气候变化领域集成服务门户(CCPortal): Using radon to quantify groundwater discharge and methane fluxes to a shallow, tundra lake on the Yukon-Kuskokwim Delta, Alaska

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DOI	10.1007/s10533-020-00647-w
	Using radon to quantify groundwater discharge and methane fluxes to a shallow, tundra lake on the Yukon-Kuskokwim Delta, Alaska
	Dabrowski J.S.; Charette M.A.; Mann P.J.; Ludwig S.M.; Natali S.M.; Holmes R.M.; Schade J.D.; Powell M.; Henderson P.B.
发表日期	2020
ISSN	1682563
英文摘要	Northern lakes are a source of greenhouse gases to the atmosphere and contribute substantially to the global carbon budget. However, the sources of methane (CH4) to northern lakes are poorly constrained limiting our ability to the assess impacts of future Arctic change. Here we present measurements of the natural groundwater tracer, radon, and CH4 in a shallow lake on the Yukon-Kuskokwim Delta, AK and quantify groundwater discharge rates and fluxes of groundwater-derived CH4. We found that groundwater was significantly enriched (2000%) in radon and CH4 relative to lake water. Using a mass balance approach, we calculated average groundwater fluxes of 1.2 ± 0.6 and 4.3 ± 2.0 cm day−1, respectively as conservative and upper limit estimates. Groundwater CH4 fluxes were 7—24 mmol m−2 day−1 and significantly exceeded diffusive air–water CH4 fluxes (1.3–2.3 mmol m−2 day−1) from the lake to the atmosphere, suggesting that groundwater is an important source of CH4 to Arctic lakes and may drive observed CH4 emissions. Isotopic signatures of CH4 were depleted in groundwaters, consistent with microbial production. Higher methane concentrations in groundwater compared to other high latitude lakes were likely the source of the comparatively higher CH4 diffusive fluxes, as compared to those reported previously in high latitude lakes. These findings indicate that deltaic lakes across warmer permafrost regions may act as important hotspots for CH4 release across Arctic landscapes. © 2020, Springer Nature Switzerland AG.
英文关键词	Groundwater; Methane; Radon-222; Subarctic; Tundra; Wetland
语种	英语
来源期刊	Biogeochemistry
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/120387
作者单位	Department of Earth and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, United States; Department of Marine Chemistry & Geochemistry, Woods Hole Oceanographic Institution, 266 Woods Hole Road, MS#25, Woods Hole, MA 02543, United States; Department of Geography & Environmental Sciences, Northumbria University, Newcastle Upon Tyne, NE1 8ST, United Kingdom; Department of Earth & Environmental Sciences, Columbia University, 61 Rt. 9W, 207E Oceanography, Palisades, NY 10964, United States; Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540, United States; Department of Earth and Planetary Sciences, Harvard University, 20 Oxford St, Cambridge, MA 02138, United States
推荐引用方式 GB/T 7714	Dabrowski J.S.,Charette M.A.,Mann P.J.,et al. Using radon to quantify groundwater discharge and methane fluxes to a shallow, tundra lake on the Yukon-Kuskokwim Delta, Alaska[J],2020.
APA	Dabrowski J.S..,Charette M.A..,Mann P.J..,Ludwig S.M..,Natali S.M..,...&Henderson P.B..(2020).Using radon to quantify groundwater discharge and methane fluxes to a shallow, tundra lake on the Yukon-Kuskokwim Delta, Alaska.Biogeochemistry.
MLA	Dabrowski J.S.,et al."Using radon to quantify groundwater discharge and methane fluxes to a shallow, tundra lake on the Yukon-Kuskokwim Delta, Alaska".Biogeochemistry (2020).