C. Mondini et al., CHANGES DURING PROCESSING IN THE ORGANIC-MATTER OF COMPOSTED AND AIR-DRIED POULTRY MANURE, Bioresource technology, 55(3), 1996, pp. 243-249
Citations number
14
Categorie Soggetti
Energy & Fuels","Biothechnology & Applied Migrobiology",Agriculture
Composting and active drying are the main techniques employed to preve
nt losses of NH3 and development of undesirable odours from poultry ma
nure. We studied the effects of these treatments on C and N content an
d stabilization of organic matter Carbon and N contents of composted p
oultry manure (CPM) at the end of the processes were 82.9 and 56.1%, r
espectively, bf the initial material, whereas the C content of dried p
oultry manure (DPM) remained practically the same, while the N content
slightly increased with time. Nitrogen content of DPM at the end of t
he process was about three times higher than that of CPM (55.1 and 19.
2 mg/g, respectively). The humification index (HI) showed a decreasing
trend in both products, indicating the formation of humic substances
in both processes, although to different extents: even at 20 days CPM
showed HI values typical of a well-matured material (0.50), whereas HI
for DPM at the end of the process was 1.14, indicating that this mate
rial did not achieve stabilization. Application of electrofocusing (EF
) to characterize the qualitative evolution of humic substances showed
a more complex EF profile in the case of CPM and confirmed the higher
stabilization of OM in the composted material. CPM could be useful as
a soil amendment because of its high degree of stabilization, whereas
DPM can be considered mainly as an organic fertilizer; because of its
high content of N. If DPM was piled for a long period its OM could ac
hieve a high degree of humification, so increasing the agronomic quali
ty of this fertilizer. (C) 1996 Elsevier Science Ltd.