The influence of humus fractionation on the chemical composition of soil organic matter studied by solid‐state 13 C NMR

SUMMARY Four samples of soil organic matter and their humic acids, fulvic acids and humin were studied with solid‐state 13 CP MAS NMR. The whole soil samples were fractionated using NaOH and HCl in order to extract humic acids, fulvic acids and humin. This investigation indicates that conventional humus fractionation does not significantly change the content of different functional groups in soil.