Microbes catalyze all major geochemical cycles on earth. However, the role of microbial traits and community composition in biogeochemical cycles is still poorly understood mainly due to the inability to assess the community members that are actually performing biogeochemical conversions in complex environmental samples. Here we applied a polyphasic approach to assess the role of microbial community composition in modulating methane emission from a riparian floodplain. We show that the dynamics and intensity of methane consumption in riparian wetlands coincide with relative abundance and activity of specific subgroups of methane-oxidizing bacteria (MOB), which can be considered as a minor component of the microbial community in this ecosystem. Microarray-based community composition analyses demonstrated linear relationships of MOB diversity parameters and in vitro methane consumption. Incubations using intact cores in combination with stable isotope labeling of lipids and proteins corroborated the correlative evidence from in vitro incubations demonstrating γ-proteobacterial MOB subgroups to be responsible for methane oxidation. The results obtained within the riparian flooding gradient collectively demonstrate that niche partitioning of MOB within a community comprised of a very limited amount of active species modulates methane consumption and emission from this wetland. The implications of the results obtained for biodiversity-ecosystem functioning are discussed with special reference to the role of spatial and temporal heterogeneity and functional redundancy.

Item Type:	Refereed Article
Keywords:	biodiversity-ecosystem functioning, methane oxidation, stable isotope labeling, proteomics, wetlands
Research Division:	Environmental Sciences
Research Group:	Ecological applications
Research Field:	Ecosystem function
Objective Division:	Environmental Management
Objective Group:	Marine systems and management
Objective Field:	Assessment and management of benthic marine ecosystems
UTAS Author:	Bodrossy, L (Dr Levente Bodrossy)
ID Code:	116629
Year Published:	2013
Web of Science® Times Cited:	71
Deposited By:	Tasmanian Institute of Agriculture
Deposited On:	2017-05-15
Last Modified:	2017-10-20
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