摘要

    牲畜粪便是抗生素抗性基因（ARG）的储存库，好氧堆肥被广泛用于动物粪便的回收利用。这项研究调查了在猪粪堆肥过程中，添加0、100和1000 mg / kg的纳米零价铁（nZVI）对ARGs和移动遗传元素（MGEs）的命运。在100 mg / kg的nZVI下，堆肥后sul1，sul2，dfrA7，ermF和ermX的相对丰度降低了33.26-99.31％，而intI2和Tn916 / 1545的相对丰度分别降低了95.59％和97.65％。 。大多数ARG和MGE同时发生，并且它们之间具有很强的相关性。堆肥期将细菌群落结构显着分离，并且在同一阶段的不同处理下它们聚集在一起。网络分析表明，Solibacillus，Clostridium_sensu_stricto_1，Terrisporobacter，Romboutsia，Turicibacter，Lactobacillus，Planococcus，Dietzia和Corynebacterium_1是ARGs和MGEs的常见潜在宿主。冗余分析表明，MGEs对ARGs相对丰度的变化具有关键影响。添加100 mg / kg nZVI可以通过降低MGE的含量来降低ARGs的环境风险。

    Livestock manure is a reservoir for antibiotic resistance genes (ARGs), and aerobic composting is used widely for recycling animal manure. This study investigated the effects of adding nano-zerovalent iron (nZVI) at 0, 100, and 1000 mg/kg on the fates of ARGs and mobile genetic elements (MGEs) during swine manure composting. Under nZVI at 100 mg/kg, the relative abundances of sul1, sul2, dfrA7, ermF, and ermX decreased by 33.26–99.31% after composting, and the relative abundances of intI2 and Tn916/1545 decreased by 95.59% and 97.65%, respectively. Most of the ARGs and MGEs co-occurred and they had strong correlations with each other. The bacterial community structure was significantly separated by the composting periods, and they clustered together under different treatments in the same phase. Network analysis showed that Solibacillus, Clostridium_sensu_stricto_1, Terrisporobacter, Romboutsia, Turicibacter, Lactobacillus, Planococcus, Dietzia, and Corynebacterium_1 were common potential hosts of ARGs and MGEs. Redundancy analysis suggested that MGEs had key effects on the variations in the relative abundances of ARGs. Adding 100 mg/kg nZVI could reduce the environmental risk of ARGs by decreasing the abundances of MGEs.

    https://www.sciencedirect.com/science/article/abs/pii/S0269749119336474