2003 Vol. 22, No. 3

Physical Oceanography,Marine Meteorology and Marine Physics
The circulation in the southern Huanghai Sea and northern East China Sea in June 1999
Yaochu Yuan, Yonggang Liu, Mingyu Zhou, Arata Kaneko, Zhou Yuan, Noriaki Gohda
2003, (3): 321-332.
Abstract:
On the basis of hydrographic data and current measurement (the mooring system, vessel-mounted ADCP and toward ADCP) data obtained in June 1999, the circulations in the southern Huanghai Sea (HS) and northern East China Sea (ECS) are computed by using the modified inverse method. The Kuroshio flows northeastward through eastern part of the investigated region and has the main core at Section PN, a northward flow at the easternmost part of Section PN, a weaker anti-cyclonic eddy between these two northward flows, and a weak cyclonic eddy at the western part of Section PN. The above current structure is one type of the current structures at Section PN in ECS. The net northward volume transport (VT) of the Kuroshio and the offshore branch of Taiwan Warm Current (TWCOB) through Section PN is about 26.2×106m3/s in June 1999. The VT of the inshore branch of Taiwan Warm Current (TWCIB) through the investigated region is about 0.4×106m3/s. The Taiwan Warm Current (TWC) has much effect on the currents over the continental shelf. The Huanghai Sea Coastal Current (HSCC) flows southeastward and enters into the northwestern part of investigated region, andflows to turn cyclonically, and then it flows northeastward, due to the influences of the Taiwan Warm Current and topography. There is a cyclonic eddy south of Cheju Island where the Huanghai Sea CoastalCurrent flows to turn cyclonically. It has the feature of high dense and cold water. The uniform and coldwater is occurred in the layer from about 30 m level to the bottom between Stations C306 and C311 atthe northernmost Section C3. It is a southern part of the Huanghai Sea Cold Water Mass (HSCWM).
Three-dimensional calculations of the currents in the Huanghai Sea and East China Sea during June of 1999
Huiqun Wang, Yaochu Yuan, Yonggang Liu, Mingyu Zhou
2003, (3): 333-349.
Abstract:
Based on the wind and hydrographic data obtained by R/V Xiangyanghong 14 duringJune of 1999, the currents in the Huanghai Sea and East China Sea are computed by the three dimensional non-linear diagnostic, semidiagnostic models and prognostic in the a coordinate. The computed results show that the density and velocity fields and so on have been adjusted when time is about 3 days, namely the solution of semidiagnostic calculation is obtained. In the northwest part of the computed region, the Huanghai coastal current flows southeastward, and then it flows out the computed region south of Cheju Island. In the west side of the southern part of the computed region, there is other current, which is mainly inshore branch of Taiwan Warm Current, and it flows cyclonically and turns to the northeast. In the region north of the above two currents, there is a cyclonic eddy southwest of Cheju Island, and it has characteristics of high density and low temperature. There is an offshore branch of Taiwan Warm Current in the west side of the Kuroshio, and it makes a cyclonic meander, then flows north-eastward. The Kuroshio in the East China Sea is stronger, and flows northeastward. Its maximum hori-zontal velocity is 108.5 cm/s at the sea surface, which is located at the northern boundary, and it is 106.1 cm/s at 30 m level, 102.2 cm/s at 75 m level and 85.1 cm/s at 200 m level, respectively, whichare all located at the southern boundary. Comparing the results of diagnostic calculation with those ofsemidiagnostic and prognostic calculations indicates that the horizontal velocity field agrees qualitatively,and there is a little difference between them in quantity. The comparison between the computed veloci-ties and the obeered velocities at the mooring station show that they agree each other.
Study on interaction between the coastal water, shelf water and Kuroshio water in the Huanghai Sea and East China Sea
Binghuo Guo, Xiaomin Hu, Xuejun Xiong, Renfeng Ge
2003, (3): 351-367.
Abstract:
The main processes of interaction between the coastal water, shelf water and Kuroshiowater in the Huanghai Sea (HS) and East China Sea (ECS) are analyzed based on the observation and study results in recent years. These processes include the intrusion of the Kuroshio water into the shelf area of the ECS, the entrainment of the shelf water into the Kuroshio, the seasonal process in the southern shelf area of the ECS controlled alternatively by the Taiwan Strait water and the Kuroshio water intruding into the shelf area, the interaction between the Kuroshio branch water, shelf mixed water and modified coastal water in the northeastern ECS, the water-exchange between the HS and ECS and the spread of the Changjiang diluted water.
Marine Meteorology
Air-sea heat flux exchange over the South China Sea under different weather conditions before and after southwest monsoon onset in 2000
Junyue Yan, Huadong Yao, Jianglong Li, Zhiyi Tang, Guorong Jiang, Wenyu Sha, Xunqiang Li, Yiguo Xiao
2003, (3): 369-383.
Abstract:
With the data observed from the Second SCS Air-Sea Flux Experiment on the Xisha air-sea flux research tower, the radiation budget, latent, sensible heat fluxes and net oceanic heat budgets were caculated before and after summer monsoon onset. It is discovered that, after summer monsoon onset, there are considerable changes in air-sea fluxes, especially in latent heat fluxes and net oceanic heat budget. Furthermore, the analyzed results of five synoptic stages are compared. And the characteristics of the flux transfer during different stages around onset of South China Sea monsoon are discussed. The flux change shows that there is an oceanic heat accumulating process during the pre-onset and the break period, as same as oceanic heat losing process during the onset period. Moreover, latent fluxes, the water vapor moving to the continent, even the rainfall appearance in Chinese Mainland also can be influenced by southwester. Comparing Xisha fluxes with those obtained from the Indian Ocean and the western Pacific Ocean, their differences may be obeerved. It is the reason why SSTs can keep stableover the South China Sea while they decrease quickly over the Arabian Sea and the Bay of Bengal aftermonsoon onset.
Marine Chemistry
The chemical distribution characteristics of variant form phosphorus in the seawater of the South China Sea
Jianming Pan, Chuanyu Hu, Jianfang Chen, Xiaoya Liu, Huaiyang Zhou, Weidong Ji
2003, (3): 385-394.
Abstract:
According to two cruises investigation information in summer and winter during 1998 and 1999, the phosphorous concentration distribution and changes of summer and winter were discussed primarily in the South China Sea. The results show that the phosphate concentration of surface seawater in summer is distinctly lower than that in winter, averaging 0.04 μmol/dm3 in summer and 0.35 μmol/dm3 in winter. The organic phosphorous concentration of surface seawater in summer is higher than that in winter, averaging 0.12 μmol/dm3 in summer and 0.04 μmol/dm3 in winter respectively. The seasonal changes of total phosphorus are similar to phosphate, averaging 0.22 μmol/dm3 in summer and 0.61 μmol/dm3 in winter respectively. In vertical direction, phosphate, TDP and TP content are the lowest in upper 50 m water column, and increase in linearity rapidly with water depth, increasing slowly under 500 m, reach to maximum about 1 000 m, then decrease slightly with water depth increasing. The vertical distribution is typical in summer, and there is small dispersed for phosphorus concentration for thesame depth of different stations. However, in winter there is a large disperse for phosphate, TDP andTP, specifically for phosphate at 200 m at which the concentration is maximum. This result indicatesthat there are large differences in hydrology and biology conditions that affect largely the chemical environment of the South China Sea. The organic phosphorus is the predominant in surface seawater of the South China Sea, but the inorganic phosphorus is the predominant in layers below depth of 150 m. Theorganic phosphorus concentration in deep water usually decreases with water depth increasing. The or-ganic phosphorus in summer is remarkably more than that in winter because of the strong biology activities in summer.
Marine Geology and Geomorphology
Preliminary study on taxonomy of dinoflagellate cysts from major estuary and bays of Fujian Province, China
Dongzhao Lan, Chao Li, Qi Fang, Haifeng Gu
2003, (3): 395-406.
Abstract:
According to the morphology, wall structure, color, ornamentation, etc., 25 species belonging to 9 genera are identified and described from 144 sediment samples of the Xiamen Harbor, the mouth of the Minjiang River and the Sansha Bay. Among them there are 2 toxic species:Alexandrium minutun, A. tamarenes, 4 harmful species:Alexandrium affine, Lingulodinium polyedrum, Scrippsiella trochoide, Gonyaulax spinifera. It shows that 11 species of dinoflagellate cysts (Alexandrium affine, A. minutum, Diplopelta cf. parva, Polykrikos cf. schwartzii, protoceratium reticulatum, Protoperidinium minutum, P. cf. minutum,P. cf americanum and Alexandrium sp., Protoperidinium sp. 1, P. sp. 2) are first recorded along the coast of Fujian Province, China. These newly discovered species might be transported to the coastal sea of Fujian Province by ballast water of international trade vessels.
Dinoflagellate cysts in recent marine sediment from Guangxi, China
Haifeng Gu, Qi Fang, Jun Sun, Dongzhao Lan, Feng Cai, Zhiyong Gao
2003, (3): 407-419.
Abstract:
Total of 33 species of dinoflagellate cysts were discovered from surface sediment in the searegion of Guangxi, among them 12 cyst types (Diplopsalopsis sp.1, D. sp. 2, D. sp. 3, Cochlodinium sp., Protoperidinium sp. 1, P. sp. 2, P. compressum, Scrippsiella sp. 1, S. sp. 2, Alexandrium sp. 1, A. sp. 2, A. sp. 3) were first reported from the South China Sea. And one cyst type (Cochlodinium sp.) was first reported in the world. Scrippsiella trochoidea is the dominant species in this area, accounting for 45% of all the cysts. There are 2 cysts of toxic dinoflagellate (Alexandrium tamarensis and Gymnodinium catenatum). But there is no relationship between cyst number and grain size distribution.
Marine Biology and Fishery
Studies on rickettsia-like organism (RLO) disease of tropical marine pearl oyster-Epidemiological investigation of RLO disease in juvenile populations of maricultured Pinctada maxima
Xinzhong Wu, Dengfeng Li, Jinpei Pan, Jingbo Jiang
2003, (3): 421-435.
Abstract:
The death which occurred in juvenile population was a severe problem in the course ofPinctada maxima artificial culture. With the methods of field investigation, histological study and statistic analyses, the epidemiological study was carried out on the disease and death in juvenile populations of Pinctada maxima in the Xinying Pearl Oyster Mariculture Farm of Lingao County (for the A, B and C batches of cultured juveniles hanged in the sea) and the Xincun Pearl Oyster Mariculture Farm of Lingshui County (for the D batch of cultured juvenile hanged in the pond), Hainan Province from November 1993 to April 1995.
The results show that the deaths which occurred in juvenile populations of Pinctada maxima presented an outbreak pattern. The peak of mortality rates, in general, occurred in 4-to 6-month old pearl oyster juveniles, and the mortality rates gradully declined with the extention of pearl oyster age after cul-turing 8 months. The correlation between the mortality rates of juvenile populations and mean bodylengths of juvenile populations show that the mortality rate become higher under 4 cm of mean bodylengths of juvenile population and become obvious declined over 5 cm of mean body lengths. The peak ofmortality rate occurred in 1~3 cm of mean body lengths. The results of histological observation showedthat rickettsia-like organism inclusions were common, histological widespread infective agent among ev-ery batches (A, B, C and D) of cultured juvenile populations. The mean severity indices (SI) of rick-ettsia-like organism (RLO) infection were positively correlated with mortality rates of juvenile populations. After or within every peaks of RLO infection were all accompanied with the peaks of mortalityrates of host populations and the mortality rates declined with decreased RLO infection. So the evidencesof histological observation and epidemiology in this study indicated that rickettsia-like organism (RLO)may be as an important pathogenic organism of disease and death of cultured Pinctada maxima. In addition, a few ciliates were discovered only in part of batch A of cultured juvenile population. The mortalityrates in juvenile populations were not correlated with the weekly mean temperature and salinity of seawater.
Four new recorded species of marine nanoplanktonic diatoms found in the East China Sea and Huanghai Sea
Yang Li, Yahui Gao
2003, (3): 437-442.
Abstract:
In a study of species composition of marine nanoplanktonic diatoms (<20μm) in watersamples from the East China Sea and Huanghai Sea (Yellow Sea), four diatom species were identified by TEM as new records for China. They were Thalassiosira oceanica Hasle, Navicula britannica Hustedt et Aleem, Nitzschia leehyi Fryxell and Synedra indica Taylor. Detailed description of the taxo-nomic characteristics with TEM photographs of the four species and their ecological behavior and distribution is given in this paper.
Current status of bacteriological parameters and DOC/POC in Xiamen coastal waters
Khalid Maskaoui, Tianling Zheng, Huasheng Hong, Zhiming Yu, Zhong Hu, Yun Tian, Lizhe Cai
2003, (3): 443-451.
Abstract:
The surface and bottom waters samples were collected from six locations in Xiamen western sea. The quantified estimation of bacterial production (3H-thymidine method) and observation of bacterial heterotrophic activity (14C-glucose method) have been made in order to have a better understanding of the role of marine bacteria and their activities. The results showed that the mean value of bacterial heterotrophic activity was 9×108 cells/(L.h) in the surface waters and 2.6×108 cells/(L.h) in the bottom waters. The mean value of bacterial production was 38×108 cells/(L.h) in the surface waters and 7.1×108 cells/(L.h) in the bottom waters. The relationship between bacterial production, heterotrophic activity, POC and DOC measured during this survey were discussed. The good understanding of the relationship between bacteria activity and total coliform was addressed.
Genetic variation of Porphyra yezoensis by using AFLP1
Rui Yang, Biqian Liu, Qijun Luo, Yajun Wang, Jiamei Bao
2003, (3): 453-457.
Abstract:
Genetic variation of 11 lines of Porphyra yezoensis from the coastline of Kagoshima ofJapan, Qingdao, Nantong, Putuo and Nanji Islands of China were studied by using amplified fragment length polymorphism (AFLP).778 bands were obtained with AFLP analysis of 16 primer combinations, among which 15 were unique, about 98.07% were polymorphic. The AFLP data showed that the closest genetic distance was 0.180 between two Kagoshima samples, and the farthest one was 0.397 between Kagoshima No.1 and Nantong No.9 line. The genetic distance showed that the variation was within the inner species scope. Neighbor-joining cluster and UPGMA cluster indicated that samples from Kagoshima and Qingdao were with high similarity and either with the samples of Nantong, Putuo and Nanji Islands. P. yezoensis in China shared high genetic diversity, and the genetic distance showed positive correlation with the geographic distance.
The determination of larval metamorphic competence of Styela canopus Savigny
Ying Huang, Danqing Feng, Caihuan Ke, Shiqiang Zhou
2003, (3): 459-466.
Abstract:
The larvae of Styela canopus show the highest rates of settlement and metamorphosiswhen treated with 40 mM KCl-elevated seawater at 25℃ in temperature and 27.0 in salinity. Induced by 40 mM KCl-elevated seawater, it took Styela canopus larvae approximately 3 h after hatching to develop competence to settle and metamorphose. The present experiment shows that Styela canopus larvae is an ideal model organism for examining the efficiency of antifouling substance.
Marine Engineering
Notes Marine biofouling in Hong Kong: a review
Zongguo Huang
2003, (3): 467-482.
Abstract:
From 1980 to 1998, biofouling communities in Hong Kong waters, the Zhujiang RiverEstuary and the Mirs Bay were studied and a total of 610 samples. The samples were collected from vessels, buoys, piers and cages. Totally, 340 species (see Appendix I) have been recorded and identified, six of which are new. At the same time, research on the biology of the cirripede, bryozoan, polychaete and mollusc communities were also conducted. Twenty-three related papers have been published. This review summarizes works in Hong Kong over past twenty years, and some unpublished data are also reported.
The application of Hartley transform to ocean engineering
Hequan Sun, Dahong Qiu, Yongxue Wang
2003, (3): 483-490.
Abstract:
The Hartley transform is a real integral transform based on harmonic functions and hassome characteristics similar to the Fourier transform. Most applications in ocean engineering requiring the Fourier transform can also be performed by the Hartley transform. The fast Hartley transform is twice faster and more convenient to handle than the corresponding fast Fourier transform, so it is a real valued alternative to the complex Fourier transform in many applications. The use of the Hartley transform in ocean engineering is presented in detail in this paper, including wave spectral analysis, separation of waves, cross-correlation in PIV technique and expression of equation in the Hartley domain. The examples in the paper show deeply the advantage and efficiency of the Hartley transform over the Fourier transform.