2000年  第19卷  第4期

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Adaptation strategy for sea level rise in vulnerable areas along China's coast
Du Bilan, Zhang Jinwen
2000, (4): 1-16.
摘要:
It can be seen from the calculation that the vulnerable area along China's mast in which the elevation is less than 5 m, is 143 900 km2,accounting for about 11.3% of the total area of the 11 coastal provinces, municipalities and autonomous regions.These areas are threatened to varying extent by sea level rise.
According to prediction, the relative sea level rise (including global sea level rise caused by climate change and local relative sea level rise caused by vertical crust movement and ground subsidence) along China's coast will be 4~16 cm by the year 2030 with the optimum estimated value of 6~14 cm.It will be 9~26 cm by the year 2050 with the optimum estimated value of 12~23 cm.And it will be 31-74cm by the year 2100 with the optimum estimated value of 47~65 cm.
The calculation result shows that the percentage of the cost for up-grading (heightening and consolidating) sea dykes/walls in adaptation strategy in the losses of submerged areas varies from area to area:6.90% in the Zhujiang (Pearl) River Delta, 1.3%~24.60% in the Changjiang (Yangtze) River Delta, and 0.9%~2.0% in the Huanghe River Delta.
Numerical solution of a mathematical model for water wavesin large coastal areas
Zheng Yonghong, Shen Yongming, Xia Jin
2000, (4): 17-23.
摘要:
on the evolution equation for water waves,a mathematical model for wave propagation in large mild-slope areas is derived.The model is solved by the finite difference method with the staggered grid system.The computational results are in good agreement with experimental data and show that the model can obtain better results with relatively coarser grids.The model can be used to simulate water wave propagation in large coastal areas and can be efficiently solved without much programming effort.
Upper-ocean variation in the northern South China Sea from mooring station observations
Fang Wendong, Shi Ping, Mao Qingwen, Gan Zijun
2000, (4): 25-35.
摘要:
STD temperature, salinity and ADCP current data, which were observed by R/V Shiyan No.3 during the intensive observational period (IOP) of the South China Sea monsoon experiment (SCSMEX),have been analyzed.Some study results from observations at a mooring station located at the vicinity of continental slope off the south of Dongsha Islands are shown.The dynamic and thermodynamic structures as well as their changes are analyzed to describe the upper-ocean variation in the northem South China Sea during the summer monsoon onset and maintaining periods.The response of near surface water temperature, salinity and current to local sea surface winds is also discussed.
Dispersion relation of internal waves in the western equatorial Pacific Ocean
Fang Xinhua, Jiang Mingshun, Du Tao
2000, (4): 37-45.
摘要:
Based mainly on TOGA COARE data, that is, the CI'D data from R/V Xiangyanghong No.5 (Pu et al.,1993),the temperature and current data from the Woods Hole mooring and other deep current data, the layered numerical profiles of buoyancy frequency and mean current components are figured out.A numerical method calculating internal wave dispersion relation without background shear current, used by Fliegel and Hunkins (1975),is improved to be fit for the internal wave equation with mean currents and their second derivatives.The dispersion relations and wave functions of the long crested internal wave progressing in any direction can be calculated inveniently by using the improved method.A comparison between the calculated dispersion relation in the paper and the dispersion relation in GM spectral model of ocean internal waves (Garret and Munk, 1972) is performed.It shows that the mean currents are important to the dispersion relation of internal waves in the western equatorial Pacific Ocean and that the currents make the wave progressing co-directional with (against) the currents stretched (shrink).The influence of the mean currents on dispersion relation is much stronger than that of their second derivatives, but that on wave function is less than that of their second derivatives.The influences on wave functions result in the change of vertical wavenumber, that is, making the wave function stretch or shrink.There exists obvious turning depth but no significant critical layer absorption is found.
Application of sequency spectral method to ocean and atmosphere data analysis
Zhang Shuwen, Sun Fu, Tian Jiwei, Zhou Faxiu
2000, (4): 47-52.
摘要:
The chaotic systems of average monthly air temperature of Qjngdao (SATQ) and the day SST of equatorial local area (DSSEI,A) are firstly studied by means of the sequency spectral method.It is shown that SATQ contains one-a period of predominant oscillation, two-a periods lower frequency oscillatian and 90-d, 63-d, 50-d, 40-d and 29-d lower frequency periods oscillation in D6SELA.Further-more, the discrepancies between sequency spectrum and frequency spectrum are compared in this paper.
An inverse method for underwater bottom topography by using SAR imagery
Jin Yaqiu, Zhang Wei
2000, (4): 53-62.
摘要:
Interaction between current and underwater bottom topography leads to roughness of the sea surface, which in turn yields variation of the radar scattering echo.By using the continuity equation and weak hydrodynamic interaction theory in the relaxation time approximation, the spatial variation of the radar scattering cross-section has been proved as proportional to the gradient of current velocity.The current direction is first determined by using two-dimensional (2-D) correlation of spatial variation of backscattering measured by the SAR imagery, as the priori knowledge of the current direction is not available.The inverse algorithm to successively derive 2-D underwater bottom topography from the SAR imagery is developed.As an application, the SAR SIR-C image over the sea area of Hong Kong, China is studied.
Study on chemical forms of fluorine enrichment of Antarctic krill
Pan Jianming, Zhang Haisheng, Liu Xiaoya
2000, (4): 63-72.
摘要:
The different forms fluorine in different parts of molting process of krill was analyzed by culture of Antarctic krill (Euphausia superba).The results show that fluorine amount in cuticle is up to 90% of total in the krill.During the krill molting process, the fluorine content in cuticle and muscle varies alternatively.This is to say, the fluorine content in new cuticle and muscle is much lower after molted, the fluorine in krill comes from seawater by biological absorption of the krill, and the fluorine absorbed by krill lost with the old cuticle at the end stage of molting process.Meanwhile, the new molting process starts again.The evidence is proved by the change of different fomls fluorine content in cuticle and muscle during krill's molting process.At last the author proposes the fluorine enriching process model of Antarctic krill.
Helium and Oxygen isotopic evidence on exchange of waters between the western Pacific Ocean and the South China Sea
Ren Jianguo, Wang Xianbin
2000, (4): 73-79.
摘要:
The composition and distribution of helium and oxygen isotopes in samples of seawater obtained at depths from surface to 300 m in the western Pacific(7°-26°N,122°-130°E) were discussed in detail.The results show that both δ18O and δ3He isoline extend eastward in the Pacific side of the Bashi Channel, which may suggest that the South China Sea water intrudes into the western Pacific by the Bashi Channel.
A preliminary study on benthos food web structure of tidal zone in the Laoshan Bay by using stable carbon isotopes
Cai Deling, Hong Xuguang, Mao Xinghua, Zhang Shufang, Gao Sulan
2000, (4): 81-89.
摘要:
By analyses of carbon isotopic composition(δ13C values) of the benthos collected in the Laoshan Bay in August 1993 and February and May 1994, it is found that the main food sources of the benthos can be divided into four groups in terms of carbon isotope composition:Particulate Organic Matter (POM),benthic diatoms, benthic macroalgae and the organic matter in sediments.The results show that the carbon isotopic composition of the benthic animals has a close relation with that of the food they take in.The carbon isotopic compositions of benthos may be useful in elucidating their food sources.The carbon isotopic data have confirmed that POM is the main food source of the benthic filter feeders such as bivalves; crustaceans have a wide range of δ13C values, showing their food source has diversity; benthic diatoms are an important fraction of the food for most of gastropods.A preliminary investigation of the benthic-pelagic coupling in that region using the stable carbon isotopic tracers has confirmed the importance of POM as a food source for benthos in this region,but the organic matter in sediments and benthic diatoms are also relatively important for a lot of benthic animals.The benthic-pelagic coupling in the Laoshan Bay temperate ecosystem is not so tight as that in ecosystems at higher latitudes such as north-eastern water polynya.
Basin assemblages and tectonic evolution in the Bohai Gulf and its neighbors
Li Sanzhong, Xu Shumei, Shan Yehua, Li Xishuang, Zhou Lihong, Hao Yinquan, Fan Zheqing, Liang Huilan
2000, (4): 91-105.
摘要:
According to multi-disciplinary research advances in recent years, three blocks which named Jiaoliao-Bohai block, central North China block and Ordos block are divided.The differences of the tectonic association, types, styles and features in the space, and ewlution fmm Archaean to Cenozoic in the time, between the former two blocks are discussed.Tectonic features and evolution in the four tectonic stages of Precambrian, Indo-China, Yanshanian and Cenozoic are emphasized especially here.All of them described above have inherit and neogenic property.The temporal-spatial change and interaction among basin assemblages in the above four stagers are analyzed.Escape tectonic model is employed to interpret coeval compressive and extensional basins in the study area.
A preliminary study on diatoms and silicoflagellates in cores from CC Zone, the East Pacific
Lan Dongzhao, Chen Chenghui
2000, (4): 107-116.
摘要:
After analyzing the diatoms and silicoflagellates in Core 1787 of east area and Core 2437 of west area from CC Zone, the East Pacific, 31 genus and 81 species and varieties of diatom and 7 genus and 12 species of silicoflagellates are identified.There are 8 diatom canes in Core 1787 and 1 diatom zone in Core 2437.According to the characteristics of diatom zones and the occurring and extinct ages of some diatom and silicoflagellate species, the strata since Oligocene in the region are subdivided.Lastly,combined with the data of radiolarians and paleomagnetism,some problems for Core 1787 are discussed, including where is the lower boundary of Quaternary, whether Pliocene is absent or not and whether Oligocene is present or not.
Minicistron from a gene of prawn white spot bacilliform virus (WSBV) and its expression
Zhang Xiaobo, Xu Xun, Yang Feng
2000, (4): 117-123.
摘要:
By the sequencing and analysis of genomic DNA and cDNA of WSBV, it was found that these existed a minicistnni in the leading sequence of p204 gene.The minicistron utilized rare oodons of genes from prawn and WSBV.The p204 gene could be expressed in Escherichia coli whether a miniciston exited in its leading sequence or not, but the amounts of the expressed products of them were different.The minicistron might be related to the expression of p204 gene.
Fish species diversity in the Huanghe Estuary
Chen Dagang, Jiao Yan, Liu Qun, Zeng Xiaoqi, Ren Yiping
2000, (4): 125-135.
摘要:
This paper lists 50 fish species in the Huanghe Estuary, which belong to 9 orders, 22 families and 37 genera.The paper describes the seasonal distributions of these fish species and the succession of the importan fish species during the past 50 a.The anthors discuss the main factors that have resulted in the changes in fish species diversity and the fishery resources.These include the overexploitation of the fishery and the sharp reduction in the fresh water discharges from the Huanghe River.
Phytoneuston in the southern Taiwan Strait
Huang Jiaqi, Li Shaojing, Yu Yao
2000, (4): 137-146.
摘要:
In June and November 1988 samples were collected by the improved Manta neuston net at 18 stations in the southern Taiwan Strait.One hundred and two species and variations of phytoneuston are identified.Total individuals of phytoneuston in June are more than those in November.The horiwntal distribution of phytoneuston is that the dense area occurs in the southern Taiwan Bank in June, while it appears in the western Taiwan Bank in November.The diet variations of phytoneuston are very obvious.The.abundance of phytoneuston occurs in the afternoon (16:00),and the minimum at midnight which is opposite to zooneuston.The relationships between phytoneuston and environment, and between phytoneuston and zooneuston are also discussed.