Long-term drainage reduces CO 2 uptake and increases CO 2 emission on a Siberian floodplain due to shifts in vegetation community and soil thermal characteristics
With increasing air temperatures and changing precipitation patterns forecast for the Arctic over the coming decades, the thawing of ice-rich permafrost is expected to increasingly alter hydrological conditions by creating mosaics of wetter and drier areas. The objective of this study is to investig...
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Online Access: | https://doi.org/10.5194/bg-13-4219-2016 https://doaj.org/article/8e6ac010abf849839877e51f1f6769d1 |
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ftdoajarticles:oai:doaj.org/article:8e6ac010abf849839877e51f1f6769d1 2023-05-15T15:16:50+02:00 Long-term drainage reduces CO 2 uptake and increases CO 2 emission on a Siberian floodplain due to shifts in vegetation community and soil thermal characteristics M. J. Kwon M. Heimann O. Kolle K. A. Luus E. A. G. Schuur N. Zimov S. A. Zimov M. Göckede 2016-07-01T00:00:00Z https://doi.org/10.5194/bg-13-4219-2016 https://doaj.org/article/8e6ac010abf849839877e51f1f6769d1 EN eng Copernicus Publications http://www.biogeosciences.net/13/4219/2016/bg-13-4219-2016.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 doi:10.5194/bg-13-4219-2016 https://doaj.org/article/8e6ac010abf849839877e51f1f6769d1 Biogeosciences, Vol 13, Iss 14, Pp 4219-4235 (2016) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2016 ftdoajarticles https://doi.org/10.5194/bg-13-4219-2016 2022-12-31T00:26:21Z With increasing air temperatures and changing precipitation patterns forecast for the Arctic over the coming decades, the thawing of ice-rich permafrost is expected to increasingly alter hydrological conditions by creating mosaics of wetter and drier areas. The objective of this study is to investigate how 10 years of lowered water table depths of wet floodplain ecosystems would affect CO 2 fluxes measured using a closed chamber system, focusing on the role of long-term changes in soil thermal characteristics and vegetation community structure. Drainage diminishes the heat capacity and thermal conductivity of organic soil, leading to warmer soil temperatures in shallow layers during the daytime and colder soil temperatures in deeper layers, resulting in a reduction in thaw depths. These soil temperature changes can intensify growing-season heterotrophic respiration by up to 95 %. With decreased autotrophic respiration due to reduced gross primary production under these dry conditions, the differences in ecosystem respiration rates in the present study were 25 %. We also found that a decade-long drainage installation significantly increased shrub abundance, while decreasing Eriophorum angustifolium abundance resulted in Carex sp. dominance. These two changes had opposing influences on gross primary production during the growing season: while the increased abundance of shrubs slightly increased gross primary production, the replacement of E. angustifolium by Carex sp. significantly decreased it. With the effects of ecosystem respiration and gross primary production combined, net CO 2 uptake rates varied between the two years, which can be attributed to Carex -dominated plots' sensitivity to climate. However, underlying processes showed consistent patterns: 10 years of drainage increased soil temperatures in shallow layers and replaced E. angustifolium by Carex sp., which increased CO 2 emission and reduced CO 2 uptake rates. During the non-growing season, drainage resulted in 4 times more CO 2 emissions, with high ... Article in Journal/Newspaper Arctic Eriophorum Ice permafrost Directory of Open Access Journals: DOAJ Articles Arctic Biogeosciences 13 14 4219 4235 |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
spellingShingle |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 M. J. Kwon M. Heimann O. Kolle K. A. Luus E. A. G. Schuur N. Zimov S. A. Zimov M. Göckede Long-term drainage reduces CO 2 uptake and increases CO 2 emission on a Siberian floodplain due to shifts in vegetation community and soil thermal characteristics |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
description |
With increasing air temperatures and changing precipitation patterns forecast for the Arctic over the coming decades, the thawing of ice-rich permafrost is expected to increasingly alter hydrological conditions by creating mosaics of wetter and drier areas. The objective of this study is to investigate how 10 years of lowered water table depths of wet floodplain ecosystems would affect CO 2 fluxes measured using a closed chamber system, focusing on the role of long-term changes in soil thermal characteristics and vegetation community structure. Drainage diminishes the heat capacity and thermal conductivity of organic soil, leading to warmer soil temperatures in shallow layers during the daytime and colder soil temperatures in deeper layers, resulting in a reduction in thaw depths. These soil temperature changes can intensify growing-season heterotrophic respiration by up to 95 %. With decreased autotrophic respiration due to reduced gross primary production under these dry conditions, the differences in ecosystem respiration rates in the present study were 25 %. We also found that a decade-long drainage installation significantly increased shrub abundance, while decreasing Eriophorum angustifolium abundance resulted in Carex sp. dominance. These two changes had opposing influences on gross primary production during the growing season: while the increased abundance of shrubs slightly increased gross primary production, the replacement of E. angustifolium by Carex sp. significantly decreased it. With the effects of ecosystem respiration and gross primary production combined, net CO 2 uptake rates varied between the two years, which can be attributed to Carex -dominated plots' sensitivity to climate. However, underlying processes showed consistent patterns: 10 years of drainage increased soil temperatures in shallow layers and replaced E. angustifolium by Carex sp., which increased CO 2 emission and reduced CO 2 uptake rates. During the non-growing season, drainage resulted in 4 times more CO 2 emissions, with high ... |
format |
Article in Journal/Newspaper |
author |
M. J. Kwon M. Heimann O. Kolle K. A. Luus E. A. G. Schuur N. Zimov S. A. Zimov M. Göckede |
author_facet |
M. J. Kwon M. Heimann O. Kolle K. A. Luus E. A. G. Schuur N. Zimov S. A. Zimov M. Göckede |
author_sort |
M. J. Kwon |
title |
Long-term drainage reduces CO 2 uptake and increases CO 2 emission on a Siberian floodplain due to shifts in vegetation community and soil thermal characteristics |
title_short |
Long-term drainage reduces CO 2 uptake and increases CO 2 emission on a Siberian floodplain due to shifts in vegetation community and soil thermal characteristics |
title_full |
Long-term drainage reduces CO 2 uptake and increases CO 2 emission on a Siberian floodplain due to shifts in vegetation community and soil thermal characteristics |
title_fullStr |
Long-term drainage reduces CO 2 uptake and increases CO 2 emission on a Siberian floodplain due to shifts in vegetation community and soil thermal characteristics |
title_full_unstemmed |
Long-term drainage reduces CO 2 uptake and increases CO 2 emission on a Siberian floodplain due to shifts in vegetation community and soil thermal characteristics |
title_sort |
long-term drainage reduces co 2 uptake and increases co 2 emission on a siberian floodplain due to shifts in vegetation community and soil thermal characteristics |
publisher |
Copernicus Publications |
publishDate |
2016 |
url |
https://doi.org/10.5194/bg-13-4219-2016 https://doaj.org/article/8e6ac010abf849839877e51f1f6769d1 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Eriophorum Ice permafrost |
genre_facet |
Arctic Eriophorum Ice permafrost |
op_source |
Biogeosciences, Vol 13, Iss 14, Pp 4219-4235 (2016) |
op_relation |
http://www.biogeosciences.net/13/4219/2016/bg-13-4219-2016.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 doi:10.5194/bg-13-4219-2016 https://doaj.org/article/8e6ac010abf849839877e51f1f6769d1 |
op_doi |
https://doi.org/10.5194/bg-13-4219-2016 |
container_title |
Biogeosciences |
container_volume |
13 |
container_issue |
14 |
container_start_page |
4219 |
op_container_end_page |
4235 |
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1766347127885135872 |