Nitrification inhibitor chlorate and nitrogen substrates differentially affect comammox Nitrospira in a grassland soil

作者：Anish Shah, Pei-Chun Hsu, Chris Chisholm, Andriy Podolyan, Keith C. Cameron, Jiafa Luo, Roland Stenger, Sam Carrick, Wei Hu, Scott Ferguson, Wenhua Wei, Ju‐Pei Shen, Limei Zhang, Hongbin Liu, Tongke Zhao, Wenxue Wei, Weixin Ding, Hong Pan, Yimeng Liu, Bowen Li, Jianjun Du, Hong J. Di · 发表于：Frontiers in Microbiology · 年份：2024 · DOI：10.3389/fmicb.2024.1392090 · 被引用次数：13 · 研究领域：Wastewater Treatment and Nitrogen Removal、Water Treatment and Disinfection、Microbial Community Ecology and Physiology

Introduction Through the combined use of two nitrification inhibitors, Dicyandiamide (DCD) and chlorate with nitrogen amendment, this study aimed to investigate the contribution of comammox Nitrospira clade B, ammonia oxidizing bacteria (AOB) and archaea (AOA) to nitrification in a high fertility grassland soil, in a 90-day incubation study. Methods The soil was treated with nitrogen (N) at three levels: 0 mg-N kg -1 soil, 50 mg-N kg -1 soil, and 700 mg-N kg -1 soil, with or without the two nitrification inhibitors. The abundance of comammox Nitrospira , AOA, AOB, and nitrite oxidising bacteria (NOB) was measured using qPCR. The comammox Nitrospira community structure was assessed using Illumina sequencing. Results and Discussion The results showed that the application of chlorate inhibited the oxidation of both NH 4 + and NO 2 - in all three nitrogen treatments. The application of chlorate significantly reduced the abundance of comammox Nitrospira amo A and nxr B genes across the 90-day experimental period. Chlorate also had a significant effect on the beta diversity (Bray-Curtis dissimilarity) of the comammox Nitrospira clade B community. Whilst AOB grew in response to the N substrate additions and were inhibited by both inhibitors, AOA showed litle or no response to either the N substrate or inhibitor treatments. In contrast, comammox Nitrospira clade B were inhibited by the high ammonium concentrations released from the urine substrates. These results demonstrate the diff...