Nguyễn Xuân Cự*
*Bộ môn Thổ nhưỡng – Trường Đại học KHTN, ĐHQG Hà Nội
Từ khoá: thành phần, tính chất, chất hữu cơ, đất, Việt Nam
The composition and typical properties of organic matter of some soil types in Vietnam
The soils were classified as eutric fluvisols, distric fluvisols, thionic fluvisols, arenosols, haplic acrisols and ferralic acrisols. Various organic fractions were separated using chemical methods. The results showed that total contents of organic carbon in soils are low usually ranged between 10-20gC/kg soil. Humus substances are the main components of the soil organic matter. Among them, contents of fulvic acid are usually higher than the humic acid. That lead to low ratios of humic and fulvic acid ranging about 0.57-0.95. organic matter has high mobility due to the fractions of free humic and fulvic acids are dominant. Because of contributing the main role of cation exchange capacity, the content of soil organic matter is highly and positive correlation with the cation exchange capacity of soil.