Microbial abundance and activity of nitrite/nitrate-dependent anaerobic methane oxidizers in estuarine and intertidal wetlands: Heterogeneity and driving factors. (15th February 2021)

• Record Type: Journal Article
• Authors: Chen, Feiyang; Zheng, Yanling; Hou, Lijun; Niu, Yuhui; Gao, Dengzhou; An, Zhirui; Zhou, Jie; Yin, Guoyu; Dong, Hongpo; Han, Ping; Liang, Xia; Liu, Min
• Is Part Of: Water research. Volume 190(2021)
• Publication Date: 2021-02-15
• Subjects: Anaerobic methane oxidation -- Nitrate -- Nitrite -- Nitrogen elimination -- Intertidal sediment -- Yangtze Estuary; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2020.116737
• Languages: English
• ISSNs: 0043-1354

Abstract

Highlights: NO2−/NO3−-dependent anaerobic CH4 oxidation (n-DAMO) microbes are active in estuarine and intertidal wetlands n-DAMO bacteria contribute more to CH4 oxidation than n-DAMO archaea Abundance and role of n-DAMO microbes vary across estuarine habitats with different salinities n-DAMO microbial dynamics are associated closely with sediment characteristics Abstract: Nitrite/nitrate-dependent anaerobic methane oxidation (n-DAMO) is a crucial link between carbon and nitrogen cycles in estuarine and coastal ecosystems. However, the factors that affect the heterogeneous variability in n-DAMO microbial abundance and activity across estuarine and intertidal wetlands remain unclear. This study examined the spatiotemporal variations in n-DAMO microbial abundance and associated activity in different estuarine and intertidal habitats via quantitative PCR and 13 C stable isotope experiments. The results showed that Candidatus ' Methylomirabilis oxyfera ' ( M. oxyfera )-like DAMO bacteria and Candidatus ' Methanoperedens nitroreducens ' ( M. nitroreducens )-like DAMO archaea cooccurred in estuarine and intertidal wetlands, with a relatively higher abundance of the M. oxyfera -like bacterial pmoA gene (4.0 × 10 6 -7.6 × 10 7 copies g −1 dry sediment) than the M. nitroreducens -like archaeal mcrA gene (4.5 × 10 5 -9.4 × 10 7 copies g −1 dry sediment). The abundance of the M. oxyfera -like bacterial pmoA gene was closely associated with sediment pH and ammonium ( P <0.05), while no significant relationship was detected between M. nitroreducens -like archaeal mcrA gene abundance and the measured environmental parameters ( P >0.05). High n-DAMO microbial activity was observed, which varied between 0.2 and 84.3 nmol 13 CO2 g −1 dry sediment day −1 for nitrite-DAMO bacteria and between 0.4 and 32.6 nmol 13 CO2 g −1 dry sediment day −1 for nitrate-DAMO archaea. The total n-DAMO potential tended to be higher in the warm season and in the upstream freshwater and low-salinity estuarine habitats and was significantly related to sediment pH, total organic carbon, Fe(II), and Fe(III) contents ( P <0.05). In addition to acting as an important methane (CH4 ) sink, n-DAMO microbes had the potential to consume a substantial amount of reactive N in estuarine and intertidal environments, with estimated nitrogen elimination rates of 0.5-224.7 nmol N g −1 dry sediment day −1 . Overall, our investigation reveals the distribution pattern and controlling factors of n-DAMO bioprocesses in estuarine and intertidal marshes and gains a better understanding of the coupling mechanisms between carbon and nitrogen cycles. Graphical abstract: Image, graphical abstract