AUTHOR=Teng Zhenzhen , Zhen Yu , Yu Zhigang , Mi Tiezhu , Cai Tao 

TITLE=Nitrogen-loss and associated microbial communities in sediments from the Yangtze Estuary and adjacent sea

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2022.1078653

DOI=10.3389/fmars.2022.1078653

ISSN=2296-7745

ABSTRACT=Denitrification and anammox play the crucial role for N removal processes in coastal 18
ecosystems, but the ecological distribution of denitrifying and anammox 19
microorganisms and their N removal rates in the Yangtze Estuary and its adjacent sea 20
are required in-depth analysis. Here, we utilized high-throughput sequencing, qPCR, 21
and 15N isotope to reveal the community structure and function of denitrifying and 22
anammox microorganisms in the surface sediments from Yangtze Estuary and 23
adjacent sea. The results suggested that the gene abundances of nirS and nirK for 24
denitrifiers were higher than AMX 16S rRNA for anammox bacteria. The genera 25
composition of nirS- and nirK-encoding denitrifiers communities showed different 26
distribution patterns. Furthermore, Candidatus Anammoximicrobium dominated the 27
anammox community, implying the anammox oxidation capacity of the other genera 28
should be noted in marine sediments. Compared to anammox, denitrification was the 29
dominant contributor of nitrogen removal process and contributed 73.5% on average. 30
The sediment Chla was the key factor to regulate denitrification and anammox rates, 31
indicating the fresh organic matter was more labile and easier to be utilized by NOx− removal processes.