Abstract
The climate sensitivity of microbe-mediated soil processes such as carbon and nitrogen cycling offers an interesting case for evaluating the corresponding sensitivity of microbial community composition to environmental change. Better understanding of the degree of linkage between functional and compositional stability would contribute to ongoing efforts to build mechanistic models aiming at predicting rates of microbe-mediated processes. We used an amplicon sequencing approach to test if previously observed large effects of experimental soil warming on C and N cycle fluxes (50-100% increases) in a sub-arctic Sphagnum peatland were reflected in changes in the composition of the soil bacterial community. We found that treatments that previously induced changes to fluxes did not associate with changes in the phylogenetic composition of the soil bacterial community. For both DNA- and RNA-based analyses, variation in bacterial communities could be explained by the hierarchy: spatial variation (12-15% of variance explained) > temporal variation (7-11%) > climate treatment (4-9%). We conclude that the bacterial community in this environment is stable under changing conditions, despite the previously observed sensitivity of process rates-evidence that microbe-mediated soil processes can alter without concomitant changes in bacterial communities. We propose that progress in linking soil microbial communities to ecosystem processes can be advanced by further investigating the relative importance of community composition effects versus physico-chemical factors in controlling biogeochemical process rates in different contexts.
Original language | English |
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Article number | 317 |
Journal | Frontiers in Microbiology |
Volume | 8 |
Issue number | MAR |
DOIs | |
Publication status | Published - 2017 |
Funding
Computing resources were provided by the SARA/BigGrid computing facility. This study was financially supported by the Netherlands Organisation for Scientific Research (NWO) by NWO-ALW grant 816.01.012 to RA and GK. We gratefully acknowledge the efforts of Hans Cornelissen, Richard van Logtestijn, and Ellen Dorrepaal in establishing and maintaining the OTC experiment. We thank Daoud Sie and Paul Eijk at the VUMC Microarray Facility for sequencing services, Jan Karlsson for use of lab space and equipment at Abisko, the staff of Abisko Scientific Research Station for hosting us during fieldwork, and Sarah Jennings and Julia Huet for testing and optimizing PCR protocols and helpful discussions on data analysis. We dedicate this article to the memory of our dear friend and colleague WR, who passed away during the final stages of manuscript preparation
Funders | Funder number |
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NWO-ALW | 816.01.012 |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek |
Keywords
- peatlands, bacteria, climate change, soil organic carbon, soil nitrogen, seasonality, 16S RNA, 16S DNA