Nitrification definition

How important is chemical nitrification in soils Although present evidence indicates that chemical oxidation of ammonia in soils occurs to only a minor extent, if at all, recent researches have definitely established that chemical oxidation of nitrites can and does occur more rapidly than biological oxidation wherever nitrites are present in very acid soils. It follows then that the importance of chemical nitrification is dependent primarily on the extent to which nitrites or nitrous acid are formed in, o r move into, soils of pH values where chemical oxidation can occur. As stated above, this critical pH value is near 5 to 5.2, or a little lower for very rapid oxidation. 

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