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DOI	10.1088/1748-9326/ab83ac
	Warming and monsoonal climate lead to large export of millennial-aged carbon from permafrost catchments of the Qinghai-Tibet Plateau
	Song C.; Wang G.; Haghipour N.; Raymond P.A.
发表日期	2020
ISSN	17489318
卷号	15 期号:7
英文摘要	Permafrost carbon pool destabilization causes substantial fluvial export of soil carbon, yet the export patterns and magnitudes are not well understood. Here we investigated the radiocarbon (14C) in dissolved organic and inorganic carbon (DOC and DIC, respectively) exported from a mid-sized river in the central Qinghai-Tibet Plateau (QTP) permafrost region. We utilized the radiocarbon dating technique to reveal the ages of riverine dissolved carbon and a statistical model to partition the riverine carbon from different age categories. DOC and DIC showed bomb-depleted 14C signatures corresponding to millennial ages. Seasonally, 14C-depleted DOC and DIC ages were associated with active layer thaw and flow path deepening. Spatially, older DOC and DIC were found in the valley sites correlated with warmer permafrost and higher groundwater flow. Further, isotopic mixing models suggested that 83 ± 27% of riverine DOC was derived from active layer and permafrost layer aged carbon. DIC export was comprised of a smaller portion of aged carbon (47.3 ± 2.6%) but a much larger flux of aged carbon due to higher annual DIC export. Interestingly, approximately 56% of annual aged DOC and DIC were exported in the short summer season (July to September). The monsoon climate-induced overlap of high discharge and maximum active layer thaw depth in summer enhanced the remarkably rapid fluvial export of millennial-aged carbon. Annual aged carbon yields in YRSR (275 ± 90 and 1661 ± 91 kg km-2 yr-1 for DOC and DIC, respectively) are much larger than those of Kolyma River (160 ± 89 and 234 ± 105 kg km-2 yr-1 for DOC and DIC, respectively). These results suggest a unique old carbon loss pattern in the QTP permafrost region compared to higher latitude permafrost regions with a non-monsoonal climate. As climate warms, more old carbon export is expected, which may affect the permafrost carbon pool and the river biogeochemical processes. © 2020 The Author(s). Published by IOP Publishing Ltd.
英文关键词	climate warming; permafrost; Qinghai-Tibet Plateau river; radiocarbon; riverine carbon export; stable carbon isotope
语种	英语
scopus关键词	Carbon; Catchments; Forestry; Groundwater; Groundwater flow; Permafrost; Rivers; Thawing; Biogeochemical process; Dissolved carbons; Dissolved organic and inorganic carbon; Higher latitudes; Permafrost region; Qinghai Tibet plateau; Radiocarbon dating; Statistical modeling; Organic carbon; active layer; catchment; groundwater flow; monsoon; permafrost; radiocarbon dating; soil carbon; China; Kolyma River; Qinghai-Xizang Plateau; Russian Federation
来源期刊	Environmental Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/153976
作者单位	Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, Sichuan, China; State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource and Hydropower, Sichuan University, Chengdu, Sichuan, China; Geological Institute, Department of Earth Sciences, ETH Zürich, Sonneggstrasse 5, Zürich, 8092, Switzerland; Laboratory of Ion Beam Physics, ETHZ, Otto-Stern-Weg 5, Zurich, 8093, Switzerland; School of Forestry and Environmental Studies, Yale University, New Haven, CT, United States
推荐引用方式 GB/T 7714	Song C.,Wang G.,Haghipour N.,et al. Warming and monsoonal climate lead to large export of millennial-aged carbon from permafrost catchments of the Qinghai-Tibet Plateau[J],2020,15(7).
APA	Song C.,Wang G.,Haghipour N.,&Raymond P.A..(2020).Warming and monsoonal climate lead to large export of millennial-aged carbon from permafrost catchments of the Qinghai-Tibet Plateau.Environmental Research Letters,15(7).
MLA	Song C.,et al."Warming and monsoonal climate lead to large export of millennial-aged carbon from permafrost catchments of the Qinghai-Tibet Plateau".Environmental Research Letters 15.7(2020).