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ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｈｏｒｉｚｏｎｔａｌｃｕｒｒｅｎｔｉｎｔｈｅｓｅａｏｒｏｃｅａｎｉｓａｍａｊｏｒｆａｃｔｏｒａｆｆｅｃｔｉｎｇｓｅｄｉｍｅｎｔｅｒｏｓｉｏｎ ,ｔｒａｎｓ ｐｏｒｔ,ｄｅｐｏｓｉｔｉｏｎ ,ｅｔｃ.Ｔｈｅｒｅｆｏｒｅ,ｍｏｓｔｗｏｒｋｄｏｎｅｗａｓｏｎｔｈｅｅｆｆｅｃｔｏｆｈｏｒｉｚｏｎｔａｌｃｕｒｒｅｎｔ.Ｆｅｗｏ ｃｅａｎｏｇｒａｐｈｅｒｓｈａｖｅｔａｋｅｎｎｏｔｅｏｆｔｈｅｉｎｆｌｕｅｎｃｅｏｆｖｅｒｔｉｃａｌｃｉｒｃｕｌａｔｉｏｎｏｎｔｈｅｓｕｓｐｅｎｄｅｄｍａｔｔｅ… 相似文献
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UPWELLING AND SEDIMENTATION DYNAMICS Ⅲ：COINCIDENCE OF UPWELLING AREAS WITH MUD PATCHES IN NORTH HEMISPHERE SHELF SEAS 总被引：1，自引：0，他引：1
The determinant role of upwelling in fine sediment patches is examined from the view-points of physical process and biological process respectively. It is pointed out that physical and biologicalprocesses are usually coexistent and interact with each other during the sedimentation of suspended mat-ters. This study used available figures showing the circulation pattern and surface sediment distribution inthe whole China Seas, the Gulf of Maine, the Irish Sea and the North Sea, and additional data to verifythat wherever upwelling exists on the continental shelf, mud must occur; and that wherever dowrtwellingoccurs, coarse sediment substitutes for mud. 相似文献
4.
Hu Dunxin 《中国海洋湖沼学报》1984,2(1):12-19
It is found that the mud distributions in the Huanghai Sea and East China Sea are extremely identical with the upwelling's in terms of locality and extent. The process of the mud formation is examined. It is concluded that vertical circulation i.e. upwelling plays a determinant role in the process and furthermore, it is inferred that wherever upwelling occurs on continental shelf, mud should be formed and, conversely, wherever downwelling takes place, mud should not exist, for which coarse sediment should substitute. 相似文献
5.
Distribution of suspended matter in seawater in the Southern Yellow Sea is investigated in five regions: 1) the Northern Jiangsu
bank, the highest TSM (total suspended matter) content region; 2) the high TSM content region off the Changjiang River mouth;
3) the high TSM content region off the Chengshan Cape; 4) the low TSM region off Haizhou Bay; 5) the central part of the Southern
Yellow Sea, a low TSM content region. The vertical distribution of TSM is mainly characterized by a spring layer of suspended
matter, written as “suspended-cline” whose genesis is related to storms in winter. In this paper, non-combustible components
and grain sizes in suspended matter, relationship between suspended matter and bottom sediments, and salinity in seawater
are described. Investigation result shows that, in this area, suspended matter comes mainly from resuspended bottom sediment
and secondarily from present discharge loads from rivers and biogenic materials. Discharged sediments from the Huanghe River
move around the Chengshan Cape and affect the northwestern region of this area. Sediments from the Changjiang River affect
only the southern part and have little or no direct influence on the central deep region. Wave is the main factor affecting
distribution of suspended matter. Water depth controls the critical depth acted on by waves. The cold water mass in the central
region limits horizontal and vertical dispersions of terrigenous materials. Suspended matter here has the transitional properties
of the epicontinental sea. Its concentration and composition are different from those of a semi-closed sea (such as the Bohai
Sea) and those of the East China Sea outer continental shelf or those near oceanic areas. 相似文献
6.
The distribution of the suspended sediment concentration (SSC) in the Bohai Sea, Yellow Sea and East China Sea (BYECS) is studied based on the observed turbidity data and model simulation results. The observed turbidity results show that (i) the highest SSC is found in the coastal areas while in the outer shelf sea areas turbid water is much more difficult to observe, (ii) the surface layer SSC is much lower than the bottom layer SSC and (iii) the winter SSC is higher than the summer SSC. The Regional Ocean Modeling System (ROMS) is used to simulate the SSC distribution in the BYECS. A comparison between the modeled SSC and the observed SSC in the BYECS shows that the modeled SSC can reproduce the principal features of the SSC distribution in the BYECS. The dynamic mechanisms of the sediment erosion and transport processes are studied based on the modeled results. The horizontal distribution of the SSC in the BYECS is mainly determined by the current-wave induced bottom stress and the fine-grain sediment distribution. The current-induced bottom stress is much higher than the wave-induced bottom stress, which means the tidal currents play a more significant role in the sediment resuspension than the wind waves. The vertical mixing strength is studied based on the mixed layer depth and the turbulent kinetic energy distribution in the BYECS. The strong winter time vertical mixing, which is mainly caused by the strong wind stress and surface cooling, leads to high surface layer SSC in winter. High surface layer SSC in summer is restricted in the coastal areas. 相似文献
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The Huanghe (Yellow) River, with annual sediment discharge about 11 ×108tons, contributes about 17% of the fluvial sediment discharge of world's 21 major rivers to the ocean because its middle reaches flow across the great Loess Plateau of China. Sediment discharge of the Huanghe River has a widespread and profound effect on sedimentation of the sea. The remarkable shift of its outlet in 1128-1855 A.D. to the South Yellow Sea formed a large subaqueous delta and provided the substrate for an extensive submarine ridge field.The shift of its outlet in the modern delta every 10 years is the main reason why with an extremely heavy sediment input and a micro- tidal environment, the Huanghe River has not succeeded in building a birdfoot delta like the Mississippi. The Huanghe River has consistently brought heavy sediment input to sea at least since 0.7 myr.B.P. Paleochannels, paleosols, cheniers and fossils on the sea bottom indicate that the Yellow Sea was exposed during the late Quaternary glacial low-sea l 相似文献
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Study on the seasonal variation of the suspended sediment distribution and transportation in the East China Seas based on SeaWiFS data 总被引：2，自引：0，他引：2
The monthly mean suspended sediment concentration in the upper layer of the East China Seas was derived from theretrieval of the monthly binned SeaWiFS Level 3 data during 1998 to 2006.The seasonal variation and spatial distribution of thesuspended sediment concentration in the study area were investigated.It was found that the suspended sediment distribution presentsapparent spatial characteristics and seasonal variations,which are mainly affected by the resuspension and transportation of the sus-pended sediment in the study area.The concentration of suspended sediment is high inshore and low offshore,and river mouths aregenerally high concentration areas.The suspended sediment covers a much wider area in winter than in summer,and for the samesite the concentration is generally higher in winter.In the Yellow and East China Seas the suspended sediment spreads farther to theopen sea in winter than in summer,and May and October are the transitional periods of the extension.Winds,waves,currents,ther-mocline,halocline,pycnocline as well as bottom sediment feature and distribution in the study area are important influencing factorsfor the distribution pattern.If the 10mg L-1 contour line is taken as an indicator,it appears that the transportation of suspended sedi-ment can hardly reach 124°00'E in summer or 126°00'E in winter,which is due to the obstruction of the Taiwan Warm Current andthe Kuroshio Current in the southern Yellow Sea and the East China Sea. 相似文献
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1 INTRODUCTION The Yellow Sea is a shallow epicontinental sea surrounded by Chinese mainland and Korean Peninsula. It is connected with the East China Sea to the south, and with the Bohai Sea to the north- west. Water depth is generally less than 80 m with average of 44 m (Qin et al., 1989). The major sediment sources are the Huanghe and Changjiang (Yangtze) Rivers, providing annual sediment load of about 1.1×109 and 4.9×108 tons, respectively. A maximum of 1.6×108 tons of sedime… 相似文献
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lmooUcrI0NSuspendedrnatter(SM)wasanimPortantsubjeCtofstudyincomPrehensiveoasnographicsurveyinChinaintheendofthel950s.Inthel97ds,somesdentistSpeonjo,l974,Yatomoto,l979,EInery,l978)studndextenSiveynoncombustiblematterandgrainsizedistributionsinSManditSreintionshiptoupwelling.Inthel980s,TotaIsuspendedmatternyM)distributionintheEastChinaSea(Ees)wasinvestisatalduringtheChinaisjointstudyonsedhedynaAnesthere.YangZuosheng(l992)distaltherelationbeweenthemacrostrUctureofSMtIansportanddistrib… 相似文献
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The concentration of suspended load can be determined by its linear relationship to turbidity. Our results present the basic
distribution of suspended load in North Yellow Sea. In summer, the suspended load concentration is high along the coast and
low in the center of the sea. There are four regions of high concentration in the surface layer: Penglai and Chengshantou
along the north of the Shandong Peninsula, and the coastal areas of Lüshun and Changshan Islands. There is a 2 mg/L contour
at 124°E that separates the North Yellow Sea from regions of lower concentrations in the open sea to the west. And there is
a 2 mg/L contour at 124°E that separates the North Yellow Sea from regions of lower concentrations in the open sea to the
west. The distribution features in the 10 m and bottom layer are similar to the surface layer, however, the suspended load
concentration declines in the 10 m layer while it increases in the bottom layer. And in the bottom layer there is a low suspended
load concentration water mass at the region south of 38°N and east of 123°E extending to the southeast. In general, the lowest
suspended load concentration in a vertical profile is at a depth of 10 to 20 m, the highest suspended load concentration is
in the bottom near Chengshantou area.
In winter, the distribution of suspended load is similar to summer, but the average concentrations are three times higher.
There are two tongue-shaped high suspended load concentration belt, one occurring from surface to seafloor, extends to the
north near Chengshantou and the other invades north to south along the east margin of Dalian Bay. They separate the low suspended
load concentration water masses in the center of North Yellow Sea into east and west parts. Vertical distribution is quite
uniform in the whole North Yellow Sea because of the cooling effect and strong northeast winds. The distribution of suspended
load has a very close relationship to the current circulation and wind-induced waves in the North Yellow Sea. Because of this,
we have been able to show for the first time that the distribution of suspended load can be used to identify water masses. 相似文献
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To study the relationship between sediment transportation and saltwater intrusion in the Changjiang (Yangtze) estuary, a three-dimensional numerical model for temperature, salinity, velocity field, and suspended sediment concentration was established based on the ECOMSED model. Using this model, sediment transportation in the flood season of 2005 was simulated for the Changjiang estuary. A comparison between simulated results and observation data for the tidal level, flow velocity and direction, salinity and suspended sediment concentration indicated that they were consistent in overall. Based on model verification, the simulation of saltwater intrusion and its effect on sediment in the Changjiang estuary was analyzed in detail. The saltwater intrusion in the estuary including the formation, evolution, and disappearance of saltwater wedge and the induced vertical circulation were reproduced, and the crucial impact of the wedge on cohesive and non-cohesive suspended sediment distribution and transportation were successfully simulated. The result shows that near the salinity front, the simulated concentrations of both cohesive and non-cohesive suspended sediment at the surface layer had a strong relationship with the simulated velocity, especially when considering a 1-hour lag. However, in the bottom layer, there was no obvious correlation between them, because the saltwater wedge and its inducing vertical circulation may have resuspended loose sediment on the bed, thus forming a high-concentration area near the bottom even if the velocity near the bottom was very low during the transition phase from flood to ebb. 相似文献
13.
Investigations and studies for years all demonstrated that there is a patch of fine-grained mud in the central area of the
South Yellow Sea. However, scientists have different opinions on its material source, genesis, and sedimentation intensity.
Some believe that the materials come from the Huanghe River, some think that the mud area represents the depocentre of the
South Yellow Sea, and some consider it as “relict mud”. The authors' geochemical study reveals that the mud is multi-sourced,
yet the material supply is not ample, and that a little amount of fine-grained suspended materials deposited slowly under
the dynamic action of a cyclonic gyre formed the modern muddy sediment, which is named “multi-source modern mud”.
Project supported by the National Natural Science Foundation of China, contribution No. 1646 from the Institute of Oceanology,
Academia Sinica. 相似文献
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ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅ“ｇｒｅｅｎｈｏｕｓｅｅｆｆｅｃｔ”ｒｅｓｕｌｔｉｎｇｆｒｏｍｔｈｅｉｎｃｒｅａｓｉｎｇｃａｒｂｏｎｄｉｏｘｉｄｅｉｎｔｈｅａｔｍｏｓｐｈｅｒｅｓｉｇｎｉｆｉ ｃａｎｔｌｙａｆｆｅｃｔｓｔｈｅｇｌｏｂａｌａｖｅｒａｇｅｔｅｍｐｅｒａｔｕｒｅ (Ｄｅｔｅｒ,1 978) ,ｈａｓｄｒａｗｎｔｈｅａｔｔｅｎｔｉｏｎｏｆｓｃｉｅｎｔｉｓｔｓａｒｏｕｎｄｔｈｅｗｏｒｌｄ .Ｓｃｉｅｎｔｉｓｔｓｃｏｎｓｉｄｅｒｔｈａｔｋｎｏｗｌｅｄｇｅｏｆｔｈｅｏｃｅａｎ’ｓｃａｐａｃｉｔｙｔｏａｂｓｏｒ… 相似文献
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MIN Jianxiong LI Guangxue DING Dong QIAO Lulu MA Yanyan YANG Gang ZHANG Yaqi ZHANG Lei LI Shuhao 《中国海洋大学学报(英文版)》2019,(1)
Based on the observed surface suspended matter in the East China Sea in February 2007 and June 2015, an empirical model was established using L1 b's band 4 data to retrieve surface suspended matter from the Moderate Resolution Imagine Spectroradiometer Terra imagery. The squared correlation coefficient is 0.8358, and the root mean square error is 0.4285 mg L-1. The model reflects the distribution characteristics of surface suspended matter in the inner shelf of the East China Sea. In this paper, the satellite images of the study area were retrieved in January from 2001 to 2015, and the monthly distribution of surface suspended matter were obtained. The inter-annual distribution of the study area is similar, and the concentration of surface suspended matter is higher near the shore than offshore. A large amount of surface suspended matter is transported southeast under the influence of Zhejiang and Fujian coastal current and Taiwan warm current. Only a small amount of surface suspension can reach the Kuroshio area. The surface suspended matter concentration changes obviously near the estuary because of the effect of differences in the flux of the Yangtze River. Meanwhile, winter monsoon, temperature front, El Ni?o events, and other factors affect the distribution of surface suspended matter in 100 m isobath to coastal water but minimally influence the distribution in 100 m isobath to deep sea. 相似文献
16.
A modelling study of inter-annual variation of Kuroshio intrusion on the shelf of East China Sea 总被引：2，自引：1，他引：1
Inter-annual variability of the Kuroshio water intrusion on the shelf of East China Sea (ECS) was simulated with a nested global and Northwest Pacific ocean circulation model. The model analysis reveals the influence of the variability of Kuroshio transport east of Taiwan on the intrusion to the northeast of Taiwan: high correlation (r = 0.92) with the on-shore volume flux in the lower layer (50–200 m); low correlation (r = 0.50) with the on-shore flux in the upper layer (0–50 m). Spatial distribution of correlations between volume fluxes and sea surface height suggests that inter-annual variability of the Kuroshio flux east of Taiwan and its subsurface water intruding to the shelf lag behind the sea surface height anomalies in the central Pacific at 162°E by about 14 months, and could be related to wind-forced variation in the interior North Pacific that propagates westward as Rossby waves. The intrusion of Kuroshio surface water is also influenced by local winds. The intruding Kuroshio subsurface water causes variations of temperature and salinity of bottom waters on the southern ECS shelf. The influence of the intruding Kuroshio subsurface water extends widely from the shelf slope northeast of Taiwan northward to the central ECS near the 60 m isobath, and northeastward to the region near the 90 m isobath. 相似文献
17.
This research on the influence of sediment resuspension on the flux of materials in the margin of the East China Sea showed
that the sediment resuspension rates, was 47.40%–79.18% in the surface layers, and 72.75%–96.96% in the bottom layers. The
research confirmed that the Changjiang River runoff and the eddy area upwelling flow near 125°E were two important factors
affecting the sediment resuspension in summer; the transformation of DOC to POC through the flocculation in the transitional
region (123°–124°E) was also confirmed by comparison of the resuspension rate. The sediment resuspension was shown to be influenced
by the seasonal factor, especially in the surface layer.
Contribution No. 4017 from the Institute of Oceanology, Chinese Academy of Sciences.
Project 49636210 supported by NSFC. 相似文献
18.
《中国海洋湖沼学报》2021,(2)
Typhoon is one of the frequent natural disasters in coastal regions of China.As shown in many studies,the impact of typhoons on the South China Sea(SCS) should not be overlooked.Super typhoon Rammasun(2014) was studied that formed in the northwestern Pacific,passed through the SCS,then landed in the Leizhou Peninsula.Remote sensing data and model products were used to analyze the spatiotemporal variations of the cold eddies,upwelling,sea surface temperature,mixed layer depth,rainfall,sea surface salinity,suspended sediment concentration,and surface-level anomaly.Results confirm the constant presence of upwelling and cold eddies in the southeast of Hainan(north of the Zhongsha Islands) and the southeast of Vietnam in July.In addition,we found the strengthening effect of super typhoon Rammasun on the upwelling and cold eddies in the SCS.The major reasons for the continuous decrease in sea surface temperature and the slow regaining of seawater temperature were the enhanced upwelling and vertical mixing caused by the typhoon.The increasing of the surface runoff in the Indochina Peninsula was mainly affected by the typhoon,with some contribution for the southeast of Vietnam's cold eddy and upwelling. 相似文献
19.
On the basis of our study of the present sediments in the northern part of the continental shelf of the South China Sea, this article clarifies our views that a "three-zone pattern" is the basic feature of transgression-type sedimentation.The classification of transgression-type sedimentation of the present continental shelf is based on: the close relationships between the formation of the present continental shelf and the position of the low sea level of the Wiirrn glacial stage, the genetic types and environmental features of sedimentary zoning, the relationship between the formation of glauconite with different maturity and the migration of coastline, the speed of transgression, and the overlying speed of sedimentation. We put forward the genetic name of the "three-zone pattern" to denote:1.The inner zouu, river mouth-coastal current sedimentary area;2.The intermediate zone, coastal current-sea current scouring-sedimentary area;3.The outer zone, sea current scouring area.All these are of significance 相似文献
20.
Based on the field data obtained during cruises on the shelf of the East China Sea from 1997 to 1999, seasonal variations of coastal upwelling on the inner shelf are discussed by using cross-shelf transect profiles and horizontal distributions of chemical and hydrographic variables. Results show that the coastal upwelling was year-round, but the areas and intensities of the upwelling were quite different in season. The coastal upwelling occurred in all of the coastal areas of the region in spring and summer, but in autumn only in the area off Zhejiang Province, and in winter in the area off Fujian Prov- ince. It was the strongest in summer and the weakest in winter. Geographically, it was the strongest in the area off Zhejiang Province and the weakest in the southmost or northmost parts of the East China Sea. The estimated nutrient fluxes upward into euphotic zone through coastal upwelling were quite large, es- pecially for phosphate, which contributed significantly to primary production and improved the nutrient structure of the coastal ecosystem in the East China Sea. 相似文献