Dissimilatory nitrate reduction to ammonium (DNRA) in traditional municipal wastewater treatment plants in China: Widespread but low contribution
Dissimilatory nitrate reduction to ammonium (DNRA) in traditional municipal wastewater treatment plants in China: Widespread but low contribution
复制标题
中国传统城市污水处理厂中的异化硝酸盐还原铵（DNRA）：广泛但贡献较低
DOI：
10.1016/j.watres.2020.115877
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发表时间：
2020
期刊：
影响因子：
12.8
通讯作者：
Zhu Guibing
中科院分区：
文献类型：
--
作者：
Wang Shanyun;Liu Chunlei;Wang Xiaoxia;Yuan Dongdan;Zhu Guibing
最近关于海洋、内陆水和土壤系统中异化硝酸盐还原为铵（DNRA）的发生和贡献的报道极大地提高了我们对全球氮（N）循环的理解。这也促进了对DNRA在人类生态系统中的作用和生态特征的研究。然而，到目前为止，DNRA在城市污水处理厂（WWTPs）中的使用，这是最常见和最大的生物技术人工水生态系统之一，尚未进行调查。因此，本研究的重点是在全面的污水处理厂的DNRA细菌的丰度，活性，群落结构和多样性。在六个测试的市政污水处理厂的所有处理单元中检测到DNRA细菌，甚至在好氧区（溶解氧> 2 mg L-1）。虽然DNRA细菌的相对丰度（0.2-4.0%）低于硝化细菌的相对丰度（0.7-10.1%），但DNRA细菌的丰度仍达到10（9）个基因拷贝g（-1）。15-氮同位素示踪结果表明，DNRA的潜在速率（0.4-2.1 nmol Ng（-1）h（-1））显著低于反硝化速率（9.5-15.7 nmol Ng（-1）h（-1）），但高于厌氧氨氧化速率（0.3-1.3 nmol Ng（-1）h（-1））。尽管有处理过程，DNRA细菌群落结构主要受到温度梯度的影响。针对DNRA nrfA基因的高通量测序分析显示，在所有样品中，Nitrospira占nrfA基因的比例最大（6.2-36.3%），其次是Brocadia（5.9-22.1%）。网络分析进一步表明，硝化螺菌在城市污水处理厂的DNRA细菌群落和整个细菌群落中起着重要作用。这些结果表明，DNRA细菌在人类生态系统中的生态栖息地比以前假设的要丰富得多。然而，在传统的城市污水处理厂中，广泛分布的DNRA对氮转化的贡献并不显著。(c)2020爱思唯尔有限公司保留所有权利。
Recent reports on the occurrence and contribution of dissimilatory nitrate reduction to ammonium (DNRA) in marine, inland water, and soil systems have greatly improved our understanding of the global nitrogen (N) cycle. This also promoted the investigation of the role and ecological features of DNRA in anthropogenic ecosystems. However, so far, the use of DNRA in municipal wastewater treatment plants (WWTPs), which are one of the most common and largest biotechnologically artificial water ecosystems, has not been investigated. Accordingly, this study focused on the abundance, activity, community structure, and diversity of DNRA bacteria in full-scale WWTPs. DNRA bacteria were detected in all treatment units in six tested municipal WWTPs, even in aerobic zones (dissolved oxygen > 2 mg L-1). Although the relative abundance of DNRA bacteria (0.2-4.0%) was less than that of denitrifying bacteria (0.7-10.1%) among all investigated samples, the abundance of DNRA bacteria still reaches 10(9) gene copies g(-1). However, N-15-isotope tracing indicated that the potential DNRA rates were significantly lower (0.4-2.1 nmol N g(-1) h(-1)) than those of denitrification (9.5-15.7 nmol N g(-1) h(-1)), but higher than anammox rate (0.3-1.3 nmol N g(-1) h(-1)). The DNRA bacterial community structure was primarily affected by temperature gradient despite the treatment process. High-throughput sequencing analysis targeting the DNRA nrfA gene showed that Nitrospira accounted for the largest proportion of nrfA genes among all samples (6.2-36.3%), followed by Brocadia (5.9-22.1%). Network analysis further indicated that Nitrospira played an important role in both the DNRA bacterial community and entire bacterial community in municipal WWTPs. These results suggest that the ecological habitats of DNRA bacteria in anthropogenic ecosystems were far more abundant than previously assumed. However, the contribution to N transformation by the widespread DNRA was not significant in traditional municipal WWTPs. (c) 2020 Elsevier Ltd. All rights reserved.