| Due to the development of the livestock industry, the usage of antibiotics gradually increased. However, most of the antibiotics were excreted through animal feces, which would threaten ecological environment and human health. Composting was an effective method to remove antibiotics. Therefore, we chose tetracycline as research object, which has a high detection rate and a large amount of residues in animal manure. We conducted a thermophilic aerobic compost experiment of pig manure and wheat straw, with 100 mg/kg tetracycline. Aimed to assess the effects on composting process, functional diversity of microbial communities, and degradation of tetracycline, we had mainly used Biolog and HPLC to complete this study. The main results are as follows:1. Tetracycline inhibited the rise of pile temperature; and tetracycline accelerated the fall of pile temperature in the cooling period. Adding tetracycline treatment(TC) had no significant influence on N, P, K and other nutrients indicators of the final compost product. Compared to CK, TC had more plant toxicity, but the final compost product also reached maturity.2. After 35 d composting, tetracycline has degraded 97.9%. The degradation curve of tetracycline followed a first-order kinetic pattern with a 2.58 d half-life. Thermophilic aerobic composting is an effective way to remove tetracycline.3. Tetracycline changed microbial community structure in composting process. In the megathermal period and the cooling period, tetracycline significantly inhibited microbial activity. However, in the maturity period, with the degradation of tetracycline and the formation of secondary metabolites, the microbial activity was promoted significantly. As to the utilization of six categories carbon source by microbial, the influence changed from inhibition of the premetaphase into promotion of the maturity period, in which especially significantly promoted the utilization on polyamines. |
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