College of Water Sciences, Beijing Normal University, Beijing 100875, China.
College of Water Sciences, Beijing Normal University, Beijing 100875, China.
Ecotoxicol Environ Saf. 2022 Dec 15;248:114347. doi: 10.1016/j.ecoenv.2022.114347. Epub 2022 Nov 28.
As a green technology, constructed wetlands (CWs) can provide a low-cost solution for wastewater treatment. Either as a standalone treatment or integrated with conventional treatment, nutrients, antibiotic resistant bacteria (ARB)/antibiotic resistance genes (ARGs) can be removed by CW efficiently. While, few studies have focused on characteristics of resistome and bacterial community (BC) structure in CW during dormant period. Therefore, in this study, Annan CW (a full-scale hybrid CW) was selected to characterize resistome and BC during dormant period. The profiles of bacteria / ARGs were monitored in combination of shotgun sequencing and metagenomic assembly analysis. And multidrug ARGs are the most abundant in Annan CW, and surface flow wetland had the relatively high ARG diversity and abundance compared with subsurface flow wetland and the front pond. The most dominant phylum in CW is Proteobacteria, while the other dominant phylum in three parts have different order. COD, TP, TN, ARGs, and mobile genetic genes (MGEs) were removed by subsurface flow CW with better performance, but virulent factors (VFs) were removed by surface flow CW with better performance. Based on the spatiotemporal distribution of ARGs, the internal mechanism of ARGs dynamic variation was explored by the redundancy analysis (RDA) and variation partitioning analysis (VPA). BCs, MGEs and environmental factors (EFs) were responsible for 45.6 %, 28.3 % and 15.4 % of the ARGs variations. Among these factors, BCs and MGEs were the major co-drivers impacting the ARG profile, and EFs indirectly influence the ARG profile. This study illustrates the specific functions of ARG risk elimination in different CW components, promotes a better understanding of the efficiency of CWs for the reduction of ARG and ARB, contributing to improve the removal performance of constructed wetlands. And provide management advice to further optimize the operation of CWs during dormant period.
作为一种绿色技术，人工湿地 (CWs) 可为废水处理提供低成本解决方案。无论是作为单独的处理方法还是与传统处理方法结合使用，CWs 都可以有效地去除营养物质、抗生素抗性细菌 (ARB)/抗生素抗性基因 (ARGs)。然而，很少有研究关注 CWs 在休眠期的抗药性组和细菌群落 (BC) 结构特征。因此，在这项研究中，选择安南 CW（全规模混合 CW）来表征休眠期的抗药性组和 BC。结合鸟枪法测序和宏基因组组装分析，监测细菌/ARGs 的分布。在安南 CW 中，多药 ARGs 最为丰富，与地下流湿地相比，地表流湿地的 ARG 多样性和丰度较高，而前塘的 ARG 多样性和丰度较高。CW 中最主要的门是变形菌门，而其他三个部分的主要门顺序不同。COD、TP、TN、ARGs 和移动遗传基因 (MGEs) 经地下流 CW 去除效果较好，但毒力因子 (VF) 经地表流 CW 去除效果较好。基于 ARGs 的时空分布，通过冗余分析 (RDA) 和变异分解分析 (VPA) 探讨了 ARGs 动态变化的内在机制。BCs、MGEs 和环境因子 (EFs) 分别对 ARGs 变化的 45.6%、28.3%和 15.4%负责。在这些因素中，BCs 和 MGEs 是影响 ARG 图谱的主要共同驱动因素，而 EFs 间接影响 ARG 图谱。本研究说明了不同 CW 组件中 ARG 风险消除的具体功能，促进了对 CWs 减少 ARG 和 ARB 效率的更好理解，有助于提高人工湿地的去除性能。并为进一步优化 CWs 在休眠期的运行提供管理建议。
