skip to main content


Title: The Tale of a Neglected Energy Source: Elevated Hydrogen Exposure Affects both Microbial Diversity and Function in Soil

The enrichment of H 2-oxidizing bacteria (HOB) by H 2 generated by nitrogen-fixing nodules has been shown to have a fertilization effect on several different crops. The benefit of HOB is attributed to their production of plant growth-promoting factors, yet their interactions with other members of soil microbial communities have received little attention. In this paper, we report that the energy potential of H 2, when supplied to soil, alters ecological niche partitioning of bacteria and fungi, with multifaceted consequences for both generalist and specialist microbial functions. We used dynamic microcosms to expose soil to the typical atmospheric H 2 mixing ratio (0.5 ppmv) permeating soils, as well as mixing ratios comparable to those found at the soil-nodule interface (10,000 ppmv). Elevated H 2 exposure exerted direct effects on two HOB subpopulations distinguished by their affinity for H 2 while enhancing community level carbon substrate utilization potential and lowering CH 4 uptake activity in soil. We found that H 2 triggered changes in the abundance of microorganisms that were reproducible yet inconsistent across soils at the taxonomic level and even among HOB. Overall, H 2 exposure altered microbial process rates at an intensity that depends upon soil abiotic and bioticmore » features. Finally, we argue that further examination of direct and indirect effects of H 2 on soil microbial communities will lead to a better understanding of the H 2 fertilization effect and soil biogeochemical processes.« less
 [1] ;  [1] ;  [2] ;  [3] ;  [1]
  1. National Inst. of Scientific Research (INRS), Laval, QC (Canada). Inst. Armand-Frappier
  2. National Research Council Canada, Montreal, QC (Canada)
  3. USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States)
Publication Date:
Grant/Contract Number:
AC02-05CH11231; 418252-2012
Accepted Manuscript
Journal Name:
Applied and Environmental Microbiology
Additional Journal Information:
Journal Volume: 83; Journal Issue: 11; Journal ID: ISSN 0099-2240
American Society for Microbiology
Research Org:
USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States); National Inst. of Scientific Research (INRS), Laval, QC (Canada)
Sponsoring Org:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23); Natural Sciences and Engineering Research Council of Canada (NSERC) (Canada)
Country of Publication:
United States
54 ENVIRONMENTAL SCIENCES; 59 BASIC BIOLOGICAL SCIENCES; biogeochemistry; microbial ecology; soil microbiology; trace gas
OSTI Identifier: