The Synergism between Methanogens and Methanotrophs and the Nature of their Contributions to the Seasonal Variation of Methane Fluxes in a Wetland:The Case of Dajiuhu Subalpine Peatland  

作　　者：Luwen WANG Jiwen GE Liang FENG Yaoyao LIU Yu LI Jiumei WANG Xiang XIAO Zhiqi ZHANG 

机构地区：[1]Laboratory of Basin Hydrology and Wetland Eco-Restoration,China University of Geosciences,Wuhan 430074,China [2]Hubei Key Laboratory of Wetland Evolution and Ecological Restoration,China University of Geosciences,Wuhan 430074,China [3]Institution of Ecology and Environmental Sciences,China University of Geosciences,Wuhan 430074,China [4]Shennongjia National Park Administration Bureau,Shennongjia Forestry District 442417,China

出　　处：《Advances in Atmospheric Sciences》2022年第8期1375-1385,I0017-I0023,共18页大气科学进展（英文版）

基　　金：supported by the National Science Foundation of China(Grant No.31971490).

摘　　要：Wetland ecosystems are the most important natural methane(CH_(4))sources,whose fluxes periodically fluctuate.Methanogens(methane producers)and methanotrophs(methane consumers)are considered key factors affecting CH_(4)fluxes in wetlands.However,the symbiotic relationship between methanogens and methanotrophs remains unclear.To help close this research gap,we collected and analyzed samples from four soil depths in the Dajiuhu subalpine peatland in January,April,July,and October 2019 and acquired seasonal methane flux data from an eddy covariance(EC)system,and investigated relationships.A phylogenetic molecular ecological networks(pMENs)analysis was used to identify keystone species and the seasonal variations of the co-occurrence patterns of methanogenic and methanotrophic communities.The results indicate that the seasonal variations of the interactions between methanogenic and methanotrophic communities contributed to CH_(4)emissions in wetlands.The keystone species discerned by the network analysis also showed their importance in mediating CH_(4)fluxes.Methane(CH_(4))emissions in wetlands were lowest in spring;during this period,the most complex interactions between microbes were observed,with intense competition among methanogens while methanotrophs demonstrated better cooperation.Reverse patterns manifested themselves in summer when the highest CH_(4)flux was observed.Methanoregula formicica was negatively correlated with CH_(4)fluxes and occupied the largest ecological niches in the spring network.In contrast,both Methanocella arvoryzae and Methylocystaceae demonstrated positive correlations with CH_(4)fluxes and were better adapted to the microbial community in the summer.In addition,soil temperature and nitrogen were regarded as significant environmental factors to CH_(4)fluxes.This study was successful in explaining the seasonal patterns and microbial driving mechanisms of CH_(4)emissions in wetlands.

关 键 词：CH_(4)fluxes WETLAND METHANOGENS METHANOTROPHS molecular ecological network 

分 类 号：X171.1[环境科学与工程—环境科学] X16