Humification of organic waste material during earthworm composting

Eight mixtures of organic waste material were submitted to a sanitizing phase and then a composting phase promted by earthworms (Eisenia foetida). At the end of the first phase the decomposition of organic matter and lignin, the total humic carbon and its biological activity appeared stimulated in respect to the same parametres obtained at the end of the decomposting phase. Earthworms did not affect the humification process which appeared mainly influenced by the decomposition of the starting material.