气候变化领域集成服务门户(CCPortal): Photochemical Mineralization of Terrigenous DOC to Dissolved Inorganic Carbon in Ocean

CCPortal

DOI	10.1002/2017GB005698
	Photochemical Mineralization of Terrigenous DOC to Dissolved Inorganic Carbon in Ocean
	Aarnos H.; Gélinas Y.; Kasurinen V.; Gu Y.; Puupponen V.-M.; Vähätalo A.V.
发表日期	2018
ISSN	0886-6236
EISSN	1944-9224
起始页码	250
结束页码	266
卷号	32 期号:2
英文摘要	When terrigenous dissolved organic carbon (tDOC) rich in chromophoric dissolved organic matter (tCDOM) enters the ocean, solar radiation mineralizes it partially into dissolved inorganic carbon (DIC). This study addresses the amount and the rates of DIC photoproduction from tDOC and the area of ocean required to photomineralize tDOC. We collected water samples from 10 major rivers, mixed them with artificial seawater, and irradiated them with simulated solar radiation to measure DIC photoproduction and the photobleaching of tCDOM. The linear relationship between DIC photoproduction and tCDOM photobleaching was used to estimate the amount of photoproduced DIC from the tCDOM fluxes of the study rivers. Solar radiation was estimated to mineralize 12.5 ± 3.7 Tg C yr−1 (10 rivers)−1 or 18 ± 8% of tDOC flux. The irradiation experiments also approximated typical apparent spectral quantum yields for DIC photoproduction (ϕλ) over the entire lifetime of the tCDOM. Based on ϕλs and the local solar irradiances in river plumes, the annual areal DIC photoproduction rates from tDOC were calculated to range from 52 ± 4 (Lena River) to 157 ± 2 mmol C m−2 yr−1 (Mississippi River). When the amount of photoproduced DIC was divided by the areal rate, 9.6 ± 2.5 × 106 km2 of ocean was required for the photomineralization of tDOC from the study rivers. Extrapolation to the global tDOC flux yields 45 (31–58) Tg of photoproduced DIC per year in the river plumes that cover 34 (25–43) × 106 km2 of the ocean. ©2018. American Geophysical Union. All Rights Reserved.
英文关键词	carbon; CDOM; DOC; ocean; photochemistry; rivers
语种	英语
scopus关键词	bleaching; carbon flux; dissolved inorganic carbon; dissolved organic carbon; global ocean; irradiation; mineralization; photochemistry; river plume; river water; solar radiation; Lena River; Mississippi River; Russian Federation; United States
来源期刊	Global Biogeochemical Cycles
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/129859
作者单位	Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland; Department of Environmental Sciences, University of Helsinki, Helsinki, Finland; Geotop, Montreal, QC, Canada; Department of Chemistry and Biochemistry, Concordia University, Montreal, QC, Canada; Department of Forest Sciences, University of Helsinki, Helsinki, Finland; Department of Physics, University of Helsinki, Helsinki, Finland; Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
推荐引用方式 GB/T 7714	Aarnos H.,Gélinas Y.,Kasurinen V.,et al. Photochemical Mineralization of Terrigenous DOC to Dissolved Inorganic Carbon in Ocean[J],2018,32(2).
APA	Aarnos H.,Gélinas Y.,Kasurinen V.,Gu Y.,Puupponen V.-M.,&Vähätalo A.V..(2018).Photochemical Mineralization of Terrigenous DOC to Dissolved Inorganic Carbon in Ocean.Global Biogeochemical Cycles,32(2).
MLA	Aarnos H.,et al."Photochemical Mineralization of Terrigenous DOC to Dissolved Inorganic Carbon in Ocean".Global Biogeochemical Cycles 32.2(2018).