The pollution of wastewater with antibiotics and antibiotics resistance genes has attracted public concerns about ecosystem and global health. Swine wastewater can contain high concentrations of antibiotics, especially sulfonamides, even after full-scale wastewater treatment. In this study, mesocosm-scale vertical flow constructed wetlands (VF-CWs) were applied to abate nutrients and antibiotics in swine wastewater containing sulfonamides. VF-CWs performed well in the removal of both nutrients and antibiotics. Sulfonamides did not influence total organic carbon (TOC) and total phosphorus (TP) removal, and even slightly enhanced NH₄⁺–N removal. High removal efficiencies (26.42–84.05%) were achieved for sulfadiazine (SDZ), sulfamethoxazole (SMX) and sulfamethazine (SMZ). Together with lab-scale sorption and biodegradation experiments, microbial degradation was found to be the most important removal mechanism for sulfonamides in VF-CWs. Sulfonamides addition increased bacterial alpha-diversity and changed microbial community structure. Moreover, antibiotics promoted antibiotic-resistant or -degrading bacteria. Bacillus, Geobacter and other seven genera were correlated with sulfonamides reduction under either aerobic or anaerobic condition. In summary, VF-CW is a suitable alternative for swine wastewater treatment, and biodegradation plays the key role in sulfonamides abatement.

Main findings of the work.

This was the first work to combine bacterial community analysis with microcosm experiments to uncover the major removal mechanism of sulfonamides in constructed wetlands.

抗生素和抗生素抗性基因对废水的污染引起了公众对生态系统和全球健康的关注。猪废水即使经过全面废水处理，也可能含有高浓度的抗生素，尤其是磺酰胺。在这项研究中，中尺度规模的垂直流人工湿地（VF-CWs）被用于减少猪体内含磺酰胺废水中的营养和抗生素。VF-CW在去除营养和抗生素方面表现良好。磺酰胺不会影响总有机碳（TOC）和总磷（TP）的去除，甚至不会稍微提高NH ₄ ⁺–N去除。磺胺嘧啶（SDZ），磺胺甲恶唑（SMX）和磺胺二甲嘧啶（SMZ）的去除效率高（26.42-84.05％）。连同实验室规模的吸附和生物降解实验，发现微生物降解是VF-CWs中磺酰胺最重要的去除机理。磺胺类药物的添加增加了细菌的α多样性并改变了微生物群落结构。而且，抗生素促进了抗生素抗性或降解细菌。在有氧或无氧条件下，芽孢杆菌，地杆菌和其他七个属与磺酰胺的减少有关。总之，VF-CW是猪废水处理的合适替代品，生物降解在减少磺酰胺中起关键作用。

工作的主要发现。

这是将细菌群落分析与微观实验相结合以揭示人工湿地中磺胺类药物主要清除机制的第一项工作。