文献类型：期刊文献

英文题名：Response of nir-type rhizosphere denitrifier communities to cold stress in constructed wetlands with different water levels

作者：Wang, Rumiao[1,2] Cui, Lijuan[1,2] Li, Jing[1,2] Li, Wei[1,2] Zhu, Yinuo[1,2] Hao, Ting[1,2] Liu, Zhijun[1,2] Lei, Yinru[1,2] Zhai, Xiajie[1,2] Zhao, Xinsheng[1,2]

第一作者：Wang, Rumiao

通信作者：Cui, LJ[1];Cui, LJ[2]

机构：[1]Chinese Acad Forestry, Inst Wetland Res, Beijing Key Lab Wetland Ecol Funct & Restorat, Beijing 100091, Peoples R China;[2]Beijing Hanshiqiao Natl Wetland Ecosyst Res Stn, Beijing 101399, Peoples R China

年份：2022

卷号：362

外文期刊名：JOURNAL OF CLEANER PRODUCTION

收录：;EI(收录号：20222212174130);Scopus(收录号：2-s2.0-85130769112);WOS:【SCI-EXPANDED(收录号:WOS:000810028100001)】；

基金：Acknowledgements This work was supported by the Beijing Natural Science Foundation, China (8214067) .

语种：英文

外文关键词：Cold stress; Constructed wetland; Water level; Denitrifier community composition

摘要：Constructed wetlands (CWs) are used to remove nitrogen-containing organic pollutants based on the roles of plant and microbial communities. However, the rhizosphere nitrogen removal process and microbial response to cold stress in CWs in winter remain unclear. In this study, we investigated the potential denitrification rate and microbial mechanisms of two CWs with different water levels in response to decreasing temperatures in winter. Our study sites were located at Beijing Wildlife Rescue and Rehabilitation Center, the low surface water level site (LCW, 0-10 cm) and Cuihu Wetland Park, the high surface water level site (HCW, 40-50 cm). Denitrifying enzyme activity (DEA) and functional microbial diversity were significantly reduced at LCW, but at HCW, the decreases were not as significant as that in LCW due to the insulating effect of ice. There was no significant difference in the composition of functional microbial communities in the rhizosphere of plants from these sites. We observed changes further in the co-occurrence networks of denitrifiers with decreasing temperature. With increasing cold stress, the co-presence links between the same nir gene (nirS-nirS or nirK-nirK) and the mutual exclusion nirS-nirK links gradually increased, indicating that similar denitrifiers tend to accumulate in response to cold stress. In addition, Bradyrhizobium (nirS/nirK), Azoarcus (nirS), Azospira (nirS), Pseudomonads (nirS) and Rhizobium (nirK) as the keystone species are the primary contributors to the denitrification process in winter. Overall, denitrification was stronger in CWs with high water levels (HCW, 40-50 cm) during the freezing period in winter, and the more similar nirK- or nirS- denitrifiers collaborated to maintain denitrification under cold stress.