Production of Amino Acids and Its Effect on the Formation of Humic Acids during Composting

The dynamic of amino acids (AA) concentration and the influence on the formation of humic acids (HAs) were investigated during composting of cabbage waste (CW), lawn waste (LW), chicken manure (CM), garden waste (GW) and corn straw (CS). The results showed that AAs concentration was decreased during composting process. The decrease in LW (90.7%) and CS (80.9%) was more than CM (67.4%), GW(51.3%) and CW(50.1%). During the composting process, the HAs concentration was gradually increased. The increment of HAs concentration in LW (66.8%) was higher than CW (38.9%), CS(43.9%) and CM(33.6%), while GW was only 4.6%. The significantly inverse correlations have been obtained between AA and HAs concentration during LW, CW and CS composting, suggesting that AA derived from the cellulose materials composting can observably promote the formation of HAs.