摘要

    在堆肥过程中，添加生物炭（BC）和泥炭（PT）期间，抗生素抗性基因（ARGs）谱的主要贡献者尚未得到充分研究。这项研究调查了BC和PT修正对ARGs命运，污水污泥堆肥中细菌群落和重金属的影响。与对照相比，堆肥后，BC和PT降低了ARG的总丰度，分别降低了17.6％和43.0％。放线菌，拟杆菌，硬毛菌和变形杆菌是堆肥过程中的主要门，其中，硬毛菌（主要是杆菌科）是多种ARGs的潜在宿主。 BC和PT的添加降低了细菌病原体（如拟杆菌和假单胞菌）的丰度。此外，在第40天，BC和PT处理的铜（Cu），锌（Zn）和铅（Pb）的浓度均低于对照，并且这些金属与sul1和intI1呈显着正相关。此外，变异分区分析（VPA）显示，细菌群落对ARG模式的贡献最大，高达34.0％，其次是重金属（10.8％）和intI1基因（1.5％）。这些结果表明，生物炭和泥炭可通过锐化细菌组成来降低污水污泥中ARG的风险。

    The main contributors to antibiotic resistance genes (ARGs) profiles during the composting process under the addition of biochar (BC) and peat (PT) were not fully explored. This study investigated the influence of BC and PT amendment on ARGs fate, the bacterial community and heavy metals in sewage sludge compost. Compared to control, BC and PT declined the total abundances of ARGs by 17.6% and 43.0% after composting. Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria were the dominant phyla across the composting process, among which, members of Firmicutes (mainly Bacillaceae) were the potential hosts for multiple ARGs. BC and PT addition declined the abundance of bacterial pathogens such as Bacteroides and Pseudomonas. Besides, the concentrations of copper (Cu), zinc (Zn) and lead (Pb) were less in BC and PT treatments than control on day 40, and these metals displayed significant positive correlations to sul1 and intI1. Furthermore, variation partitioning analysis (VPA) revealed that the bacterial community exhibited the most contribution to the ARG patterns, as much as 34.0%, followed by heavy metals (10.8%) and intI1 gene (1.5%). These results suggested that biochar and peat can reduce the risks of ARGs in sewage sludge mainly by sharping the bacterial composition.

    https://www.sciencedirect.com/science/article/pii/S0147651321003018