Organic matter and nitrogen distribution, and functional groups of filter at earthworm packing bed in vermifiltration

This paper studies organic matter (OM) and nitrogen (N) distributions at different depths of an earthworm packing bed, and the N distribution in situ solution in artificial soil (AS). The contents of OM, nitrate nitrogen (NO₃-N), ammonia nitrogen (NH₃-N), and total nitrogen (TN) changed along with the depth of AS. The results of N concentration in situ solution indicated that 35 cm to 40 cm thickness of earthworm packing bed thickness was optimal for removing NH₃-N and TN for synthetic wastewater treatment. Fourier transform infrared spectra showed that most intensity variations of the absorbance peaks increased in AS, decreased in detritus, and slightly changed in sand after synthetic wastewater treatment. Furthermore, certain functional chemical attributes might evaluate the OM contents at the VF media, and AS could act as the main matrices for OM reaction.