Effects of Potamogeton crispus decline in the rhizosphere on the abundance of anammox bacteria and nirS denitrifying bacteria☆. (May 2020)

• Record Type: Journal Article
• Authors: Hu, Jinlong; Zhou, Yuhao; Lei, Ziyan; Liu, Guanglong; Hua, Yumei; Zhou, Wenbing; Wan, Xiaoqiong; Zhu, Duanwei; Zhao, Jianwei
• Is Part Of: Environmental pollution. Volume 260(2020)
• Publication Date: 2020-05
• Subjects: Rhizosphere sediment -- Submerged macrophyte -- Sudden decline -- nirS denitrifying bacteria -- Anammox bacteria; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2020.114018
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Bacteria involved with ecosystem N cycling in the rhizosphere of submerged macrophytes are abundant and diverse. Any declines of submerged macrophytes can have a great influence on the abundance and diversity of denitrifying bacteria and anammox bacteria. Natural decline, tardy decline, and sudden decline methods were applied to cultivated Potamogeton crispus . The abundance of anammox bacteria and nirS denitrifying bacteria in rhizosphere sediment were detected using real-time fluorescent quantitative PCR of 16S rRNA, and phylogenetic trees were constructed to analyze the diversities of these two microbes. The results indicated that the concentration of NH4 + in pore water gradually increased with increasing distances from the roots, whereas, the concentration of NO3 − showed a reverse trend. The abundance of anammox bacteria and nirS denitrifying bacteria in sediment of declined P. crispus populations decreased significantly over time. The abundance of these two microbes in the sudden decline group were significantly higher (P > 0.05) than the other decline treatment groups. Furthermore, the abundances of these two microbes were positively correlated, with RDA analyses finding the mole ratio of NH4 + /NO3 − being the most important positive factor affecting microbe abundance. Phylogenetic analysis indicated that the anammox bacteria Brocadia fuigida and Scalindua wagneri, and nirS denitrifying bacteria Herbaspirillum and Pseudomonas, were the dominant species in declined P. crispus sediment. We suggest the sudden decline of submerged macrophytes would increase the abundance of anammox bacteria and denitrifying bacteria in a relatively short time. Highlights: P. crispus decline significantly decreased the abundance of anammox bacteria and nirS . Abundance of two microbes in sediment were significantly difference in each group. Two microbe abundances were positively correlated in the sediment of the sudden decline group. NH4 + /NO3 − was significantly positive related with the abundances of these two microbe types.