Original Research ARTICLE
Diversity, Distribution and Co-occurrence Patterns of Bacterial Communities in a Karst Cave System
- 1State Key Laboratory of Microbial Resources, Institute of Microbiology (CAS), China
- 2University of Chinese Academy of Sciences, China
- 3Other, China
- 4State Key Laboratory of Mycology, Institute of Microbiology (CAS), China
Caves are typified by their permanent darkness and a shortage of nutrients. Consequently, bacteria play an important role in sustaining such subsurface ecosystems by dominating primary production and fueling biogeochemical cycles. China has one of the world’s largest areas of karst topography in the Yunnan-Guizhou Plateau, yet the bacteriomes in these karst caves remain unexplored. In this study, bacteriomes of eight karst caves in southwest China were examined, and co-occurrence networks of cave bacterial communities were constructed. Results revealed abundant and diversified bacterial communities in karst caves, with Proteobacteria, Actinobacteria, and Firmicutes being the most abundant phyla. Statistical analysis revealed no significant difference in bacteriomes among the eight caves. However, a PCoA plot did show that the bacterial communities of 128 cave samples clustered into groups corresponding to sampling types (air, water, rock, and sediment). These results suggested that the distribution of bacterial communities was driven more by sample types than the separate caves from which samples were collected. Further community-level composition analysis indicated that Proteobacteria were most dominant in water and air samples, while Actinobacteria dominated the sediment and rock samples. Co-occurrence analysis revealed highly modularized assembly patterns of the cave bacterial community, with Nitrosococcaceae wb1-P19, an uncultured group in Rokubacteriales, and an uncultured group in Gaiellales, being the top-three keystone members. These results not only expand our understanding of cave bacteriomes but also inspired functional exploration of bacterial strains in karst caves.
Keywords: Karst cave, Bacteriomes, Community composition and abundance, Co-occurrence pattern, Bacterial diveristy
Received: 17 Mar 2019;
Accepted: 12 Jul 2019.
Edited by:Bradley M. Tebo, Oregon Health & Science University, United States
Reviewed by:Suzanna Bräuer, Appalachian State University, United States
Diana E. Northup, University of New Mexico, United States
Copyright: © 2019 Liu, Zhu, Zhang, Zhou, Jiang, Wang and Cai. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Shuang-Jiang Liu, State Key Laboratory of Microbial Resources, Institute of Microbiology (CAS), Beijing, China, firstname.lastname@example.org