Wildfire overrides hydrological controls on boreal peatland methane emissions
Boreal peatlands represent a globally important store of carbon, and disturbances such as wildfire can have a negative feedback to the climate. Understanding how carbon exchange and greenhouse gas (GHG) dynamics are impacted after a wildfire is important, especially as boreal peatlands may be vulner...
Published in: | Biogeosciences |
---|---|
Main Authors: | , , , |
Format: | Text |
Language: | English |
Published: |
2019
|
Subjects: | |
Online Access: | https://doi.org/10.5194/bg-16-2651-2019 https://www.biogeosciences.net/16/2651/2019/ |
id |
ftcopernicus:oai:publications.copernicus.org:bg75778 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:bg75778 2023-05-15T16:17:41+02:00 Wildfire overrides hydrological controls on boreal peatland methane emissions Davidson, Scott J. Beest, Christine Petrone, Richard Strack, Maria 2019-07-09 application/pdf https://doi.org/10.5194/bg-16-2651-2019 https://www.biogeosciences.net/16/2651/2019/ eng eng doi:10.5194/bg-16-2651-2019 https://www.biogeosciences.net/16/2651/2019/ eISSN: 1726-4189 Text 2019 ftcopernicus https://doi.org/10.5194/bg-16-2651-2019 2019-12-24T09:48:59Z Boreal peatlands represent a globally important store of carbon, and disturbances such as wildfire can have a negative feedback to the climate. Understanding how carbon exchange and greenhouse gas (GHG) dynamics are impacted after a wildfire is important, especially as boreal peatlands may be vulnerable to changes in wildfire regime under a rapidly changing climate. However, given this vulnerability, there is very little in the literature on the impact such fires have on methane ( CH 4 ) emissions. This study investigated the effect of wildfire on CH 4 emissions at a boreal fen near Fort McMurray, Alberta, Canada, that was partially burned by the Horse River Wildfire in 2016. We measured CH 4 emissions and environmental variables (2017–2018) and CH 4 production potential (2018) in two different microform types (hummocks and hollows) across a peat burn severity gradient (unburned (UB), moderately burned (MB), and severely burned (SB)). Results indicated a switch in the typical understanding of boreal peatland CH 4 emissions. For example, emissions were significantly lower in the MB and SB hollows in both years compared to UB hollows. Interestingly, across the burned sites, hummocks had higher fluxes in 2017 than hollows at the MB and SB sites. We found typically higher emissions at the UB site where the water table was close to the surface. However, at the burned sites, no relationship was found between CH 4 emissions and water table, even under similar hydrological conditions. There was also significantly higher CH 4 production potential from the UB site than the burned sites. The reduction in CH 4 emissions and production in the hollows at burned sites highlights the sensitivity of hollows to fire, removing labile organic material for potential methanogenesis. The previously demonstrated resistance of hummocks to fire also results in limited impact on CH 4 emissions and likely faster recovery to pre-fire rates. Given the potential initial net cooling effect resulting from a reduction in CH 4 emissions, it is important that the radiative effect of all GHGs following wildfire across peatlands is taken into account. Text Fort McMurray Copernicus Publications: E-Journals Canada Fort McMurray Horse River ENVELOPE(-111.385,-111.385,56.717,56.717) Biogeosciences 16 13 2651 2660 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Boreal peatlands represent a globally important store of carbon, and disturbances such as wildfire can have a negative feedback to the climate. Understanding how carbon exchange and greenhouse gas (GHG) dynamics are impacted after a wildfire is important, especially as boreal peatlands may be vulnerable to changes in wildfire regime under a rapidly changing climate. However, given this vulnerability, there is very little in the literature on the impact such fires have on methane ( CH 4 ) emissions. This study investigated the effect of wildfire on CH 4 emissions at a boreal fen near Fort McMurray, Alberta, Canada, that was partially burned by the Horse River Wildfire in 2016. We measured CH 4 emissions and environmental variables (2017–2018) and CH 4 production potential (2018) in two different microform types (hummocks and hollows) across a peat burn severity gradient (unburned (UB), moderately burned (MB), and severely burned (SB)). Results indicated a switch in the typical understanding of boreal peatland CH 4 emissions. For example, emissions were significantly lower in the MB and SB hollows in both years compared to UB hollows. Interestingly, across the burned sites, hummocks had higher fluxes in 2017 than hollows at the MB and SB sites. We found typically higher emissions at the UB site where the water table was close to the surface. However, at the burned sites, no relationship was found between CH 4 emissions and water table, even under similar hydrological conditions. There was also significantly higher CH 4 production potential from the UB site than the burned sites. The reduction in CH 4 emissions and production in the hollows at burned sites highlights the sensitivity of hollows to fire, removing labile organic material for potential methanogenesis. The previously demonstrated resistance of hummocks to fire also results in limited impact on CH 4 emissions and likely faster recovery to pre-fire rates. Given the potential initial net cooling effect resulting from a reduction in CH 4 emissions, it is important that the radiative effect of all GHGs following wildfire across peatlands is taken into account. |
format |
Text |
author |
Davidson, Scott J. Beest, Christine Petrone, Richard Strack, Maria |
spellingShingle |
Davidson, Scott J. Beest, Christine Petrone, Richard Strack, Maria Wildfire overrides hydrological controls on boreal peatland methane emissions |
author_facet |
Davidson, Scott J. Beest, Christine Petrone, Richard Strack, Maria |
author_sort |
Davidson, Scott J. |
title |
Wildfire overrides hydrological controls on boreal peatland methane emissions |
title_short |
Wildfire overrides hydrological controls on boreal peatland methane emissions |
title_full |
Wildfire overrides hydrological controls on boreal peatland methane emissions |
title_fullStr |
Wildfire overrides hydrological controls on boreal peatland methane emissions |
title_full_unstemmed |
Wildfire overrides hydrological controls on boreal peatland methane emissions |
title_sort |
wildfire overrides hydrological controls on boreal peatland methane emissions |
publishDate |
2019 |
url |
https://doi.org/10.5194/bg-16-2651-2019 https://www.biogeosciences.net/16/2651/2019/ |
long_lat |
ENVELOPE(-111.385,-111.385,56.717,56.717) |
geographic |
Canada Fort McMurray Horse River |
geographic_facet |
Canada Fort McMurray Horse River |
genre |
Fort McMurray |
genre_facet |
Fort McMurray |
op_source |
eISSN: 1726-4189 |
op_relation |
doi:10.5194/bg-16-2651-2019 https://www.biogeosciences.net/16/2651/2019/ |
op_doi |
https://doi.org/10.5194/bg-16-2651-2019 |
container_title |
Biogeosciences |
container_volume |
16 |
container_issue |
13 |
container_start_page |
2651 |
op_container_end_page |
2660 |
_version_ |
1766003578517848064 |