EFFECT OF LIGNITE HUMIC-ACID TREATMENT ON THE RATE OF DECOMPOSITION OF WHEAT-STRAW

Comparisons were made between the rates of microbial respiration during the incubation of milled wheat straw in the presence or absence of a dispersal of lignite humic acids. Lignite treatment significantly reduced both the rate of O-2 consumption and CO2 evolution from the straw substrate over a 4-week period. In view of this observed inhibitory effect, additions of exogenous humic acids from lignite during composting might have a practical application as a means of increasing the microbial stability of horticultural composts derived from plant waste materials.