Research Center for Coastal Environment Engineering Technology of Shandong Province, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, China.
Research Center for Coastal Environment Engineering Technology of Shandong Province, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, China.
Ecotoxicol Environ Saf. 2023 Sep 15;263:115234. doi: 10.1016/j.ecoenv.2023.115234. Epub 2023 Jul 6.
Functional bacterial communities (FBC) have members of different taxonomic biochemical groups, such as N-fixation, nitrification and denitrification. This study explored the mechanism of the FBC from an upflow three-dimensional biofilm electrode reactor on enhancing the nitrogen removal efficiencies in a Sesuvium potulacastum (S. potulacastum) constructed wetland. There were high abundances of denitrifying bacteria detected in the FBC, and they had potential metabolic processes for nitrogen reduction. In the constructed wetland, cellular nitrogen compounds of S. potulacastum were enriched by overexpressed differentially expressed genes (DEGs), and the napA, narG, nirK, nirS, qnorB, and NosZ genes related to the denitrification process had more copies under FBC treatment. Nitrogen metabolism in root bacterial communities (RBCs) was activated in the FBC group compared with the control group without FBC. Finally, these FBCs improved the removal efficiencies of DTN (dissolved total nitrogen), NO-N, NO-N, and NH-N by 84.37 %, 87.42 %, 67.51 %, and 92.57 %, respectively, and their final concentrations met the emission standards of China. These findings indicate that adding FBC into S. potulacastum-constructed wetlands would result in high nitrogen removal efficiencies from wastewater and have large potential applications in further water treatment technology.
功能细菌群落（FBC）有不同分类学生化群的成员，例如固氮、硝化和反硝化。本研究从上升流三维生物膜电极反应器中探索了 FBC 的机制，该反应器可提高 Sesuvium potulacastum（S. potulacastum）人工湿地的氮去除效率。在 FBC 中检测到大量的反硝化细菌，它们具有潜在的氮还原代谢过程。在人工湿地中，S. potulacastum 的细胞氮化合物通过过度表达差异表达基因（DEGs）得到富集，并且与反硝化过程相关的 napA、narG、nirK、nirS、qnorB 和 NosZ 基因在 FBC 处理下具有更多的副本。与没有 FBC 的对照组相比，FBC 组中根细菌群落（RBC）中的氮代谢被激活。最后，这些 FBC 将 DTN（溶解总氮）、NO-N、NO-N 和 NH-N 的去除效率分别提高了 84.37%、87.42%、67.51%和 92.57%，其最终浓度达到了中国的排放标准。这些发现表明，将 FBC 添加到 S. potulacastum 人工湿地中会导致废水的氮去除效率很高，并且在进一步的水处理技术中有很大的应用潜力。
