https://hdl.handle.net/10680/1323 2022-07-20T20：48：46Z 2022-07-20T20：48：46Z Anderson, Julie C. 卡尔森，朱尔斯·C。 Low，Jennifer E. Challis, Jonathan K. Wong, Charles S. Knapp, Charles W. Hanson, Mark L. https://hdl.handle.net/10680/1326 2019-06-24T21：42：36z 2013 - 01 - 01 - t00:00:00z

在加拿大曼尼托巴省大马莱的建造湿地的性能：从市政废水中去除营养素，药品和抗生素耐药基因Anderson, Julie C.; Carlson, Jules C.; Low, Jennifer E.; Challis, Jonathan K.; Wong, Charles S.; Knapp, Charles W.; Hanson, Mark L. BACKGROUND: The discharge of complex mixtures of nutrients, organic micropollutants, and antibiotic resistance genes from treated municipal wastewater into freshwater systems are global concerns for human health and aquatic organisms. Antibiotic resistance genes (ARGs) are genes that have the ability to impart resistance to antibiotics and reduce the efficacy of antibiotics in the systems in which they are found. In the rural community of Grand Marais, Manitoba, Canada, wastewater is treated passively in a sewage lagoon prior to passage through a treatment wetland and subsequent release into surface waters. Using this facility as a model system for the Canadian Prairies, the two aims of this study were to assess: (a) the presence of nutrients, micropollutants (i.e., pesticides, pharmaceuticals), and ARGs in lagoon outputs, and (b) their potential removal by the treatment wetland prior to release to surface waters in 2012. RESULTS: As expected, concentrations of nitrogen and phosphorus species were greatest in the lagoon and declined with movement through the wetland treatment system. Pharmaceutical and agricultural chemicals were detected at concentrations in the ng/L range. Concentrations of these compounds spiked downstream of the lagoon following discharge and attenuation was observed as the effluent migrated through the wetland system. Hazard quotients calculated for micropollutants of interest indicated minimal toxicological risk to aquatic biota, and results suggest that the wetland attenuated atrazine and carbamazepine significantly. There was no significant targeted removal of ARGs in the wetland and our data suggest that the bacterial population in this system may have genes imparting antibiotic resistance. CONCLUSIONS: The results of this study indicate that while the treatment wetland may effectively attenuate excess nutrients and remove some micropollutants and bacteria, it does not specifically target ARGs for removal. Additional studies would be beneficial to determine whether upgrades to extend retention time or alter plant community structure within the wetland would optimize removal of micropollutants and ARGs to fully characterize the utility of these systems on the Canadian Prairies.

2013 - 01 - 01 - t00:00:00z 歌手安德鲁·C（Andrew C.） Wong, Charles S. 克劳利，大卫·E。 https://hdl.handle.net/10680/1325 2019-06-24T21:42:55Z 2002 - 11 - 01 - t00:00:00z

Differential Enantioselective Transformation of Atropisomeric Polychlorinated Biphenyls by Multiple Bacterial Strains with Different Inducing Compounds Singer, Andrew C.; Wong, Charles S.; Crowley, David E. Enantioselective biotransformation of polychlorinated biphenyls (PCBs) has been suggested from studies showing differential occurrence of PCB enantiomers in environmental samples, including river and riparian biota and sediments. To date, however, there has been only a single study in the literature that has examined enantioselectivity by a PCB-degrading microorganism.

2002 - 11 - 01 - t00:00:00z Stolzenbach，Keith D. Newman, Kathleen A. Wong, Charles S. https://hdl.handle.net/10680/1324 2019-06-24T21:43:12Z 1992-11-15T00：00：00z

在沉积物 - 水界面stolzenbach，Keith d。的细颗粒聚集。纽曼，凯瑟琳A。Wong，Charles S.通过机械搅拌或常驻有机体（Tubificid寡聚体）搅拌的底部沉积物层的存在显着提高了从实验室柱中的悬浮液中除去罚款（1 µm）内粘性颗粒的速率。测得的颗粒去除速率等效于从每天0.23 m到每天0.41 m的沉积速度。这些速率是通过在实验对照中观察到的水柱中的重力沉降或与较大颗粒的重力沉降或与较大的颗粒凝结快的数量级。假设增加的去除率是在床 - 水界面处沉积物层聚集的结果，其特征是松散结合（蓬松的）多孔材料流体动力学与水柱耦合。根据这种假设的去除，就会发生颗粒或有机体活动的运动导致悬浮的细颗粒与碰撞并粘在界面沉积物上时。这一新假设得到了在沿海地区和界面聚集率的理论估计中回收的芯和沉积物陷阱中回收的示踪剂颗粒的质量和尺寸分布。

1992-11-15T00：00：00z