The diversity and co-occurrence patterns of N2-fixing communities in a CO2-enriched grassland ecosystem

Loading...
Thumbnail Image

View/Download File

Persistent link to this item

Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

The diversity and co-occurrence patterns of N2-fixing communities in a CO2-enriched grassland ecosystem

Published Date

2016

Publisher

springer

Type

Article

Abstract

Diazotrophs are the major organismal group responsible for atmospheric nitrogen (N2) fixation in natural ecosystems. The extensive diversity and structure of N2-fixing communities in grassland ecosystems and their responses to increasing atmospheric CO2 remain to be further explored. Through pyrosequencing of nifH gene amplicons and extraction of nifH genes from shotgun metagenomes, coupled with co-occurrence ecological network analysis approaches, we comprehensively analyzed the diazotrophic community in a grassland ecosystem exposed to elevated CO2 (eCO2) for 12 years. Long-term eCO2 increased the abundance of nifH genes but did not change the overall nifH diversity and diazotrophic community structure. Taxonomic and phylogenetic analysis of amplified nifH sequences suggested a high diversity of nifH genes in the soil ecosystem, the majority belonging to nifH clusters I and II. Co-occurrence ecological network analysis identified different co-occurrence patterns for different groups of diazotrophs, such as Azospirillum/Actinobacteria, Mesorhizobium/Conexibacter, and Bradyrhizobium/Acidobacteria. This indicated a potential attraction of non-N2-fixers by diazotrophs in the soil ecosystem. Interestingly, more complex co-occurrence patterns were found for free-living diazotrophs than commonly known symbiotic diazotrophs, which is consistent with the physical isolation nature of symbiotic diazotrophs from the environment by root nodules. The study provides novel insights into our understanding of the microbial ecology of soil diazotrophs in natural ecosystems.

Description

Related to

Replaces

License

Collections

Series/Report Number

Funding information

Isbn identifier

Doi identifier

10.1007/s00248-015-0659-7

Previously Published Citation

Tu, Q., Zhou, X., He, Z. et al. Microb Ecol (2016) 71: 604. doi:10.1007/s00248-015-0659-7

Suggested citation

Tu, Qichao; Zhou, Xishu; He, Zhili; Xue, Kai; Wu, Liyou; Reich, Peter B; Hobbie, Sarah; Zhou, Jizhong. (2016). The diversity and co-occurrence patterns of N2-fixing communities in a CO2-enriched grassland ecosystem. Retrieved from the University Digital Conservancy, 10.1007/s00248-015-0659-7.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.