Lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season
Boreal peatlands are major sources of dissolved organic carbon (DOC) to downstream aquatic ecosystems, where it influences carbon cycling and food web structure. Wildfire and permafrost thaw alter peatland vegetation and hydrology and may affect the quantity and chemical composition of exported DOC....
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ftunivtoronto:oai:localhost:1807/100202 2023-05-15T17:54:53+02:00 Lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season Burd, Katheryn Estop-Aragonés, Cristian Tank, Suzanne E. Olefeldt, David 2020-02-12 http://hdl.handle.net/1807/100202 http://www.nrcresearchpress.com/doi/abs/10.1139/CJSS-2019-0154 unknown NRC Research Press (a division of Canadian Science Publishing) 0008 4271 http://hdl.handle.net/1807/100202 http://www.nrcresearchpress.com/doi/abs/10.1139/CJSS-2019-0154 Article Article Post-Print 2020 ftunivtoronto 2020-06-17T12:30:53Z Boreal peatlands are major sources of dissolved organic carbon (DOC) to downstream aquatic ecosystems, where it influences carbon cycling and food web structure. Wildfire and permafrost thaw alter peatland vegetation and hydrology and may affect the quantity and chemical composition of exported DOC. We studied the influence of wildfire and thaw on microbial and photochemical lability of near-surface porewater DOC, assessed through 7 d incubations. We carried out these incubations in spring, summer, and fall but only found differences in spring when DOC biodegradability (% loss during dark incubations) increased with lower DOC aromaticity and C/N ratios. During spring, the most labile DOC was found in recently formed thermokarst bogs along collapsing peat plateau edges (25% loss), which was greater than in mature sections of thermokarst bogs (3%), and peat plateaus with intact permafrost (9%). Increased DOC lability following thaw was likely linked to high DOC production and turnover associated with productive hydrophilic Sphagnum mosses and sedges, rather than thawed permafrost peat. A wildfire (3 yr prior) reduced DOC biodegradability in both peat plateaus (4%) and rapidly collapsing peat plateau edges (14%). Biodegradability of DOC in summer and fall was low across all sites; 2% and 4%, respectively. Photodegradation was shown to potentially contribute significantly to downstream DOC degradation but did not vary across peatland sites. We show that disturbances such as permafrost thaw and wildfire have the potential to affect downstream carbon cycling, particularly as the largest influences were found in spring when peatlands are well connected to downstream aquatic ecosystems. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author. Article in Journal/Newspaper Peat Peat plateau permafrost Thermokarst University of Toronto: Research Repository T-Space |
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University of Toronto: Research Repository T-Space |
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Boreal peatlands are major sources of dissolved organic carbon (DOC) to downstream aquatic ecosystems, where it influences carbon cycling and food web structure. Wildfire and permafrost thaw alter peatland vegetation and hydrology and may affect the quantity and chemical composition of exported DOC. We studied the influence of wildfire and thaw on microbial and photochemical lability of near-surface porewater DOC, assessed through 7 d incubations. We carried out these incubations in spring, summer, and fall but only found differences in spring when DOC biodegradability (% loss during dark incubations) increased with lower DOC aromaticity and C/N ratios. During spring, the most labile DOC was found in recently formed thermokarst bogs along collapsing peat plateau edges (25% loss), which was greater than in mature sections of thermokarst bogs (3%), and peat plateaus with intact permafrost (9%). Increased DOC lability following thaw was likely linked to high DOC production and turnover associated with productive hydrophilic Sphagnum mosses and sedges, rather than thawed permafrost peat. A wildfire (3 yr prior) reduced DOC biodegradability in both peat plateaus (4%) and rapidly collapsing peat plateau edges (14%). Biodegradability of DOC in summer and fall was low across all sites; 2% and 4%, respectively. Photodegradation was shown to potentially contribute significantly to downstream DOC degradation but did not vary across peatland sites. We show that disturbances such as permafrost thaw and wildfire have the potential to affect downstream carbon cycling, particularly as the largest influences were found in spring when peatlands are well connected to downstream aquatic ecosystems. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author. |
format |
Article in Journal/Newspaper |
author |
Burd, Katheryn Estop-Aragonés, Cristian Tank, Suzanne E. Olefeldt, David |
spellingShingle |
Burd, Katheryn Estop-Aragonés, Cristian Tank, Suzanne E. Olefeldt, David Lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season |
author_facet |
Burd, Katheryn Estop-Aragonés, Cristian Tank, Suzanne E. Olefeldt, David |
author_sort |
Burd, Katheryn |
title |
Lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season |
title_short |
Lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season |
title_full |
Lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season |
title_fullStr |
Lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season |
title_full_unstemmed |
Lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season |
title_sort |
lability of dissolved organic carbon from boreal peatlands: interactions between permafrost thaw, wildfire, and season |
publisher |
NRC Research Press (a division of Canadian Science Publishing) |
publishDate |
2020 |
url |
http://hdl.handle.net/1807/100202 http://www.nrcresearchpress.com/doi/abs/10.1139/CJSS-2019-0154 |
genre |
Peat Peat plateau permafrost Thermokarst |
genre_facet |
Peat Peat plateau permafrost Thermokarst |
op_relation |
0008 4271 http://hdl.handle.net/1807/100202 http://www.nrcresearchpress.com/doi/abs/10.1139/CJSS-2019-0154 |
_version_ |
1766162745347014656 |