TY - JOUR

T1 - Impact of peat mining and restoration on methane turnover potential and methane-cycling microorganisms in a northern bog

AU - Reumer, Max

AU - Harnisz, Monika

AU - Lee, Hyo Jung

AU - Reim, Andreas

AU - Grunert, Oliver

AU - Putkinen, Anuliina

AU - Fritze, Hannu

AU - Bodelier, Paul L.E.

AU - Ho, Adrian

N1 - Publisher Copyright: © 2018 American Society for Microbiology. Copyright: Copyright 2018 Elsevier B.V., All rights reserved.

PY - 2018/2/1

Y1 - 2018/2/1

N2 - Ombrotrophic peatlands are a recognized global carbon reservoir. Without restoration and peat regrowth, harvested peatlands are dramatically altered, impairing their carbon sink function, with consequences for methane turnover. Previous studies determined the impact of commercial mining on the physicochemical properties of peat and the effects on methane turnover. However, the response of the underlying microbial communities catalyzing methane production and oxidation have so far received little attention. We hypothesize that with the return of Sphagnum spp. postharvest, methane turnover potential and the corresponding microbial communities will converge in a natural and restored peatland. To address our hypothesis, we determined the potential methane production and oxidation rates in natural (as a reference), actively mined, abandoned, and restored peatlands over two consecutive years. In all sites, the methanogenic and methanotrophic population sizes were enumerated using quantitative PCR (qPCR) assays targeting the mcrA and pmoA genes, respectively. Shifts in the community composition were determined using Illumina MiSeq sequencing of the mcrA gene and a pmoA-based terminal restriction fragment length polymorphism (t-RFLP) analysis, complemented by cloning and sequence analysis of the mmoX gene. Peat mining adversely affected methane turnover potential, but the rates recovered in the restored site. The recovery in potential activity was reflected in the methanogenic and methanotrophic abundances. However, the microbial community composition was altered, being more pronounced for the methanotrophs. Overall, we observed a lag between the recovery of the methanogenic/ methanotrophic activity and the return of the corresponding microbial communities, suggesting that a longer duration (> 15 years) is needed to reverse mining-induced effects on the methane-cycling microbial communities.

AB - Ombrotrophic peatlands are a recognized global carbon reservoir. Without restoration and peat regrowth, harvested peatlands are dramatically altered, impairing their carbon sink function, with consequences for methane turnover. Previous studies determined the impact of commercial mining on the physicochemical properties of peat and the effects on methane turnover. However, the response of the underlying microbial communities catalyzing methane production and oxidation have so far received little attention. We hypothesize that with the return of Sphagnum spp. postharvest, methane turnover potential and the corresponding microbial communities will converge in a natural and restored peatland. To address our hypothesis, we determined the potential methane production and oxidation rates in natural (as a reference), actively mined, abandoned, and restored peatlands over two consecutive years. In all sites, the methanogenic and methanotrophic population sizes were enumerated using quantitative PCR (qPCR) assays targeting the mcrA and pmoA genes, respectively. Shifts in the community composition were determined using Illumina MiSeq sequencing of the mcrA gene and a pmoA-based terminal restriction fragment length polymorphism (t-RFLP) analysis, complemented by cloning and sequence analysis of the mmoX gene. Peat mining adversely affected methane turnover potential, but the rates recovered in the restored site. The recovery in potential activity was reflected in the methanogenic and methanotrophic abundances. However, the microbial community composition was altered, being more pronounced for the methanotrophs. Overall, we observed a lag between the recovery of the methanogenic/ methanotrophic activity and the return of the corresponding microbial communities, suggesting that a longer duration (> 15 years) is needed to reverse mining-induced effects on the methane-cycling microbial communities.

KW - Land use change

KW - Methane oxidation

KW - Methanogenesis

KW - NifH

KW - Nitrogen fixation

KW - Sphagnum

UR - http://www.scopus.com/inward/record.url?scp=85040666032&partnerID=8YFLogxK

U2 - 10.1128/AEM.02218-17

DO - 10.1128/AEM.02218-17

M3 - Article

C2 - 29180368

AN - SCOPUS:85040666032

VL - 84

JO - Applied and Environmental Microbiology

JF - Applied and Environmental Microbiology

SN - 0099-2240

IS - 3

M1 - e02218-17

ER -