Riverine export of water, sediment and carbon during flood events in the arid to semi-arid Wuding River on the Chinese Loess Plateau

doi:10.1002/esp.4845

	Riverine export of water, sediment and carbon during flood events in the arid to semi-arid Wuding River on the Chinese Loess Plateau
	Ran, Lishan 3; Yang, Xiankun 4; Tian, Mingyang 4; Shi, Hongyan 1; Liu, Shaoda 5; Yu, Ruihong 1; Zhou, Yuanyuan 2
刊名	EARTH SURFACE PROCESSES AND LANDFORMS
	2020-06-30
卷号	45 期号:8 页码:1777-1788
关键词	water and sediment carbon export CO(2)degassing floods Wuding River catchment
ISSN号	0197-9337
DOI	10.1002/esp.4845
通讯作者	Ran, Lishan(lsran@hku.hk)
英文摘要	Floods have become increasingly important in fluvial export of water, sediment and carbon (C). Using high-frequency sampling, the export of water, sediment and C was examined in the Wuding River catchment on the Chinese Loess Plateau. With groundwater as an important contributor to runoff all year round, floods were relatively less important in the export of water. However, large floods were disproportionately important in exporting sediment and inorganic C (DIC) and organic C (DOC and POC). The three largest floods in each year transported 53.6-97.3 and 41.4-77% of the annual sediment and C fluxes, respectively. An extreme flood in 2017 alone contributed 94.6 and 73.1% of the annual sediment and C fluxes, respectively, in just 7 days, which included 20.3, 92.1 and 35.7% of the annual DOC, POC and DIC fluxes, respectively. A stable carbon isotope (delta C-13) analysis of POC indicated that modern soils and C3 plants were its primary source. Furthermore, floods greatly accelerated CO(2)degassing due to elevated gas transfer velocity, although stream water CO(2)partial pressure (pCO(2)) exhibited a decreasing trend with flow discharge. Although these results illustrated that increasing runoff dilutedpCO(2), the timing and magnitude of floods were found to be critical in determining the response ofpCO(2)to flow dynamics. Low-magnitude floods in the early wet season increasedpCO(2)because of enhanced organic matter input, while subsequent large floods caused a lowerpCO(2)due to greatly reduced organic matter supply. Finally, continuous monitoring of a complete flood event showed that the CO(2)efflux during the flood (2348 +/- 664 mg C m(-2) day(-1)) was three times that under low-flow conditions (808 +/- 98 mg C m(-2) day(-1)). Our study suggests that infrequent, heavy storm events, which are predicted to increase under climate change, will greatly alter the transport regimes of sediment and C. (c) 2020 John Wiley & Sons, Ltd.
WOS关键词	ORGANIC-CARBON ; YELLOW-RIVER ; CLIMATE-CHANGE ; CO2 EVASION ; CATCHMENT ; TRANSPORT ; PARTICULATE ; RUNOFF ; SYSTEM ; IMPACT
WOS研究方向	Physical Geography ; Geology
语种	英语
出版者	WILEY
WOS记录号	WOS:000540134800007
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/162188]
专题	中国科学院地理科学与资源研究所
通讯作者	Ran, Lishan
作者单位	1.Inner Mongolia Univ, Sch Ecol & Environm, Hohhot, Peoples R China 2.Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China 3.Univ Hong Kong, Dept Geog, Pokfulam Rd, Hong Kong, Peoples R China 4.Guangzhou Univ, Sch Geog Sci, Guangzhou, Peoples R China 5.Yale Sch Forestry & Environm Studies, New Haven, CT USA
推荐引用方式 GB/T 7714	Ran, Lishan,Yang, Xiankun,Tian, Mingyang,et al. Riverine export of water, sediment and carbon during flood events in the arid to semi-arid Wuding River on the Chinese Loess Plateau[J]. EARTH SURFACE PROCESSES AND LANDFORMS,2020,45(8):1777-1788.
APA	Ran, Lishan.,Yang, Xiankun.,Tian, Mingyang.,Shi, Hongyan.,Liu, Shaoda.,...&Zhou, Yuanyuan.(2020).Riverine export of water, sediment and carbon during flood events in the arid to semi-arid Wuding River on the Chinese Loess Plateau.EARTH SURFACE PROCESSES AND LANDFORMS,45(8),1777-1788.
MLA	Ran, Lishan,et al."Riverine export of water, sediment and carbon during flood events in the arid to semi-arid Wuding River on the Chinese Loess Plateau".EARTH SURFACE PROCESSES AND LANDFORMS 45.8(2020):1777-1788.