@article {2667,
	title = {Sources and radiocarbon ages of organic carbon in different grain size fractions of Yellow River-transported particles and coastal sediments},
	journal = {Chemical Geology},
	volume = {534},
	year = {2020},
	month = {Jan-02-2020},
	pages = {119452},
	keywords = {organic matter, RadiocarbonStable carbon isotope, Sediment grain size, Yellow River},
	issn = {00092541},
	doi = {10.1016/j.chemgeo.2019.119452},
	url = {https://www.sciencedirect.com/science/article/pii/S0009254119305819},
	author = {Ge, Tiantian and Xue, Yuejun and Jiang, Xueyan and Zou, Li and Wang, Xuchen}
}
@article {2616,
	title = {Large Variability of Dissolved Inorganic Radiocarbon in the Kuroshio Extension of the Northwest North PacificABSTRACT},
	journal = {Radiocarbon},
	volume = {60264317255},
	year = {2018},
	month = {Jan-04-2018},
	pages = {691 - 704},
	abstract = {Radiocarbon (C-14) in dissolved inorganic carbon (DIC) was measured for water samples collected from six deep stations in the Kuroshio Extension (KE) region in the northwestern North Pacific in April-May 2015. Vertical profiles of Delta C-14-DIC indicate that bomb-produced Delta
C-14 was present from the surface to similar to 1500 m water depth. Large variations in Delta C-14-DIC values (300 parts per thousand) were
observed at 500 m water depth among the stations and the differences were likely controlled by transport and mixing dynamics of different
water masses in the region. The major Pacific western boundary currents, such as Kuroshio and Oyashio and regional mesoscale eddies, could play important roles affecting the observed Delta C-14-DIC variability. The depth profiles of both Delta C-14-DIC and DIC concentrations can be predicted by the solution mixing model and can be used as conservative tracers of water mass movement and water parcel homogenization in the
ocean.},
	keywords = {bomb radiocarbon, carbon, intermediate water, MIXED WATER REGION, ocean, WESTERN BOUNDARY CURRENTS},
	issn = {0033-8222},
	doi = {10.1017/RDC.2017.143},
	url = {https://www.cambridge.org/core/product/identifier/S0033822217001436/type/journal_articlehttps://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0033822217001436},
	author = {Ding, Ling and Ge, Tiantian and Gao, Huiwang and Luo, Chunle and Xue, Yuejun and Druffel, Ellen R M and Wang, Xuchen}
}
@article {2527,
	title = {Mobilization and export of millennial-aged organic carbon by the Yellow River},
	journal = {Limnology and Oceanography},
	year = {2017},
	month = {Jan-04-2017},
	abstract = {A combined carbon isotope (13C and 14C) study was carried out to investigate the sources and fate of organic carbon (OC) transported by the Yellow River and preserved in the sediments of the Bohai and Yellow Seas. In 2015, the Yellow River delivered 3.14 {\texttimes} 1010 g C and 4.12 {\texttimes} 1010 g C of dissolved organic carbon (DOC) and particulate organic carbon (POC) to the Bohai Sea. Carbon isotope signatures revealed that the Yellow River transports millennial-aged DOC and POC during all seasons. The values of δ13C-DOC ranged from -24.7{\textperthousand} to -28.8{\textperthousand} in the river basin, and -21.0{\textperthousand} to -27.0{\textperthousand} in the lower reach. The 14C ages of DOC were 415{\textendash}1690 yr before present (BP) in the river basin, and they were relatively constant seasonally (1320{\textendash}1690 yr BP) in the lower reach of the river. In comparison, POC δ13C values in the river were less variable (-22.8{\textperthousand} to -25.0{\textperthousand}), but much older in both the river basin (4960 {\textpm} 1690 yr BP) and in the lower reach (4040 {\textpm} 1050 yr BP). Calculations using a dual-isotopic three-end member model revealed that biomass OC derived from C3 plants was the major source of riverine DOC, contributing 65\% {\textpm} 8\% and 52\% {\textpm} 2\% in the river basin and lower reach seasonally. Pre-aged soil OC and fossil OC from weathering contributed 21{\textendash}42\% and 6{\textendash}14\% of the DOC, respectively. In contrast, pre-aged soil OC and fossil OC contributed 60{\textendash}70\% and 17{\textendash}27\% of POC, and biomass OC contributed a minor fraction (13\% {\textpm} 7\%) of riverine POC. Our results further revealed that aged riverine POC had a major influence on OC preservation in the delta and coastal sediments of the Bohai and Yellow Seas. The age of OC in surface sediments varied widely (1610{\textendash}8275 yr) due to the influence of Yellow River input. Pre-aged soil OC and fossil OC each contributed 32\% {\textpm} 8\% and 22\% {\textpm} 14\% of OC preserved in the sediments. We estimate that about 0.27 Mt yr-1 and 0.07 Mt yr-1 of pre-aged soil OC and fossil OC accumulate in the surface sediments from POC delivered by the modern Yellow River, and 0.013 Mt yr-1 and 0.002 Mt yr-1 of pre-aged soil OC and fossil OC enters the coastal DOC cycle from riverine DOC. The millennial-aged OC delivered to coastal seas by the Yellow River therefore has profound impacts not only on carbon cycling and the carbon budget in the marginal sea, but also on coastal ecosystems and biogeochemical processes.},
	doi = {10.1002/lno.10579},
	url = {http://doi.wiley.com/10.1002/lno.10579http://onlinelibrary.wiley.com/wol1/doi/10.1002/lno.10579/fullpdfhttps://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002\%2Flno.10579},
	author = {Xue, Yuejun and Zou, Li and Ge, Tiantian and Wang, Xuchen}
}
@article { ISI:000375679100005,
	title = {Carbon isotopic (C-14 and C-13) characterization of fossil-fuel derived dissolved organic carbon in wet precipitation in Shandong Province, China},
	journal = {JOURNAL OF ATMOSPHERIC CHEMISTRY},
	volume = {73},
	number = {{2}},
	year = {2016},
	month = {JUN},
	pages = {207-221},
	type = {Article},
	abstract = {We present results from a 1-year study of radiocarbon and stable carbon isotope measurement of dissolved organic carbon (DOC) of wet precipitation samples collected in the Shandong province of China. A total of 32 rainfall and 4 snow samples were collected from two coastal cities (Qingdao and Yantai) and one inland site (Taian) during 2014. Concentrations of DOC in the rainwater and snow samples varied widely from 28 to 616 mu M. In general, rainwater originating from marine sources had relatively low DOC concentrations compared with continentally generated precipitation. Values of delta C-13-DOC and Delta C-14-DOC in the snow and rainwater ranged from -19.0 to -29.4 \% and -23 to -494 \%, with corresponding radiocarbon ages of 125 to 5410 years before present. The dominant DOC in the wet precipitation had a relatively old C-14 age (average 2841 years) and a depleted C-13 value (average -24.4 Years), indicating the mixing of contemporary organic carbon with C-14-depleted fossil fuel-derived soluble organic carbon in the atmosphere. Using a dual isotopic two-endmember model, we calculate that 7 \% to 52 \% of DOC in the snow and rainfall originated from fossil fuels. It is estimated that the flux of DOC in continental rainfall of China is 23 x 10(12) g C yr(-1) and of this, 7.1 x 10(12) g C yr(-1) could be fossil-fuel OC. On a global scale, the DOC flux in rainfall is estimated to be 357 Tg C yr(-1), and 110 Tg C yr(-1) could be fossil fuel-derived. Our study demonstrates that wet precipitation is an important removal process for old fossil fuel carbon from the atmosphere. This removal mechanism could play an important role in the carbon cycle, especially for the anthropogenically derived fraction, and it should be taken into consideration in global carbon cycle models.},
	keywords = {Atmospheric pollution, Fossil fuelemission, organic carbon, radiocarbon, Wet precipitation},
	issn = {0167-7764},
	doi = {10.1007/s10874-015-9323-3},
	author = {Wang, Xuchen and Ge, Tiantian and Xu, Caili and Xue, Yuejun and Luo, Chunle}
}
@article { ISI:000383622900016,
	title = {Controls on the sources and cycling of dissolved inorganic carbon in the Changjiang and Huanghe River estuaries, China: C-14 and C-13 studies},
	journal = {LIMNOLOGY AND OCEANOGRAPHY},
	volume = {61},
	number = {{4}},
	year = {2016},
	month = {JUL},
	pages = {1358-1374},
	type = {Article},
	abstract = {The Changjiang (Yangtze River) and Huanghe (Yellow River) are the two largest rivers in China, and they transport large amounts of terrestrial carbon to the coastal waters of the East China Sea and the Bohai Sea. The sources and cycling of riverine carbon in these two large river estuaries, however, have not been well studied. In this article, we present the results of dual isotope (Delta C-14 and delta C-13) measurements of dissolved inorganic carbon (DIC) collected in the low reaches of the Changjiang and Huanghe and their estuaries during two cruises in 2014. Our results indicate that both the Changjiang and Huanghe carry very high concentrations of DIC ranging from 1384 mu mol kg(-1) to 1732 mu mol kg(-1) and 2711 mu mol kg(-1) to 4120 mu mol kg(-1), respectively, and DIC levels varied with flow rates during high and low discharge periods. The cycling of DIC exhibited conservative behavior in both the Changjiang and Huanghe estuaries, suggesting DIC levels were controlled mainly by physical mixing processes. Delta C-14-DIC values indicate that the Changjiang and Huanghe transport aged DIC (1060-1380 yr old). Both Delta C-14-DIC and delta C-13-DIC values also showed conservative mixing in the two estuaries. Using a dual carbon isotopic model, we calculated that atmospheric CO2 consumed mainly by silicate weathering was a major source, contributing 65.2 +/- 9.0\% and 73.4 +/- 3.0\% of DIC in the Changjiang and Huanghe, and 96.9-97.7\% (by air-sea exchange) of DIC in the coastal waters of the East China Sea (ECS) and Bohai Sea, respectively. Our results indicate that carbonate dissolution was an important (12.3-17.4\%) but not major process controlling the high DIC levels in both rivers, as suggested previously. Compared with the large Amazon River, respiration of riverine organic matter (OM) played a less important role, contributing only 15.4-17.2\% of DIC in the two Asian rivers. Flux calculations indicate that the Changjiang and Huanghe discharged 1.46 x 10(13) g and 6.28 x 10(11) g DIC into the ECS and Bohai Sea in 2014, which were 9 and 17 times higher than the DOC fluxes in the two rivers. These large fluxes of riverine DIC, especially of aged DIC, could have significant impacts on primary production and carbon cycling in the ECS and Bohai Sea.},
	issn = {0024-3590},
	doi = {10.1002/lno.10301},
	author = {Wang, Xuchen and Luo, Chunle and Ge, Tiantian and Xu, Caili and Xue, Yuejun}
}
@article { ISI:000389875700006,
	title = {DISSOLVED INORGANIC RADIOCARBON IN THE NORTHWEST PACIFIC CONTINENTAL MARGIN},
	journal = {RADIOCARBON},
	volume = {58},
	number = {{3}},
	year = {2016},
	month = {SEP},
	pages = {517-529},
	type = {Article},
	abstract = {This article presents a modified method for extraction of dissolved inorganic carbon (DIC) from seawater for radiocarbon measurement by accelerator mass spectrometry (AMS). Standard tests indicate that the extraction efficiencies of DIC are >96\%, and the respective precisions of. Delta C-14-DIC and delta C-13-DIC analyses are 6\% and 0.1\% or better. Using the method, we report. Delta C-14-DIC profiles collected from the shelf and slope in the East China Sea (ECS) of the northwest Pacific Ocean. Both the DIC concentration and. Delta C-14-DIC in the shelf and slope regions seem primarily affected by the Kuroshio Current. It is estimated that 54-65\% of the bottom water in the shelf region could be from the intrusion of Kuroshio intermediate water, which carries a high concentration and low. Delta C-14 values of DIC, and which influenced the DIC and its Delta C-14 signature on the shelf. Compared with the. Delta C-14-DIC profiles at other sites in the northwest Pacific reported previously, it appears that the. Delta C-14-DIC distributions are mainly controlled by the major oceanic currents in the region, and large variations in. Delta C-14-DIC occurred mostly in the upper 800m of the water column. The similarity of. Delta C-14-DIC at depth suggests that the deep-water circulation patterns have been relatively stable in the northwest Pacific Ocean in the last 20 yr.},
	keywords = {continental margin, dissolved inorganic carbon, East China Sea, radiocarbon, stable carbon isotope},
	issn = {0033-8222},
	doi = {10.1017/RDC.2016.23},
	author = {Ge, Tiantian and Wang, Xuchen and Zhang, Jing and Luo, Chunle and Xue, Yuejun}
}
@article { ISI:000392927300002,
	title = {Two black carbon pools transported by the Changjiang and Huanghe Rivers in China},
	journal = {GLOBAL BIOGEOCHEMICAL CYCLES},
	volume = {30},
	number = {{12}},
	year = {2016},
	month = {DEC},
	pages = {1778-1790},
	type = {Article},
	abstract = {Major rivers play important roles in transporting large amounts of terrestrial organic matter from land to the ocean each year, and the organic matter carried by rivers contains a significant fraction of black carbon (BC). A recent study estimated that 0.027 Gt of BC is transported in the dissolved phase by rivers each year, which accounts for similar to 10\% of the global flux of dissolved organic carbon. The relative sources of this large amount of riverine dissolved black carbon (DBC) from biomass burning (young, modern C-14) and fossil fuel (old, C-14 free) combustion are not known. We present radiocarbon measurements of BC in both dissolved and particulate phases transported by the Changjiang and Huanghe Rivers, the two largest rivers in China, during 2015. We show that two, distinct BC pools (young and old) were carried by the rivers. The DBC pool was much younger than the particulate BC (PBC) pool. Mass balance calculations indicate that most (78-85\%) of the DBC in the Changjiang and Huanghe Rivers was derived from biomass burning, and only 15-22\% was from fossil fuel combustion. In contrast, PBC from biomass burning and fossil fuel combustion were approximately equal in these two rivers. Export of PBC and DBC by the rivers are decoupled, and fluxes of PBC were 4.1 and 6.7 times higher than DBC in the Changjiang and Huanghe Rivers, respectively. The C-14 age differences of the two BC pools suggest that BC derived from biomass burning and fossil fuel combustion are mobilized in different phases and on different time scales in these rivers.},
	issn = {0886-6236},
	doi = {10.1002/2016GB005509},
	author = {Wang, Xuchen and Xu, Caili and Druffel, Ellen M. and Xue, Yuejun and Qi, Yuanzhi}
}
