Wildfire Driven Succession of Microbial Community and Function in Interior Alaska - Shedding Light on the Dynamic Relationship Between Microbial and Plant Communities
Abstract
The frequency and severity of wildfires are increasing in the boreal forest due to climate change and have important implications at the ecosystem and global scales. These extreme disturbance events create landscape-level conversions of coniferous to deciduous forest. Since boreal forest soils house an estimated 25% of forest vegetation carbon and 60% of forest below-ground carbon stocks, shifts in forest type and associated below-ground microbial processes have the potential to affect global carbon balances. Capitalizing on the long history of wildfires in Interior Alaska, we sampled microbial communities within the Bonanza Creek LTER regional site network, a widely distributed series of sites designed to support long-term studies of successional dynamics following fires of differing severity. We collected soil from 25 sites (10 soil cores per site) spanning three successional stages (11-14 yr, 40-60 yr, and >80 yr) post fire. Using Illumina MiSeq targeting 16S rRNA gene amplicons as well as MinION nanopore metagenomic sequencing, we compared microbial community composition and function. Using multivariate statistics such as non-metric multidimensional scaling and multi-response permutation procedure, we tested if microbial community composition changed significantly across successional stages post fire. Using co-occurrence networks, we identified particular microbial taxa that are more commonly associated with early or late successional sites, plant species, and soil moisture contents. These network analyses also allowed us to determine how microbial functions are associated with successional stage, plant community type, and soil moisture content. This study provides a better understanding into how increased fire frequency may affect the dynamic relationship between below-ground microbial and plant communities and ultimately ecosystem function in the boreal forest.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.B23H2522S
- Keywords:
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- 0414 Biogeochemical cycles;
- processes;
- and modeling;
- BIOGEOSCIENCES;
- 0428 Carbon cycling;
- BIOGEOSCIENCES;
- 0439 Ecosystems;
- structure and dynamics;
- BIOGEOSCIENCES;
- 0475 Permafrost;
- cryosphere;
- and high-latitude processes;
- BIOGEOSCIENCES