Protein binding phenolics and the inhibition of nitrification in subalpine balsam fir soils

Abstract

Nitrification in a highly active Al horizon of a balsam fir forest floor soil can be greatly inhibited by an aqueous methanol extract of the forest floor. This extract was fractionated in an attempt to identify the compounds responsible for the inhibition. Condensed tannins, smaller molecular weight phenolics, and their distribution on particulate matter in the extract were the most important inhibiting components of the extract. When all phenolic material was removed from the extract, the remaining solution stimulated nitrification.