Research Center of Hydrobiology, Department of Ecology, Jinan University, Guangzhou 510632, China; Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Guangzhou 510632, China.
School of Science and Technology, The Open University of Hong Kong, Ho Man Tin, Kowloon, Hong Kong.
Bioresour Technol. 2020 Dec;318:124061. doi: 10.1016/j.biortech.2020.124061. Epub 2020 Sep 2.
The mechanisms of bacterial nitrogen (N), phosphorus (P), and chemical oxygen demand (COD) removal in pilot-scale constructed wetlands (CWs) were investigated in the present work. Three types of CWs were assessed: vertical flow (VF), horizontal flow (HF), and surface flow (SF), each with three planting conditions, with either Thalia, Canna or without plants. The results show that construction types affected microbes more than planting conditions. VF CWs promoted the aerobic processing of total N, total P, COD, and NH-N, increasing the respective removal efficiencies by 4-19%, 13-32%, 19-29%, and 75-80%, respectively, compared with SF CWs. The relative abundance of nitrifying, denitrifying, methanotrophic and dephosphorized bacteria, and functional genes such as nxrA, nirK, nosZ, mmoX, and phoD were higher in VF CWs. Positive and simple gene networks in VF CWs can effectively reduce the redundancy in functional genes, enhance bacterial function and gene interactions, thus promoting nutrient removal.
本研究考察了中试规模人工湿地（CWs）中细菌氮（N）、磷（P）和化学需氧量（COD）去除的机制。评估了三种类型的 CWs：垂直流（VF）、水平流（HF）和表面流（SF），每种类型都有三种种植条件，分别为有香蒲、美人蕉或无植物。结果表明，结构类型对微生物的影响大于种植条件。与 SF CWs 相比，VF CWs 促进了总 N、总 P、COD 和 NH-N 的好氧处理，分别提高了各自的去除效率 4-19%、13-32%、19-29%和 75-80%。硝化、反硝化、甲烷氧化和除磷细菌的相对丰度以及 nxrA、nirK、nosZ、mmoX 和 phoD 等功能基因在 VF CWs 中更高。VF CWs 中的正简单基因网络可以有效减少功能基因的冗余，增强细菌功能和基因相互作用，从而促进养分去除。
