Carbon Dioxide and Methane Dynamics in a Peatland Headwater Stream: Origins, Processes and Implications
Carbon Dioxide and Methane Dynamics in a Peatland Headwater Stream: Origins, Processes and Implications
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泥炭地源头水流中的二氧化碳和甲烷动力学：起源、过程和影响
DOI：
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
M. Garneau
中科院分区：
文献类型：
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作者：
P. Taillardat;P. Bodmer;Charles P. Deblois;Alex Ponçot;Antonin Prijac;Khawla Riahi;L. Gandois;P. D. del Giorgio;M. Bourgault;A. Tremblay;M. Garneau
流经泥炭地的一级溪流接收、携带和转化大量的有机碳、甲烷（CH 4）和二氧化碳（CO2），但记录仍然很少。本研究的目标是：（a）确定泥炭地源头流中CO2和CH 4（此后为碳温室气体的C-GHG）的来源，（B）确定驱动C-GHG输出和排放的环境因素，以及（c）量化该系统的C-GHG损失并讨论其影响。数据是在2019年和2020年生长季节从沿着3公里长的北方泥炭地源头溪流（加拿大东部）的8个采样点收集的。所研究的流在pCO 2 [min：2，044; max：23，306 μatm]和pCH 4 [14; 17，614 μatm]中过饱和。质量平衡模型表明，81%的流内CO2来自孔隙水渗流，而其余的17%和2%分别来自流内生产力和甲烷氧化。孔隙水渗漏被认为是甲烷的主要来源。季节性溶解的C-GHG浓度与泥炭地地下水位深度呈负相关，这表明在基流期间富碳泥炭孔隙水的主动释放。尽管如此，在暴雨期间发生了更大的C-GHG损失，这相当于大部分C-GHG被分流到下游的脉冲。我们工厂的C-GHG输出和排放总量为8.08 gC m−2 y−1，其中86%被释放到大气中，14%被输出到下游。我们的研究表明，泥炭地源头流作为C-GHG的大来源，降水事件和地形控制通量的大小。
First‐order streams flowing through peatlands receive, carry and transform large amounts of organic carbon, methane (CH4) and carbon dioxide (CO2) but remain poorly documented. The objectives of this study were to (a) identify the origins of CO2 and CH4 (thereafter C‐GHG for carbon greenhouse gases) in a peatland headwater stream, (b) determine the environmental factors driving C‐GHG export and emissions, and (c) quantify C‐GHG losses from this system and discuss its implications. Data were collected from eight sampling sites along a 3 km boreal peatland headwater stream (Eastern Canada) over the growing seasons 2019 and 2020. The studied stream was oversaturated in pCO2 [min: 2,044; max: 23,306 μatm] and pCH4 [14; 17,614 μatm]. A mass balance model showed that ∼81% of in‐stream CO2 originated from porewater seepage while the remaining 17% and 2% originated from in‐stream productivity and methane oxidation, respectively. Porewater seepage was concluded to be the primary source of CH4. Seasonal dissolved C‐GHG concentrations were negatively correlated with the peatland water table depth, suggesting an active release of carbon‐rich peat porewater during the base flow. Nevertheless, greater C‐GHG losses occurred during stormflow periods which acted as pulses with most of the C‐GHG being shunted downstream. The sum of C‐GHG export and emissions at our site was 8.08 gC m−2 y−1 with 86% being released to the atmosphere and 14% being exported downstream. Our study demonstrates that peatland headwater streams act as large sources of C‐GHG and that precipitation events and topography control the magnitude of the fluxes.
影响因子：
3.2
作者：
R. Geldern;P. Schulte;Michael Mader;Alfons Baier;J. Barth
通讯作者：
R. Geldern;P. Schulte;Michael Mader;Alfons Baier;J. Barth
影响因子：
2.7
作者：
Shelley, Felicity;Abdullahi, Frah;Trimmer, Mark
通讯作者：
Trimmer, Mark
使用两种独立方法研究热带高海拔气流中气体传输速度的时空变化
影响因子：
2.7
作者：
Whitmore, Keridwen M.;Stewart, Nehemiah;Encalada, Andrea C.;Suárez, Esteban;Riveros‐Iregui, Diego A.
通讯作者：
Riveros‐Iregui, Diego A.