scholarly journals Scaling effects of a eutrophic river plume on organic carbon consumption

2021 ◽  
Author(s):  
Chung‐Chi Chen ◽  
Gwo‐Ching Gong ◽  
Kuo‐Ping Chiang ◽  
Fuh‐Kwo Shiah ◽  
Chih‐Ching Chung ◽  
...  
Keyword(s):  
Organic Carbon ◽  
River Plume ◽  
Scaling Effects ◽  
Carbon Consumption ◽  
Eutrophic River

Kinetics of Organic Carbon Consumption by Yeast Strain UY7

2011 ◽  
Vol 47 (1) ◽  
pp. 1-7
Author(s):  
WATARU TAKATSUJI ◽  
YOSHINOBU YAMAGIWA ◽  
KENJI FURUKAWA
Keyword(s):  
Organic Carbon ◽  
Yeast Strain ◽  
Carbon Consumption ◽  
Kinetics Of

scholarly journals The large variation in organic carbon consumption in spring in the East China Sea

2013 ◽  
Vol 10 (5) ◽  
pp. 2931-2943 ◽  
Author(s):  
C.-C. Chen ◽  
G.-C. Gong ◽  
F.-K. Shiah ◽  
W.-C. Chou ◽  
C.-C. Hung
Keyword(s):  
Low Temperature ◽  
Organic Carbon ◽  
East China Sea ◽  
Phytoplankton Growth ◽  
East China ◽  
Changjiang River ◽  
Carbon Consumption ◽  
The East China Sea ◽  
China Sea ◽  
The Changjiang River

Abstract. A tremendous amount of organic carbon respired by plankton communities has been found in summer in the East China Sea (ECS), and this rate has been significantly correlated with fluvial discharge from the Changjiang River. However, respiration data has rarely been collected in other seasons. To evaluate and reveal the potential controlling mechanism of organic carbon consumption in spring in the ECS, two cruises covering almost the entire ECS shelf were conducted in the spring of 2009 and 2010. These results showed that although the fluvial discharge rates were comparable to the high riverine flow in summer, the plankton community respiration (CR) varied widely between the two springs. In 2009, the level of CR was double that of 2010, with mean (± SD) values of 111.7 (±76.3) and 50.7 (±62.9) mg C m−3 d−1, respectively. The CR was positively correlated with concentrations of particulate organic carbon and/or chlorophyll a (Chl a) in 2009 (all p < 0.01). These results suggest that the high CR rate in 2009 can be attributed to high planktonic biomasses. During this period, phytoplankton growth flourished due to allochthonous nutrients discharged from the Changjiang River. Furthermore, higher phytoplankton growth led to the absorption of an enormous amount of fugacity of CO2 (fCO2) in the surface waters, even with a significant amount of inorganic carbon regenerated via CR. In 2010, even more riverine runoff nutrients were measured in the ECS than in 2009. Surprisingly, the growth of phytoplankton in 2010 was not stimulated by enriched nutrients, and its growth was likely limited by low water temperature and/or low light intensity. Low temperature might also suppress planktonic metabolism, which could explain why the CR was lower in 2010. During this period, lower surface water fCO2 may have been driven mainly by physical process(es). To conclude, these results indicate that high organic carbon consumption (i.e. CR) in the spring of 2009 could be attributed to high planktonic biomasses, and the lower CR rate during the cold spring of 2010 might be likely limited by low temperature in the ECS. This further suggests that the high inter-annual variability of organic carbon consumption needs to be kept in mind when budgeting the annual carbon balance.

scholarly journals Contrasting composition of terrigenous organic matter in the dissolved, particulate and sedimentary organic carbon pools on the outer East Siberian Arctic Shelf

2016 ◽  
Author(s):  
Joan A. Salvadó ◽  
Tommaso Tesi ◽  
Marcus Sundbom ◽  
Emma Karlsson ◽  
Martin Kruså ◽  
...  
Keyword(s):  
Organic Carbon ◽  
River Plume ◽  
Outer Shelf ◽  
Carbon Pools ◽  
Laptev Sea ◽  
Lena River ◽  
Lignin Phenols ◽  
East Siberian Sea ◽  
Siberian Arctic ◽  
Thawing Permafrost

Abstract. Fluvial discharge and coastal erosion of the permafrost-dominated East Siberian Arctic delivers large quantities of terrigenous organic carbon (Terr-OC) to marine waters. The composition and fate of the remobilized Terr-OC needs to be better constrained as it impacts the potential for a climate-carbon feedback. In the present study, the bulk isotope (δ13C and Δ14C) and macromolecular (lignin-derived phenols) composition of the cross-shelf exported organic carbon (OC) in different marine pools is evaluated. For this purpose, as part of the SWERUS-C3 expedition (July–September 2014), sediment organic carbon (SOC) as well as water column (from surface and near-bottom seawater) dissolved organic carbon (DOC) and particulate organic carbon (POC) samples were collected along the outer shelves of the Kara Sea, Laptev Sea and East Siberian Sea. The results show that the Lena River and the DOC have a preferential role in the transport of Terr-OC to the outer shelf. DOC concentrations (740–3600 μg L−1) were one order of magnitude higher than POC (20–360 μg L−1), with higher concentrations towards to the Lena River plume. Depleted δ13C, modern Δ14C and lignin phenols concentrations were all well correlated with DOC levels indicating a relatively young terrestrial contribution. In contrast, POC may have a preferential marine origin, as its concentrations were not correlated with isotope and terrestrial biomarker proxies. The δ13C signatures in the three carbon pools varied from −23.9 ± 1.9 ‰ in the SOC, −26.1 ± 1.2 ‰ in the DOC and −27.1 ± 1.9 ‰ in the POC. The Δ14C values ranged between −395 ± 83 ‰ (SOC), −226 ± 92 ‰ (DOC) and −113 ± 122 ‰ (POC). These stable and radiocarbon isotopes were also different between the Laptev Sea and the East Siberian Sea. Both DOC and POC showed a depleted and younger trend off the Lena River plume. The older and more enriched δ13C signatures in the outer-shelf of the ESS suggest instead a greater influence of the sea ice coverage and the Pacific inflow from the east. Lignin phenols exhibited higher OC-normalized concentration in the SOC (0.10–2.34 mg g−1 OC) and DOC (0.08–2.40 mg g−1 OC) than in the POC (0.03–1.14 mg g−1 OC). The good relationship between lignin and Δ14C signatures in the DOC suggests that a significant fraction of the outer-shelf DOC comes from ''young'' Terr-OC. By contrast, the slightly negative correlation between lignin phenols and Δ14C signatures in POC, with higher lignin concentrations in older POC from near-bottom waters, may reflect the off-shelf transport of OC from remobilized permafrost in the nepheloid layer. Moreover, syringyl/vanillyl and cinnamyl/vannillyl phenols ratios presented distinct clustering between DOC, POC and SOC, suggesting that those pools are carrying different Terr-OC of partially different origin. Finally, 3,5-dihydroxybenzoic acid to vanillyl phenols ratios and p-coumaric acid to ferulic acid ratios, used as a diagenetic indicators, enhanced in POC and SOC. This suggests that the remobilized old OC from thawing permafrost, which is mainly transported within these pools, could experience less burial and more mineralization than believed earlier. Overall, DOC is strongly affected by the Lena River plume transporting young Terr-OC from topsoil and/or recently produced vascular pant material, while near-bottom POC and SOC preferentially carries off-shelf old OC released from thawing permafrost.

scholarly journals The large variation in organic carbon consumption in spring in the East China Sea

2012 ◽  
Vol 9 (11) ◽  
pp. 16533-16564
Author(s):  
C.-C. Chen ◽  
G.-C. Gong ◽  
F.-K. Shiah ◽  
W.-C. Chou ◽  
C.-C. Hung
Keyword(s):  
Organic Carbon ◽  
East China Sea ◽  
Phytoplankton Growth ◽  
East China ◽  
Community Respiration ◽  
Changjiang River ◽  
Carbon Consumption ◽  
The East China Sea ◽  
China Sea ◽  
The Changjiang River

Abstract. A tremendous amount of organic carbon respired by planktonic communities has been found in summer in the East China Sea (ECS), and this rate has been significantly correlated with fluvial discharge from the Changjiang River. However, data related to this issue in other seasons have rarely been collected. To evaluate and reveal the potential controlling mechanism of organic carbon consumption in spring in the ECS, research using stations covering almost the entire ECS shelf was conducted in the spring of 2009 and 2010. During both periods, the fluvial discharges were similar, and these rates were comparable to high riverine flow in summer. Interestingly, planktonic community respiration (CR) varied widely in both springs; in 2009, the level of CR was double that of 2010, with mean (± SD) values of 111.7 (± 76.3) and 50.7 (± 62.9) mg C m−3 d−1, respectively. The CR was positively linearly regressed with concentrations of particulate organic carbon and/or chlorophyll a (Chl a) in 2009 (all p< 0.01). These results suggest that the rate was dependent on planktonic activities, especially that of phytoplankton, in 2009. During this period, phytoplankton growth flourished due to allochthonous nutrients discharged from the Changjiang River. Furthermore, higher phytoplankton growth leaded to the absorption of an enormous amount of fugacity of CO2 (fCO2) in the surface waters, even with a significant amount of inorganic carbon regenerated via CR. In 2010, there were even more riverine runoff nutrients into the ECS than in 2009. Surprisingly, the growth of phytoplankton in 2010 was not stimulated by enriched nutrients, and its growth was likely limited by low water temperature and/or low light intensity. Low temperature might also suppress planktonic metabolism, and this could explain why the CR was lower in 2010. During this period, lower surface water fCO2 might have mainly been driven by physical process(es). To conclude, these results indicate that organic carbon consumption (i.e. CR) in the ECS in spring might be controlled by the magnitude of planktonic activities and physical factor (e.g. temperature), and that the latter is especially important during a cold spring season. This further suggests that the high intraseasonal variability of organic carbon consumption needs to be kept in mind when budgeting the annual carbon balance.

Photosynthetic organic carbon production and respiratory organic carbon consumption in the trophogenic layer of Lake Biwa

1995 ◽  
Vol 17 (5) ◽  
pp. 1017-1025 ◽  
Author(s):  
Mikio Takahashi ◽  
Takeo Hama ◽  
Katsuji Matsunaga ◽  
Nobuhiko Handa
Keyword(s):  
Organic Carbon ◽  
Lake Biwa ◽  
Carbon Consumption ◽  
Carbon Production
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