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1.
Based on survey data from April to May 2009, distribution and its influential factors of dissolved inorganic nitrogen (DIN) over the continental slopes of the Yellow Sea (YS) and East China Sea (ECS) are discussed. Influenced by the Changjiang (Yangtze) River water, alongshore currents, and the Kuroshio current off the coast, DIN concentrations were higher in the Changjiang River estuary, but lower (<1 μmol/L) in the northern and eastern YS and outer continental shelf area of the ECS. In the YS, the thermocline formed in spring, and a cold-water mass with higher DIN concentration (about 11 μmol/L) formed in benthonic water around 123.2°E. In Changjiang estuary (around 123°E, 32°N), DIN concentration was higher in the 10 m layer; however, the bottom DIN concentration was lower, possibly influenced by mixing of the Taiwan Warm Current and offshore currents. 相似文献
2.
To reconstruct the formation and evolution process of the warm current system within the East China Sea (ECS) and the Yellow Sea (YS) since the last deglaciation, the paleoceangraphic records in core DGKS9603, core CSH1 and core YSDPI02, which were retrieved from the mainstream of the Kuroshio Current (KC), the edge of the modem Tsushima Warm Current (TWC) and muddy region under cold waters accreted with the Yellow Sea Warm Current (YSWC) respectively, were synthetically analyzed. The results indicate that the formation and evolution of the modem warm current system in the ECS and the YS has been accompanied by the development of the KC and impulse rising of the sea level since the last deglaciation. The influence of the KC on the Okinawa Trough had enhanced since 16 cal kyr BE and synchronously the modem TWC began to develop with the rising of sea level and finally formed at about 8.5 cal kyr BP. The KC had experienced two weakening process during the Heinrich event 1 and the Younger Drays event from 16 to 8.5 cal kyr BP. The period of 7-6 cal kyr BP was the strongest stage of the KC and the TWC since the last deglaciation. The YSWC has appeared at about 6.4 cal kyr BP. Thus,the warm current system of the ECS and the YS has ultimately formed. The weakness of the KC,indicated by the occurrence of Pulleniatina minimum event (PME) during the period from 5.3 to 2.8 cal kyr BE caused the main stream of the TWC to shift eastward to the Pacific Ocean around about 3 cal kyr BP. The process resulted in the intruding of continent shelf cold water mass with rich nutrients. Synchronously, the strength of the YSWC was relatively weak and the related cold water body was active at the early-mid stage of its appearance against the PME background, which resulted in the quick formation of muddy deposit system in the southeastern YS. The strength of the warm current system in the ECS and the YS has enhanced evidently, and approached to the modern condition gradually since 3 cal kyr BP. 相似文献
3.
A marine survey was conducted from 18 May to 13 June 2014 in the East China Sea(ECS)and its adjacent Kuroshio Current to examine the spatial distribution and biogeochemical characteristics of dissolved oxygen(DO) in spring. Waters were sampled at 10-25 m intervals within 100 m depth, and at 25-500 m beyond 100 m. The depth, temperature, salinity, and density(sigma-t) were measured in situ with a conductivity-temperature-depth(CTD) sensor. DO concentrations were determined on board using traditional Winkler titration method. The results show that in the Kuroshio Current, DO content was the highest in the euphotic layer, then decreased sharply with depth to about 1 000 m, and increased with depth gradually thereafter. While in the ECS continental shelf area, DO content had high values in the coastal surface water and low values in the near-bottom water. In addition, a low-DO zone of f the Changjiang(Yangtze) River estuary was found in spring 2014, and it was formed under the combined influence of many factors, including water stratification, high primary productivity in the euphotic layers, high accumulation/sedimentation of organic matter below the euphotic layers, and mixing/transport of oceanic current waters on the shelf. Most notable among these is the Kuroshio intruded water, an oceanic current water which carried rich dissolved oxygen onto the continental shelf and alleviated the oxygen deficit phenomenon in the ECS, could impact the position, range, and intensity, thus the formation/destruction of the ECS Hypoxia Zone. 相似文献
4.
To reconstruct the formation and evolution process of the warm current system within the East China Sea (ECS) and the Yellow
Sea (YS) since the last deglaciation, the paleoceangraphic records in core DGKS9603, core CSH1 and core YSDP102, which were
retrieved from the mainstream of the Kuroshio Current (KC), the edge of the modern Tsushima Warm Current (TWC) and muddy region
under cold waters accreted with the Yellow Sea Warm Current (YSWC) respectively, were synthetically analyzed. The results
indicate that the formation and evolution of the modern warm current system in the ECS and the YS has been accompanied by
the development of the KC and impulse rising of the sea level since the last deglaciation. The influence of the KC on the
Okinawa Trough had enhanced since 16 cal kyr BP, and synchronously the modern TWC began to develop with the rising of sea
level and finally formed at about 8.5 cal kyr BP. The KC had experienced two weakening process during the Heinrich event 1
and the Younger Drays event from 16 to 8.5 cal kyr BP. The period of 7–6 cal kyr BP was the strongest stage of the KC and
the TWC since the last deglaciation. The YSWC has appeared at about 6.4 cal kyr BP. Thus, the warm current system of the ECS
and the YS has ultimately formed. The weakness of the KC, indicated by the occurrence of Pulleniatina minimum event (PME) during the period from 5.3 to 2.8 cal kyr BP, caused the main stream of the TWC to shift eastward to
the Pacific Ocean around about 3 cal kyr BP. The process resulted in the intruding of continent shelf cold water mass with
rich nutrients. Synchronously, the strength of the YSWC was relatively weak and the related cold water body was active at
the early-mid stage of its appearance against the PME background, which resulted in the quick formation of muddy deposit system
in the southeastern YS. The strength of the warm current system in the ECS and the YS has enhanced evidently, and approached
to the modern condition gradually since 3 cal kyr BP.
Supported by the National Natural Science Foundation of China (Nos. 90411014 and 40506015), the National major Fundamental
Research and Development Project (No. 2007CB815903) and the CAS Pilot Project of the National Knowledge Innovation Program
(No. KZCFX3-SW-233) 相似文献
5.
Journal of Oceanology and Limnology - The Yellow Sea (YS) and East China Sea (ECS) are important marginal seas of the western Pacific. Understanding the dynamics of methane (CH4) in the YS and ECS... 相似文献
6.
lmooUcrI0NSuspendedrnatter(SM)wasanimPortantsubjeCtofstudyincomPrehensiveoasnographicsurveyinChinaintheendofthel950s.Inthel97ds,somesdentistSpeonjo,l974,Yatomoto,l979,EInery,l978)studndextenSiveynoncombustiblematterandgrainsizedistributionsinSManditSreintionshiptoupwelling.Inthel980s,TotaIsuspendedmatternyM)distributionintheEastChinaSea(Ees)wasinvestisatalduringtheChinaisjointstudyonsedhedynaAnesthere.YangZuosheng(l992)distaltherelationbeweenthemacrostrUctureofSMtIansportanddistrib… 相似文献
7.
In this paper, we use the conductivity-temperature-depth (CTD) observation data and a three-dimensional ocean model in a seasonally-varying
forcing field to study the barrier layer (BL) in the PN section in the East China Sea (ECS). The BL can be found along the
PN section with obviously seasonal variability. In winter, spring and autumn, the BL occurs around the slope where the cold
shelf water meets with the warm Kuroshio water. In summer, the BL can also be found in the shelf area near salinity front
of the Changjiang (Yangtze) River Dilution Water (YRDW). Seasonal variations of BL in the PN section are caused by local hydrological
characteristics and seasonal variations of atmospheric forcing. Strong vertical convection caused by sea surface cooling thickens
the BL in winter and spring in the slope area. Due to the large discharge of Changjiang River in summer, the BL occurs extensively
in the shelf region where the fresh YRDW and the salty bottom water meet and form a strong halocline above the seasonal thermocline.
The formation mechanism of BL in the PN section can be explained by the vertical shear of different water masses, which is
called the advection mechanism. The interannual variation of BL in summer is greatly affected by the YRDW. In the larger YRDW
year (such as 1998), a shallow but much thicker BL existed on the shelf area.
Supported by National Basic Research Program of China (973 Program, No. 2005CB422303 and 2007CB411804), the Key Project of
the International Science and Technology Cooperation Program of China (No. 2006DFB21250), the “111 Project” of the Ministry
of Education (No. B07036), the Program for New Century Excellent Talents in University, China (No. NECT-07-0781) 相似文献
8.
Clay minerals and geochemistry of the bottom sediments in the northwestern East China Sea 总被引：1，自引：0，他引：1
Jeungsu YOUN Shouye YANG Yong Ahn PARK 《中国海洋湖沼学报》2007,25(3):235-246
Clay minerals of 34 sediments collected from the northwestern continental shelf of the East China Sea have been determined by X-ray diffraction analysis. The clay mineral distribution is mainly controlled by the sediment source and the dominant circulation pattern. The predominant clay mineral in our study area is illite comprising more than 67% of the whole clay fraction. The highest concentration of illite (>68%) is found in the southeastern offshore parts beyond the reach of terrigenous input from the Jeju Island. It means that these illites are largely transported by the Kuroshio Current from the South China Sea (SCS). Smectite is highly concentrated in the northwest middle part and in the outer-shelf mud patch. It seems to be due to the high supply of smectite transported from China where fine-grained sediments are discharged from modern and ancient Huanghe (Yellow) River. The relatively high abundant kaolinite is likely derived from the Changjiang (Yangtze) River via the Taiwan Warm Current. In contrast, large amounts of chlorite and high chlorite/kaolinite ratios occur in the northwestern area, reflecting the transportation by the Yellow Sea Coastal Current from the southern Yellow Sea. The discrimination diagrams clearly show that the sediments in the northwestern East China Sea are ultimately sourced from Chinese rivers, especially from the Huanghe River, whereas the sediment in the northeast part might come from the Jeju Island. The muddy sediments of the Changjiang River’s submerged delta have much lower 87Sr/86Sr ratios (0.716 2–0.718 0) than those of the Shandong Peninsular mud wedge (0.721 6–0.724 9), which are supposed to be originated from the Huanghe River, suggesting the distribution pattern of 87Sr/86Sr ratios as a new tracer to discriminate the provenance of shelf sediments in the study area. The 87Sr/86Sr ratios of the outer-shelf muddy sediments ranged from 0.7169 to 0.7216 in a wide range and was between those of the Huanghe River and Changjiang River sediments, suggesting multiple sources of the sediment in the area. 相似文献
9.
With sulfide increasingly recognized as an important parameter to assess the oxidation-reduction level in aqueous environment, research on its geochemical behavior is becoming important. Water samples collected in Bohai Sea(1–19 August, 2010), Yellow Sea(20–30 November, 2010) and East China Sea(3–17 June, 2010 and 1–10 November, 2010) were used to determine the occurrence and distribution of dissolved sulfide by methylene blue spectrophotometric method. Results show that:(1) horizontally, concentration of dissolved sulfide significantly varied from the coastal region to the open sea and profoundly influenced by physical processes. High values occurred in the river-sea boundary zone "marginal filter" due to rich riverine input, frequent upwelling and active exchange in shelf edge. Terrestrial input from adjacent rivers and the current cycling contributed to the high sulfide appeared in western Bohai Sea, eastern Shandong Peninsula, and northeast of Changjiang(Yangtze) River estuary. Especially, relative higher sulfide values occurred in Yellow Sea, which is consistent with the variation of salinity largely due to the hydrodynamic feature;(2) vertically, measurement of dissolved sulfide in bottom water was higher and more variable than that in surface water caused by the wind-induced resuspension and dissimilatory sulfate reduction. Moreover, nutrient-type profile clearly identified that oxidation plays a major role in the biogeochemistry cycle of sulfide in water;(3) seasonally, investigation for East China Sea in June and November reflected seasonal variation of Changjiang River Diluted Water, Kuroshio Current, and Taiwan Warm Current. Concentration in June was much higher than that sampled in November at most stations. Mean concentration of dissolved sulfide varied seasonally from 2.26 μg/L(June) to 1.16 μg/L(November) in surface and 3.00 μg/L(June) to 1.56 μg/L(November) in bottom. Progress in the field is slow and more effort is needed to ensure the accuracy and reliability of determination and estimate the natural or anthropogenic contribution of dissolved sulfide in ecosystems. 相似文献
10.
Relationships between phytoplankton community composition and environmental variables in the East China Sea (ECS) and Yellow
Sea (YS) were investigated using geochemical and molecular microbiology methods. The diversity of phytoplankton was characterized
using cultivation-independent PCR-based denaturing gradient gel electrophoresis (DGGE). Groups resulting from unweighted pair-group
method with arithmetic averages clustering of the DGGE profiles showed good consistency with the eco-environmental characteristics
of the sea area they belonged to. Additionally, the clustering results based on DGGE fingerprinting and those based on morphological
compositions were practically identical. The relationship of phytoplankton diversity to environmental factors was statistically
analyzed. Temperature, dissolved inorganic nitrogen (DIN), and silicate-Si were found significantly related to the phytoplankton
community composition. Canonical correspondence analysis (CCA) was performed to reveal the relationship between community
composition and these three environmental factors. Generally, values of the ECS are clearly separated from those of the YS
in the CCA biplot, due to mainly the effect of temperature and DIN. 相似文献
11.
Seasonal variations of several main water masses in the southern Yellow Sea and East China Sea in 2011 总被引：3，自引：1，他引：2
Qi Quan Xinyan Mao Xiaodan Yang Yingying Hu Haiyan Zhang Wensheng Jiang 《中国海洋大学学报(英文版)》2013,12(4):524-536
The seasonal variations of several main water masses in the southern Yellow Sea (SYS) and East China Sea (ECS) in 2011 were analyzed using the in-situ data collected on four cruises. There was something special in the observations for the Yellow Sea Warm Current (YSWC), the Yellow Sea Cold Water Mass (YSCWM) and the Changjiang Diluted Water (CDW) during that year. The YSWC was confirmed to be a seasonal current and its source was closely associated with the Kuroshio onshore intrusion and the northerly wind. It was also found that the YSCWM in the summer of 2011 occupied a more extensive area in comparison with the climatologically-mean case due to the abnormally powerful wind prevailing in the winter of 2010 and decaying gradually thereafter. Resulting from the reduced Changjiang River discharge, the CDW spreading toward the Cheju Island in the summer of 2011 was weaker than the long-term mean and was confined to flow southward in the other seasons. The other water masses seemed normal without noticeable anomalies in 2011. The Yellow Sea Coastal Current (YSCC) water, driven by the northerly wind, flowed southeastward as a whole except for its northeastward surface layer in summer. The Taiwan Warm Current (TWC) was the strongest in summer and the weakest in winter in its northward movement. The Kuroshio water with an enhanced onshore intrusion in autumn was stable in hydrographic features apart from the seasonal variation of its surface layer. 相似文献
12.
The ecological environment in the Yellow Sea has changed greatly from the 1950s to 1990s and this has had significant impact on marine organisms. In this study, data on soft-sediment macrobenthos occurring in depths from 25 m to 81 m in the South Yellow Sea were used to compare changes in community structure. The agglomerative classification (CLUSTER) and multidimensional scaling (MDS) methods were applied. Five communities were recognized by cluster analysis: 1. The Yellow Sea Cold Water Mass community dominated by cold water species, which changed slightly in species composition since the 1950s; 2. The mixed community with the coexistence of cold water species and warm water species, as had been reported previously; 3. The polychaete-dominated eurythermal community in which the composition changed considerably as some dominant species disappeared or decreased; 4. The Changjiang (Yangtze) River Estuarine community, with some typical estuarine species; 5. The community affected by the Yellow Sea Warm Current. The greatest change occurred in the coastal area, which indicated that the change may be caused by human activities. Macrobenthos in the central region remained almost unchanged, particularly the cold water species shielded by the Yellow Sea Cold Water Mass. The depth, temperature and median grain size of sediments were important factors affecting the distributions of macrobenthos in the South Yellow Sea. 相似文献
13.
Fatty acids(FAs) in sediment collected from three different stations in the Yellow Sea and the East China Sea were analyzed for their distributions and to determine evidence of harmful algal blooms in the sediment core.Less diverse FAs were found in the Yellow Sea(YS) station,whereas in the two stations of the East China Sea(ECS) the FAs were more diverse.Concentrations of some FA species in the two ECS stations displayed an occasional surge in their vertical profile.The highest concentration of FAs was found in the surface layer of station QT3(43.28 μg g~(-1)).Monounsaturated FAs were more susceptible to degradation compared to their saturated counterparts,and changes of 16:0,18:2 and 20:5 accounted for the most variability in total concentrations of FAs as those species made up most of the quantified FAs.The origins of the major fraction of FAs were attributed to autotrophic sources,and bacterial FAs accounted for only a small fraction of the total FAs in the region.Nutrient availability was a possible regulating factor controlling bacteria abundances in marine sediments in the ECS and the YS.A principal component analysis(PCA) was applied to analyze the FA dataset and to reveal the principal environmental factors that control the composition of FAs in the sediments.PC2,which explains 15% of the variance,was estimated to reflect the diagenetic effects on the FA compositional changes in sediments influenced by bacterial degradation. 相似文献
14.
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
15.
Analysis of seasonal variation of water masses in East China Sea 总被引：5，自引：0，他引：5
Seasonal variations of water masses in the East China Sea （ECS） and adjacent areas are investigated, based on historical data of temperature and salinity （T-S）. Dynamic and thermodynamic mechanisms that affect seasonal variations of some dominant water masses are discussed, with reference to meteorological data. In the ECS above depth 600 m, there are eight water masses in summer but only five in winter. Among these, Kuroshio Surface Water （KSW）, Kuroshio Intermediate Water （KIW）, ECS Surface Water （ECSSW）, Continental Coastal Water （CCW）, and Yellow Sea Surface Water （YSSW） exist throughout the year. Kuroshio Subsurface Water （KSSW）, ECS Deep Water （ECSDW）, and Yellow Sea Bottom Water （YSBW） are all seasonal water masses, occurring from May through October. The CCW, ECSSW and KSW all have significant seasonal variations, both in their horizontal and vertical extents and their T-S properties. Wind stress, the Kuroshio and its branch currents, and coastal currents are dynamic factors for seasonal variation in spatial extent of the CCW, KSW, and ECSSW, whereas sea surface heat and freshwater fluxes are thermodynamic factors for seasonal variations of T-S properties and thickness of these water masses. In addition, the CCW is affected by river runoff and ECSSW by the CCW and KSW. 相似文献
16.
Journal of Oceanology and Limnology - The intrusion of the Kuroshio into the East China Sea (ECS) affects the development of hypoxia off the Changjiang (Yangtze) River estuary; however,... 相似文献
17.
Lei Xing Yiqing Jiang Zineng Yuan Hailong Zhang Li Li Liping Zhou Meixun Zhao 《中国海洋大学学报(英文版)》2013,12(4):599-604
As an important marginal sea under the influences of both the Changjiang River and the Kuroshio, the East China Sea (ECS) environment is sensitive to both continental and oceanic forcing. Paleoenvironmental records are essential for understanding the long-term environmental evolution of the ECS and adjacent areas. However, paleo-temperature records from the ECS shelf are currently very limited. In this study, the U 37 K′ and TEX86 paleothermometers were used to reconstruct surface and subsurface temperature changes of the mud area southwest of the Cheju Island (Site F10B) in the ECS during the Holocene. The results indicate that temperature changes of F10B during the early Holocene (11.6–6.2 kyr) are associated with global climate change. During the period of 6.2–2.5 kyr, the similar variability trends of smoothing average of ΔT (the difference between surface and subsurface temperature) of Site F10B and the strength of the Kuroshio suggest that the Kuroshio influence on the site started around 6.2 kyr when the Kuroshio entered the Yellow Sea and continued to 2.5 kyr. During the late Holocene (2.5–1.45 kyr), apparent decreases of U 37 K′ sea surface temperature (SST) and ΔT imply that the direct influence of the Kuroshio was reduced while cold eddy induced by the Kuroshio gradually controlled hydrological conditions of this region around 2.5 kyr. 相似文献
18.
INTRODUCTIONPhosphorus (P)isanimportantlimitingelementinglobaloceanicproductivity (Holland ,1 978) ,soknowledgeofPisakeytobetterunderstandingofthecyclingofcarbon ,nitrogen,sulfur,andothernu trientelements.Inasimplemassbalancemodel,thelevelofdissolvedPintheoceanisafunctionoftherateofinputviarivers,andtherateofoutputviadepositioninsediments.Inthepresentstudy,thefocusisontheriverinePinputbytheHuangheRiver (YellowRiver)totheBohaiSea,andespeciallyontheamountofPsolubilizedfromsolidphasesupo… 相似文献
19.
Study of the distribution and migration of the common squid,Todarodes pacificus Steenstrup,basedon the index of important fishing ground(P) and fisheries statistics on the Yellow Sea and northern EastChina Sea during 1980—1991 showed that:1.Its catch in the fishing period(June to November) is 91.77% of the annual yield.The fishingground distributes over the northem and middle Yel1ow Sea and adjacent area of the Changjiang Estuary.2. It over-winters in the northem East China Sea and waters adjacent to Goto Island from De-cember to February and spawns in waters near Haijiao Is1and and west of Kyushu. The main stock mi-grates along 123°30′E to the ChangJiang Estuary, Haizhou Bay. offsea from Shidao to Qingdao,mideastern Yellow Sea, and offsea Weihai and Haiyang Island succesively for feeding after April. The sur-plus stock migrates again to the wintering ground in December.3.The favorable feeding temperature is 6-23℃(optimum of l3-20℃ in the Changjiang Estua-ry and 7-13℃ in the northern and middle Yel 相似文献
20.
The circulations off the Changjiang mouth in May and November were simulatedby a three dimension numerical model with monthly averaged parameters of dynamic factors in this paper. The area covers the East China Sea (ECS), Yellow Sea and Bohai Sea. Simulated results show that the circulation off the Changjiang mouth in spring and autumn is mainly the Changjiang runoff and Taiwan Warm Current (TWC). The Changjlang discharge is much larger in May than in November, and the wind is westward in May, and southward in November offthe Changjiang mouth. The runoff in May branches in three parts, one eastward flows, the other two flow northward and southward along the Subei and Zhejiang coast respectively. The Changjiang diluted water expands eastward off the mouth, and forms a strong salinity front near the mouth. Surface circulation in autumn is similar to that in winter, the runoff southward flows along the coast, and the northward flowing TWC becomes weaker compared to that in spring and summer. The bottom circulations in May and November are mainly the runoff near the mouth and the TWC off the mouth, and the runoff and TWC are greater in May than in November. 相似文献