Microbial Ecology Mechanism For Quick Degradation Of Sulfamethoxazole During Chicken Feces Composting

As the additive,sulfonamides(SAs) were increasingly used in livestock and poultry industry. Feces containing SAs residues used as organic fertilizer may have potential hazards to agricultural ecological environments. In the present thesis, to solve the SAs residues problem in feces, sulfamethoxazole(SMZ)was chosen as target antibiotic for the elimination study in chicken feces compost and a high performance liquid chromatography(HPLC) method was established and applied for the determination of SMZ residues. Meanwhile, the degradation of SMZ along with time, TP ? TK and other elements and microorganism diversity were investigated during chicken feces composting using the method of aerobic-composting. The main results were as follow:(1)The removal rate of SMZ in chicken feces decreased with the increasing of SMZ concentrations in chicken feces. SMZ could decrease the ascent rate of composting temperature and make thehigh temperature(?50oC) period shorter than that of the control.The maturity of chicken feces composting decreased significantly when the SMZ addition contents were higher than 75 mg kg-1,which was proven from that the germination index(GI) of the treatments were much lower than 80%.(2)The study about effects of different exogenous microbial(T4 bacteria or FZC3 fungi) agents on SMZ(100 mg·kg-1)degradation in compost of chicken manure shows that the added microorganism increased the rising rate of composting temperature and make the high temperature(?50?) period longer than that of the control. The composting products of treatments adding T4 bacteria or FZC3 fungi have already reached to the standard of mature at the time of 28 days, which was proven from that the GI was higher then 91%. Compared with the control,addition of T4 and FZC3 increased the total phosphorus and potassium contents in chicken feces composting about 38.08% ~54.68%and 70.29% ~ 88.74%, respectively.(3) High-throughput sequencing results showed that:High-throughput sequencing method was adopted to study the bacterial and fangus diversity in the process of fresh chicken feces high-temperature aerobic-composting. The results show that the addition of SMZ could suppress the species richness andinhibit the growth of normal microflora. Thereinto, the Sordariomycetes was susceptible to SMZ. And as the compostion progressed, significant variation of bacterial and fungal microflora occurred. The main bacteria were Firmicutes and Proteobacteria at high temperature composting period, and the main fungi were Ascomycota and Basidiomycota.