Origins of humus variation

Humus samples derived from peat, moss or ornithogenic sources in the Antarctic continent have been examined by 13 C nuclear magnetic resonance techniques. The 13 C spectra show that the humus has undergone very little chemical modification. A fulvic acid fraction from a moss derived soil is almost entirely α- and β-glucose. The results also show that lignin is not a necessary precursor for aromatic components in soils. It is suggested that the aromaticity and carbohydrate content of certain soils is governed by the low temperature which influences the degree of humification.