Humification and Humic Acid Composition of Suspended Soil in Oligotrophous Environments in South Vietnam

Table 3

Carbon species in humic acids of soils investigated.

Sample	Chemical shifts values (ppm) and related carbon species content
	190–170	170–150	150–135	135–108	108–100	100–70	70–50	50–32	32–27	27–10	10–0	Aromatic	Aliphatic
1	9.00	8.90	6.64	17.25	4.16	14.81	13.32	12.15	4.99	8.41	0.38	0.36	0.64
2	9.01	8.01	6.15	15.22	4.33	15.33	15.35	12.17	5.06	8.99	0.39	0.33	0.67
3	8.33	8.60	6.68	16.30	4.16	15.23	14.94	12.29	5.00	8.17	0.31	0.34	0.66
Average	8.78	8.50	6.49	16.25	4.21	15.12	14.54	12.20	5.01	8.52	0.36	0.34	0.66