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DOI	10.1038/s41561-020-0571-8
	Significant methane ebullition from alpine permafrost rivers on the East Qinghai–Tibet Plateau
	Zhang L.; Xia X.; Liu S.; Zhang S.; Li S.; Wang J.; Wang G.; Gao H.; Zhang Z.; Wang Q.; Wen W.; Liu R.; Yang Z.; Stanley E.H.; Raymond P.A.
发表日期	2020
ISSN	17520894
起始页码	349
结束页码	354
卷号	13 期号:5
英文摘要	Inland waters are large sources of methane to the atmosphere. However, considerable uncertainty exists in estimating the emissions of this potent greenhouse gas from global streams and rivers due, in part, to a lack of direct measurements in the high-altitude cryosphere and poor accounting for ebullition. Here we present methane concentrations and fluxes over three years in four basins on the East Qinghai–Tibet Plateau. Methane ebullition rates decrease exponentially whereas diffusion declines linearly with increasing stream order. Nonetheless, the average ebullition rate (11.9 mmolCH4 m−2 d−1) from these streams and rivers—which have large organic stocks in surrounding permafrost, abundant cold-tolerant methanogens, shallow water depths, and experience low air pressure—were six times greater than the global average and reached a maximum of 374.4 mmolCH4 m−2 d−1. Upscaled total emissions from sampled third- to seventh-order waterways of the East Qinghai–Tibet Plateau are estimated to be 0.20 TgCH4 yr−1, 79% of which was attributed to ebullition. These methane emissions are approximately 20% of CO2 emissions (2.70 TgCO2 yr−1) in terms of carbon release and two times greater in terms of CO2-equivalent emissions. When upscaled to first- to seventh-order waterways, we estimate emissions of 0.37–1.23 TgCH4 yr−1. Our findings demonstrate that high-elevation rivers on the Qinghai–Tibet Plateau are hotspots of methane delivery to the atmosphere. The large ebullitive fluxes, which constitute a substantial fraction of global fluvial methane emissions, reveal a positive feedback between climate warming, permafrost thaw and methane emissions. © 2020, The Author(s), under exclusive licence to Springer Nature Limited.
英文关键词	air-water interaction; carbon dioxide; carbon emission; concentration (composition); cryosphere; greenhouse gas; methane; permafrost; China; Qinghai-Xizang Plateau
语种	英语
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/206844
作者单位	Key Laboratory of Water and Sediment Sciences of Ministry of Education and State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China; School of Forestry and Environmental Studies, Yale University, New Haven, CT, United States; Department of Mathematics, Hong Kong Baptist University, Hong Kong; Center for Limnology, University of Wisconsin–Madison, Madison, WI, United States
推荐引用方式 GB/T 7714	Zhang L.,Xia X.,Liu S.,等. Significant methane ebullition from alpine permafrost rivers on the East Qinghai–Tibet Plateau[J],2020,13(5).
APA	Zhang L..,Xia X..,Liu S..,Zhang S..,Li S..,...&Raymond P.A..(2020).Significant methane ebullition from alpine permafrost rivers on the East Qinghai–Tibet Plateau.Nature Geoscience,13(5).
MLA	Zhang L.,et al."Significant methane ebullition from alpine permafrost rivers on the East Qinghai–Tibet Plateau".Nature Geoscience 13.5(2020).