Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence
Permafrost soils store over half of global soil carbon (C), and northern frozen peatlands store about 10% of global permafrost C. With thaw, inundation of high latitude lowland peatlands typically increases the surface-atmosphere flux of methane (CH _4 ), a potent greenhouse gas. To examine the effe...
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Online Access: | https://doi.org/10.1088/1748-9326/9/8/085004 https://doaj.org/article/f4c71066eb23456abd4e1f4dc8f89040 |
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ftdoajarticles:oai:doaj.org/article:f4c71066eb23456abd4e1f4dc8f89040 2023-09-05T13:22:29+02:00 Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence Carmel E Johnston Stephanie A Ewing Jennifer W Harden Ruth K Varner Kimberly P Wickland Joshua C Koch Christopher C Fuller Kristen Manies M Torre Jorgenson 2014-01-01T00:00:00Z https://doi.org/10.1088/1748-9326/9/8/085004 https://doaj.org/article/f4c71066eb23456abd4e1f4dc8f89040 EN eng IOP Publishing https://doi.org/10.1088/1748-9326/9/8/085004 https://doaj.org/toc/1748-9326 doi:10.1088/1748-9326/9/8/085004 1748-9326 https://doaj.org/article/f4c71066eb23456abd4e1f4dc8f89040 Environmental Research Letters, Vol 9, Iss 8, p 085004 (2014) methane wetlands permafrost carbon dioxide climate change Environmental technology. Sanitary engineering TD1-1066 Environmental sciences GE1-350 Science Q Physics QC1-999 article 2014 ftdoajarticles https://doi.org/10.1088/1748-9326/9/8/085004 2023-08-13T00:37:22Z Permafrost soils store over half of global soil carbon (C), and northern frozen peatlands store about 10% of global permafrost C. With thaw, inundation of high latitude lowland peatlands typically increases the surface-atmosphere flux of methane (CH _4 ), a potent greenhouse gas. To examine the effects of lowland permafrost thaw over millennial timescales, we measured carbon dioxide (CO _2 ) and CH _4 exchange along sites that constitute a ∼1000 yr thaw chronosequence of thermokarst collapse bogs and adjacent fen locations at Innoko Flats Wildlife Refuge in western Alaska. Peak CH _4 exchange in July (123 ± 71 mg CH _4 –C m ^−2 d ^−1 ) was observed in features that have been thawed for 30 to 70 (<100) yr, where soils were warmer than at more recently thawed sites (14 to 21 yr; emitting 1.37 ± 0.67 mg CH _4 –C m ^−2 d ^−1 in July) and had shallower water tables than at older sites (200 to 1400 yr; emitting 6.55 ± 2.23 mg CH _4 –C m ^−2 d ^−1 in July). Carbon lost via CH _4 efflux during the growing season at these intermediate age sites was 8% of uptake by net ecosystem exchange. Our results provide evidence that CH _4 emissions following lowland permafrost thaw are enhanced over decadal time scales, but limited over millennia. Over larger spatial scales, adjacent fen systems may contribute sustained CH _4 emission, CO _2 uptake, and DOC export. We argue that over timescales of decades to centuries, thaw features in high-latitude lowland peatlands, particularly those developed on poorly drained mineral substrates, are a key locus of elevated CH _4 emission to the atmosphere that must be considered for a complete understanding of high latitude CH _4 dynamics. Article in Journal/Newspaper permafrost Thermokarst Alaska Directory of Open Access Journals: DOAJ Articles Environmental Research Letters 9 8 085004 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
methane wetlands permafrost carbon dioxide climate change Environmental technology. Sanitary engineering TD1-1066 Environmental sciences GE1-350 Science Q Physics QC1-999 |
spellingShingle |
methane wetlands permafrost carbon dioxide climate change Environmental technology. Sanitary engineering TD1-1066 Environmental sciences GE1-350 Science Q Physics QC1-999 Carmel E Johnston Stephanie A Ewing Jennifer W Harden Ruth K Varner Kimberly P Wickland Joshua C Koch Christopher C Fuller Kristen Manies M Torre Jorgenson Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence |
topic_facet |
methane wetlands permafrost carbon dioxide climate change Environmental technology. Sanitary engineering TD1-1066 Environmental sciences GE1-350 Science Q Physics QC1-999 |
description |
Permafrost soils store over half of global soil carbon (C), and northern frozen peatlands store about 10% of global permafrost C. With thaw, inundation of high latitude lowland peatlands typically increases the surface-atmosphere flux of methane (CH _4 ), a potent greenhouse gas. To examine the effects of lowland permafrost thaw over millennial timescales, we measured carbon dioxide (CO _2 ) and CH _4 exchange along sites that constitute a ∼1000 yr thaw chronosequence of thermokarst collapse bogs and adjacent fen locations at Innoko Flats Wildlife Refuge in western Alaska. Peak CH _4 exchange in July (123 ± 71 mg CH _4 –C m ^−2 d ^−1 ) was observed in features that have been thawed for 30 to 70 (<100) yr, where soils were warmer than at more recently thawed sites (14 to 21 yr; emitting 1.37 ± 0.67 mg CH _4 –C m ^−2 d ^−1 in July) and had shallower water tables than at older sites (200 to 1400 yr; emitting 6.55 ± 2.23 mg CH _4 –C m ^−2 d ^−1 in July). Carbon lost via CH _4 efflux during the growing season at these intermediate age sites was 8% of uptake by net ecosystem exchange. Our results provide evidence that CH _4 emissions following lowland permafrost thaw are enhanced over decadal time scales, but limited over millennia. Over larger spatial scales, adjacent fen systems may contribute sustained CH _4 emission, CO _2 uptake, and DOC export. We argue that over timescales of decades to centuries, thaw features in high-latitude lowland peatlands, particularly those developed on poorly drained mineral substrates, are a key locus of elevated CH _4 emission to the atmosphere that must be considered for a complete understanding of high latitude CH _4 dynamics. |
format |
Article in Journal/Newspaper |
author |
Carmel E Johnston Stephanie A Ewing Jennifer W Harden Ruth K Varner Kimberly P Wickland Joshua C Koch Christopher C Fuller Kristen Manies M Torre Jorgenson |
author_facet |
Carmel E Johnston Stephanie A Ewing Jennifer W Harden Ruth K Varner Kimberly P Wickland Joshua C Koch Christopher C Fuller Kristen Manies M Torre Jorgenson |
author_sort |
Carmel E Johnston |
title |
Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence |
title_short |
Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence |
title_full |
Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence |
title_fullStr |
Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence |
title_full_unstemmed |
Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence |
title_sort |
effect of permafrost thaw on co2 and ch4 exchange in a western alaska peatland chronosequence |
publisher |
IOP Publishing |
publishDate |
2014 |
url |
https://doi.org/10.1088/1748-9326/9/8/085004 https://doaj.org/article/f4c71066eb23456abd4e1f4dc8f89040 |
genre |
permafrost Thermokarst Alaska |
genre_facet |
permafrost Thermokarst Alaska |
op_source |
Environmental Research Letters, Vol 9, Iss 8, p 085004 (2014) |
op_relation |
https://doi.org/10.1088/1748-9326/9/8/085004 https://doaj.org/toc/1748-9326 doi:10.1088/1748-9326/9/8/085004 1748-9326 https://doaj.org/article/f4c71066eb23456abd4e1f4dc8f89040 |
op_doi |
https://doi.org/10.1088/1748-9326/9/8/085004 |
container_title |
Environmental Research Letters |
container_volume |
9 |
container_issue |
8 |
container_start_page |
085004 |
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1776203009598947328 |