Humus formation Process
Plant residues contain mainly lignin, carbohydrates, and protein. All of which are very high molecular weight, large size compound,s and are also chemically bound to one another. Microorganisms produce an extracellular enzyme that breaks down this macromolecule into smaller units. The Microorganisms are as who, a part of it is oxidized to CO2 and the rest is exuded in the form of different waste products (phenols/quinines) through the transformation. Polyphenols of the quinines appear to be common molecular waste that finds little use as a portion of food (energy) sources by Microorganisms. Such compound, therefore, accumulating soil. Phenol polymerization takes place under the influence of certain enzymes (phenol exuded) by Microorganisms. Phenols may also complement nitrogenous compounds (amino acids), sugar, and other degradation products in soil. As polymerization proceeds, the compound becomes dark brown or black and gets precipitated and humming polymers of various sizes are formed.
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