Modeling anaerobic soil organic carbon decomposition in Arctic polygon tundra: insights into soil geochemical influences on carbon mineralization
Rapid warming of Arctic ecosystems exposes soil organic matter (SOM) to accelerated microbial decomposition, potentially leading to increased emissions of carbon dioxide ( CO 2 ) and methane ( CH 4 ) that have a positive feedback on global warming. Current estimates of the magnitude and form of carb...
Published in: | Biogeosciences |
---|---|
Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2019
|
Subjects: | |
Online Access: | https://doi.org/10.5194/bg-16-663-2019 https://doaj.org/article/bdb5bd8cee7746218bcddade419524f2 |
id |
ftdoajarticles:oai:doaj.org/article:bdb5bd8cee7746218bcddade419524f2 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:bdb5bd8cee7746218bcddade419524f2 2023-05-15T14:55:45+02:00 Modeling anaerobic soil organic carbon decomposition in Arctic polygon tundra: insights into soil geochemical influences on carbon mineralization J. Zheng P. E. Thornton S. L. Painter B. Gu S. D. Wullschleger D. E. Graham 2019-02-01T00:00:00Z https://doi.org/10.5194/bg-16-663-2019 https://doaj.org/article/bdb5bd8cee7746218bcddade419524f2 EN eng Copernicus Publications https://www.biogeosciences.net/16/663/2019/bg-16-663-2019.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 doi:10.5194/bg-16-663-2019 1726-4170 1726-4189 https://doaj.org/article/bdb5bd8cee7746218bcddade419524f2 Biogeosciences, Vol 16, Pp 663-680 (2019) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2019 ftdoajarticles https://doi.org/10.5194/bg-16-663-2019 2022-12-30T21:24:12Z Rapid warming of Arctic ecosystems exposes soil organic matter (SOM) to accelerated microbial decomposition, potentially leading to increased emissions of carbon dioxide ( CO 2 ) and methane ( CH 4 ) that have a positive feedback on global warming. Current estimates of the magnitude and form of carbon emissions from Earth system models include significant uncertainties, partially due to the oversimplified representation of geochemical constraints on microbial decomposition. Here, we coupled modeling principles developed in different disciplines, including a thermodynamically based microbial growth model for methanogenesis and iron reduction, a pool-based model to represent upstream carbon transformations, and a humic ion-binding model for dynamic pH simulation to build a more versatile carbon decomposition model framework that can be applied to soils under varying redox conditions. This new model framework was parameterized and validated using synthesized anaerobic incubation data from permafrost-affected soils along a gradient of fine-scale thermal and hydrological variabilities across Arctic polygonal tundra. The model accurately simulated anaerobic CO 2 production and its temperature sensitivity using data on labile carbon pools and fermentation rates as model constraints. CH 4 production is strongly influenced by water content, pH, methanogen biomass, and presence of competing electron acceptors, resulting in high variability in its temperature sensitivity. This work provides new insights into the interactions of SOM pools, temperature increase, soil geochemical feedbacks, and resulting CO 2 and CH 4 production. The proposed anaerobic carbon decomposition framework presented here builds a mechanistic link between soil geochemistry and carbon mineralization, making it applicable over a wide range of soils under different environmental settings. Article in Journal/Newspaper Arctic Global warming permafrost Tundra Directory of Open Access Journals: DOAJ Articles Arctic Biogeosciences 16 3 663 680 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
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 J. Zheng P. E. Thornton S. L. Painter B. Gu S. D. Wullschleger D. E. Graham Modeling anaerobic soil organic carbon decomposition in Arctic polygon tundra: insights into soil geochemical influences on carbon mineralization |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
description |
Rapid warming of Arctic ecosystems exposes soil organic matter (SOM) to accelerated microbial decomposition, potentially leading to increased emissions of carbon dioxide ( CO 2 ) and methane ( CH 4 ) that have a positive feedback on global warming. Current estimates of the magnitude and form of carbon emissions from Earth system models include significant uncertainties, partially due to the oversimplified representation of geochemical constraints on microbial decomposition. Here, we coupled modeling principles developed in different disciplines, including a thermodynamically based microbial growth model for methanogenesis and iron reduction, a pool-based model to represent upstream carbon transformations, and a humic ion-binding model for dynamic pH simulation to build a more versatile carbon decomposition model framework that can be applied to soils under varying redox conditions. This new model framework was parameterized and validated using synthesized anaerobic incubation data from permafrost-affected soils along a gradient of fine-scale thermal and hydrological variabilities across Arctic polygonal tundra. The model accurately simulated anaerobic CO 2 production and its temperature sensitivity using data on labile carbon pools and fermentation rates as model constraints. CH 4 production is strongly influenced by water content, pH, methanogen biomass, and presence of competing electron acceptors, resulting in high variability in its temperature sensitivity. This work provides new insights into the interactions of SOM pools, temperature increase, soil geochemical feedbacks, and resulting CO 2 and CH 4 production. The proposed anaerobic carbon decomposition framework presented here builds a mechanistic link between soil geochemistry and carbon mineralization, making it applicable over a wide range of soils under different environmental settings. |
format |
Article in Journal/Newspaper |
author |
J. Zheng P. E. Thornton S. L. Painter B. Gu S. D. Wullschleger D. E. Graham |
author_facet |
J. Zheng P. E. Thornton S. L. Painter B. Gu S. D. Wullschleger D. E. Graham |
author_sort |
J. Zheng |
title |
Modeling anaerobic soil organic carbon decomposition in Arctic polygon tundra: insights into soil geochemical influences on carbon mineralization |
title_short |
Modeling anaerobic soil organic carbon decomposition in Arctic polygon tundra: insights into soil geochemical influences on carbon mineralization |
title_full |
Modeling anaerobic soil organic carbon decomposition in Arctic polygon tundra: insights into soil geochemical influences on carbon mineralization |
title_fullStr |
Modeling anaerobic soil organic carbon decomposition in Arctic polygon tundra: insights into soil geochemical influences on carbon mineralization |
title_full_unstemmed |
Modeling anaerobic soil organic carbon decomposition in Arctic polygon tundra: insights into soil geochemical influences on carbon mineralization |
title_sort |
modeling anaerobic soil organic carbon decomposition in arctic polygon tundra: insights into soil geochemical influences on carbon mineralization |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/bg-16-663-2019 https://doaj.org/article/bdb5bd8cee7746218bcddade419524f2 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Global warming permafrost Tundra |
genre_facet |
Arctic Global warming permafrost Tundra |
op_source |
Biogeosciences, Vol 16, Pp 663-680 (2019) |
op_relation |
https://www.biogeosciences.net/16/663/2019/bg-16-663-2019.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 doi:10.5194/bg-16-663-2019 1726-4170 1726-4189 https://doaj.org/article/bdb5bd8cee7746218bcddade419524f2 |
op_doi |
https://doi.org/10.5194/bg-16-663-2019 |
container_title |
Biogeosciences |
container_volume |
16 |
container_issue |
3 |
container_start_page |
663 |
op_container_end_page |
680 |
_version_ |
1766327768515084288 |