Climate warming is likely to increase the frequency and severity of forest disturbances, with uncertain consequences for soil microbial communities and their contribution to ecosystem C dynamics. To address this uncertainty, we conducted a meta-analysis of 139 published soil microbial responses to forest disturbances. These disturbances included abiotic (fire, harvesting, storm) and biotic (insect, pathogen) disturbances. We hypothesized that soil microbial biomass would decline following forest disturbances, but that abiotic disturbances would elicit greater reductions in microbial biomass than biotic disturbances. In support of this hypothesis, across all published studies, disturbances reduced soil microbial biomass by an average of 29.4%. However, microbial responses differed between abiotic and biotic disturbances. Microbial responses were significantly negative following fires, harvest, and storms (48.7, 19.1, and 41.7% reductions in microbial biomass, respectively). In contrast, changes in soil microbial biomass following insect infestation and pathogen-induced tree mortality were non-significant, although biotic disturbances were poorly represented in the literature. When measured separately, fungal and bacterial responses to disturbances mirrored the response of the microbial community as a whole. Changes in microbial abundance following disturbance were significantly positively correlated with changes in microbial respiration. We propose that the differential effect of abiotic and biotic disturbances on microbial biomass may be attributable to differences in soil disruption and organic C removal from forests among disturbance types. Altogether, these results suggest that abiotic forest disturbances may significantly decrease soil microbial abundance, with corresponding consequences for microbial respiration. Further studies are needed on the effect of biotic disturbances on forest soil microbial communities and soil C dynamics.
A meta-analysis of soil microbial biomass responses to forest disturbances
Published 2013 in Frontiers in Microbiology
ABSTRACT
PUBLICATION RECORD
- Publication year
2013
- Venue
Frontiers in Microbiology
- Publication date
2013-06-20
- Fields of study
Biology, Medicine, Environmental Science
- Identifiers
- External record
- Source metadata
Semantic Scholar, PubMed
CITATION MAP
EXTRACTION MAP
CLAIMS
CONCEPTS
- abiotic disturbances
Non-living disturbance agents in forests, including fire, harvesting, and storms in this synthesis.
- biotic disturbances
Disturbance agents caused by living organisms, such as insects and pathogens, considered separately from abiotic events.
- fire
A combustion-driven forest disturbance that can alter vegetation and soil conditions.
- forest disturbances
Events that alter forest structure or resources and trigger the microbial responses synthesized in the meta-analysis.
- harvesting
Forest tree removal through logging or related management operations.
- microbial respiration
The carbon dioxide flux generated by soil microbial metabolism, used as a linked ecosystem process.
- soil microbial biomass
The amount of microbial living mass present in forest soil, used here as the main response variable.
- storm
A weather-driven forest disturbance that can damage trees and soil structure.