2004 Vol. 26, No. 1
Display Method:
2004, 26(1): 1-13.
Abstract:
On the basis of hydrographic data obtained in August 2000 cruise,the circulation in the South China Sea (SCS)is computed by using the modified inverse method in combination with SSH data from TOPEX/ER S-2 Analysis.The following results have been obtained.(1)The central and southw estern SCSs are dominated mainly by anticyclonic circulation systems.They are mainly as follows.1)There is strong anticyclonic eddy southeast of Vietnam(W1).Its horizontal scale is about 300 km,and it extends vertically from the surface to the 1 000 m more than.It is very strong with a Vmax of about 79 cm/s;2)there are a warm eddy W2 and the anticyclonic circulation system W3 west off the Philippines.In the next place,there is a stronger cyclonic eddy C1 between the anticy clonic eddies W1 and W2,and it is also strong.A southward flow exists between the eddies W1 and C1.The eddies W1 and C1 compose a quasi-dipole.(2)A strong coastal jet is present at the western boundary west of an anticy clonic eddy W1,and the jet flows northward and separates from the coast of Vietnam at about 12°N to the northeast.
On the basis of hydrographic data obtained in August 2000 cruise,the circulation in the South China Sea (SCS)is computed by using the modified inverse method in combination with SSH data from TOPEX/ER S-2 Analysis.The following results have been obtained.(1)The central and southw estern SCSs are dominated mainly by anticyclonic circulation systems.They are mainly as follows.1)There is strong anticyclonic eddy southeast of Vietnam(W1).Its horizontal scale is about 300 km,and it extends vertically from the surface to the 1 000 m more than.It is very strong with a Vmax of about 79 cm/s;2)there are a warm eddy W2 and the anticyclonic circulation system W3 west off the Philippines.In the next place,there is a stronger cyclonic eddy C1 between the anticy clonic eddies W1 and W2,and it is also strong.A southward flow exists between the eddies W1 and C1.The eddies W1 and C1 compose a quasi-dipole.(2)A strong coastal jet is present at the western boundary west of an anticy clonic eddy W1,and the jet flows northward and separates from the coast of Vietnam at about 12°N to the northeast.
2004, 26(1): 14-24.
Abstract:
Using the two CTD data of the summertime in 2000 and wintertime in 2001 in the Bohai Sea,the temperature,salinity and density distributional characteristics of the wintertime and summer time in the Bohai Sea are analysed systemically and it is revealed that the current hydrologic characteristics of the Bohai Sea have some new phenomena compared with the previous research results.In summer there are three low temperature centers in the middle layer and underlayer of the middle parts of the Bohai Straits,the Liaodong Gulf mouth and the Bohai Gulf mouth but there is a uniform high temperature center in the middle Bohai Sea.In winter the isotherms extend westward and northward to the Bohai Sea from the warm core of the Bohai Straits and the cold water tongue off the Qinhuangdao spreads southeastward out,so the saddle like isotherm pattern is formed in the middle Bohai Sea.The salinity in the Bohai Sea in summer and winter rises significantly compared with the previous results and is higher than the northwestern Huanghai Sea.The salinity distribution characteristics are the high salinity in the Bohai Bay and the low salinity in the Bohai Straits.The density distribution shows that in summer there is a large cyclonic density circulation in the Bohai Sea and it is likely to exist some density current eddies in the middle part.In winter the saddle like pattern of the Bohai Sea temperature and salinity shows that the circulation structure is much complexer than the previous research results.The Huanghai Sea Warm Current(extension)has branches in the Bohai Sea.The model diagnostic results of the thermohaline residual currents accord well with the observed data.
Using the two CTD data of the summertime in 2000 and wintertime in 2001 in the Bohai Sea,the temperature,salinity and density distributional characteristics of the wintertime and summer time in the Bohai Sea are analysed systemically and it is revealed that the current hydrologic characteristics of the Bohai Sea have some new phenomena compared with the previous research results.In summer there are three low temperature centers in the middle layer and underlayer of the middle parts of the Bohai Straits,the Liaodong Gulf mouth and the Bohai Gulf mouth but there is a uniform high temperature center in the middle Bohai Sea.In winter the isotherms extend westward and northward to the Bohai Sea from the warm core of the Bohai Straits and the cold water tongue off the Qinhuangdao spreads southeastward out,so the saddle like isotherm pattern is formed in the middle Bohai Sea.The salinity in the Bohai Sea in summer and winter rises significantly compared with the previous results and is higher than the northwestern Huanghai Sea.The salinity distribution characteristics are the high salinity in the Bohai Bay and the low salinity in the Bohai Straits.The density distribution shows that in summer there is a large cyclonic density circulation in the Bohai Sea and it is likely to exist some density current eddies in the middle part.In winter the saddle like pattern of the Bohai Sea temperature and salinity shows that the circulation structure is much complexer than the previous research results.The Huanghai Sea Warm Current(extension)has branches in the Bohai Sea.The model diagnostic results of the thermohaline residual currents accord well with the observed data.
2004, 26(1): 25-32.
Abstract:
Effect of centrifugal rotational speed on desalination and factors exceeded quality standard of gay-white ice in the Bohai Sea were studied by centrifugal experiments at the laboratory.The experimental results show that the effect of rotational speed variance on the desalination and its efficiency are obvious under the same experiment condition.When the rotational speed arrived at 2 000 r/min,the total salt of the desalted ice decreased basically to the standard value.The rate of desalination of gray-white ice in the Bohai Sea maintained higher level and commonly surpassed 80%~90%.When the centrifugal rotational speed was 3 000~4 000 r/min,the rate of desalination of gray-white ice in the Bohai Sea was maximum and its value was 90.96%.The removal of materials exceeded standard from gray-white ice was influenced in varying degrees by the variations in the centrifugal rotational speed. The sulfate content changed maximally and decreased by 73.19%~96.52%.The salinity also more decreased and had less decreased range than sulfate,the range was 71.86%~93.55%.pH value was not deteriorative after desalination and it maintained about 715.Therefore centrifugal rotational speed is one of major controlling parameters in the centrifugal desalting process of gray-white ice in the Bohai Sea.After gray-white ice in the Bohai Sea were desalted,such quality factors as salinity of desalted ice fulfil the needs of water for the industry and agriculture production and the people's living.
Effect of centrifugal rotational speed on desalination and factors exceeded quality standard of gay-white ice in the Bohai Sea were studied by centrifugal experiments at the laboratory.The experimental results show that the effect of rotational speed variance on the desalination and its efficiency are obvious under the same experiment condition.When the rotational speed arrived at 2 000 r/min,the total salt of the desalted ice decreased basically to the standard value.The rate of desalination of gray-white ice in the Bohai Sea maintained higher level and commonly surpassed 80%~90%.When the centrifugal rotational speed was 3 000~4 000 r/min,the rate of desalination of gray-white ice in the Bohai Sea was maximum and its value was 90.96%.The removal of materials exceeded standard from gray-white ice was influenced in varying degrees by the variations in the centrifugal rotational speed. The sulfate content changed maximally and decreased by 73.19%~96.52%.The salinity also more decreased and had less decreased range than sulfate,the range was 71.86%~93.55%.pH value was not deteriorative after desalination and it maintained about 715.Therefore centrifugal rotational speed is one of major controlling parameters in the centrifugal desalting process of gray-white ice in the Bohai Sea.After gray-white ice in the Bohai Sea were desalted,such quality factors as salinity of desalted ice fulfil the needs of water for the industry and agriculture production and the people's living.
2004, 26(1): 33-39.
Abstract:
Based on the monthly mean SST data on 2 latitude multiplied by 2 longitude grid in the Pacific Ocean during 1950~2000,the zonal movement of surface warm water in the western Pacific warm pool in the equatorial Pacific band(5°N~5°S)was analyzed by using the Morlet wavelet transfor mation method.The results show that the maximum zonal movement range of surface warm water in the warm pool is 115 longitudes,and the eastern boundary of the surface warm water is of most striking interannual(2~8 a)and interdecadal(10~16 a)changes.The zonal movement of surface warm water in the warm pool underwent a climatic jump in about 1982,and as against cefore the jump,the eastern boundary of the surface warm water had migrated eastwards by 10 longitudes.Besides, the zonal movement of surface warm water in the warm pool plays a direct part in the formation and development of ENSO.
Based on the monthly mean SST data on 2 latitude multiplied by 2 longitude grid in the Pacific Ocean during 1950~2000,the zonal movement of surface warm water in the western Pacific warm pool in the equatorial Pacific band(5°N~5°S)was analyzed by using the Morlet wavelet transfor mation method.The results show that the maximum zonal movement range of surface warm water in the warm pool is 115 longitudes,and the eastern boundary of the surface warm water is of most striking interannual(2~8 a)and interdecadal(10~16 a)changes.The zonal movement of surface warm water in the warm pool underwent a climatic jump in about 1982,and as against cefore the jump,the eastern boundary of the surface warm water had migrated eastwards by 10 longitudes.Besides, the zonal movement of surface warm water in the warm pool plays a direct part in the formation and development of ENSO.
2004, 26(1): 40-47.
Abstract:
According to tw o 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 distinct lower than that in winter,and average 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,and average 0.12 μmol/dm3 in summer and 0.04 μmol/dm3 in winter respectively.The season change of total phosphor us is similar to phosphate,and average 0.22 μmol/dm3 in summer and 0.61 μmol/dm3 in winter respectively.In vertical direction,phosphate, TDP,and TP content is lowest in the upper 50 m water column,and increases linearly rapidly with water depth, increases slowly under 500 m,reaches to maximum about 1 000 m,then decreases slightly with water depth increasing.The vertical distribution is typical in summer,and there is small dispersion for phosphorus concentration for the same depth of different stations.However,in winter there is a large dispersion for phosphate,TDP,and TP,specifically for phosphate at 200 m at which the concentration is maximum.This result indicates that there is large difference in hydrology and biology condition that affect largely on the chemical environment of the South China Sea.The organic phosphorus is the predominant in the surface seawater of the South China Sea,but the inorganic phosphorus is the predominant in layers more than 150 m.The organic phosphorus concentration in deep water usually decreases with water depth increasing.The organic phosphorus in summer is distinct more than that in winter because of the strong biology activities in summer.
According to tw o 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 distinct lower than that in winter,and average 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,and average 0.12 μmol/dm3 in summer and 0.04 μmol/dm3 in winter respectively.The season change of total phosphor us is similar to phosphate,and average 0.22 μmol/dm3 in summer and 0.61 μmol/dm3 in winter respectively.In vertical direction,phosphate, TDP,and TP content is lowest in the upper 50 m water column,and increases linearly rapidly with water depth, increases slowly under 500 m,reaches to maximum about 1 000 m,then decreases slightly with water depth increasing.The vertical distribution is typical in summer,and there is small dispersion for phosphorus concentration for the same depth of different stations.However,in winter there is a large dispersion for phosphate,TDP,and TP,specifically for phosphate at 200 m at which the concentration is maximum.This result indicates that there is large difference in hydrology and biology condition that affect largely on the chemical environment of the South China Sea.The organic phosphorus is the predominant in the surface seawater of the South China Sea,but the inorganic phosphorus is the predominant in layers more than 150 m.The organic phosphorus concentration in deep water usually decreases with water depth increasing.The organic phosphorus in summer is distinct more than that in winter because of the strong biology activities in summer.
2004, 26(1): 48-61.
Abstract:
The Huanghe(Yellow)River course shifted from entering the northern Huanghai(Yellow)Sea to entering the southern Huanghai Sea at the northern part of North Jiangsu Province approximately in 9 600 a BP and continued to enter the southern Huanghai Sea to 8 500 a BP.The river mouth was some 100 km distance from north of the Changjiang River mouth.The huge sediments carried by the two large rivers made the Huanghe River-Changjiang River compound delta to be formed in this period.Then,the Huanghe River shifted to north and entered the Bohai Sea.This is inferred with the following facts:southw ard bending of the isopach of the postglacial marine sediments of the nearshore depocenter in the southern Huanghai Sea,the sedimentary sequences of drill hole QC4 and some sections,and the characteristics of the coastal ridges in North Jiangsu Province.These coastal ridges are mostly composed of non-biogenic fine and middle sands.It is much different from composition of the shell ridges being mainly composed of molluscan shells and their fragments on the west coast of the Bohai Sea,where is the abandoned Huanghe River Delta area.In 8 500~7 000 a BP,the west coastline of the Bohai Sea retreated for tens kilometers,the Huanghe River channel free shifted and the fine sediments carried into the Bohai Sea by the Huanghe River were resuspended,transported and reworked into the shallow marine deposits.The Huanghe River subaqueous delta could not be formed in this period.The Holocene Huanghe River Delta has been formed since 7 000 a BP, when the sea level rise decelerated and close to the stable level.
The Huanghe(Yellow)River course shifted from entering the northern Huanghai(Yellow)Sea to entering the southern Huanghai Sea at the northern part of North Jiangsu Province approximately in 9 600 a BP and continued to enter the southern Huanghai Sea to 8 500 a BP.The river mouth was some 100 km distance from north of the Changjiang River mouth.The huge sediments carried by the two large rivers made the Huanghe River-Changjiang River compound delta to be formed in this period.Then,the Huanghe River shifted to north and entered the Bohai Sea.This is inferred with the following facts:southw ard bending of the isopach of the postglacial marine sediments of the nearshore depocenter in the southern Huanghai Sea,the sedimentary sequences of drill hole QC4 and some sections,and the characteristics of the coastal ridges in North Jiangsu Province.These coastal ridges are mostly composed of non-biogenic fine and middle sands.It is much different from composition of the shell ridges being mainly composed of molluscan shells and their fragments on the west coast of the Bohai Sea,where is the abandoned Huanghe River Delta area.In 8 500~7 000 a BP,the west coastline of the Bohai Sea retreated for tens kilometers,the Huanghe River channel free shifted and the fine sediments carried into the Bohai Sea by the Huanghe River were resuspended,transported and reworked into the shallow marine deposits.The Huanghe River subaqueous delta could not be formed in this period.The Holocene Huanghe River Delta has been formed since 7 000 a BP, when the sea level rise decelerated and close to the stable level.
2004, 26(1): 62-75.
Abstract:
Common diversity indices such as species richness,Shannon index(base 2 or e),Pielou evenness index, Simpson index(1-D or 1/D form),Mar galef index,Berger Parker index,McIntosh index,McIntosh evenness index,Brillouin entropy index,Brillouin evenness index,Fisher and Qstatistic index,used for analyzing phytoplankton community were studied.We compared three phytoplankton species matrix to test these indices. They are species richness dependent ideal data set,cell abundance dependent ideal data set and real phy to plankton data set from the Bohai Sea and the Kuroshio water.The results show that each index has different functions on evaluating the diversity of a phytoplankton community.In general,integ rated using of species richness,Margalef index,Fisher index,Shannon index,Simpson index(1-D form)and Pielou index were fit for analyzing the phytoplankton community.But it should be cautious to use Margalef and Fisher index in analyzing the phytoplankton community.Ageneral guideline for the analysis of phytoplankton community diversity was established.
Common diversity indices such as species richness,Shannon index(base 2 or e),Pielou evenness index, Simpson index(1-D or 1/D form),Mar galef index,Berger Parker index,McIntosh index,McIntosh evenness index,Brillouin entropy index,Brillouin evenness index,Fisher and Qstatistic index,used for analyzing phytoplankton community were studied.We compared three phytoplankton species matrix to test these indices. They are species richness dependent ideal data set,cell abundance dependent ideal data set and real phy to plankton data set from the Bohai Sea and the Kuroshio water.The results show that each index has different functions on evaluating the diversity of a phytoplankton community.In general,integ rated using of species richness,Margalef index,Fisher index,Shannon index,Simpson index(1-D form)and Pielou index were fit for analyzing the phytoplankton community.But it should be cautious to use Margalef and Fisher index in analyzing the phytoplankton community.Ageneral guideline for the analysis of phytoplankton community diversity was established.
2004, 26(1): 76-81.
Abstract:
The toxicities of two typical HA Bspecies Alex andrium tamarense and Heterosigma akashiwo were studied by two standard experimental organisms:Neomysis awatschensis and Artemia salina as test organisms.The results show that both A.tamarense and H.akashiwo affected the survival of N.awatschensis during 96 h exposure.The 96 h LC50 of A.tamarense and H.akashiwo on N.awatschensis are about 7 000 cells/cm3 and 450 000 cells/cm3,respectively.While A.tamarense and H.akashiwo do not show any impact on the survival of Artemia salina during 24 h exposure.However,H.akashiwo can inhibit the activity of the Artemia salina significantly.The 96 h EC50 at 0,1,1.5,5 and 24 h are 15 000,7 500,4 500,3 000 cells/cm3,respectively. But at the low densities of 3 000 cells/cm3,the activity of the Artemia salina can recover to the normal degree after 48 h.The results indicate the two HAB species have different toxicities to the same or ganism and the two crustaceans can have different responses to the same species.
The toxicities of two typical HA Bspecies Alex andrium tamarense and Heterosigma akashiwo were studied by two standard experimental organisms:Neomysis awatschensis and Artemia salina as test organisms.The results show that both A.tamarense and H.akashiwo affected the survival of N.awatschensis during 96 h exposure.The 96 h LC50 of A.tamarense and H.akashiwo on N.awatschensis are about 7 000 cells/cm3 and 450 000 cells/cm3,respectively.While A.tamarense and H.akashiwo do not show any impact on the survival of Artemia salina during 24 h exposure.However,H.akashiwo can inhibit the activity of the Artemia salina significantly.The 96 h EC50 at 0,1,1.5,5 and 24 h are 15 000,7 500,4 500,3 000 cells/cm3,respectively. But at the low densities of 3 000 cells/cm3,the activity of the Artemia salina can recover to the normal degree after 48 h.The results indicate the two HAB species have different toxicities to the same or ganism and the two crustaceans can have different responses to the same species.
2004, 26(1): 82-87.
Abstract:
The histological structure and ultrastructure of the gill of the disk abalone Haliotis discus hannai Ino was observed with light microscope,scanning electron microscope and transmission electron microscope.Acording to the structure and function,the epithelium of each gill filament was seperated into five zones:frontal ciliated columnar epithelium,cuboidal epithelium,lateral ciliated columnar epithelium,respiratory epithelium and abfrontal ciliated columnar epithelium.Lateral cilia generate water current which goes among the gill filaments from ventral side. There are a number of small or large folds in the respiratory epithelium.The respiratory epithelial cells are only 6~ 8 m in height and have dense microvilli.Their structure fits for gas exchange.
The histological structure and ultrastructure of the gill of the disk abalone Haliotis discus hannai Ino was observed with light microscope,scanning electron microscope and transmission electron microscope.Acording to the structure and function,the epithelium of each gill filament was seperated into five zones:frontal ciliated columnar epithelium,cuboidal epithelium,lateral ciliated columnar epithelium,respiratory epithelium and abfrontal ciliated columnar epithelium.Lateral cilia generate water current which goes among the gill filaments from ventral side. There are a number of small or large folds in the respiratory epithelium.The respiratory epithelial cells are only 6~ 8 m in height and have dense microvilli.Their structure fits for gas exchange.
2004, 26(1): 88-94.
Abstract:
The karyotypes of three species of marine Veneroida molluscs,Solen grandis Dunker,Saxidomus purpuratus Sowerby and Mactra chinensis Philippi were studied by using the adult gill tissues.The chromosomes were prepared through injection of phytohemagglutinin(PHA)and colchicine,hypotonic treatment,chopping air-dry,and squashing technology.The results show that the diploid chromosome numbers of the three Veneroida species are the same as 2n=38.The karyotype of Solen grandis is 26 m+6 sm+2 st+4 t,NF=70,of Saxidomus purpuratus is 32 m+2 sm+4 st/t,NF=72,of Mactra chinensis is 20 m+16 sm+2 st/t,NF=74. Satellite and sex chromosome were not found among the chromosomes of three species.
The karyotypes of three species of marine Veneroida molluscs,Solen grandis Dunker,Saxidomus purpuratus Sowerby and Mactra chinensis Philippi were studied by using the adult gill tissues.The chromosomes were prepared through injection of phytohemagglutinin(PHA)and colchicine,hypotonic treatment,chopping air-dry,and squashing technology.The results show that the diploid chromosome numbers of the three Veneroida species are the same as 2n=38.The karyotype of Solen grandis is 26 m+6 sm+2 st+4 t,NF=70,of Saxidomus purpuratus is 32 m+2 sm+4 st/t,NF=72,of Mactra chinensis is 20 m+16 sm+2 st/t,NF=74. Satellite and sex chromosome were not found among the chromosomes of three species.
2004, 26(1): 95-104.
Abstract:
The validity of the genetic algorithm in estimating the directional spreading,reflection coefficient and reflective line distance is studied by numerical simulation.The genetic algorithm is verified by the numerical simulation of wave cross-spectrum and surface elevations.The directional spreading of the incident wave,reflection coefficient and reflection line distance are obtained by optimizing a fitness parameter which is a function of the difference between the simulated and theoretical cross-spectra.The numerical simulation results show that the genetic algorithm can accurately separate the incident and reflected wave in multi-directional reflective wave fields without a prior knowledge of the reflection line position.The analytic and model test results indicate that the genetic algorithm can be applied to analyzing the multi-directional random wave reflection.
The validity of the genetic algorithm in estimating the directional spreading,reflection coefficient and reflective line distance is studied by numerical simulation.The genetic algorithm is verified by the numerical simulation of wave cross-spectrum and surface elevations.The directional spreading of the incident wave,reflection coefficient and reflection line distance are obtained by optimizing a fitness parameter which is a function of the difference between the simulated and theoretical cross-spectra.The numerical simulation results show that the genetic algorithm can accurately separate the incident and reflected wave in multi-directional reflective wave fields without a prior knowledge of the reflection line position.The analytic and model test results indicate that the genetic algorithm can be applied to analyzing the multi-directional random wave reflection.
2004, 26(1): 105-112.
Abstract:
The experiments of pollutant transport in coastal zone were carried out on the two gently sloping beach of 1:100 and 1:40 slope for diverse wave cases.The movement range and direction of pollutants in the diverse zones of the gently sloping beach under the action of regular and irregular waves were provided and studied.
The experiments of pollutant transport in coastal zone were carried out on the two gently sloping beach of 1:100 and 1:40 slope for diverse wave cases.The movement range and direction of pollutants in the diverse zones of the gently sloping beach under the action of regular and irregular waves were provided and studied.
2004, 26(1): 113-124.
Abstract:
A new analytical method is proposed to analyze the force acting on a recangular oscillating buoy due to linear waves.In the method a new analytical expression for the diffraction velocity potential is obtained first by use of an eigenfunction expansion method and then the wave excitation force is calculated by use of the known incident wave potential and the diffraction potential.Compared with the classical analytical method,it can be seen that the present method is simpler for a two-dimensional problem due to the comparable effort needed for the computation of diffraction potential and for that of radiation potential.To verify the correctness of the method,a classical example in the reference is recomputed and the obtained results are in good accordance with those by use of other methods, which shows that the present method is correct.
A new analytical method is proposed to analyze the force acting on a recangular oscillating buoy due to linear waves.In the method a new analytical expression for the diffraction velocity potential is obtained first by use of an eigenfunction expansion method and then the wave excitation force is calculated by use of the known incident wave potential and the diffraction potential.Compared with the classical analytical method,it can be seen that the present method is simpler for a two-dimensional problem due to the comparable effort needed for the computation of diffraction potential and for that of radiation potential.To verify the correctness of the method,a classical example in the reference is recomputed and the obtained results are in good accordance with those by use of other methods, which shows that the present method is correct.
2004, 26(1): 125-131.
Abstract:
Based on lots of observation data,the interaction of fluctuating river flow with a barotropic tide was analyzed by wavelet transform.It can be concluded that the periodic variation of tidal range and water level has both typical semidiurnal and diurnal and semi monthly period of tide,and 64.8 d period of river runoff,which indicates that water level of the Zhujiang Delta is controlled by tide and river flow.The inverse correlation between tidal amplitude of different river ways and river discharges is significant and the more river discharge the less tidal amplitude and tidal range;the tidal range of Sanshui Station decreases with river discharge about at 0.000 2 velocity but more slow in lower reaches of the Zhujiang River Delta.It is indicated that the tidal effect intensity and the tidal range decrease rapidly along river way because the consumed tidal energy for overcoming the resistance of river discharge increases with increasing river discharge in upper reaches;the partial tide such as D1,D2 and D4 of Sanshui Station decreases significantly with increasing river discharge,but the amplitude of D2 reduces more quickly.
Based on lots of observation data,the interaction of fluctuating river flow with a barotropic tide was analyzed by wavelet transform.It can be concluded that the periodic variation of tidal range and water level has both typical semidiurnal and diurnal and semi monthly period of tide,and 64.8 d period of river runoff,which indicates that water level of the Zhujiang Delta is controlled by tide and river flow.The inverse correlation between tidal amplitude of different river ways and river discharges is significant and the more river discharge the less tidal amplitude and tidal range;the tidal range of Sanshui Station decreases with river discharge about at 0.000 2 velocity but more slow in lower reaches of the Zhujiang River Delta.It is indicated that the tidal effect intensity and the tidal range decrease rapidly along river way because the consumed tidal energy for overcoming the resistance of river discharge increases with increasing river discharge in upper reaches;the partial tide such as D1,D2 and D4 of Sanshui Station decreases significantly with increasing river discharge,but the amplitude of D2 reduces more quickly.
2004, 26(1): 132-136.
Abstract:
2004, 26(1): 137-145.
Abstract:
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