Grazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra site
Large-herbivore grazing has been shown to substantially alter tundra soil and vegetation properties as well as carbon fluxes, yet observational evidence to quantify the impact of herbivore introduction into Arctic permafrost ecosystems remains sparse. In this study we investigated growing-season CO...
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ftdoajarticles:oai:doaj.org/article:09f2a98c7ef244f59dbbfcdf67114bc4 2023-05-15T15:14:20+02:00 Grazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra site W. Fischer C. K. Thomas N. Zimov M. Göckede 2022-03-01T00:00:00Z https://doi.org/10.5194/bg-19-1611-2022 https://doaj.org/article/09f2a98c7ef244f59dbbfcdf67114bc4 EN eng Copernicus Publications https://bg.copernicus.org/articles/19/1611/2022/bg-19-1611-2022.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 doi:10.5194/bg-19-1611-2022 1726-4170 1726-4189 https://doaj.org/article/09f2a98c7ef244f59dbbfcdf67114bc4 Biogeosciences, Vol 19, Pp 1611-1633 (2022) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2022 ftdoajarticles https://doi.org/10.5194/bg-19-1611-2022 2022-12-31T05:35:20Z Large-herbivore grazing has been shown to substantially alter tundra soil and vegetation properties as well as carbon fluxes, yet observational evidence to quantify the impact of herbivore introduction into Arctic permafrost ecosystems remains sparse. In this study we investigated growing-season CO 2 and CH 4 fluxes with flux chambers on a former wet tussock tundra inside Pleistocene Park, a landscape experiment in northeast Siberia with a 22-year history of grazing. Reference data for an undisturbed system were collected on a nearby ungrazed tussock tundra. Linked to a reduction in soil moisture, topsoil temperatures at the grazed site reacted 1 order of magnitude faster to changes in air temperatures compared to the ungrazed site and were significantly higher, and the difference strongly decreased with depth. Overall, both GPP (gross primary productivity, i.e., CO 2 uptake by photosynthesis) and R eco (ecosystem respiration, i.e., CO 2 release from the ecosystem) were significantly higher at the grazed site with notable variations across plots at each site. The increases in CO 2 component fluxes largely compensated for each other, leaving NEE (net ecosystem exchange) similar across grazed and ungrazed sites for the observation period. Soil moisture and CH 4 fluxes at the grazed site decreased over the observation period, while in contrast the constantly waterlogged soils at the ungrazed site kept CH 4 fluxes at significantly higher levels. Our results indicate that grazing of large herbivores may promote topsoil warming and drying, in this way effectively accelerating CO 2 turnover while decreasing methane emissions in the summer months of peak ecosystem activity. Since we lack quantitative information on the pre-treatment status of the grazed ecosystem, however, these findings need to be considered qualitative trends for the peak growing season, and absolute differences between treatments are subject to elevated uncertainty. Moreover, our experiment did not include autumn and winter fluxes, and thus no ... Article in Journal/Newspaper Arctic permafrost Tundra Siberia Directory of Open Access Journals: DOAJ Articles Arctic Biogeosciences 19 6 1611 1633 |
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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 |
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Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 W. Fischer C. K. Thomas N. Zimov M. Göckede Grazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra site |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
description |
Large-herbivore grazing has been shown to substantially alter tundra soil and vegetation properties as well as carbon fluxes, yet observational evidence to quantify the impact of herbivore introduction into Arctic permafrost ecosystems remains sparse. In this study we investigated growing-season CO 2 and CH 4 fluxes with flux chambers on a former wet tussock tundra inside Pleistocene Park, a landscape experiment in northeast Siberia with a 22-year history of grazing. Reference data for an undisturbed system were collected on a nearby ungrazed tussock tundra. Linked to a reduction in soil moisture, topsoil temperatures at the grazed site reacted 1 order of magnitude faster to changes in air temperatures compared to the ungrazed site and were significantly higher, and the difference strongly decreased with depth. Overall, both GPP (gross primary productivity, i.e., CO 2 uptake by photosynthesis) and R eco (ecosystem respiration, i.e., CO 2 release from the ecosystem) were significantly higher at the grazed site with notable variations across plots at each site. The increases in CO 2 component fluxes largely compensated for each other, leaving NEE (net ecosystem exchange) similar across grazed and ungrazed sites for the observation period. Soil moisture and CH 4 fluxes at the grazed site decreased over the observation period, while in contrast the constantly waterlogged soils at the ungrazed site kept CH 4 fluxes at significantly higher levels. Our results indicate that grazing of large herbivores may promote topsoil warming and drying, in this way effectively accelerating CO 2 turnover while decreasing methane emissions in the summer months of peak ecosystem activity. Since we lack quantitative information on the pre-treatment status of the grazed ecosystem, however, these findings need to be considered qualitative trends for the peak growing season, and absolute differences between treatments are subject to elevated uncertainty. Moreover, our experiment did not include autumn and winter fluxes, and thus no ... |
format |
Article in Journal/Newspaper |
author |
W. Fischer C. K. Thomas N. Zimov M. Göckede |
author_facet |
W. Fischer C. K. Thomas N. Zimov M. Göckede |
author_sort |
W. Fischer |
title |
Grazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra site |
title_short |
Grazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra site |
title_full |
Grazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra site |
title_fullStr |
Grazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra site |
title_full_unstemmed |
Grazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra site |
title_sort |
grazing enhances carbon cycling but reduces methane emission during peak growing season in the siberian pleistocene park tundra site |
publisher |
Copernicus Publications |
publishDate |
2022 |
url |
https://doi.org/10.5194/bg-19-1611-2022 https://doaj.org/article/09f2a98c7ef244f59dbbfcdf67114bc4 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic permafrost Tundra Siberia |
genre_facet |
Arctic permafrost Tundra Siberia |
op_source |
Biogeosciences, Vol 19, Pp 1611-1633 (2022) |
op_relation |
https://bg.copernicus.org/articles/19/1611/2022/bg-19-1611-2022.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 doi:10.5194/bg-19-1611-2022 1726-4170 1726-4189 https://doaj.org/article/09f2a98c7ef244f59dbbfcdf67114bc4 |
op_doi |
https://doi.org/10.5194/bg-19-1611-2022 |
container_title |
Biogeosciences |
container_volume |
19 |
container_issue |
6 |
container_start_page |
1611 |
op_container_end_page |
1633 |
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