2000 Vol. 19, No. 2
Display Method:
2000, (2): 1-6.
Abstract:
The Hessian matrix,which is formed by the second-order partial derivatives of the cost function with respect to control variables,plays an important role in the procedure of variational data assimilation(VDA),sensitivity analysis,etc.,and it can be obtained by establishing the first-order adjoint(FOA) and the second-order adjoint(SOA) models for direct model.The derivations of the FOA and SOA models of shallow water equations model are given in detail,which is based upon the Crateaux differential of funcFional and the concepts of the adjoint operators in Hilbert space.The result for SOA model of the shallow water equations model is obtained,which improves the theory established in the paper of Wang et al.(1992).
The Hessian matrix,which is formed by the second-order partial derivatives of the cost function with respect to control variables,plays an important role in the procedure of variational data assimilation(VDA),sensitivity analysis,etc.,and it can be obtained by establishing the first-order adjoint(FOA) and the second-order adjoint(SOA) models for direct model.The derivations of the FOA and SOA models of shallow water equations model are given in detail,which is based upon the Crateaux differential of funcFional and the concepts of the adjoint operators in Hilbert space.The result for SOA model of the shallow water equations model is obtained,which improves the theory established in the paper of Wang et al.(1992).
2000, (2): 7-18.
Abstract:
The temporal variations and geographical distributions of sensible and latent heat fluxes over the Pacific were calculated and analyzed by using the Goddard Earth Observing System(GEOS) four-dimensional Data Assimilation System(DAS).The calculated results showed that the heat flux over the northwestern Pacific varied obviously with seasons,but over the other ocean areas of the Pacific Ocean there were no such phenomena.There was always the highest value region of latent heat fluxes over the Pacific Ocean,but the values of sensible heat fluxes were often very small except over the ocean area north of 20°N and there was not highest value region at all.The latent heat fluxes had different distributions with longitude in different latitudes.And the variations of latent heat fluxes with latitude were not the same in different longitude and also it varied with seasons.
The temporal variations and geographical distributions of sensible and latent heat fluxes over the Pacific were calculated and analyzed by using the Goddard Earth Observing System(GEOS) four-dimensional Data Assimilation System(DAS).The calculated results showed that the heat flux over the northwestern Pacific varied obviously with seasons,but over the other ocean areas of the Pacific Ocean there were no such phenomena.There was always the highest value region of latent heat fluxes over the Pacific Ocean,but the values of sensible heat fluxes were often very small except over the ocean area north of 20°N and there was not highest value region at all.The latent heat fluxes had different distributions with longitude in different latitudes.And the variations of latent heat fluxes with latitude were not the same in different longitude and also it varied with seasons.
2000, (2): 19-27.
Abstract:
The specific activities of 224Ra,226Ra and 228Ra were determined by measuring γ-rays of their daughters with HPGe γ spectrometer after preconcentrating Ra isotope' with Mn-fiber adsorption from large volume seawater.The calculating formulas of specific activities of the three nuclides derived.The methods of sample preparation and spectnun analysis were discussed.The advantages of the method are simple,rapid and three nuclides can be determined simultaneously.
The specific activities of 224Ra,226Ra and 228Ra were determined by measuring γ-rays of their daughters with HPGe γ spectrometer after preconcentrating Ra isotope' with Mn-fiber adsorption from large volume seawater.The calculating formulas of specific activities of the three nuclides derived.The methods of sample preparation and spectnun analysis were discussed.The advantages of the method are simple,rapid and three nuclides can be determined simultaneously.
2000, (2): 29-35.
Abstract:
Alkaline phosphatase activity(APA) and dissolved phosphonis were monitored during the batch cultures of two marine microalgae.Results indicate that variation of APA was in the shape of "S" curve.Different species of dissolved phosphorus had different effects on APA.The concentrations of dissolved inorganic phosphorus(DIP) and small molecular dissolved organic phosphorus(SDOP) had a significant effect on APA,while the concentration of large molecular dissolved organic phosphorus(LDOP) had a little effect on APA.,and the increase of APA could accelerate the decotrtposing of LDOP in the medium.Results also show that algae species and abundance had only a little effect on APA.
Alkaline phosphatase activity(APA) and dissolved phosphonis were monitored during the batch cultures of two marine microalgae.Results indicate that variation of APA was in the shape of "S" curve.Different species of dissolved phosphorus had different effects on APA.The concentrations of dissolved inorganic phosphorus(DIP) and small molecular dissolved organic phosphorus(SDOP) had a significant effect on APA,while the concentration of large molecular dissolved organic phosphorus(LDOP) had a little effect on APA.,and the increase of APA could accelerate the decotrtposing of LDOP in the medium.Results also show that algae species and abundance had only a little effect on APA.
2000, (2): 37-44.
Abstract:
The spatial and temporal distributions of new production vary largely in different sea area.To understand the level of new production in the sea area studied better,an estimate of new production must be obtained in large spatial and temporal scales.The 234Th-238U disequilibrium is an effective method for the study of new production.Two sampling strategies,vertically integrated sampling approach based on trapewidal integration principle and discrete layer sampling approach,Two compared in the studies of the Xiamen Bay and the northern South China Sea.The scavenging fluxes and removal fluxes of 234Th and the residence times for dissolved and particulate 234Th were calculated.The coincident results from two sampling approach suggest that vertically integrated sampling approach is not only effective and reliable,but also significantly reduces the number and volume of samples.It allows us to study new production by 234Th-238U disequiiibria in large spatial scale.
The spatial and temporal distributions of new production vary largely in different sea area.To understand the level of new production in the sea area studied better,an estimate of new production must be obtained in large spatial and temporal scales.The 234Th-238U disequilibrium is an effective method for the study of new production.Two sampling strategies,vertically integrated sampling approach based on trapewidal integration principle and discrete layer sampling approach,Two compared in the studies of the Xiamen Bay and the northern South China Sea.The scavenging fluxes and removal fluxes of 234Th and the residence times for dissolved and particulate 234Th were calculated.The coincident results from two sampling approach suggest that vertically integrated sampling approach is not only effective and reliable,but also significantly reduces the number and volume of samples.It allows us to study new production by 234Th-238U disequiiibria in large spatial scale.
2000, (2): 45-55.
Abstract:
By using satellite remote sensing informations,the conceptual system of time-space attributes and time dimension in recent evolution of the sand spit at the Huanghe River mouth is expounded.Based on this work,the parameterization of relevant factors and topological analysis of sand spit spatial structure are conducted,and a model,which is suitable for representing the development and growth of the Huanghe River mouth is developed.It is slbwn that during the later stage of its development,the sand spit growth index is almost 0.According to the parallelogram rule,under the reinforce effects of the Coriolis force and ocean dynamics,the sand spit of current stream will never extend towards sea when it reaches the deep-water area.This work would be helpful to the imminent comprehensive harness of the "man-made river branch" at the Huanghe River mouth.
By using satellite remote sensing informations,the conceptual system of time-space attributes and time dimension in recent evolution of the sand spit at the Huanghe River mouth is expounded.Based on this work,the parameterization of relevant factors and topological analysis of sand spit spatial structure are conducted,and a model,which is suitable for representing the development and growth of the Huanghe River mouth is developed.It is slbwn that during the later stage of its development,the sand spit growth index is almost 0.According to the parallelogram rule,under the reinforce effects of the Coriolis force and ocean dynamics,the sand spit of current stream will never extend towards sea when it reaches the deep-water area.This work would be helpful to the imminent comprehensive harness of the "man-made river branch" at the Huanghe River mouth.
2000, (2): 57-67.
Abstract:
Geotechnical data obtained from the polymetallic nodules investigation in 1994,in combination with the historical data concerned,are analyzed comprehensively to study sediment types,geotechnical properties,soil strength and so on,in order to provide bases for design and construction of engineering facilities and the equipments required for the polymetallic nodules nuning in the future.
Geotechnical data obtained from the polymetallic nodules investigation in 1994,in combination with the historical data concerned,are analyzed comprehensively to study sediment types,geotechnical properties,soil strength and so on,in order to provide bases for design and construction of engineering facilities and the equipments required for the polymetallic nodules nuning in the future.
2000, (2): 69-81.
Abstract:
On the basis of the investigation materials of 6 cruises in the waters north of Taiwan from 1987-1990,the distribution characteristics of planktonic copepods are discussed in the study from three aspects of abundance distribution,community feature and indicative species.The paper is the first part of the study.The results show as follows:the highest abundance of copepods occurred in spring and the lowest one in winter,while the abundance in summer and autumn was between the above two seasons.The copepod abundance in the west of the Kuroshio front was higher than that in the east of the front.There was a distribution tendency that higher abundance occurred in outshore area in summer and in nearshore area in winter,which corresponded with the trend of seasonal swings of the Kuroshio front.The higher copepod abundance appeared generally in the mixed areas of various water masses,especially in nearshore side of upwelling of the Kuroshio sub-surface water.However,in the Kuroshio subsurface main water,the abundance was low because of some factors such as low concentration of dissolved oxygen and so on.The vertical distribution trend was that the copepod abundance decreased with the increase of depth,and the diurnal vertical migration regularities of some species were probably the one of reasons that caused the abnormal distributions in some local waters.
On the basis of the investigation materials of 6 cruises in the waters north of Taiwan from 1987-1990,the distribution characteristics of planktonic copepods are discussed in the study from three aspects of abundance distribution,community feature and indicative species.The paper is the first part of the study.The results show as follows:the highest abundance of copepods occurred in spring and the lowest one in winter,while the abundance in summer and autumn was between the above two seasons.The copepod abundance in the west of the Kuroshio front was higher than that in the east of the front.There was a distribution tendency that higher abundance occurred in outshore area in summer and in nearshore area in winter,which corresponded with the trend of seasonal swings of the Kuroshio front.The higher copepod abundance appeared generally in the mixed areas of various water masses,especially in nearshore side of upwelling of the Kuroshio sub-surface water.However,in the Kuroshio subsurface main water,the abundance was low because of some factors such as low concentration of dissolved oxygen and so on.The vertical distribution trend was that the copepod abundance decreased with the increase of depth,and the diurnal vertical migration regularities of some species were probably the one of reasons that caused the abnormal distributions in some local waters.
2000, (2): 83-88.
Abstract:
Somatic cells were prepared from sea snail enzyme digests of Porphyra yezoensis thalli.Using SDS-Proteinase K as extraction solution,total DNA was isolated from the somatic cells.The crude extracts of total DNA were purified with glassmilk,and the resulting DNA was of sufficient quality for digestion of restriction endonuclease.DNA bands were clearly observed in the restriction patterns of EcoRI,PstI and HaeⅢ respectively.The presence of DNA bands in the restriction pattern of total DNA indicated that the genome of Porphyra yezoensis may be small.Unexpectedly,using guanidinium isothiocyanate and sarcosyl as extraction solution,a plasmid-like DNA band(2.3 Kb) was directly found in the isolated total DNA of Porphyra yezoensis.A very simple and convenient method for plasmid-like DNA isolation has been established.
Somatic cells were prepared from sea snail enzyme digests of Porphyra yezoensis thalli.Using SDS-Proteinase K as extraction solution,total DNA was isolated from the somatic cells.The crude extracts of total DNA were purified with glassmilk,and the resulting DNA was of sufficient quality for digestion of restriction endonuclease.DNA bands were clearly observed in the restriction patterns of EcoRI,PstI and HaeⅢ respectively.The presence of DNA bands in the restriction pattern of total DNA indicated that the genome of Porphyra yezoensis may be small.Unexpectedly,using guanidinium isothiocyanate and sarcosyl as extraction solution,a plasmid-like DNA band(2.3 Kb) was directly found in the isolated total DNA of Porphyra yezoensis.A very simple and convenient method for plasmid-like DNA isolation has been established.
2000, (2): 89-95.
Abstract:
In China,the total annual production of cultured Laminaria japonica reached half million tons in dry weight these few years.The routine sporeling culture technique conducted in the greenhouse took aF least three and half months.In such a case,sometimes the sporelings died within a few days due to destructive diseases.In order to overcome the mentioned problems,a new sporeling culture technique,the clone technique,is developed.The method includes three steps:(1)Gametophyte clone culture.The spores and the gametophytes are cloned in flasks under favorable environments.(2) Sporeling cultore.Male and female clones are crushed and spread onto a frame to allow the gametophytes to attach to the substrata.The frames are cultured in tanks,and the sporophytes reach 1 cm in length within one and a half months.(3) Outgrowing of the plant.The frames are put in the open sea when seawater temperature decreased to 20℃.After one month,the sporelings are large enough to be transplanted.It is concluded that the clone technique has the following advantages:(1) Large amount of clones can be produced in a short period of time.(2) Clone seeding method makes it free from the biological rhythm.one can seed the plant anytime all the year round.(3) It takes only one and a half months to complete the process of sporeling cultivation in the greenhouse.At present,this technique is used in the breeding of new strains of Laminoria.
In China,the total annual production of cultured Laminaria japonica reached half million tons in dry weight these few years.The routine sporeling culture technique conducted in the greenhouse took aF least three and half months.In such a case,sometimes the sporelings died within a few days due to destructive diseases.In order to overcome the mentioned problems,a new sporeling culture technique,the clone technique,is developed.The method includes three steps:(1)Gametophyte clone culture.The spores and the gametophytes are cloned in flasks under favorable environments.(2) Sporeling cultore.Male and female clones are crushed and spread onto a frame to allow the gametophytes to attach to the substrata.The frames are cultured in tanks,and the sporophytes reach 1 cm in length within one and a half months.(3) Outgrowing of the plant.The frames are put in the open sea when seawater temperature decreased to 20℃.After one month,the sporelings are large enough to be transplanted.It is concluded that the clone technique has the following advantages:(1) Large amount of clones can be produced in a short period of time.(2) Clone seeding method makes it free from the biological rhythm.one can seed the plant anytime all the year round.(3) It takes only one and a half months to complete the process of sporeling cultivation in the greenhouse.At present,this technique is used in the breeding of new strains of Laminoria.
2000, (2): 97-110.
Abstract:
Based on the data of the Jiaozbou Bay Ecosystem Dynamic Research,cell volume and surface area of 87 common phytoplankton species in China sea waters were calculated with assignment of the similar geometric form.The cell plasma volume,live weight,carbon mntent and nitrogen content were also calculated with the methods of Mullin et al.(1966),5trathmann(1967),Eppley et al.(1970),arid Taguchi(1976).After comparing these methods,we chose the method of Eppley et al.(1970) as the best method for calculating phytoplankton carbon content in China sea waters.
Based on the data of the Jiaozbou Bay Ecosystem Dynamic Research,cell volume and surface area of 87 common phytoplankton species in China sea waters were calculated with assignment of the similar geometric form.The cell plasma volume,live weight,carbon mntent and nitrogen content were also calculated with the methods of Mullin et al.(1966),5trathmann(1967),Eppley et al.(1970),arid Taguchi(1976).After comparing these methods,we chose the method of Eppley et al.(1970) as the best method for calculating phytoplankton carbon content in China sea waters.
2000, (2): 111-125.
Abstract:
Comparisons of wave reflection,transmission and harmonics due to different types of submerged structures are investigated by a numerical method,the boundary-fitted coordinate(BFC) method.The types of submerged structures include a submerged horizontal plate,submerged breakwatern(rectangular and trapezoidal) and a step-type structure(topography).First,the BFC method is verified by comparing the computed results with the experimental data,including wave surface elevations,reflected and transmitted wave heights,and amplitudes of higher harmonics,showing that the method is a reasonable one to predict wave deformations due to the submerged structures.Secondly,the wave surface elevations and the higher harmonics over different submerged structures are compared.Thirdly,reflected and transmitted waves due to different submerged structures are investigated.
Comparisons of wave reflection,transmission and harmonics due to different types of submerged structures are investigated by a numerical method,the boundary-fitted coordinate(BFC) method.The types of submerged structures include a submerged horizontal plate,submerged breakwatern(rectangular and trapezoidal) and a step-type structure(topography).First,the BFC method is verified by comparing the computed results with the experimental data,including wave surface elevations,reflected and transmitted wave heights,and amplitudes of higher harmonics,showing that the method is a reasonable one to predict wave deformations due to the submerged structures.Secondly,the wave surface elevations and the higher harmonics over different submerged structures are compared.Thirdly,reflected and transmitted waves due to different submerged structures are investigated.
2000, (2): 127-136.
Abstract:
A systematic study of waves,nearshore currents and sediment transport related to the coastal evolution of sand beach under the action of wave,has been carried out.On the basis of the resalts,a numerical model of sand beach evolution around coastal structures has been established.To predict the bed topography,the sediment transport rates of bedload and suspended load under the action of wave and nearshore current as well as the effects of wave on the sediment are wnsidered.The sand beach evolutions caused by a breakwater and a settled ship near the shore are simulated.
A systematic study of waves,nearshore currents and sediment transport related to the coastal evolution of sand beach under the action of wave,has been carried out.On the basis of the resalts,a numerical model of sand beach evolution around coastal structures has been established.To predict the bed topography,the sediment transport rates of bedload and suspended load under the action of wave and nearshore current as well as the effects of wave on the sediment are wnsidered.The sand beach evolutions caused by a breakwater and a settled ship near the shore are simulated.
2000, (2): 137-144.
Abstract:
Based on N-S equations,the depth-averaged stress-flux algebraic model is used to simulate the anisotropic transport and dispersion when hot water or pollutants are side-discharged into large water body.In this model the depth-averaged continuity,momentum and concentration equations are employed,and the tide is asymmetric.The results show the changes of velocity field and pollutant concentration With time and space during one tidal period.
Based on N-S equations,the depth-averaged stress-flux algebraic model is used to simulate the anisotropic transport and dispersion when hot water or pollutants are side-discharged into large water body.In this model the depth-averaged continuity,momentum and concentration equations are employed,and the tide is asymmetric.The results show the changes of velocity field and pollutant concentration With time and space during one tidal period.
2000, (2): 145-152.
Abstract:
