0.01	3.91	114.9		1.8	2.3
2E/Bt	38–58	4.5	4.1	3.6	0.01	2.78	61.7		0.5	2.0
2Btg2	58–90	4.5	4.0	3.8	0.01	3.00	110.4		1.7	1.4
2Btg3	90–115	5.0	4.8	4.4	0.01	2.39	77.7	363.5	0.8	0.7
2C1	115–167	4.7	4.2	4.0	0.00	1.35	94.1		0.6	0.5
2C2	167–205	4.9	4.5	4.2	0.00	1.30	69.2		0.5	0.0
Profile 3. Lelem series
A	0–18	4.5	4.0	3.5	0.01	3.26	67.5		0.7	1.6
Bt1	18–43	4.7	4.1	3.6	0.01	3.35	99.7		0.5	1.5
Bt2	43–73	4.8	4.3	3.5	0.00	1.17	41.8		0.6	1.9
Btg	73–118/134	4.8	4.4	3.6	0.00	2.22	128.2	274.2	0.7	1.4
BCtg	118/134–175	4.9	4.3	3.8	0.01	1.57	87.7		0.4	1.3
Profile 4. Ntengie series
Ap	0–27	5.3	5.0	4.3	0.04	3.00	74.5		0.2	0.0
AB	27–50	5.2	4.7	4.3	0.02	3.65	65.5		0.2	0.0
Cg	50–82	5.2	4.8	4.3	0.02	2.48	88.1		0.2	0.0
2AB	82–116	5.4	5.0	4.8	0.02	2.22	60.4	260.1	0.3	0.0
2Btg	116–160	5.5	5.1	4.6	0.02	1.57	76.7		0.3	0.0
2BC	160–210	5.5	4.9	4.4	0.02	1.17	69.0		0.3	0.0
Profile 5. Bamengwi series
Ap	0–25	5.7	5.1	4.2	0.02	3.39	87.3		–	–
AB	25–44	6.0	5.6	4.6	0.01	2.61	50.1		–	–
BCt	41–66	6.0	5.3	4.5	0.01	2.22	72.2		–	–
2Cg1	66–102	6.2	5.8	4.7	0.01	1.30	60.8	264.0	–	–
3Cg2	102–134	6.1	5.6	4.9	0.01	2.09	87.6		–	–
4Cg3	134–162	6.4	5.8	5.1	0.01	2.11	78.0		–	–
5Cg4	162–205	6.2	5.8	4.9	0.01	1.08	59.9		–	–