Studies on the community structures of meiofauna and marine nematode at six stations in the Southern Yellow Sea,China

1Introduction As part of a comprehensive investigation of ecosys-tem dynamics in the Yellow Sea and East China Sea,astudy has been made of meiofauna,defined here asmetazoans passing a0.5mm sieve but retained by a0.031mm sieve.Meiofauna is an important energeticgroup in benthic small food web due to their smallsize,high abundance and fast turnover rates.Theproduction of meiofauna is equal to or higher than thatof macrofauna in estuaries,shallow waters and deepseas(Gerlach,1971;Platt and Warw…     

The effect of the East China Sea Kuroshio Front on the marine atmospheric boundary layer

Various satellite data, JRA-25 (Japan reanalysis of 25 years) reanalyzed data and WRF (Weather Research Forecast) model are used to investigate the in situ effect of the ESKF (East China Sea Kuroshio Front) on the MABL (marine atmospheric boundary layer). The intensity of the ESKF is most robust from January to April in its annual cycle. The local strong surface northerly/northeasterly winds are observed right over the ESKF in January and in April and the wind speeds decrease upward in the MABL. The thermal wind effect that is derived from the baroclinic MABL forced by the strong SST gradient contributes to the strong surface winds to a large degree. The convergence zone existing along the warm flank of the ESKF is stronger in April than in January corresponding to the steeper SST (sea surface temperature) gradient. The collocations of the cloud cover maximum and precipitation maximum are basically consistent with the convergence zone of the wind field. The clouds develop higher (lower) in the warm (cold) flank of the ESKF due to the less (more) stable stratification in the MABL. The lowest clouds are observed in April on the cold flank of the ESKF and over the Yellow Sea due to the existence of the pronounced temperature inversion. The numerical experiments with smoothed SST are consistent with the results from the ovservations.     

A new species ofPraebebalia (Crustacea: Brachyura: Leucosiidae) from East China Sea

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Phytoplankton distribution and community structure in the East China Sea (ECS) continental shelf

ＩＮＴＲＯＤＵＣＴＩＯＮＰｈｙｔｏｐｌａｋｔｏｎｈａｓａｋｅｙｒｏｌｅｉｎｔｈｅｍａｒｉｎｅｅｃｏｓｙｓｔｅｍａｓｔｈｅｂａｓｉｃｐａｒｔｉｎｔｈｅｆｏｏｄｃｈａｉｎ ,ｗｈｉｃｈｉｓｉｍｐｏｒｔａｎｔｉｎｆｏｒｍａｔｉｏｎｆｏｒａｓｓｅｓｓｉｎｇｐｒｏｄｕｃｔｉｖｉｔｙｐｏｔｅｎｔｉａｌａｎｄｆｉｓｈｅｒｙｒｅｓｏｕｒｃｅｓ.Ｐｈｙｔｏｐｌａｎｋｔｏｎａｌｓｏｈａｓａｎｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｔｈｅｃａｒｂｏｎｂｉｏｇｅｏｃｈｅｍｉｃａｌｃｙｃｌｅ,ｂｅｃａｕｓｅｉｔｃａｎａｂｓｏｒｂａｌａ…     

HETEROTROPHIC BACTERIOPLANKTON PRODUCTION IN THE EAST CHINA SEA

ＩＮＴＲＯＤＵＣＴＩＯＮＭｏｒｅｔｈａｎａｄｅｃａｄｅｈａｓｐａｓｓｅｄｓｉｎｃｅｂａｃｔｅｒｉａｗａｓｒｅｃｏｇｎｉｚｅｄａｓｑｕａｎｔｉｔａｔｉｖｅｌｙｉｍｐｏｒｔａｎｔｃｏｎ ｓｕｍｅｒｓｏｆｏｒｇａｎｉｃｃａｒｂｏｎｉｎｍａｒｉｎｅｆｏｏｄｗｅｂｓａｎｄｍａｒｉｎｅｅｃｏｓｙｓｔｅｍｓ (Ｆｕｈｒｍａｎ ,1 992 ) .ＴｈｅｂａｓｉｃｉｎｆｏｒｍａｔｉｏｎｏｎｔｈｅｓｉｇｎｉｆｉｃａｎｃｅｏｆｔｈｅｍｉｃｒｏｂｉａｌｆｏｏｄｗｅｂｗａｓｐｒｅｓｅｎｔｅｄｂｙＰｏｍｅｒｏｙ ( 1 974 ) ,ｗｈｏｐｉｅ…     

DISSOLVED ORGANIC CARBON IN THE EAST CHINA SEA IN AUTUMN

ImODUcrIONThepoolofdissolvedorganicrnatter,eva1uatalasdissolvedorganiccarbonpoC),hasbostudndforrnanyycars(Med,l964,SkopintSevCtal.,l966).Continentalmar-ginshavedrihypotheSedtobeasirnPortanttothemarinecarbonbiogeochdricalCy-desasthedeepsea(Walsh,l99l),butinmostdiscussions,onlyexportofparticulateorganieswasconsidetal.HighconcentIationofDOCincoastalwatershasaspedlroleinexportingcarbonfromcontinentalmarginstotheopenocean.UndelstandingtheroleoftheoceanmarginsintheglobalcarbonCycAsdependsla…     

A THREE-DIMENSIONAL THERMOCLINE MODEL FOR THE YELLOW SEA AND NORTHERN EAST CHINA SEA

A time-dependent, three-dimensional finite difference model is presented for simulating the stratifiedYellow Sea and northem East China Sea. The mode is forced by time-dependent observed wind, surfaceflux of heat, and tidal turbulence. With this model, momentum and temperature distribution can be computed,and an approximation for the sub-grid scale effects is introduced by the use of mass and momentumexchange coefficients. The vertical exchanges are quite dependent on these assumed coefficents, whichare complicated functions of the turbulence energy of tide and wind, of the stratified strength and otherfactors. This model was applied to describe the mechanics of the variations in strength and thickness ofthe thermocline covering almost the whole Yellow Sea and northern East Chna Sea in summer. Comparisonsof the computed output with obtained survey data led to some important conclusions.     

Two new species of the genusDorylaimopsis Ditlevsen, 1918 (Nematoda: Adenophora,Comesomatidae) from the Bohai Sea,China

Two nematode species of the genusDorylaimopsis (Family Comesometidae) from the Bohai Sea are described.Dorylaimopsis rabalaisi n. sp. similar toD. punctata Ditlevsen, 1918 from which it can be separated by the small size, short and simple spicules without ventral apophyses or joint line.Dorylaimopsis turneri n. sp. differs from the closest speciesDorylaimopsis angelae (Inglis, 1967) by its higher values of de Man ratio ‘a’, much shorter spicules and higher ratio of gubernacular to spicules length. A key to species of the genus based on the key by Jensen (1979) is given. This project was supported by the National Science Foundation, No: 3860804     

TRANSPORT OF SUSPENDED MATTER FROM THE CHANGJIANG RIVER TO THE EAST CHINA SEA SHELF

lmooUcrI0NSuspendedrnatter(SM)wasanimPortantsubjeCtofstudyincomPrehensiveoasnographicsurveyinChinaintheendofthel950s.Inthel97ds,somesdentistSpeonjo,l974,Yatomoto,l979,EInery,l978)studndextenSiveynoncombustiblematterandgrainsizedistributionsinSManditSreintionshiptoupwelling.Inthel980s,TotaIsuspendedmatternyM)distributionintheEastChinaSea(Ees)wasinvestisatalduringtheChinaisjointstudyonsedhedynaAnesthere.YangZuosheng(l992)distaltherelationbeweenthemacrostrUctureofSMtIansportanddistrib…     

A NEW SPECIES OF THE GENUS NEROCILA （ISOPODA： CYMOTHOIDAE） FROM THE EAST CHINA SEA

A new species of cymothoid Isopeda, Nerocila donghaiensis, collected from the body of a sciaenid fish, Johnius sp., is described in the present paper. The new species can be distinguished from the other species of genus Nerocila by its endoped of uropods with deep notch, sharply serrated on the lateral margin and strongly serrated on the medial margin; antennule with 1 st article swollen; dactyli of pereopods Ⅰ, Ⅱ, Ⅳ, Ⅴ swollen.     

Cold event at 5 500 a BP recorded in mud sediments on the inner shelf of the East China Sea

A 700-year record (1.0–1.5 a resolution) of the East Asian winter monsoon (EAWM), based on grain-size analysis and AMS¹⁴C dating of Core EC2005 from the inner-shelf mud wedge of the East China Sea (ECS), was compared with the Dongge stalagmite δ¹⁸O record during the mid-Holocene. The upper muddy section of Core EC2005 has been formed mainly by suspended sediments derived from the Changjiang (Yangtze) River mouth since 7.3 ka BP. High precipitation and a strengthened EAWM might have played key roles in the high sedimentation rate (1 324–1 986 cm/ka) between 5.9–5.2 ka BP. The EAWM strengthened when the Asian summer monsoon weakened, especially around 5 500 a BP, which corresponded to a worldwide cold event. The EAWM during the mid-Holocene shows statistically significant solar periodicities at 62 and 11 a. The 5 500 a BP cold event might be resulted from orbital forcing and changes in solar activity.     

A probe heat flow value of the East China Sea shelf

Bottom temperature variation (BTV) is a serious problem in determining the thermal gradient and heart flow of the sediments in shallow seas. The water depth of the East China Sea shelf is mostly below 150m, and the heat flow measurement is strongly affected by BTV. Following a statistical algorithm, we rechecked the temperature and thermal conductivity data of the cruises KX90-1 and KX91-1, carried out by a cooperation program of China and Japan, and calculate the heat flow in a site without long-term temperature record. The calculated heat flow in the site was 58.6±3.6 mW/m², being just within the range of the drill heat flow value of East China Sea shelf. The inversed amplitude spectrum of BTV has a peak in frequency of 1/10 per year, and the annual component is also an important part. Comparison with two lakes of Lake Greifensee and Lac Leman (i.e. Lake Geneva), which are in different water depth, revealed that with increasing water depth, the peak of amplitude spectrum moved towards low frequency components. The heat flow values calculated in this paper and from petroleum bore hole in East China Sea shelf are much more close to that in southeast China than in Okinawa Trough. Supported by the National High Technology R&D Program of China (2004 AA616060)     

Macrobenthic community structure and species composition in the Yellow Sea and East China Sea in jellyfish bloom

To understand the characteristics of macrobenthic structures and the relationship between environment and benthic assemblages in jellyfish bloom, we studied the macrobenthos and related environmental factors in the coastal waters of the Yellow Sea and East China Sea. Data were collected during two seasonal cruises in April and August of 2011, and analyzed with multivariate statistical methods. Up to 306 macrobenthic species were registered from the research areas, including 115 species of Polychaeta, 78 of Crustacea, 61 of Mollusca, 30 of Echinodermata, and 22 of other groups. Nine polychaete species occurred at frequencies higher than 25% from the sampling stations： Lumbrineris longifolia, Notomastus latericeus, Nin6e palmata, Ophelina acuminata, Nephtys oligobranchia, Onuphis geophiliformis, Glycera chirori, Terebellides stroemii, and Aricidea fragilis. Both the average biomass and abundance of macrobenthos are higher in August （23.8 g/m^2 and 237.7 ind./m^2） than those in April （11.3 g/m^2 and 128 ind./m^2）; the dissimilarity ofmacrobenthic structures among stations is as high as 70%. In terms of the dissimilarity values, we divided the stations into four clusters in spring and eight in summer. The ABC curve shows that the macrofauna communities in high jellyfish abundance were not changed. Canonical correspondence analysis showed that depth, temperature, median grain size, total organic carbon of sediment and total nitrogen in sediment were important factors affecting the macrozoobenthic community in the study area.     

Numerical Study of Water and Suspended Matter Exchange Between the Yellow Sea and the East China Sea

INTRODUCTIONTheYellowSeaandtheEastChinaSea (ECS)aremarginalseasofthenorthwestPacificandhaveexpansivecontinentalshelves .TheuniqueandstrikingfeaturesoftheYellowSeaandtheECSarethattheyhavestrongtidalcurrent;aresubjecttostrongmonsooninfluence ;andreceiveinflowfromthebiggestriverinChina ,theChangjiangRiver ;andthatthefamouswesternboundarycurrent,theKuroshio ,passesthroughtheECS ,withitsbranchesintrudingupwardintothecontinentalshelfareas.Generallyspeaking ,thewaterexchangecapacityofthe…     

Retrieval of inherent optical properties of the Yellow Sea and East China Sea using a quasi-analytical algorithm

We tested and modified the quasi-analytical algorithm (QAA) using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coefficients of typical coastal waters. The average percentage difference (APD) is in a range of 13.9%–38.5% for the total absorption coefficient (13.9% at 440 nm), and differences in particle backscattering coefficient bbp(λ) are less than 50% (in the case of the updated QAA). To obtain improved res...     

The formation of wind curl in the marine atmosphere boundary layer over the East China Sea Kuroshio in spring

Various data are used to investigate the characteristics of the surface wind field and rainfall on the East China Sea Kuroshio (ESK) in March and April, 2011. In March, the wind speed maximum shows over the ESK front (ESKF) in the 10 meter wind field, which agrees with the thermal wind effect. A wind curl center is generated on the warm flank of the ESKF. The winds are much weaker in April, so is the wind curl. A rainband exists over the ESKF in both the months. The Weather Research and Forecasting (WRF) model is used for further researches. The winds on the top of the marine atmosphere boundary layer (MABL) indicate that in March, a positive wind curl is generated in the whole MABL over the warm flank of the ESKF. The thermal wind effect forced by the strong SST gradient overlying the background wind leads to strong surface northeasterly winds on the ESKF, and a positive shearing vorticity is created over the warm flank of the ESKF to generate wind curl. In the smoothed sea surface temperature experiment, the presence of the ESKF is responsible for the strong northeast winds in the ESKF, and essential for the distribution of the rainfall centers in March, which confirms the mechanism above. The same simulation is made for April, 2011, and the responses from the MABL become weak. The low background wind speed weakens the effect of the thermal wind, thus no strong Ekman pumping is helpful for precipitation. There is no big difference in rainfall between the control run and the smooth SST run. Decomposition of the wind vector shows that local wind acceleration induced by the thermal wind effect along with the variations in wind direction is responsible for the pronounced wind curl/divergence over the ESKF.     

Biodiversity of free-living marine nematodes in the southern Yellow Sea,China

Biodiversity patterns of free-living marine nematodes were studied using specific,taxonomic and phylogenetic diversity measures in the southern Yellow Sea,China.The results showed that the average of Shannon-Wiener diversity index(H′) in the study area was 3.17.The higher values were distributed in the east part of Shandong coastal waters and north part of Jiangsu coastal waters,while the lower values were distributed in the southern Yellow Sea Cold Water Mass(YSCWM).The average of taxonomic diversity(Δ) was 62.09 in the study region.The higher values were distributed in the transitional areas between the coastal areas and the southern YSCWM,while the lower values were distributed near the north part of Jiangsu coastal waters and the YSCWM.Results of correlation analysis of species diversity and taxonomic diversity showed that some of the two kinds of diversity index were independent,which suggested that combining the two kinds of diversity indices can reflect the ecological characteristics better.A test for 95% probability funnels of average taxonomic distinctness and variation in taxonomic distinctness suggested that Station 8794(in the YSCWM) was outside of the 95% probability funnels,which may be due to the environmental stress.Results of correlation analysis between marine nematodes biodiversity and environmental variables showed that the sediment characteristics(Md? and Silt-clay fraction) and phaeophorbide a(Pha-a) were the most important factors to determine the biodiversity patterns of marine nematodes.     

STUDY OF WATER—TRANSPORT THROUGH SOME MAIN STRAITS IN THE EAST CHINA SEA AND SOUTH CHINA SEA

OCCAM global ocean model results were applied to calculate the monthly water transport through 7 straits around the East China Sea(ECS)and the South china Sea(SCS).Analysis of the features of velocity profiles and their variations in the Togara Strait,Luzon Strait and Eastern Taiwan Strait showed that;1)the velocity profiles had striped pattern in the Eastern Taiwan Strait,where monthly flux varied from 22.4 to 28.1 Sv and annual mean was about 25.8 Sv;2)the profiles of velocity in the Togara Strait were characterized by core structure,and monthly flux varied from 23.3 to 31.4 Sv,with annual mean of about 27.9 Sv;3)water flowed from the SCS to the ECS in the Taiwan Strait,with maximum flux of 3.1 Sv in July and minimum of 0.9 Sv in November;4)the flux in the Tsushima Strait varied by only about 0.4 Sv by season and its annual mean was about 2.3 Sv;5)Kuroshio water flowed into the SCS in the Luzon Strait throughout the year and the velocity profiles were characterized by multi-core structure.The flux in the Luzon Strait was minimun in June(about 2.4 Sv)and maximum in February(about 9.0 Sv),and its annual mean was 4.8 Sv;6)the monthly flux in the Mindoro Strait was maximum in December(3.0 Sv)and minimum in June(Only 0.1 Sv),and its annual mean was 1.3 Sv;7)Karimata Strait water flowed into the SCS from May to August,with maximum in-flow flux of about 0.75 Sv in June and flowed out from September to April at maximum outflow flux of 3.9 Sv in January.The annual mean flux was about 1.35 Sv.