摘要

       堆肥广泛用于动物粪便处理，竹炭（BC）可用于堆肥过程中的氮保护。然而，BC对鸡粪堆肥过程中抗生素抗性基因（ARGs）的影响仍不清楚。本研究调查了在鸡粪堆肥中添加不同比例的 BC（0%、5%、10% 和 20% w/w）对 ARG 的影响。 26 天后，大多数 ARG（tetC、tetG、tetW、tetX、sul2、drfA1、drfA7、ermB、ermF、ermQ 和 ermX）和 intI1 的相对丰度（RA）下降了 21.6-99.5%，而 sul1 增加了7.5-17.7 倍。 0%、5%、10% 和 20% BC 的平均 RA 减少分别为 0.85、1.05、1.08 和 1.15 个对数。根据冗余分析，ARG 剖面最重要的环境因素是温度。此外，BC显着降低了生物铜和生物锌的水平，从而降低了重金属的共选择压力。不同比例的BC对tetG、tetW、tetX、sul2、drfA1和ermB的去除没有显着影响。与其他处理相比，补充 10% BC 在去除 tetC 和 drfA7 方面更有效。结果表明，添加 10% BC 适合减少鸡粪堆肥中的 ARG。

       Composting is widely used for animal waste disposal, and bamboo charcoal (BC) can be used for nitrogen conservation during composting. However, the effects of BC on antibiotic resistance genes (ARGs) during chicken manure composting are still unclear. This study investigated the effects on ARGs of adding different proportions of BC (0%, 5%, 10%, and 20% w/w) to chicken manure compost. After 26 days, the relative abundances (RAs) of most ARGs (tetC, tetG, tetW, tetX, sul2, drfA1, drfA7, ermB, ermF, ermQ, and ermX) and intI1 declined by 21.6–99.5%, whereas sul1 increased by 7.5–17.7 times. The average RAs reductions with 0%, 5%, 10%, and 20% BC were 0.85, 1.05, 1.08, and 1.15 logs, respectively. The most important environmental factor for the ARG profiles was temperature according to redundancy analysis. Furthermore, BC significantly decreased the bio-Cu and bio-Zn levels, thereby reducing the co-selection pressure from heavy metals. Different proportions of BC had no significant effects on the removal of tetG, tetW, tetX, sul2, drfA1, and ermB. Supplementation with 10% BC was more effective at removing tetC and drfA7 compared with the other treatments. The results suggested that 10% BC supplementation is appropriate for reducing ARGs in chicken manure compost.

https://www.sciencedirect.com/science/article/abs/pii/S014765131730009X