The rapid expansion of human activity in a region can exacerbate human health risks induced by antibiotic resistance genes (ARGs). Peri-urban ecosystems serve at the symbiotic interface between urban and rural ecosystems, and investigations into the dissemination of ARGs in peri-urban areas provide a basic framework for tracking the spread of ARGs and potential mitigations. In this study, through the use of high-throughput quantitative PCR and 16S rRNA gene high-throughput sequencing, seasonal and geographical distributions of ARGs and their host bacterial communities were characterized in a peri-urban river. The abundance of ARGs in downstream was 5.2–33.9 times higher than upstream, which indicated distinct antibiotic resistance pollution in the areas where human lives. With the comparison classified based on land use nearby, the abundance of ARGs in samples near farmland and villages was higher than in the background (3.47–5.58 times), pointing to the high load in the river caused by farming and other human activities in the peri-urban areas. With the co-occurrence pattern revealed by network analysis, blaVEB and tetM were proposed to be indicators of ARGs which get together in the same module. Furthermore, seasonal variations in ARGs and the transport of bacterial communities were observed. The effects of seasonal temperature on the dissemination of ARGs along the watershed was also evaluated. The highest absolute abundance of ARGs occurred in summer (2.81 × 10⁹ copies/L on average), the trends of ARG abundances in four seasons were similar with local air temperature. The Linear discriminant analysis effect size (LEfSe) suggested that nine bacterial genera were implicated as biomarkers for the corresponding season. Mobile genetic elements (MGEs) showed significant positive correlation with ARGs (P < 0.01) and MGEs were also identified as the key-contributing factor driving ARG alteration. This study provides an overview of seasonal and geographical variations in ARGs distribution in a peri-urban river and draws attention to controlling pollutants in peri-urban ecosystems.

人类活动在该地区的迅速扩展会加剧由抗生素抗性基因（ARG）引发的人类健康风险。城郊生态系统是城乡生态系统之间的共生界面，对郊区边缘地区ARG传播的调查研究为追踪ARG的扩散和潜在缓解提供了基本框架。在这项研究中，通过使用高通量定量PCR和16S rRNA基因高通量测序，在城郊河流中对ARG及其宿主细菌群落的季节和地理分布进行了表征。下游的ARGs含量是上游的5.2–33.9倍，这表明在人类居住的地区存在明显的抗生素耐药性污染。根据附近的土地使用情况对比较进行了分类，农田和村庄附近样品中的ARGs含量高于背景值（3.47-5.58倍），表明郊区和周边地区的农业和其他人类活动在河流中造成了高负荷。通过网络分析揭示了共现模式，blaVEB和tetM被认为是在同一模块中聚集在一起的ARG的指标。此外，观察到了ARGs的季节性变化和细菌群落的运输。还评估了季节性温度对沿流域的ARG传播的影响。夏季ARG的绝对丰度最高（ 平均为2.81×10 ⁹拷贝/ L），四个季节的ARG丰度趋势与当地气温相似。线性判别分析效应大小（LEfSe）表明，有9个细菌属被认为是相应季节的生物标记。流动遗传元件（MGEs）与ARGs呈显着正相关（P <0.01），MGEs也被确定为导致ARG改变的关键因素。这项研究概述了近郊河流中ARGs分布的季节性和地理变化，并提请人们注意控制近郊生态系统中的污染物。