The effect of drying on the colloidal properties and stability of humic compounds

It is indicated here that organic macro molecules in the soil are aggregated due to bonds, presumably hydrogen bonds, formed in the presence of water. When the soil is dried, this structure is broken and the stability of the organic matter decreases. This process is not an instantaneous process and apparently some relaxation period is needed for a complete dispersion of the organic matrix. An appreciable fraction of the organic molecules is hindered, even from contact with the solution in the aggregated structure, as indicated by the lower acidity in the wet soil. This steric hinderence seems to be one of the important factors contributing to the stability of humic compounds.