| 人工生态系统对城市河流中抗生素和ARGs的去除 |
| 摘要点击 2087 全文点击 696 投稿时间：2020-07-05 修订日期：2020-07-31 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 挺水植物 抗生素 抗生素抗性基因 铜绿微囊藻 冗余分析 城市河流 |
| 英文关键词 emergent plant antibiotics antibiotic resistance genes Microcystis aeruginosa redundancy analysis urban rivers |
|
| 中文摘要 |
| 通过室内模拟河道系统，以阿奇霉素（AZM）、磺胺甲唑（SMZ）、环丙沙星（CIP）和四环素（TCY）这4种抗生素和抗性基因（ARGs）：磺胺类（sul1和sul2）、四环素类（tetX和tetM）、喹诺酮类（qnrS和qnrD）、大环内酯类（ermB）和16S rDNA为目标物，研究2种挺水植物和铜绿微囊藻组合（菖蒲+灯芯草、藻+灯芯草、藻+菖蒲和藻+菖蒲+灯芯草）的人工生态系统不同介质（水相、泥相和植物）中抗生素的变化特性、对常规污染物（COD、NH4+-N、TP和TN）的去除效果以及在水相和泥相中ARGs的分布和去除效果.并通过物料衡算计算目标物的实际去除率，以及分析水相和泥相中ARGs丰度与环境因子之间的相关性.结果表明，所形成的人工生态系统对COD、NH4+-N、TP和TN去除率范围分别为60.2%~74.8%、63.4%~77.4%、64.0%~73.2%和46.8%~54.8%；对水相中抗生素有明显的去除效果，藻+菖蒲+灯芯草组合的人工生态系统对4种抗生素去除率最好；对泥相中抗生素去除率依次为TCY > CIP > AZM > SMZ，其中藻+菖蒲+灯芯草组合对TCY去除率达到53.5%；对抗生素的实际总去除率大小依次为藻+菖蒲+灯芯草 > 藻+灯芯草 > 藻+菖蒲 > 菖蒲+灯芯草.4类ARGs去除效果较明显，水相中的去除率要高于泥相；ARGs与常规污染物以及抗生素之间存在不同的相关性，其中水相中tetX与环境因子、泥相中AZM与之对应ARGs的相关性不显著，说明ARGs既可以在对应抗生素压力下选择，也可以在其他类型环境压力下选择，抗生素含量并不是直接影响ARGs的传播.本研究表明挺水植物和铜绿微囊藻组合的人工生态系统可作为净化水质和改善城市河流中抗生素环境风险的有效手段. |
| 英文摘要 |
| Four antibiotics[azithromycin (AZM), sulfamethoxazole (SMZ), ciprofloxacin (CIP), and tetracycline (TCY)], and the antibiotic resistance genes (ARGs)[sulfonamides (sul1 and sul2), tetracyclines (tetX and tetM), quinolones (qnrS and qnrD), macrolides (ermB), and 16S rDNA] were selected as target compounds. Artificial ecosystems were constructed with combinations of two emergent plants and Microcystis aeruginosa (Acorus calamus+Cordyceps, algae+Cordyceps, algae+Acorus calamus, and algae+Acorus calamus+Cordyceps) in an indoor-simulated river system. Throughout the artificial ecosystems, changes in antibiotic concentrations and other pollution indicators (i.e., COD, NH4+-N, TP, and TN) were monitored in different media (the aqueous phase, sediment phase, and in plants), and the distribution and removal of ARGs in aqueous and sediment phases were explored. Removal of the target compounds was calculated based on mass balance, and the correlation between ARG abundance and environmental factors in the aqueous and sediment phases was analyzed. The results showed that the constructed artificial ecosystem achieved removal rates of COD, NH4+-N, TP, and TN ranging from 60.2% to 74.8%, 63.4% to 77.4%, 64.0% to 73.2%, and 46.8% to 54.8%, respectively. The antibiotics in the aqueous phase were notably removed and the artificial ecosystem ‘algae+Acorus calamus+Cordyceps’ achieved the best removal efficiency for the four antibiotics. Removal rates of the antibiotics in the sediment phase were ranked in the order TCY>CIP>AZM>SMZ; the removal efficiency of TCY in the ‘algae+Acorus calamus+Cordyceps’ system reached up to 53.5%. The total removal rates of antibiotics obtained by the ecosystems were ranked in the following order:algae+Acorus calamus+Cordyceps > algae+Cordyceps > algae+Acorus calamus > Acorus calamus+Cordyceps. Removal of the four ARGs was very efficient and was higher in the aqueous phase than in the sediment phase. Correlations between the ARGs, the other pollution indicators, and the antibiotics were variable; tetX and environmental factors were correlated in the aqueous phase, while AZM and its corresponding ARGs were not significantly correlated in the sediment phase. The results showed that ARGs can be targeted under corresponding antibiotic pressure and other types of environmental pressure. In the study system, the concentrations of antibiotics did not directly affect the transmission of ARGs. Overall, this study shows that artificial ecosystems constructed with emergent plants and Microcystis aeruginosa can be effective at purifying water and reducing the environmental risks of antibiotics in urban rivers. |
|
|
|
