Riverine CO2 supersaturation and outgassing in a subtropical monsoonal mountainous area (Three Gorges Reservoir Region) of China

doi:10.1016/j.jhydrol.2018.01.057

CORC > 重庆绿色智能技术研究院 > 中国科学院重庆绿色智能技术研究院 > 生态过程与重建研究中心

	Riverine CO2 supersaturation and outgassing in a subtropical monsoonal mountainous area (Three Gorges Reservoir Region) of China
	Li, Siyue1 ; Ni, Maofei 1,2; Mao, Rong 1; Bush, Richard T.3
刊名	JOURNAL OF HYDROLOGY
	2018-03-01
卷号	558 页码:460-469
关键词	Riverine carbon flux CO2 degassing Partial pressure of CO2 Dissolved inorganic carbon Mountainous streams and rivers Three Gorges Reservoir catchment
ISSN号	0022-1694
DOI	10.1016/j.jhydrol.2018.01.057
英文摘要	Rivers are an important source of CO2 to the atmosphere, however, mountainous rivers and streams with high emission rates are not well studied particularly in China. We report the first detailed investigation on monsoonal mountainous rivers in the Three Gorges Reservoir (TGR) region, with a focus on the riverine CO2 partial pressure (pCO(2)), CO2 degassing and their potential controls. The pCO(2) levels ranged from 50 to 6019 mu atm with averages of 1573 (SD. +/- 1060) in dry Autumn and 1276 (SD. +/- 1166) mu atm in wet Summer seasons. 94% of samples were supersaturated with CO2 with respect to the atmospheric equilibrium (410 mu atm). Monsoonal precipitation controlled pCO(2) seasonality, with both the maximal and minimal levels occurring in the wet season, and showing the overall effects of dilution. Riverine pCO(2) could be predicted better in the dry season using pH, DO% and DTP, whereas pH and DOC were better predictors in the wet season. We conclude that in-situ respiration of allochthonous organic carbon, rather than photosynthesis, resulted in negative relationships between pCO(2) and DO and pH, and thus CO2 supersaturation. Photosynthetic primary production was effectively limited by rapid flow velocity and short residence time. The estimated water-to-air CO2 emission rate in the TGR rivers was 350 319 in the Autumn and lower, yet more variable at 326 439 mmol/m(2)/d in Summer. Our calculated CO2 areal fluxes were in the upper-level magnitude of published data, demonstrating the importance of mountainous rivers and streams as a global greenhouse gas source, and urgency for more detailed studies on CO2 degassing, to address a global data gap for these environments. (C) 2018 Elsevier B.V. All rights reserved.
资助项目	Chinese Academy of Sciences, China[R53A362Z10] ; National Natural Science Foundation of China, China (NSFC)[31670473]
WOS研究方向	Engineering ; Geology ; Water Resources
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000427338900037
内容类型	期刊论文
源URL	[http://119.78.100.138/handle/2HOD01W0/6293]
专题	生态过程与重建研究中心
通讯作者	Li, Siyue
作者单位	1.Chinese Acad Sci, Chongqing Inst Green & Intelligent Technol, 266 Fangzheng Ave,Shuitu High Tech Pk, Chongqing 400714, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Univ Newcastle, Newcastle Inst Energy & Resources, Int Ctr Balanced Land Use, Callaghan, NSW 2308, Australia
推荐引用方式 GB/T 7714	Li, Siyue,Ni, Maofei,Mao, Rong,et al. Riverine CO2 supersaturation and outgassing in a subtropical monsoonal mountainous area (Three Gorges Reservoir Region) of China[J]. JOURNAL OF HYDROLOGY,2018,558:460-469.
APA	Li, Siyue,Ni, Maofei,Mao, Rong,&Bush, Richard T..(2018).Riverine CO2 supersaturation and outgassing in a subtropical monsoonal mountainous area (Three Gorges Reservoir Region) of China.JOURNAL OF HYDROLOGY,558,460-469.
MLA	Li, Siyue,et al."Riverine CO2 supersaturation and outgassing in a subtropical monsoonal mountainous area (Three Gorges Reservoir Region) of China".JOURNAL OF HYDROLOGY 558(2018):460-469.