scholarly journals Coupling of surface <i>p</i>CO<sub>2</sub> and dissolved oxygen in the northern South China Sea: impacts of contrasting coastal processes

2009 ◽  
Vol 6 (3) ◽  
pp. 6249-6269 ◽  
Author(s):  
W. Zhai ◽  
M. Dai ◽  
W. Cai
Keyword(s):  
South China Sea ◽  
Dissolved Oxygen ◽  
South China ◽  
Coastal Upwelling ◽  
Northern South China Sea ◽  
River Estuary ◽  
Pearl River Estuary ◽  
Deep Basin ◽  
Co2 Partial Pressure ◽  
China Sea

Abstract. We examined the relationship between CO2 partial pressure (pCO2) and dissolved oxygen (DO) based on a cruise conducted in July 2004 to the northern South China Sea, spanning from estuarine plume, coastal upwelling and deep basin areas. Distinct relationships between pCO2 and DO saturation were identified in different regimes. In coastal upwelling areas and the Pearl River estuary, biological drawdown of pCO2 and production of O2 were simultaneously observed. The two properties were coupled with each other primarily via photosynthesis and respiration. The stoichiometric relationship of the two properties however, was quite different in these two environments due to different values of the Revelle factor. In the offshore areas, apart from the estuary and upwelling, the dynamics of pCO2 and DO were mainly influenced by air-sea exchange during water mixing. Given the fact that air-sea re-equilibration of O2 is much faster than that of CO2, the observed pCO2-DO relationship deviated from that of the theoretical prediction based on the Redfield relationship in the offshore areas.

scholarly journals Coupling of surface <i>p</i>CO<sub>2</sub> and dissolved oxygen in the northern South China Sea: impacts of contrasting coastal processes

2009 ◽  
Vol 6 (11) ◽  
pp. 2589-2598 ◽  
Author(s):  
W. D. Zhai ◽  
M. Dai ◽  
W.-J. Cai
Keyword(s):  
South China Sea ◽  
Dissolved Oxygen ◽  
South China ◽  
Coastal Upwelling ◽  
Simple Procedure ◽  
Northern South China Sea ◽  
River Estuary ◽  
Deep Basin ◽  
China Sea ◽  
Spatial Coverage

Abstract. We examined the relationship between CO2 partial pressure (pCO2) and dissolved oxygen (DO) based on a cruise conducted in July 2004 to the northern South China Sea (111°–118° E 18°–23° N), spanning from estuarine plume, coastal upwelling and deep basin areas. Distinct relationships between pCO2 and DO saturation were identified in different regimes. In coastal upwelling areas and the Pearl River estuary, biological drawdown of pCO2 and production of O2 were simultaneously observed. The two properties were coupled with each other primarily via photosynthesis and respiration. The stoichiometric relationship of the two properties however, was quite different in these two environments due to different values of the Revelle factor. In the offshore areas, apart from the estuary and upwelling, the dynamics of pCO2 and DO were mainly influenced by air-sea exchange during water mixing. Given the fact that air-sea re-equilibration of O2 is much faster than that of CO2, the observed pCO2-DO relationship deviated from that of the theoretical prediction based on the Redfield relationship in the offshore areas. Although this study is subject to the limited temporal and spatial coverage of sampling, we have demonstrated a simple procedure to evaluate the community metabolic status based on a combination of high-resolution surface pCO2 and DO measurements, which may have applicability in many coastal systems with a large gradient of changes in their physical and biogeochemical conditions.

A preliminary study on sediment records of possible typhoon in the northern South China Sea during the past 6500 yr

The Holocene ◽  
2021 ◽  
pp. 095968362110032
Author(s):  
Pingyuan Li ◽  
Mingkun Li ◽  
Huayang Gan ◽  
Zhen Xia
Keyword(s):  
South China Sea ◽  
South China ◽  
Southern China ◽  
Northern South China Sea ◽  
River Estuary ◽  
Pearl River Estuary ◽  
Human Beings ◽  
China Sea ◽  
The Pearl River ◽  
China Coast

Typhoon is an important meteorological phenomenon that affects the living and development of human beings on the southern China coast. However, there is still lack of clarity in the paleo-typhoon history and its influence on the evolution of the ancient human settlement environment since the mid-Holocene. Here, we identify six typhoon-like deposits from a core retrieved from the northern South China Sea shelf, close to the Pearl River Estuary, based on accelerated mass spectrometry 14C dating, grain size, and geochemistry. The sand fractions, CaO, Sr, SiO2/TiO2, and SiO2/Al2O3 were used to indicate the typhoon-like deposits. Results show that the ages with high-frequency typhoons are present ~200–300 cal yr BP, ~800–1000 cal yr BP, ~1500–1700 cal yr BP, ~2000–2100 cal yr BP, ~2400–2500 cal yr BP, and ~2700–3000 cal yr BP. Our results are comparable to the records from adjacent regions. Significantly, the vast tides occurred in the duration of ~2700–3000 cal yr BP in southern China, which probably caused the ancestors’ migration to the inland. Further studies are needed to deeply study the paleo-typhoon history in the southern China coast to verify our results.

Dynamics of heterotrophic dinoflagellates off the Pearl River Estuary, northern South China Sea

2009 ◽  
Vol 85 (3) ◽  
pp. 422-430 ◽  
Author(s):  
Wenlu Lan ◽  
Bangqin Huang ◽  
Minhan Dai ◽  
Xiuren Ning ◽  
Lingfeng Huang ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
Northern South China Sea ◽  
River Estuary ◽  
Pearl River Estuary ◽  
Pearl River ◽  
China Sea ◽  
The Pearl River Estuary ◽  
The Pearl River

Factors controlling nitrous oxide in the inner Pearl River Estuary, Northern South China Sea

2012 ◽  
Vol 15 (2) ◽  
pp. 176-184 ◽  
Author(s):  
You-Shao Wang ◽  
Mei-Lin Wu ◽  
Ji-Rong Xu ◽  
Cui-Ci Sun ◽  
Jun-De Dong ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
South China Sea ◽  
South China ◽  
Northern South China Sea ◽  
River Estuary ◽  
Pearl River Estuary ◽  
Pearl River ◽  
China Sea

scholarly journals Phytoplankton response to a plume front in the northern South China Sea

2018 ◽  
Vol 15 (8) ◽  
pp. 2551-2563 ◽  
Author(s):  
Qian P. Li ◽  
Weiwen Zhou ◽  
Yinchao Chen ◽  
Zhengchao Wu
Keyword(s):  
South China Sea ◽  
South China ◽  
Bottom Water ◽  
Coastal Upwelling ◽  
Frontal Zone ◽  
Northern South China Sea ◽  
River Estuary ◽  
Frontal System ◽  
China Sea ◽  
Plume Water

Abstract. Due to a strong river discharge during April–June 2016, a persistent salinity front, with freshwater flushing seaward on the surface but seawater moving landward at the bottom, was formed in the coastal waters west of the Pearl River estuary (PRE) over the northern South China Sea (NSCS) shelf. Hydrographic measurements revealed that the salinity front was influenced by both the river plume and coastal upwelling. On shipboard nutrient-enrichment experiments with size-fractionation chlorophyll a measurements were taken on both sides of the front as well as in the frontal zone to diagnose the spatial variations of phytoplankton physiology across the frontal system. We also assessed the size-fractionated responses of phytoplankton to the treatment of plume water at the frontal zone and the sea side of the front. The biological impact of vertical mixing or upwelling was further examined by the response of surface phytoplankton to the addition of local bottom water. Our results suggested that there was a large variation in phytoplankton physiology on the sea side of the front, driven by dynamic nutrient fluxes, although P limitation was prevailing on the shore side of the front and at the frontal zone. The spreading of plume water at the frontal zone would directly improve the growth of microphytoplankton, while nano- and picophytoplankton growths could have become saturated at high percentages of plume water. Also, the mixing of bottom water would stimulate the growth of surface phytoplankton on both sides of the front by altering the surface N∕P ratio to make it closer to the Redfield stoichiometry. In summary, phytoplankton growth and physiology could be profoundly influenced by the physical dynamics in the frontal system during the spring–summer of 2016.

scholarly journals Using TPI to Map Spatial and Temporal Variations of Significant Coastal Upwelling in the Northern South China Sea

2021 ◽  
Vol 13 (6) ◽  
pp. 1065 ◽  
Author(s):  
Weian Shi ◽  
Zhi Huang ◽  
Jianyu Hu
Keyword(s):  
South China Sea ◽  
South China ◽  
Coastal Upwelling ◽  
Northern South China Sea ◽  
River Estuary ◽  
Temporal Variations ◽  
Mapping Method ◽  
Chl A ◽  
China Sea ◽  
Influence Area

Based on Himawari-8 Sea Surface Temperature (SST) data and the semi-automatic Topographic Position Index (TPI)-based mapping method, this study maps the significant coastal upwelling in the northern South China Sea (NSCS). The results show that the Minnan coastal upwelling mainly occurs within 100 km off the south coast of Fujian; the Yuedong coastal upwelling appears to the east of Pearl River Estuary, limited to the area shallower than 40 m; and the Qiongdong coastal upwelling occurs most frequently in the area shallower than 75 m off the east coast of Hainan Island. Based on the results, this paper quantitatively describes the temporal and spatial variations of upwelling duration, influence area, upwelling SST anomaly, and chlorophyll-a (Chl-a) increase. Different coastal upwelling regions in the NSCS are significantly different in characteristics. The Qiongdong coastal upwelling has the longest duration and occurs most frequently, the Yuedong coastal upwelling has the largest influence area and Chl-a increase, and the Minnan coastal upwelling is quite strong in the NSCS.

Sign in / Sign up

Export Citation Format

Share Document