FORMATION OF HUMIC SUBSTANCES DURING COMPOSTING WHEAT STRAW

During composting straw (with and without N-addition) in a model-compostreactor with continuous progress of rotting it comes to an increase of the fraction of humic acids under simultaneousness decrease of their prestages. The synthesis of humic acids is strongly marked in the thermophilic area. Compared with the untreated variant up to 30% more of the humic acids are formed in the N-treated plots. After the maximum temperature the formation of humic acids break down. A direct relation exists between the microbiological decomposition of the organic matter and the formation of humic acids. IR-spectroscopic measurements show no qualitative differences either between or within the compost variants.