摘要
      河流网络在抗生素抗性基因（ARGs）的传播中发挥着重要作用。ARGs在河网中的发生、多样性和丰度已被广泛调查。然而，在空间和时间上形成ARG轮廓的组装过程在很大程度上是未知的。在这里，通过高通量定量PCR和多重统计分析揭示了河网（太湖流域）ARGs剖面的动态，以评估潜在的生态过程。结果显示，ARGs剖面在潮湿、正常和干燥季节有明显的变化。同时，ARGs剖面的相似性与地理距离之间存在显著的负相关（p<0.01），表明ARGs剖面呈现距离衰减模式。零模型分析表明，ARGs剖面主要是通过确定性过程组装的。冗余分析和分层划分表明，环境属性（主要是pH和温度）是影响ARGs剖面动态的主要因素。总之，这些结果表明，环境过滤是形成ARGs剖面的主要生态过程。这项研究增强了我们对抗生素耐药性是如何在河网中聚集的理解，并将有利于制定控制ARGs传播的管理策略。
Abstract
River networks play important roles in dissemination of antibiotic resistance genes (ARGs). The occurrence, diversity, and abundance of ARGs in river networks have been widely investigated. However, the assembly processes that shaped ARGs profiles across space and time are largely unknown. Here, the dynamics of ARGs profiles in river networks (Taihu Basin) were revealed by high-throughput quantitative PCR followed by multiple statistical analyses to assess the underlying ecological processes. The results revealed clear variations for ARGs profiles across wet, normal, and dry seasons. Meanwhile, a significant negative correlation (p < 0.01) was observed between the similarity of ARGs profiles and geographic distance, indicating ARGs profiles exhibited distance-decay patterns. Null model analysis showed that ARGs profiles were mainly assembled via deterministic processes. Redundancy analysis followed by hierarchical partitioning revealed that environmental attributes (mainly pH and temperature) were the major factors affecting the dynamics of ARGs profiles. Together, these results indicated that environmental filtering was the dominant ecological process that shaped ARGs profiles. This study enhances our understanding how the antibiotic resistome is assembled in river networks and will be beneficial for the development of management strategies to control ARGs dissemination.

https://www.sciencedirect.com/science/article/abs/pii/S0048969722023865