| 42123 |
Creator |
974e4843c2192d7cff8913fe9460740b |
| 42123 |
Creator |
9afccdbe975e25965953e777bb4d6a5f |
| 42123 |
Creator |
ext-0999e2ed3c0e010b60224fd892db17cd |
| 42123 |
Creator |
ext-0f149575c9c16eb37ad8f108517262f1 |
| 42123 |
Creator |
ext-415c0d572f8b51d5b980bed1c89ea448 |
| 42123 |
Creator |
ext-49a2c1237f5ea116d98eb5d6522ff2ac |
| 42123 |
Creator |
ext-52f9a1bcdc285a6d15009f1b5a2cae50 |
| 42123 |
Creator |
ext-8cc8bfb24ad7186ad3c2af4c6f5ef5cf |
| 42123 |
Creator |
ext-d16832a04b337d7e5773cfac61de6d29 |
| 42123 |
Creator |
ext-ea80dc8289bdb1adbcc58556278aa586 |
| 42123 |
Creator |
ext-f6dcfabcf7a606b029e5e6ca69db6198 |
| 42123 |
Date |
2014 |
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Is Part Of |
repository |
| 42123 |
abstract |
Wetlands are the largest source of CH<sub>4</sub> to the atmosphere, but emissions
measurements are highly uncertain, particularly in the tropics. We examine CH<sub>4</sub>
production and transport in a pristine tropical peatland in Borneo. We use the carbon
isotopic (stable and radioactive) composition of dissolved CH<sub>4</sub>, DIC and
DOC within the peat porewater to identify the source and mechanism of CH<sub>4</sub>
production in tropical peat. First, we measure <sup>14</sup>C in all carbon phases
to identify the source of CH<sub>4</sub>. In contrast to the peat, which ages with
depth to nearly 3000 cal BP, DOC is modern throughout the peat column, to depths of
4.5m. The <sup>14</sup>C content of CH<sub>4</sub> and DIC are nearly identical, and
are intermediate between the DOC and peat 14C content. Thus, despite the presence
of modern carbon throughout the peat profile, peat decomposition is an important source
of CH<sub>4</sub> production. Next, we use the δ<sup>13</sup>C of CH<sub>4</sub> and
DIC to identify the mechanism of CH<sub>4</sub> production. Within the peat profile,
CH<sub>4</sub> and DIC concentrations increase with depth and DIC becomes increasingly
enriched in <sup>13</sup>C. The δ<sup>13</sup>C of CH<sub>4</sub> is relatively uniform
with depth, resulting in a δ<sup>13</sup>C fractionation between DIC and CH<sub>4</sub>
of 55-70‰ (α<sub>C</sub>CO<sub>2</sub>-CH<sub>4</sub> = 1.06-1.07). This fractionation
suggests CO<sub>2</sub> reduction is the dominant pathway for CH<sub>4</sub> production
at the site. We find consistent trends with depth across the peatland, attributable
to the unique hydrologic behavior of the dome. These trends are similar to those observed
in northern peat bogs. Finally, we use information on site hydrology, CH<sub>4</sub>
and DIC concentrations, isotopic compositions and fluxes to build a model of CH<sub>4</sub>
production and transport. This model allows us to partition CH<sub>4</sub> losses
from the peat due to diffusion, tree-mediated transport, and ebullition. |
| 42123 |
authorList |
authors |
| 42123 |
presentedAt |
ext-2ef34a6047275c1fc4ce06b08d748c34 |
| 42123 |
status |
nonPeerReviewed |
| 42123 |
type |
AcademicArticle |
| 42123 |
type |
Article |
| 42123 |
label |
Hoyt, Alison; Pangala, Sunitha ; Gandois, Laure; Cobb, Alex; Kai, Fuu-Ming; Xu, Xiaomei;
Gauci, Vincent ; Mahmud, Y.; Kamariah, A.; Eri, Jangarun and Harvey, Charles (2014).
Methane production and transport in a tropical peatland. In: AGU Fall Meeting, 15-19
Dec 2014, San Francisco, CA, USA. |
| 42123 |
label |
Hoyt, Alison; Pangala, Sunitha ; Gandois, Laure; Cobb, Alex; Kai, Fuu-Ming; Xu,
Xiaomei; Gauci, Vincent ; Mahmud, Y.; Kamariah, A.; Eri, Jangarun and Harvey, Charles
(2014). Methane production and transport in a tropical peatland. In: AGU Fall Meeting,
15-19 Dec 2014, San Francisco, CA, USA. |
| 42123 |
Title |
Methane production and transport in a tropical peatland |
| 42123 |
in dataset |
oro |