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Neotropical peatland methane emissions along a vegetation and biogeochemical gradient

Tropical wetlands are thought to be the most important source of interannual variability in atmospheric methane (CH(4)) concentrations, yet sparse data prevents them from being incorporated into Earth system models. This problem is particularly pronounced in the neotropics where bottom-up models bas...

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Autores principales: Winton, R. Scott, Flanagan, Neal, Richardson, Curtis J.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5650183/
https://www.ncbi.nlm.nih.gov/pubmed/29053738
http://dx.doi.org/10.1371/journal.pone.0187019
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author Winton, R. Scott
Flanagan, Neal
Richardson, Curtis J.
author_facet Winton, R. Scott
Flanagan, Neal
Richardson, Curtis J.
author_sort Winton, R. Scott
collection PubMed
description Tropical wetlands are thought to be the most important source of interannual variability in atmospheric methane (CH(4)) concentrations, yet sparse data prevents them from being incorporated into Earth system models. This problem is particularly pronounced in the neotropics where bottom-up models based on water table depth are incongruent with top-down inversion models suggesting unaccounted sinks or sources of CH(4). The newly documented vast areas of peatlands in the Amazon basin may account for an important unrecognized CH(4) source, but the hydrologic and biogeochemical controls of CH(4) dynamics from these systems remain poorly understood. We studied three zones of a peatland in Madre de Dios, Peru, to test whether CH(4) emissions and pore water concentrations varied with vegetation community, soil chemistry and proximity to groundwater sources. We found that the open-canopy herbaceous zone emitted roughly one-third as much CH(4) as the Mauritia flexuosa palm-dominated areas (4.7 ± 0.9 and 14.0 ± 2.4 mg CH(4) m(-2) h(-1), respectively). Emissions decreased with distance from groundwater discharge across the three sampling sites, and tracked changes in soil carbon chemistry, especially increased soil phenolics. Based on all available data, we calculate that neotropical peatlands contribute emissions of 43 ± 11.9 Tg CH(4) y(-1), however this estimate is subject to geographic bias and will need revision once additional studies are published.
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spelling pubmed-56501832017-11-03 Neotropical peatland methane emissions along a vegetation and biogeochemical gradient Winton, R. Scott Flanagan, Neal Richardson, Curtis J. PLoS One Research Article Tropical wetlands are thought to be the most important source of interannual variability in atmospheric methane (CH(4)) concentrations, yet sparse data prevents them from being incorporated into Earth system models. This problem is particularly pronounced in the neotropics where bottom-up models based on water table depth are incongruent with top-down inversion models suggesting unaccounted sinks or sources of CH(4). The newly documented vast areas of peatlands in the Amazon basin may account for an important unrecognized CH(4) source, but the hydrologic and biogeochemical controls of CH(4) dynamics from these systems remain poorly understood. We studied three zones of a peatland in Madre de Dios, Peru, to test whether CH(4) emissions and pore water concentrations varied with vegetation community, soil chemistry and proximity to groundwater sources. We found that the open-canopy herbaceous zone emitted roughly one-third as much CH(4) as the Mauritia flexuosa palm-dominated areas (4.7 ± 0.9 and 14.0 ± 2.4 mg CH(4) m(-2) h(-1), respectively). Emissions decreased with distance from groundwater discharge across the three sampling sites, and tracked changes in soil carbon chemistry, especially increased soil phenolics. Based on all available data, we calculate that neotropical peatlands contribute emissions of 43 ± 11.9 Tg CH(4) y(-1), however this estimate is subject to geographic bias and will need revision once additional studies are published. Public Library of Science 2017-10-20 /pmc/articles/PMC5650183/ /pubmed/29053738 http://dx.doi.org/10.1371/journal.pone.0187019 Text en © 2017 Winton et al http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
spellingShingle Research Article
Winton, R. Scott
Flanagan, Neal
Richardson, Curtis J.
Neotropical peatland methane emissions along a vegetation and biogeochemical gradient
title Neotropical peatland methane emissions along a vegetation and biogeochemical gradient
title_full Neotropical peatland methane emissions along a vegetation and biogeochemical gradient
title_fullStr Neotropical peatland methane emissions along a vegetation and biogeochemical gradient
title_full_unstemmed Neotropical peatland methane emissions along a vegetation and biogeochemical gradient
title_short Neotropical peatland methane emissions along a vegetation and biogeochemical gradient
title_sort neotropical peatland methane emissions along a vegetation and biogeochemical gradient
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5650183/
https://www.ncbi.nlm.nih.gov/pubmed/29053738
http://dx.doi.org/10.1371/journal.pone.0187019
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