Diurnal changes in bacterial communities in oxic surface and hypoxic middle seawater layers of the Changjiang River Estuary

Yan Huang; Lei Yuan; Yingping Fan; Habib U Rehman Jakhrani; Jianxin Wang

doi:10.1007/s13131-021-1778-2

Volume 40 Issue 4

Jun. 2021

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Yan Huang, Lei Yuan, Yingping Fan, Habib U Rehman Jakhrani, Jianxin Wang. Diurnal changes in bacterial communities in oxic surface and hypoxic middle seawater layers of the Changjiang River Estuary[J]. Acta Oceanologica Sinica, 2021, 40(4): 92-106. doi: 10.1007/s13131-021-1778-2

Citation:

Yan Huang, Lei Yuan, Yingping Fan, Habib U Rehman Jakhrani, Jianxin Wang. Diurnal changes in bacterial communities in oxic surface and hypoxic middle seawater layers of the Changjiang River Estuary[J]. Acta Oceanologica Sinica, 2021, 40(4): 92-106. doi: 10.1007/s13131-021-1778-2

Citation:

Yan Huang, Lei Yuan, Yingping Fan, Habib U Rehman Jakhrani, Jianxin Wang. Diurnal changes in bacterial communities in oxic surface and hypoxic middle seawater layers of the Changjiang River Estuary[J]. Acta Oceanologica Sinica, 2021, 40(4): 92-106. doi: 10.1007/s13131-021-1778-2

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Diurnal changes in bacterial communities in oxic surface and hypoxic middle seawater layers of the Changjiang River Estuary

doi: 10.1007/s13131-021-1778-2

Marine Microorganism Ecological & Application Laboratory, Zhejiang Ocean University, Zhoushan 316022, China

Funds: The National Key R&D Program of China under contract No. 2019YFD0901305; the Science and Technology Program of Zhoushan under contract No. 2019C21011; the National Natural Science Foundation of China under contract Nos 31270160 and J1310037; the Natural Science Foundation of Zhejiang Province, China under contract No. LY12C03003; the Zhejiang Public Welfare Technology Application Research Project under contract No. 2016C33084; the Research Project of Ecological Environment Protection and Restoration of Yangtze River in Zhoushan under contract No. SZGXZS2020068.

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Corresponding author: E-mail: jxwang@zjou.edu.cn
Received Date: 2019-11-22
Accepted Date: 2020-06-03

Available Online: 2021-04-29

Publish Date: 2021-04-25

Abstract

Abstract

The Changjiang River Estuary (CRE) in the East China Sea suffers from seasonal hypoxia in summer. The vertical distributions and seasonal changes of microbial communities in the CRE were well documented. However, little is known about the diurnal changes of bacterial communities in the hypoxic zone of the CRE. Here, 16S rRNA gene analysis was used to explore the changes of bacterial communities in the oxic surface and hypoxic middle seawater layers during 24 h in the CRE. Significant differences between the hypoxic and oxic layers were observed: the phyla Cyanobacteria, Bacteroidetes and Acidimicrobiia were enriched in the oxic layer, whereas the phylum SAR406 and the class Deltaproteobacteria were more abundant in the hypoxic layer. In addition, some subtle diurnal variations of the bacterial relative abundance were found in both two layers. The relative abundance of Synechococcus increased at night, and this change was more obvious in the hypoxic layer. The similar trend was also found in some phototrophic and several heterotrophic bacteria, such as Rhodobacteraceae, OM60 and Flavobacteriaceae. Their relative abundances peaked at 16:00 in the oxic layer, while the relative abundances peaked at around 7:00 and decreased until 13:00 in the hypoxic layer. Together, the results of the present study suggest that some photosynthetic bacteria and several heterotrophic bacteria have similar diurnal variations implying the light and physicochemical heterogeneity in the course of a day are important for bacterial diurnal changes in the CRE.
- bacterial communities,
- diurnal changes,
- hypoxic zone,
- the Changjiang River Estuary

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References(115)

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