Institution: | 1.State Key Lab of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing,People’s Republic of China;2.University of Chinese Academy of Sciences,Beijing,People’s Republic of China;3.State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment,Tsinghua University,Beijing,People’s Republic of China;4.Institute of Agricultural Resources and Environments,Jiangsu Academy of Agricultural Sciences,Nanjing,People’s Republic of China;5.Key Lab of Urban Environment and Health, Institute of Urban Environment,Chinese Academy of Sciences,Xiamen,People’s Republic of China;6.Zoology Department, College of Science,King Saud University,Dariyah,Saudi Arabia |
Abstract: | PurposeExoelectrogens are important microorganisms playing crucial roles in the biogeochemistry of elements in paddy soils. But it remains unclear how the soil properties and geographical distances affect the exoelectrogen communities of Chinese paddy soils. So the objectives of this study were to investigate the diversity and composition of these microbial communities which were enriched on the anodes of soil microbial fuel cells (SMFCs) and to elucidate the links between the microbial community compositions and their driving factors.Materials and methodsWe used Illumina HiSeq sequencing to determine the bacterial community structures which were enriched on the anodes of SMFCs. Variance partitioning analysis (VPA) was used to obtain the contribution of soil properties and geographical distance to the variations of bacterial communities.Results and discussionActive bacterial community on anodes of the closed circuit SMFCs differs significantly from the control open circuit SMFCs. Anodes of all the closed circuit SMFCs were characterized by the presence of high numbers of Nitrospira and Anaerolineae. Taxonomic similarities and phylogenetic similarities of bacterial communities from different paddy soil samples across North and South China were found to be significantly correlated with geographical distances. The relationship between the similarities and the geographic distance exhibited a distance-decay relationship. VPA showed that both geographical distances and soil properties affect the structure of bacterial communities detected on anodes.ConclusionsOur study gives a foundation for understanding the distribution and diversity of exoelectrogens in paddy soils and elucidates the links between the distribution and the diversity of extracellular respiring bacteria and their driving factors. Furthermore, this study also identifies the crucial factors which should be used to evaluate the response of exoelectrogens to environmental perturbations in Chinese paddy soils. |