Fulvic acid

Fulvic acids, as well as humic acids, are a family of organic acids, natural compounds, components of the humus, which is a fraction of soil organic matter. The differences between these two are the carbon and oxygen contents, acidity, degree of polymerization, molecular weight, and colour. Fulvic acids remain in solution after removal of humic acid from humin by acidification.

Fulvic acid is of relatively low molecular mass and is biologically more active than humic acid.

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