Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands
Large tracts of arctic and subarctic peatlands are underlain by permafrost. These peatlands store large quantities of carbon (C), and are currently under severe threat from climate change. The aim of this study was to determine the size and organic chemistry of the easily degradable C pool in permaf...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Published: |
Elsevier
2016
|
| Subjects: | |
| Online Access: | https://eprints.nottingham.ac.uk/45401/ |
| _version_ | 1848797124003627008 |
|---|---|
| author | Sjögersten, Sofie Caul, S. Daniell, T.J. Jurd, A.P.S. O'Sullivan, O.S. Stapleton, C.S. Titman, Jeremy J. |
| author_facet | Sjögersten, Sofie Caul, S. Daniell, T.J. Jurd, A.P.S. O'Sullivan, O.S. Stapleton, C.S. Titman, Jeremy J. |
| author_sort | Sjögersten, Sofie |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | Large tracts of arctic and subarctic peatlands are underlain by permafrost. These peatlands store large quantities of carbon (C), and are currently under severe threat from climate change. The aim of this study was to determine the size and organic chemistry of the easily degradable C pool in permafrost peatlands and link the functional organic chemistry to temperature and moisture controls of greenhouse gas emissions. First, we used a combination of field measurements and laboratory experiments to assess the influence of increased temperature and flooding on CO₂ and CH₄ emissions from sixteen permafrost peatlands in subarctic Sweden and Canada. Second, we determined the variation in organic matter chemistry and the associated microbial community composition of the peat active layer, with depth using quantitative ¹³C solid-state NMR and molecular biomarkers respectively. We demonstrate that the peat organic chemistry strongly controls CO₂ release from peat and that ca. 35 and 26% of the peat organic matter, at the Swedish and Canadian peatlands sites, respectively, is easily degradable by heterotrophic microorganisms. In contrast to CO₂, CH₄ emissions were decoupled from peat functional organic chemistry. We show a strong relationship between the microbial community structure and the peat organic chemistry suggesting that substrate type and abundance is an important driver of microbial composition in sub-arctic peatlands. Despite considerable variation in peat chemistry and microbial community composition with depth the temperature sensitivity was comparable throughout the active layer. Our study shows that functional organic chemistry controls both soil respiration rates and the composition of the microbial community. Furthermore, if these peatlands collapse and flood on thawing, they are unlikely to become large emitters of CH₄ without additional input of labile substrates. |
| first_indexed | 2025-11-14T19:58:53Z |
| format | Article |
| id | nottingham-45401 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:58:53Z |
| publishDate | 2016 |
| publisher | Elsevier |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-454012020-05-04T17:54:12Z https://eprints.nottingham.ac.uk/45401/ Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands Sjögersten, Sofie Caul, S. Daniell, T.J. Jurd, A.P.S. O'Sullivan, O.S. Stapleton, C.S. Titman, Jeremy J. Large tracts of arctic and subarctic peatlands are underlain by permafrost. These peatlands store large quantities of carbon (C), and are currently under severe threat from climate change. The aim of this study was to determine the size and organic chemistry of the easily degradable C pool in permafrost peatlands and link the functional organic chemistry to temperature and moisture controls of greenhouse gas emissions. First, we used a combination of field measurements and laboratory experiments to assess the influence of increased temperature and flooding on CO₂ and CH₄ emissions from sixteen permafrost peatlands in subarctic Sweden and Canada. Second, we determined the variation in organic matter chemistry and the associated microbial community composition of the peat active layer, with depth using quantitative ¹³C solid-state NMR and molecular biomarkers respectively. We demonstrate that the peat organic chemistry strongly controls CO₂ release from peat and that ca. 35 and 26% of the peat organic matter, at the Swedish and Canadian peatlands sites, respectively, is easily degradable by heterotrophic microorganisms. In contrast to CO₂, CH₄ emissions were decoupled from peat functional organic chemistry. We show a strong relationship between the microbial community structure and the peat organic chemistry suggesting that substrate type and abundance is an important driver of microbial composition in sub-arctic peatlands. Despite considerable variation in peat chemistry and microbial community composition with depth the temperature sensitivity was comparable throughout the active layer. Our study shows that functional organic chemistry controls both soil respiration rates and the composition of the microbial community. Furthermore, if these peatlands collapse and flood on thawing, they are unlikely to become large emitters of CH₄ without additional input of labile substrates. Elsevier 2016-07-01 Article PeerReviewed Sjögersten, Sofie, Caul, S., Daniell, T.J., Jurd, A.P.S., O'Sullivan, O.S., Stapleton, C.S. and Titman, Jeremy J. (2016) Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands. Soil Biology and Biochemistry, 98 . pp. 42-53. ISSN 0038-0717 ¹³C solid-state NMR; Carbon dioxide; Climate change; Methane; Microbial; Permafrost peatland http://www.sciencedirect.com/science/article/pii/S0038071716300256 doi:10.1016/j.soilbio.2016.03.016 doi:10.1016/j.soilbio.2016.03.016 |
| spellingShingle | ¹³C solid-state NMR; Carbon dioxide; Climate change; Methane; Microbial; Permafrost peatland Sjögersten, Sofie Caul, S. Daniell, T.J. Jurd, A.P.S. O'Sullivan, O.S. Stapleton, C.S. Titman, Jeremy J. Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands |
| title | Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands |
| title_full | Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands |
| title_fullStr | Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands |
| title_full_unstemmed | Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands |
| title_short | Organic matter chemistry controls greenhouse gas emissions from permafrost peatlands |
| title_sort | organic matter chemistry controls greenhouse gas emissions from permafrost peatlands |
| topic | ¹³C solid-state NMR; Carbon dioxide; Climate change; Methane; Microbial; Permafrost peatland |
| url | https://eprints.nottingham.ac.uk/45401/ https://eprints.nottingham.ac.uk/45401/ https://eprints.nottingham.ac.uk/45401/ |