由于各种基质之间的复杂相互作用,人工湿地(CW)中发生的微生物过程难以理解。微生物,和植物在给定的物理化学条件下。这经常导致这些系统中非常大的无法解释的氮损失。在继续我们关于Anammox贡献的发现中,我们对全尺度场CWs的研究表明,在湿地中发生的常规C-N循环中,硫循环的显着参与,这可能很好地解释了这些系统中的氮损失。本文探讨了硫驱动自养反硝化(SDAD)途径在不同类型的CW中的可能性,浅、深、被动和充气系统,通过分析这些CW中存在的宏基因组细菌群落。结果表明,与浅层系统相比,深层被动系统中SDAD细菌(副杆菌属和芽孢杆菌)的丰度更高,并且存在大量SDAD属(副杆菌属,硫杆菌,Beggiatoa,硫单胞菌,弓形虫,和Sulfuricurvum)在充气CW中。发现属于硫化合物暗氧化功能类别的细菌富含深层充气CW,暗示了SDAD途径在这些系统中总氮去除中的可能作用。作为一个案例研究,在充气湿地中,通过SDAD途径的氮去除百分比计算为15-20%。氮去除的自养途径的存在可以证明在减少污泥生成和减少堵塞方面非常有益。使曝气CW成为可持续的废水处理解决方案。
The microbial processes occurring in constructed wetlands (CWs) are difficult to understand owing to the complex interactions occurring between a variety of substrates, microorganisms, and plants under the given physicochemical conditions. This frequently leads to very large unexplained nitrogen losses in these systems. In continuation of our findings on Anammox contributions, our research on full-scale field CWs has suggested the significant involvement of the sulfur cycle in the conventional C-N cycle occurring in wetlands, which might closely explain the nitrogen losses in these systems. This paper explored the possibility of the sulfur-driven autotrophic denitrification (SDAD) pathway in different types of CWs, shallow and deep and passive and aerated systems, by analyzing the metagenomic bacterial communities present within these CWs. The results indicate a higher abundance of SDAD bacteria (Paracoccus and Arcobacter) in deep passive systems compared to shallow systems and presence of a large number of SDAD genera (Paracoccus, Thiobacillus, Beggiatoa, Sulfurimonas, Arcobacter, and Sulfuricurvum) in aerated CWs. The bacteria belonging to the functional category of dark oxidation of sulfur compounds were found to be enriched in deep and aerated CWs hinting at the possible role of the SDAD pathway in total nitrogen removal in these systems. As a case study, the percentage nitrogen removal through SDAD pathway was calculated to be 15-20% in aerated wetlands. The presence of autotrophic pathways for nitrogen removal can prove highly beneficial in terms of reducing sludge generation and hence reducing clogging, making aerated CWs a sustainable wastewater treatment solution.