Redox dynamics in the active layer of an Arctic headwater catchment; examining the potential for transfer of dissolved methane from soils to stream water
Redox dynamics in the active layer of an Arctic headwater catchment; examining the potential for transfer of dissolved methane from soils to stream water
复制标题
北极源头流域活性层的氧化还原动力学；
DOI：
10.1002/2016jg003387
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发表时间：
2016
期刊：
影响因子：
4.9
通讯作者：
Street L
中科院分区：
文献类型：
--
作者：
Street L
陆地和水生系统的甲烷生产、运输和释放之间的联系还没有得到很好的理解，这使得预测甲烷排放的任务变得复杂。我们提供了新的数据，研究了加拿大北方连续多年冻土区源头集水区内活动层土壤饱和区通过土壤水排放作为溶解甲烷向水生系统来源的潜力。我们监测氧化还原条件和土壤甲烷浓度的土壤剖面从中游到山坡的横断面和比较的时间模式在土壤中的甲烷浓度的流。我们发现，在活跃层土壤中的氧化还原条件变得更加消极的解冻季节的进展，提供条件适合净产甲烷和氧化还原条件是敏感的增加降水在风暴事件，但仅在较浅的表层土壤。虽然我们证明，在山坡土壤中的甲烷浓度在深度增加的过程中的生长季节减少条件的发展，我们没有发现证据表明，这对溪流中的甲烷浓度的影响。然而，直接位于河床下方的沉积物在整个解冻季节的深度仍然强烈减少，并且含有比山坡土壤中浓度高5个数量级的甲烷。substreambed甲烷源的程度，从这些区域的甲烷运输的速率，因此，可能是重要的因素，确定在不断变化的北极水文制度的源头流甲烷浓度。
The linkages between methane production, transport, and release from terrestrial and aquatic systems are not well understood, complicating the task of predicting methane emissions. We present novel data examining the potential for the saturated zone of active layer soils to act as a source of dissolved methane to the aquatic system, via soil water discharge, within a headwater catchment of the continuous permafrost zone in Northern Canada. We monitored redox conditions and soil methane concentrations across a transect of soil profiles from midstream to hillslope and compare temporal patterns in methane concentrations in soils to those in the stream. We show that redox conditions in active layer soils become more negative as the thaw season progresses, providing conditions suitable for net methanogenesis and that redox conditions are sensitive to increased precipitation during a storm event—but only in shallower surface soil layers. While we demonstrate that methane concentrations at depth in the hillslope soils increase over the course of the growing season as reducing conditions develop, we find no evidence that this has an influence on stream water methane concentrations. Sediments directly beneath the stream bed, however, remain strongly reducing at depth throughout the thaw season and contain methane at concentrations 5 orders of magnitude greater than those in hillslope soils. The extent of substreambed methane sources, and the rates of methane transport from these zones, may therefore be important factors determining headwater stream methane concentrations under changing Arctic hydrologic regimes.
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加拿大西北地区北极苔原径流化学的转变
影响因子：
3.2
作者：
W. Quinton;J. Pomeroy
通讯作者：
J. Pomeroy
影响因子：
0.6
作者：
Goncharuk, V. V.;Bagrii, V. A.;Bashtan, S. Yu
通讯作者：
Bashtan, S. Yu
DOI：
10.1073/pnas.1417392112
发表时间：
2015-03
期刊：
Proceedings of the National Academy of Sciences
影响因子：
--
作者：
A. Paytan;A. Lecher;N. Dimova;K. Sparrow;F. G. Kodovska;Joseph Murray;S. Tulaczyk;J. Kessler
通讯作者：
A. Paytan;A. Lecher;N. Dimova;K. Sparrow;F. G. Kodovska;Joseph Murray;S. Tulaczyk;J. Kessler
使用铂微电极连续多次测量土壤氧化还原电位
影响因子：
2.9
作者：
E. Bochove;S. Beauchemin;G. Thériault
通讯作者：
G. Thériault
DOI：
10.2136/sssaj1987.03615995005100050019x
发表时间：
1987-09-01
影响因子：
2.9
作者：
PARKIN, TB
通讯作者：
PARKIN, TB