摘要

    这项研究的目的是阐明在两年的负荷期间，三个污泥处理湿地（STW）中抗生素抗性基因（ARG）的分布及其清除机理。在装载期间建造并运行了三个STW单元：第1单元（U1）装有曝气管，第2单元（U2）装有曝气管和芦苇，而第3单元（U3）仅装有芦苇。在残留污泥中检测到所有靶向的ARGs，intI1和16S rRNA，其数量级为：16S rRNA> sul1> intI1> sul2> tetC> tetA> ermB。在加载期间，残留污泥中五个靶向的ARGs，intI1和16S rRNA的丰度增加，这可能是由于持续输入外源养分导致细菌增加所致。然而，STWs也可以在加载期间从污水中去除ARGs，五个抗性基因的平均去除效率为73.0％。 intI1和16S rRNA的去除率分别为73.5％和78.6％。在大多数ARGs和intI1以及16S rRNA的大量存在中检测到正相关（P <0.05），表明intI1在ARGs的传播中起着至关重要的作用。携带这些基因的细菌的去除也发生在STW单元中。

    The objectives of this study were to clarify the distribution as well as the removal mechanism of antibiotic resistance genes (ARGs) within three sludge treatment wetlands (STWs) during a loading period of two years. Three STW units were constructed and run during the loading period: Unit 1 (U1) built with aeration tubes, Unit 2 (U2) built with aeration tubes and reeds, and Unit 3 (U3) built with reeds only. All targeted ARGs, intI1, and 16S rRNA were detected in residual sludge in the order of magnitude: 16S rRNA>sul1>intI1>sul2>tetC>tetA>ermB. The abundance of the five targeted ARGs, intI1, and 16S rRNA increased in residual sludge, during the loading period, which may be due to the increase in bacteria caused by the continuous import of exogenous nutrients. However, STWs can also remove ARGs from sewage during the loading period and the mean removal efficiency of five resistance genes was 73.0%. The removal rates of intI1 and 16S rRNA were 73.5% and 78.6%, respectively. Positive correlations were detected in abundance of most ARGs and intI1, as well as 16S rRNA (P < 0.05), indicating intI1 plays a vital part in the propagation of ARGs. The removal of bacteria harboring these genes also occurs in the STW units.

   https://www.sciencedirect.com/science/article/pii/S0301479720311154