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Title: Rare Taxa Maintain Microbial Diversity and Contribute to Terrestrial Community Dynamics throughout Bark Beetle Infestation

Journal Article · · Applied and Environmental Microbiology
DOI:https://doi.org/10.1128/AEM.02245-16· OSTI ID:1465356
 [1];  [1];  [2]
  1. Colorado School of Mines, Golden, CO (United States). Dept. of Civil and Environmental Engineering
  2. Colorado School of Mines, Golden, CO (United States). Dept. of Civil and Environmental Engineering; Colorado School of Mines, Golden, CO (United States). Hydrologic Science and Engineering Program

A global phenomenon of increasing bark beetle-induced tree mortality has heightened concerns regarding ecosystem response and biogeochemical implications. Here, we explore microbial dynamics under lodgepole pines through the analysis of bulk (16S rRNA gene) and potentially active (16S rRNA) communities to understand the terrestrial ecosystem responses that are associated with this form of large-scale tree mortality. Here, we found that the relative abundances of bulk and potentially active taxa were correlated across taxonomic levels, but at lower levels, cladal differences became more apparent. Despite this correlation, there was a strong differentiation of community composition between bulk and potentially active taxa, with further clustering associated with the stages of tree mortality. Surprisingly, community clustering as a function of tree phase had limited correlation to soil water content and total nitrogen concentrations, which were the only two measured edaphic parameters to differ in association with tree phase. Bacterial clustering is more readily explained by the observed decrease in the abundance of active, rare microorganisms after tree death in conjunction with stable alpha diversity measurements. This enables the rare fraction of the terrestrial microbial community to maintain metabolic diversity by transitioning between metabolically active and dormant states during this ecosystem disturbance and contributes disproportionately to community dynamics and archived metabolic capabilities. Here, these results suggest that analyzing bulk and potentially active communities after beetle infestation may be a more sensitive indicator of disruption than measuring local edaphic parameters. Forests around the world are experiencing unprecedented mortality due to insect infestations that are fueled in part by a changing climate. While aboveground processes have been explored, changes at the terrestrial interface that are relevant to microbial biogeochemical cycling remain largely unknown. Here in this study, we investigated the changing bulk and potentially active microbial communities beneath healthy and beetle-killed trees. We found that, even though few edaphic parameters were altered from beetle infestation, the rare microbes were more likely to be active and fluctuate between dormancy and metabolic activity. Finally, this indicates that rare as opposed to abundant taxa contribute disproportionately to microbial community dynamics and presumably biogeochemical cycling within these types of perturbed ecosystems.

Research Organization:
Colorado School of Mines, Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Biological and Environmental Research (BER); National Science Foundation (NSF)
Grant/Contract Number:
SC0016451
OSTI ID:
1465356
Journal Information:
Applied and Environmental Microbiology, Vol. 82, Issue 23; ISSN 0099-2240
Publisher:
American Society for MicrobiologyCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 11 works
Citation information provided by
Web of Science

References (35)

When the forest dies: the response of forest soil fungi to a bark beetle-induced tree dieback journal March 2014
Rhizosphere carbon flow in trees, in comparison with annual plants: the importance of root exudation and its impact on microbial activity and nutrient availability journal January 1997
Carbon and nitrogen cycling immediately following bark beetle outbreaks in southwestern ponderosa pine forests journal April 2008
Surface temperature change of spruce forest as a result of bark beetle attack: remote sensing and GIS approach journal April 2008
Effect of gap size on litter decomposition and soil nitrate concentrations in a high-elevation spruce–fir forest journal November 2003
Different bulk and active bacterial communities in cryoconite from the margin and interior of the Greenland ice sheet: Bulk and active bacteria in Greenland cryoconite journal January 2015
Greengenes, a Chimera-Checked 16S rRNA Gene Database and Workbench Compatible with ARB journal July 2006
Temperature as a potent driver of regional forest drought stress and tree mortality journal September 2012
Root Gap Dynamics in Lodgepole Pine Forest: Nitrogen Transformations in Gaps of Different Size journal May 1994
Comparison of Diversities and Compositions of Bacterial Populations Inhabiting Natural Forest Soils journal September 2004
Responses of soil and water chemistry to mountain pine beetle induced tree mortality in Grand County, Colorado, USA journal June 2011
The influence of soil properties on the structure of bacterial and fungal communities across land-use types journal September 2008
Rare but active taxa contribute to community dynamics of benthic biofilms in glacier-fed streams: Benthic biofilms in glacier-fed streams journal February 2014
Bark beetle infestation impacts on nutrient cycling, water quality and interdependent hydrological effects journal June 2013
Development of a Dual-Index Sequencing Strategy and Curation Pipeline for Analyzing Amplicon Sequence Data on the MiSeq Illumina Sequencing Platform journal June 2013
Ecohydrological consequences of drought- and infestation- triggered tree die-off: insights and hypotheses journal August 2011
Quantitative and Qualitative   Diversity Measures Lead to Different Insights into Factors That Structure Microbial Communities journal January 2007
Mountain pine beetle infestation impacts: modeling water and energy budgets at the hill-slope scale: PINE BEETLE IMPACTS ON THE WATER AND ENERGY BUDGET journal December 2011
Biogeography and habitat modelling of high-alpine bacteria journal August 2010
Evaluating rRNA as an indicator of microbial activity in environmental communities: limitations and uses journal July 2013
Active and total microbial communities in forest soil are largely different and highly stratified during decomposition journal July 2011
Differential abundance analysis for microbial marker-gene surveys journal September 2013
Response of soil chemistry to forest dieback after bark beetle infestation journal July 2012
Waste Not, Want Not: Why Rarefying Microbiome Data Is Inadmissible journal April 2014
Microbial seed banks: the ecological and evolutionary implications of dormancy journal January 2011
Activity of abundant and rare bacteria in a coastal ocean journal July 2011
Altered edaphic parameters couple to shifts in terrestrial bacterial community structure associated with insect-induced tree mortality journal April 2016
Resistance, resilience, and redundancy in microbial communities journal August 2008
UniFrac: an effective distance metric for microbial community comparison journal September 2010
Seasonal Changes in an Alpine Soil Bacterial Community in the Colorado Rocky Mountains journal May 2004
Rapid soil organic matter loss from forest dieback in a subalpine coniferous ecosystem journal December 2011
Search and clustering orders of magnitude faster than BLAST journal August 2010
phyloseq: An R Package for Reproducible Interactive Analysis and Graphics of Microbiome Census Data journal April 2013
Soil bacterial community structure remains stable over a 5-year chronosequence of insect-induced tree mortality journal December 2014
Distinct summer and winter bacterial communities in the active layer of Svalbard permafrost revealed by DNA- and RNA-based analyses journal April 2015

Cited By (2)

Rare Taxa Exhibit Disproportionate Cell-Level Metabolic Activity in Enriched Anaerobic Digestion Microbial Communities journal January 2019
Vertical vs. horizontal transmission of the microbiome in a key disease vector, Ixodes pacificus journal November 2017