Mu Xiaoying, Chen Congli, Fan Qinya, Zhang Weihang, Liu Fei, Guo Jiaxun, Qi Weixiao, Liu Huijuan
Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Yangtze Eco-Environment Engineering Research Center, China Three Gorges Corporation, Wuhan 430010, China.
Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
Sci Total Environ. 2025 Jan 1;958:178034. doi: 10.1016/j.scitotenv.2024.178034. Epub 2024 Dec 14.
Sulfamethoxazole (SMX) and its human metabolite N-acetylsulfamethoxazole (N-SMX) are frequently detected in aquatic environments, posing potential threats to freshwater ecosystem health. Constructed wetlands are pivotal for wastewater treatment, with plant species serving as key determinants of pollutant removal efficiency. In this study, wetlands dominated by three submerged plants (Myriophyllum verticillatum, Vallisneria spiralis, Hydrilla verticillata) were respectively constructed to investigate the removal of SMX and N-SMX, and the impact on wetland ecology regarding plant tolerance, microbial response, and nitrogen transformation. Results showed that wetlands removed N-SMX (82.3-99.8 %) more effectively than SMX (54.3-80.2 %), with the wetland dominated by Myriophyllum verticillatum showing the highest removal efficiency. However, high concentrations (5 mg/L) of SMX and N-SMX significantly reduced NH-N and TN removal (p < 0.05), accompanied by shifts in microbial communities, especially a decreased abundance of Proteobacteria and key nitrogen-transforming genes. A total of 22 different ARGs (antibiotic resistance genes) were detected. SMX significantly increased the relative abundance of sulfonamide resistance genes (sul1, sul2) (p < 0.05), while major denitrifying genera, such as Thiobacillus, which were not the primary hosts of these genes, showed a significant negative correlation with sul1 and sul2 (p < 0.05). This study provides a reference for ecological remediation of wetlands in response to antibiotic contamination.
磺胺甲恶唑（SMX）及其人体代谢产物N - 乙酰磺胺甲恶唑（N - SMX）在水生环境中经常被检测到，对淡水生态系统健康构成潜在威胁。人工湿地对于污水处理至关重要，植物种类是污染物去除效率的关键决定因素。在本研究中，分别构建了以三种沉水植物（轮叶黑藻、苦草、黑藻）为主的湿地，以研究SMX和N - SMX的去除情况，以及对湿地生态在植物耐受性、微生物反应和氮转化方面的影响。结果表明，湿地对N - SMX（82.3 - 99.8%）的去除效果比对SMX（54.3 - 80.2%）更有效，其中以轮叶黑藻为主的湿地去除效率最高。然而，高浓度（5 mg/L）的SMX和N - SMX显著降低了NH - N和TN的去除率（p < 0.05），同时伴随着微生物群落的变化，尤其是变形菌门丰度的降低以及关键氮转化基因的减少。总共检测到22种不同的抗生素抗性基因（ARGs）。SMX显著增加了磺胺抗性基因（sul1、sul2）的相对丰度（p < 0.05），而主要的反硝化菌属，如硫杆菌属，它们并非这些基因的主要宿主，与sul1和sul2呈现显著负相关（p < 0.05）。本研究为应对抗生素污染的湿地生态修复提供了参考。
