Studies of semiquinone free radicals by ESR in the whole soil, HA, FA and humin substances

in this work it was studied soil organic matter from a gley soil, using esr (electron spin resonance spectroscopy). the studied soil samples were collected in rio de janeiro, brazil. humic and fulvic acid, humin macromolecules, and whole soil samples were analyzed. the results showed that the amount and line width of semiquinone free radical from whole soil samples had good correlation with humin fraction and no correlation with humic and fulvic acids contents.