Nitrogen (N2)‐fixing moss microbial communities play key roles in nitrogen cycling of boreal forests. Forest type and leaf litter inputs regulate moss abundance, but how they control moss microbiomes and N2‐fixation remains understudied. We examined the impacts of forest type and broadleaf litter on microbial community composition and N2‐fixation rates of We conducted a moss transplant and leaf litter manipulation experiment at three sites with paired paper birch ( Mosses native to and transplanted into spruce stands supported generally higher N2‐fixation and distinct microbial communities compared to similar treatments in birch stands. High leaf litter inputs shifted microbial community composition for both moss species and reduced N2‐fixation rates for The moss microbiome and environmental conditions controlled N2‐fixation at the stand and transplant scales. Predicted shifts from spruce‐ to deciduous‐dominated stands will interact with the relative abundances of mosses supporting different microbiomes and N2‐fixation rates, which could affect stand‐level N inputs.
Microbial communities respond to changes in environmental conditions; however, how compositional shifts affect ecosystem processes is still not well-understood and it is often assumed that different microbial communities will function equally under similar environmental conditions. We evaluated this assumption of functional redundancy using biological soil crusts (BSCs) from two arid ecosystems in Mexico with contrasting climate conditions (hot and cold deserts) following an experimental approach both in the field (reciprocal transplants) and in laboratory conditions (common garden), focusing on the community’s composition and potential for nitrogen fixation. Potential of nitrogen fixation was assessed through the acetylene reduction assay. Community composition and diversity was determined with T-RFLPs of nifH gene, high throughput sequencing of 16S rRNA gene amplicons and metagenomic libraries. BSCs tended to show higher potential nitrogen fixation rates when experiencing temperatures more similar to their native environment. Moreover, changes in potential nitrogen fixation, taxonomic and functional community composition, and diversity often depended on an interactive effect of origin of the communities and the environment they experienced. We interpret our results as legacy effects that result from ecological specialization of the BSC communities to their native environment. Overall, we present evidence of nonfunctional redundancy of BSCs in terms of nitrogen fixation.
more » « less- PAR ID:
- 10396767
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- FEMS Microbiology Ecology
- Volume:
- 99
- Issue:
- 2
- ISSN:
- 1574-6941
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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