摘要

       污水污泥通常被认为是抗生素抗性基因 (ARG) 的重要储存库，可在堆肥后作为肥料进入农业系统。土壤类型和污泥堆肥的差异可能影响了土地施用污泥堆肥后抗生素抗性细菌 (ARB) 的命运，这一点值得澄清。因此，研究了将三种类型的污泥堆肥（A、B 和 C）应用于三种不同土壤（红土、黄土和黑土）后，ARB 和 ARG 的去向。结果表明，在堆肥过程中富集最多的 tetX 不影响土壤抗性，而 tetG 则有影响。土壤类型显着影响 ARB 和 ARGs 的动态，而堆肥类型之间没有观察到显着差异。在堆肥 B 的堆肥过程中减少 ARGs 的优势并没有扩展到土地应用。早期堆肥的土地施用对微生物群落影响显着，但微生物群落逐渐恢复到控制模式。与其他因素（包括重金属共同选择、水平基因转移、生物量和环境因素）相比，微生物群落的变化对红土和黑土中 ARGs 的动态贡献更大，而由 intI1 水平反映的水平基因转移对 ARGs 的动态贡献更大。黄土中最多。

       Sewage sludge was generally considered a significant reservoir of antibiotic resistance genes (ARGs) and could enter agricultural systems as fertilizer after composting. Soil types and the discrepancy of sludge composts could have influenced the fate of antibiotic-resistant bacteria (ARB) following the land application of sludge composts, which deserved to be clarified. Thus, the fate of ARB and ARGs following the land application of three types of sludge composts (A, B, and C) to three different soils (red soil, loess, and black soil) was investigated. The results showed that tetX, which was enriched the most during composting, did not affect the soil resistome, whereas tetG did. Soil types influenced the dynamics of ARB and ARGs significantly, whereas no significant difference was observed among compost types. The advantage of reducing ARGs during the composting process in compost B did not extend to land application. Land application of composts influenced the microbial community significantly at the early stage, but the microbial community returned to the control pattern gradually. Changes in the microbial community contributed more to the dynamics of ARGs in red and black soil compared with other factors, including co-selection from heavy metals, horizontal gene transfer, biomass and environmental factors, whereas horizontal gene transfer, reflected by intI1 levels, contributed the most in loess.

https://www.sciencedirect.com/science/article/pii/S0160412017322857