Abstract The effect of change of hydraulic characteristic and microbial community on pollution removal efficiency of the infiltration systems in the bioclogging development process remain poorly understood. In this study, therefore, the pollutant removal as a response to hydraulic conductivity reduction and the change of diversity and structure of microbial communities in vertical flow constructed wetlands (VFCWs) was investigated. The results indicated that the richness and diversity of the bacterial communities in the columns at different depths were decreased, and the microbial communities of the genus level were changed in the process of bioclogging. However, the variation of microbial communities has a low impact on the purification performance of VFCWs because the abundance of function groups, respiratory activity, and degradation potentiality of microorganisms remain steady or even get improved in the columns after bioclogging. On the contrary, the hydraulic efficiency of VFCWs decreased greatly by 16.9%, 9.9%, and 57.1% for VFCWs filled with zeolite (Column I), gravel (Column II), and ceramsite (Column III), respectively. The existence of short-circuiting and dead zones in the filter media cause the poor pollution removal efficiency of VFCWs due to the short contact time and decrease of oxygenation renewal, as well as low activity in the dead zone.

中文翻译：

---

生物堵塞对垂直流人工湿地污染去除效率的影响机制

摘要在生物堵塞发展过程中，水力特性和微生物群落的变化对渗透系统污染去除效率的影响仍知之甚少。因此，在本研究中，研究了垂直流人工湿地（VFCW）中污染物去除对水力传导率降低以及微生物群落多样性和结构变化的响应。结果表明，生物堵塞过程中，不同深度柱内细菌群落丰富度和多样性均下降，属级微生物群落发生变化。然而，微生物群落的变化对VFCW的净化性能影响较小，因为生物堵塞后柱中微生物的功能群丰度、呼吸活性和降解潜力保持稳定甚至得到改善。相反，填充沸石（I 柱）、砾石（II 柱）和陶粒（III 柱）的 VFCW 的水力效率分别大幅下降 16.9%、9.9% 和 57.1%。过滤介质中存在短路和死区，由于接触时间短、氧合更新减少以及死区活性低，导致VFCW去除污染物的效率较差。