Influencing factors of antibiotic resistance genes removal in constructed wetlands: A meta-analysis assisted by multivariate statistical methods

In order to control antibiotic resistance genes (ARGs) diffusion in constructed wetlands, it is critical to explore the main factors influencing ARGs removal and understand its mechanism. Despite the fact that numerous studies have been conducted to determine the factors influencing ARGs removal by constructed wetlands in recent years, attempts to use published data and incorporate them into a comprehensive comparison and analysis are still limited. A framework for literature collection, data extraction and statistical analysis (LDS) was constructed in this study. The main factors influencing antibiotics and ARGs removal by constructed wetlands were identified using this framework. The results showed that nutrients, types of constructed wetlands and hydraulic loading were the principal factors influencing the removal of most antibiotics. The principal factors influencing the most ARGs removal were mobile genetic elements, plants, volume of constructed wetlands and running time. After purification by constructed wetlands, the risk coefficient of antibiotics decreased significantly, while the relative abundance of most ARGs did not change significantly. The analysis results of linear mixed model showed that the relationship between antibiotics and ARGs in effluent was closer than that in influent. LDS framework provides a new platform for the study of influencing factors of pollutant removal based on data mining.