Soil Microbial Community Responses to Multiple Experimental Climate Change Drivers

Journal Article · Fri Jan 01 04:00:00 EST 2010 · Applied and Environmental Microbiology

DOI:https://doi.org/10.1128/AEM.02874-09· OSTI ID:973545

Castro Gonzalez, Hector F ^[1]; Classen, Aimee T ^[1]; Austin, Emily E ^[1]; Norby, Richard J ^[1]; Schadt, Christopher Warren ^[1]

---

1. ORNL

Researchers agree that climate change factors such as rising atmospheric [CO{sub 2}] and warming will likely interact to modify ecosystem properties and processes. However, the response of the microbial communities that regulate ecosystem processes is less predictable. We measured the direct and interactive effects of climatic change on soil fungal and bacterial communities (abundance and composition) in a multifactor climate change experiment that exposed a constructed old-field ecosystem to different atmospheric CO{sub 2} concentration (ambient, +300 ppm), temperature (ambient, +3 C), and precipitation (wet and dry) might interact to alter soil bacterial and fungal abundance and community structure in an old-field ecosystem. We found that (i) fungal abundance increased in warmed treatments; (ii) bacterial abundance increased in warmed plots with elevated atmospheric [CO{sub 2}] but decreased in warmed plots under ambient atmospheric [CO{sub 2}]; (iii) the phylogenetic distribution of bacterial and fungal clones and their relative abundance varied among treatments, as indicated by changes in 16S rRNA and 28S rRNA genes; (iv) changes in precipitation altered the relative abundance of Proteobacteria and Acidobacteria, where Acidobacteria decreased with a concomitant increase in the Proteobacteria in wet relative to dry treatments; and (v) changes in precipitation altered fungal community composition, primarily through lineage specific changes within a recently discovered group known as soil clone group I. Taken together, our results indicate that climate change drivers and their interactions may cause changes in bacterial and fungal overall abundance; however, changes in precipitation tended to have a much greater effect on the community composition. These results illustrate the potential for complex community changes in terrestrial ecosystems under climate change scenarios that alter multiple factors simultaneously.

• Research Organization: Oak Ridge National Laboratory (ORNL); Oak Ridge National Environmental Research Park
• Sponsoring Organization: ORNL LDRD Director's R&D
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 973545
• Journal Information: Applied and Environmental Microbiology, Journal Name: Applied and Environmental Microbiology Journal Issue: 4 Vol. 76; ISSN AEMIDF; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
59 BASIC BIOLOGICAL SCIENCES
ABUNDANCE
CLIMATES
CLIMATIC CHANGE
COMMUNITIES
DISTRIBUTION
ECOSYSTEMS
GENES
PRECIPITATION
SOILS
TERRESTRIAL ECOSYSTEMS