1995 Vol. 14, No. 1

Display Method:
An alternating direction implicit (ADI) numerical model for two-dimensional hydrodynamic equations
Pan Hai, Fang Guohong
1995, (1): 1-13.
A two-dimensional computational model is developed for the calculation of tides, storm surges and other long-period waves in coastal and shelf waters.The partial differential equations are approximated by two sets of difference equations on a space-staggered grid system.Both sets are implicit with one set for water level and x-component velocity, and another for water level and y-component velocity.These two sets are used successively for step-by-step solution in time.An analytical investigation on the linearized sets of the difference equations indicates that the computational scheme is unconditionally stable.The model is of second order accuracy both in space and in time and conserves mass and momentum.Simulations of surface elevation caused by periodic forcing in one-opening rectangular basin with flat topography and by steady wind stress in the basin with flat or slope topography show that the computed results are in excellent agreement with the corresponding analytic solutions.The steady-tate wind-induced setup in a closed basin with discontinuous topography rnmputed with the present model are also in exceVent agreement with the results from Leendertse's model.Finally, the model is applied to hindcast a storm surge in the South China Sea and reproduces the surge elevation satisfactorily.
Application of the four models of directional spectra in the Bohai Sea
Wu Xiujie, Teng Xuechun
1995, (1): 15-22.
According to the wind-wave individual case directional spectra obtained from the instrument array and ‘956’ wave buoy measures, the wind-wave directional spectra presented by Mitsuyasu, Donelan and Hasselmann on the basis of the observations as well as theoretical wind-wave directional spectra by Wen Shengchang on the basis of analytic method are compared and checked from the pointview of total energy.Results show that Mitsuyasu's directional spectra are well identical with the measured wind-wave directional spectra developing fully in the Bohai Sea.Donelan's and theoretical wind-wave directional spectra are also quite consistent with the measured results in the development of the wind waves, especially best with the measured results in the initial stage of the development of the wind waves.
Identification of biomarkers of cores from the South China Sea
Tang Yunqian, Liu Kewen
1995, (1): 23-37.
The principal factor analysis indicates that short chains nC16, nC17.nC18 and nC19 have relatively large positive charge, while long chains nC27 and nC29 have relatively large negative charge.On the third principal factor axis, the carbon with positive charge is almost even carbon, while the carbon with negative charge is almost odd carbon.The parameters of biomarker compounds are divided into 3 groups; (I) nC31l/nC17,nC27/nC17, nC27/T and Pr/Ph recognizing the input of source material; (2) nC27/T, Ph/nC18, CPI and Pr/Ph showing oxidation and reduction of depositional environment; (3) Tm/Ts, Ph/nC18 indicating the maturity of sedimentary organic matter.
Tracing technique of stable 15N isotope: an application in study of mariculture
Hong Ashi, Li Wenquan, Wang Mingliang
1995, (1): 39-45.
Using Na15NO3 and 15SNH4Cl as tracer, we studied the transfer of 15N along the food chain composed of organisms such as Platymonas subcordifwmis, Anemia saliva, Perwt;u perdcillatus and Liza carinatus.The abundance and atomic percentage of 15N in each organism, as well as the transfer of 15N among different biological phases were measured.Results show that, in the nutrient transfer from low level to high level along the food chain in the media of 15SNH4Cl, the transfer rate of Anemia salivaLiza casinatus exceeded 3% and was higher than that in Na Na15NO3;the accumulation of 15N in the bodies of Lira carinatvs with 15SNH,Cl as media was also higher than that with Na Na15NO3 as media.
Carbonate chemistry and the anthropogenic CO2 in the South China Sea
Chen-Tung Arthur Chen, Ming-Hsiung Huang
1995, (1): 47-57.
In order to understand the water mass exchange between the South China Sea and the West Philippine Sea, and to study the dissolved carbonate system in the seas surrounding Taiwan Island, we participated in five WOCE cruises (Cruises 257, 262, 266, 287 and 316) aboard R/V Ocean Researcher 1.The areas studied were the South China Sea, the West Philippine Sea and the Bashi Channel.Temperature, salinity, pH, alkalinity and total CO2 were measured.
Our data indicate that because of the interference of the submarine topography and the Kuroshio axis, there exists a 0front" south of the Lanyu Islet.East of it, the water mass belongs to the West Philippine Sea, on the west in the mixed water of the South China Sea and the West Philippine Sea.
The South China Sea deep water should have the characteristics similar to the water at about 2 200 m in the West Philippine Sea.The calculated results from the residence time, the inorganic carbon dissolution rate and the organic carbon decomposition rate show that the differences between these two water masses should be between 0.008-0.023 in pH, 5.2-15.0 μmol/kg in apparent oxygen utilization, 3.6-10.2 μmol/kg in alkalinity and 6.4-18.4 pmol/kg in total CO2,respectively.The measured results show that there are no distinguishable differences between these two water masses, implying a short deep water residence time of approximately 40 a.
The anthropogenic CO2 penetrates to roughly 500 m, slightly shallower than found in the West Philippine Sea.The entire South China Sea contains (0.38±0.1)×1015 g excess CO2.
Marine diatoms of the Xisha Islands, South China Sea Mastogloia Thw, Ex, Wm, Smith: species of Group Ellipticae
Liu Shicheng
1995, (1): 59-71.
Seventeen species of diatoms of the genus Mastogloia are recorded.For selected species.the external and internal valve structures are investigated under LM, TEM and SEM microscopes.M.sp.(M.af.cocconeiforntis) is described.
Ecological features of phytoplankton in red tide outburst area in the Xiamen Harbor
Zhang Shuijin
1995, (1): 73-83.
The results from the 38 cruises of phytoplankton surveys in the red tide outburst area in the Xiamen Harbor in 1987 indicate 41 species of red tide organisms among 110 species of phytoplankton identified.Species tomposition was dominant by eurytopic species and warm water species.Species diversity apparently changed with (cold and warm) seasons.There was a high diversity in warm seasons, 63 species in August.Average annual number of phytoplankton reached 1 119×103 ind./dm3 which was 2 to 2.6 times that in 2 control monitoring stations.The number of phytoplankton in horizonal distribution displayed an obvious increasing tendency from the harbour mouth to the inner harbor.The phytoplankton number always changed with time, but with 3 peak values in the year round.The daily change of the phytoplankton number with tide exhibited a negative relativity.Moreover phytoplankton species and their number showed a vertical movement during day and night.Futhermore, 10 predominant species changed with seasons was noted in the present paper.
Lateral ice force acting on a vertical cylinder
Shi Qingzeng, Chen Xing
1995, (1): 85-89.
In general, forward directed ice force is only considered by the designer.But experiments prove that the lateral ice force caused by the uneven contact between ice sheet and the pile also exists.The lateral ice force does not object to normal or Gumbel distribution,and is not relevant to the forward directed one in numerical value.Preventive measures should be taken to avoid the damage caused by the lateral ice force to the structure in design phase.
Optimum fifth order Stokes wave theory
Fu Yuhua
1995, (1): 91-101.
This paper improves the existing fifth order Stokes wave theory by using least square method.and gives the optimum result in the meaning of minimum error squares to satisfy the free surface boundary conditions, and the wave profile can be adjusted according to the measured data.This paper also gives a simplified method for deriving the parameters of the existing fifth order Stokes wave.
The characteristic and prediction of scour in front of breakwaters by standing waves
Gao Xueping
1995, (1): 103-112.
In this paper bottom scours in front of vertical breakwaters by standing waves are systematically inves-tigated, the scouring patterns, criterion for differentiating the scouring patterns and scouring mechanism are discussed; a formula of maximum depth of scouring trough considering sediment size is given; and influence of mound foundation on bottom scours is investigated.
Second sea-entering approach of Changjiang River: Tonglü Canal-planning of control dimensions, analysis of erosion and siltation and selection of outlet
Lu Wujiang, Jin Jianxin
1995, (1): 113-125.
Assume that the Tonglu Canal would be widened and deepened in which a water lock is constructed at the river side, and made open to the sea side.The canal's planned control dimensions are determined, and the erosion and siltation characteristics along the river (totally 81.8 km) are analyzed by the numerical calculation of one-dimensional unsteady flow and the relative standards.According to the data of the evolution, hydrology and sediment in the Xiaomiaohong Waterway, it is found reasonable to select the channel near the Xingang Gate as the second sea-entering approach.This paper is helpful in planning and designing the approach.
Notes Distribution of planktonic pyrrophyta in the East China Sea
Lin Jinmei
1995, (1): 127-134.
Chromosomal index of Ostreidae
Rong Shoubai
1995, (1): 135-139.
A comparative study on protein content and amino acid composition of eight species of Unicellular marine feed algae
Cao Shuli, Xiang Saoqing
1995, (1): 141-145.
A study of relationship between red tide formation and bacteria count in west waters of Xiamen Harbour
Zeng Huoshui, Lin Yanshun, Yao Ruimei
1995, (1): 147-153.