Experimental assessment of tree canopy and leaf litter controls on the microbiome and nitrogen fixation rates of two boreal mosses
- 16 April 2020
- journal article
- research article
- Published by Wiley in New Phytologist
- Vol. 227 (5), 1335-1349
- https://doi.org/10.1111/nph.16611
Abstract
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 Hylocomium splendens and Pleurozium schreberi. We conducted a moss transplant and leaf litter manipulation experiment at three sites with paired paper birch (Betula neoalaskana) and black spruce (Picea mariana) stands in Alaska. We characterized bacterial communities using marker gene sequencing, determined N2-fixation rates using stable isotopes (15N2) and measured environmental covariates. 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 H. splendens, which had the highest rates. N2-fixation was positively associated with several bacterial taxa, including cyanobacteria. 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.Keywords
Funding Information
- Division of Environmental Biology (0620579, 1542586)
- U.S. Forest Service (PNW01‐JV11261952‐23)
- Natural Sciences and Engineering Research Council of Canada
- U.S. Department of Defense (RC‐2109)
This publication has 60 references indexed in Scilit:
- Boreal feather mosses secrete chemical signals to gain nitrogenNew Phytologist, 2013
- Ultra-high-throughput microbial community analysis on the Illumina HiSeq and MiSeq platformsThe ISME Journal, 2012
- Search and clustering orders of magnitude faster than BLASTBioinformatics, 2010
- Generalized linear mixed models: a practical guide for ecology and evolutionTrends in Ecology & Evolution, 2009
- Ecosystem Feedbacks and Nitrogen Fixation in Boreal ForestsScience, 2008
- Ecosystem controls on nitrogen fixation in boreal feather moss communitiesOecologia, 2007
- Analysis of vegetation distribution in Interior Alaska and sensitivity to climate change using a logistic regression approachJournal of Biogeography, 2005
- Estimating N2fixation in two species ofAlnusin interior Alaska using acetylene reduction and15N2uptakeÉcoscience, 2004
- Quantifying nitrogen-fixation in feather moss carpets of boreal forestsNature, 2002
- Site-to-site variations in nitrogenase activity in a subarctic black spruce forestCanadian Journal of Forest Research, 1983