2002 Vol. 24, No. 3
Display Method:
2002, 24(3): 1-8.
Abstract:
Historical CTD data of the full-depth measurements which were conducted during the 15th Antarctic Survey of China in the period from November 1998 to February 1999 are used to analyze and discuss the marine physical characteristics of the Circumpolar Deep Water (CDW) and the Antarctic Bottom Water (AABW),and their spacial distribution in the Southern Ocean to the north of the Prydz Bay.The results are compared with the discovery by other oceano graphers in the historical liter ature.It is pointed out that CDW extends southward in the depths from 100×104 Pa to 2 000×104 Pa in the studied area.Both the high temperature core (t>1.2℃) and the high salinity core (S>34.7) of CDW become the thickest and extend the furthest southward in the 75°E section among all the 3 sections.AABW extends northward from the continental shelf in the depthsbelow 2 500×104 Pa.The high-density water (σθ>27.875) becomes the thickest and extends the furthest northward in the 70°E section.In addition,the CTD data from the measurements are used to provide the scientific evidence for the longitudinal circulation pattern in CDW and AABW,which is coincident with the features of deacan cell,sub-polar cell and deep cell in the Southern Ocean.
Historical CTD data of the full-depth measurements which were conducted during the 15th Antarctic Survey of China in the period from November 1998 to February 1999 are used to analyze and discuss the marine physical characteristics of the Circumpolar Deep Water (CDW) and the Antarctic Bottom Water (AABW),and their spacial distribution in the Southern Ocean to the north of the Prydz Bay.The results are compared with the discovery by other oceano graphers in the historical liter ature.It is pointed out that CDW extends southward in the depths from 100×104 Pa to 2 000×104 Pa in the studied area.Both the high temperature core (t>1.2℃) and the high salinity core (S>34.7) of CDW become the thickest and extend the furthest southward in the 75°E section among all the 3 sections.AABW extends northward from the continental shelf in the depthsbelow 2 500×104 Pa.The high-density water (σθ>27.875) becomes the thickest and extends the furthest northward in the 70°E section.In addition,the CTD data from the measurements are used to provide the scientific evidence for the longitudinal circulation pattern in CDW and AABW,which is coincident with the features of deacan cell,sub-polar cell and deep cell in the Southern Ocean.
2002, 24(3): 9-17.
Abstract:
Flows in firths exhibit obvious 3-D structure due to the complex topography and runoffs.Three-D modeling should be performed in order to reproduce various processes existing in firths.In practice,it is quite suitable to choosing the POM model,which uses or thogonal curvilinear coordinates in the horizontal and σ coordinate in the vertical as the hydrodynamic part of the modeling system.Combined with a 3-D Lagrangian drifter tracking module and a water quality module,the POM model is utilized to study water exchange and pollutant transport in the Yulin Firth.
Flows in firths exhibit obvious 3-D structure due to the complex topography and runoffs.Three-D modeling should be performed in order to reproduce various processes existing in firths.In practice,it is quite suitable to choosing the POM model,which uses or thogonal curvilinear coordinates in the horizontal and σ coordinate in the vertical as the hydrodynamic part of the modeling system.Combined with a 3-D Lagrangian drifter tracking module and a water quality module,the POM model is utilized to study water exchange and pollutant transport in the Yulin Firth.
2002, 24(3): 18-27.
Abstract:
Marine,an indispensable part of our country,is the important platform for the exploitation of a variety of marine resources.It has long been the common case that marine has been taken advantage of free of charge,giving rise to a disorderly exploitation,an aggravated pollution and even the great loss of marine creatures.Therefore,the damaged ecological environment and lost ecological equilibrium prevent the sustainable development of coastal areas.Combining with "the differential land rent" in economics and "the AHP (analytic hierarchy process)" in operational research with the real conditions (such as the social,economic factors and basic facilities and natural resources) of 11 coastal provinces,cities and autonomous region,to make a theoretical research and grade the marine under our jurisdiction is attempted,thus making a solid foundation for the establishment of the tolling standard for the reimbursable utilization of the marine resources.
Marine,an indispensable part of our country,is the important platform for the exploitation of a variety of marine resources.It has long been the common case that marine has been taken advantage of free of charge,giving rise to a disorderly exploitation,an aggravated pollution and even the great loss of marine creatures.Therefore,the damaged ecological environment and lost ecological equilibrium prevent the sustainable development of coastal areas.Combining with "the differential land rent" in economics and "the AHP (analytic hierarchy process)" in operational research with the real conditions (such as the social,economic factors and basic facilities and natural resources) of 11 coastal provinces,cities and autonomous region,to make a theoretical research and grade the marine under our jurisdiction is attempted,thus making a solid foundation for the establishment of the tolling standard for the reimbursable utilization of the marine resources.
The general status of storm surges and the simulation of extratropical storm surges in the Bohai Sea
2002, 24(3): 28-34.
Abstract:
The analyses and investigations indicate that the frequency of storm surge of Tianjin coastal area is the highest and its disaster is the most severe in the world.The disaster of storm surge happens in fourseasons in which the disaster of extratropical storm surge occurs in spring,autumn and winter except the disaster of typhoon surge happens in summer.The 2-D model in geographical coordinates has been used to simulate the highest case of extratropical storm surge in the Bohai Seawhich happened in 23 April 1969.The verification of calculated wind field and the time variation of storm surge in several tidal gauge stations indicates that the model can be used to do the engineering calculations of the extratropical storm surge,and the model has an ability to do the real-time prediction of storm surges.
The analyses and investigations indicate that the frequency of storm surge of Tianjin coastal area is the highest and its disaster is the most severe in the world.The disaster of storm surge happens in fourseasons in which the disaster of extratropical storm surge occurs in spring,autumn and winter except the disaster of typhoon surge happens in summer.The 2-D model in geographical coordinates has been used to simulate the highest case of extratropical storm surge in the Bohai Seawhich happened in 23 April 1969.The verification of calculated wind field and the time variation of storm surge in several tidal gauge stations indicates that the model can be used to do the engineering calculations of the extratropical storm surge,and the model has an ability to do the real-time prediction of storm surges.
2002, 24(3): 35-44.
Abstract:
The relationship between the characteristics of the upper ocean change in the West Pacific warm pool region (0°~16°N,125°~145°E) and the subsurface ocean temperature field in the West Pacific is analyzed by XBT temperature data in the upper tropical Pacific.The research results show that the annual change of the vertical distribution of the ocean temperature in the West Pacific warm pool region is notable and particularly that in subsurface layers (120~200 m) is most obvious.The anomalous change of the ocean temperature signals in the warm pool earlier than that of the subsurface in the West Pacific,and the former is leading to the key region of the subsurface ocean temperature variation in the West Pacific.The subsurface ocean temperature in the West Pacific anomalous change will appear after 3~4 months when the anomaly signals of the subsurface ocean temperature enhance in the warm pool region.
The relationship between the characteristics of the upper ocean change in the West Pacific warm pool region (0°~16°N,125°~145°E) and the subsurface ocean temperature field in the West Pacific is analyzed by XBT temperature data in the upper tropical Pacific.The research results show that the annual change of the vertical distribution of the ocean temperature in the West Pacific warm pool region is notable and particularly that in subsurface layers (120~200 m) is most obvious.The anomalous change of the ocean temperature signals in the warm pool earlier than that of the subsurface in the West Pacific,and the former is leading to the key region of the subsurface ocean temperature variation in the West Pacific.The subsurface ocean temperature in the West Pacific anomalous change will appear after 3~4 months when the anomaly signals of the subsurface ocean temperature enhance in the warm pool region.
2002, 24(3): 45-51.
Abstract:
With the aid of previous research on ocean wave spectrum and the magnetic field induced by ocean waves,the power transfer function of ocean wave-magnetic field system is determined.The peak value of the transfer function and the corresponding frequency are determined and the changes of these two quantities as a function of height are analyzed.According to the theoretical analysis,the analytical expression of the total magnetic power is determined and the equation that the peak-power frequency satisfies is provided.It is pointed out that the induced magnetic field is a narrow-band process.Finally,the power spectral density,total power,the maximum of the PSD,maximum frequency and equivalent frequency of induced magnetic field are calculated for some typical wave spectra.
With the aid of previous research on ocean wave spectrum and the magnetic field induced by ocean waves,the power transfer function of ocean wave-magnetic field system is determined.The peak value of the transfer function and the corresponding frequency are determined and the changes of these two quantities as a function of height are analyzed.According to the theoretical analysis,the analytical expression of the total magnetic power is determined and the equation that the peak-power frequency satisfies is provided.It is pointed out that the induced magnetic field is a narrow-band process.Finally,the power spectral density,total power,the maximum of the PSD,maximum frequency and equivalent frequency of induced magnetic field are calculated for some typical wave spectra.
2002, 24(3): 52-59.
Abstract:
The profile of nutrient salts in interstitial water of sediment are analyzed in the Zhujiang Estuary (Pearl River Estuary) in the summer of 1999,and based on the profiles of content and characteristic of nutrients,the relationship between nutrients in interstitial water and organic matter decomposition in sediment is discussed.The results show that ammonium with high content is the main existence form of nutrients in interstitial water of sediment,and organic matter decomposition is completed in anaerobic condition.The increase of ammonium content in bottom water results from the decomposition of organic matter and release of metabolic production,and bottom ammonium flux is an important resource for nutrients geochemistry in the Zhujiang Estuary.
The profile of nutrient salts in interstitial water of sediment are analyzed in the Zhujiang Estuary (Pearl River Estuary) in the summer of 1999,and based on the profiles of content and characteristic of nutrients,the relationship between nutrients in interstitial water and organic matter decomposition in sediment is discussed.The results show that ammonium with high content is the main existence form of nutrients in interstitial water of sediment,and organic matter decomposition is completed in anaerobic condition.The increase of ammonium content in bottom water results from the decomposition of organic matter and release of metabolic production,and bottom ammonium flux is an important resource for nutrients geochemistry in the Zhujiang Estuary.
2002, 24(3): 60-67.
Abstract:
Quantitative study on the Xuejiadao coast evolution based on 4 a continuous field survey shows that most margin of the Xuejiadao area is the bedrock headland-bay erosive coast whose anti-eroding strength is great.The average velocity of the back-eroding and down-eroding is at the level of 10-2 and 10-4 m/a,respectively.There is modern beach grit lamella on the tip of the bow bay,and a great deal of big gravels of beach-faces in front of the cliff and on the backshore of Shique Bay and Silver Beach (the granularity of them can reach 20~30 cm).Outside coast is facing to the open sea,and the underwater bank slope is steep and deep,the intensity of exogenetic force factors such as meteorology and hydrology is relatively great.All these features display the geological and geomorphological characteristics of middle-high energy coast.The source of alimentation of the coastal wash in the open sea off Xuejiadao is poor,which is less than 2×104 m3/a.The direction of littoral wash flow is from northeast to southwest,and the capability can reach 13×104 m3/a.The unbalancedness between sediment source and carrying capacity is the mechanism of the formation of the bedrock erosive coast.
Quantitative study on the Xuejiadao coast evolution based on 4 a continuous field survey shows that most margin of the Xuejiadao area is the bedrock headland-bay erosive coast whose anti-eroding strength is great.The average velocity of the back-eroding and down-eroding is at the level of 10-2 and 10-4 m/a,respectively.There is modern beach grit lamella on the tip of the bow bay,and a great deal of big gravels of beach-faces in front of the cliff and on the backshore of Shique Bay and Silver Beach (the granularity of them can reach 20~30 cm).Outside coast is facing to the open sea,and the underwater bank slope is steep and deep,the intensity of exogenetic force factors such as meteorology and hydrology is relatively great.All these features display the geological and geomorphological characteristics of middle-high energy coast.The source of alimentation of the coastal wash in the open sea off Xuejiadao is poor,which is less than 2×104 m3/a.The direction of littoral wash flow is from northeast to southwest,and the capability can reach 13×104 m3/a.The unbalancedness between sediment source and carrying capacity is the mechanism of the formation of the bedrock erosive coast.
2002, 24(3): 68-74.
Abstract:
The data about geology,geomorphology and geophysics are analyzed and summarized in the Lower Liaohe River Plain and the Liaodong Gulf.The main features of neotectonic movements and their expressions in the characteristics of paleogene,neogene and Quaternary stata as well as landforms are pointed out.
The data about geology,geomorphology and geophysics are analyzed and summarized in the Lower Liaohe River Plain and the Liaodong Gulf.The main features of neotectonic movements and their expressions in the characteristics of paleogene,neogene and Quaternary stata as well as landforms are pointed out.
2002, 24(3): 75-80.
Abstract:
Test tools and method of synchronizing acoustic measure at the stress-strain course for sea floor sediments are expatiated on,and the test data of 45 sediment samples which sampled from sea floor in South China Sea are analysed.The result shows that the more sediment grain course,the more porosity small,and the bigger unconfined compression strength,the more sound velocity high.In the stress-strain course,the sediment sound velocity has obvious variance as the stress changes.Acoustic characteristics of sediments in strain phases and the course of influence of sediment microstructure variance on its sound velocity are discussed.This study will have important significance for surveying well of petroleum geology and evaluating base stabilization of sea floor engineering.
Test tools and method of synchronizing acoustic measure at the stress-strain course for sea floor sediments are expatiated on,and the test data of 45 sediment samples which sampled from sea floor in South China Sea are analysed.The result shows that the more sediment grain course,the more porosity small,and the bigger unconfined compression strength,the more sound velocity high.In the stress-strain course,the sediment sound velocity has obvious variance as the stress changes.Acoustic characteristics of sediments in strain phases and the course of influence of sediment microstructure variance on its sound velocity are discussed.This study will have important significance for surveying well of petroleum geology and evaluating base stabilization of sea floor engineering.
2002, 24(3): 81-87.
Abstract:
Based on the analysis of oxygen and cqrbon data,it is found that there are clear stage changes at oxygen and carbon isotopic composition of foraminiferal crusts in HY126EA1 hole.Compared with oxygen isotopic composition of deep sea,the change of oxygen isotopic composition can be divided into five periods,which correspond to the deglaciation,the last glacial maximum,the interglacial stage of last glacial age,late last glacial age,and the last interglacial period,respectively.the change of carbon isotopic composition is almost the same as that of oxygen's.According to the correlation analysis of δ18O and δ13C,obvious difference in different oxygen isotopic periods can be seen,which indicates the diference of exchange of water body at different periods.
Based on the analysis of oxygen and cqrbon data,it is found that there are clear stage changes at oxygen and carbon isotopic composition of foraminiferal crusts in HY126EA1 hole.Compared with oxygen isotopic composition of deep sea,the change of oxygen isotopic composition can be divided into five periods,which correspond to the deglaciation,the last glacial maximum,the interglacial stage of last glacial age,late last glacial age,and the last interglacial period,respectively.the change of carbon isotopic composition is almost the same as that of oxygen's.According to the correlation analysis of δ18O and δ13C,obvious difference in different oxygen isotopic periods can be seen,which indicates the diference of exchange of water body at different periods.
2002, 24(3): 88-93.
Abstract:
The analysis of nutrient compositions for Bostrychia mixta,Catenella impudica,Caloglossa leprieurii and Enteromorpha compressa that grow in Fujian mangrove areas shows that concentration of Feor Mnin these four algae is much higher than the mean concentration of Fe or Mn in common algae;concentration of Ca is lower than mean concentration of Ca in common algae;concentration of P,K,Mg is higher or lower than mean concentration of P,K,Mg in common algae.The range of concentration of total amino acids (TAA) among 4 algae is Enteromorpha compressa(DW) 265.89 mg/g > Bostrychia mixta 211.96 mg/g > Caloglossalep rieurii 189.53 mg/g > Catenella impudica 111.10 mg/g;the range of concentration of essential amino acids(EAA) is Bostrychia mixta 87.42mg/g > Enteromorpha compressa 82.92 mg/g > Caloglossa leprieurii 73.62 mg/g > Catenella impudica 34.41 mg/g.The TAA or EAA concentration in Caloglossa leprieurii growing on the buttress-like root surface of K andelia candel is higher than that on rocky surface near the Kandelia candel forest in March and June,respectively.Concentrations of chemical elements in Caloglossa leprieurii growing in the different habitats change with March and June.
The analysis of nutrient compositions for Bostrychia mixta,Catenella impudica,Caloglossa leprieurii and Enteromorpha compressa that grow in Fujian mangrove areas shows that concentration of Feor Mnin these four algae is much higher than the mean concentration of Fe or Mn in common algae;concentration of Ca is lower than mean concentration of Ca in common algae;concentration of P,K,Mg is higher or lower than mean concentration of P,K,Mg in common algae.The range of concentration of total amino acids (TAA) among 4 algae is Enteromorpha compressa(DW) 265.89 mg/g > Bostrychia mixta 211.96 mg/g > Caloglossalep rieurii 189.53 mg/g > Catenella impudica 111.10 mg/g;the range of concentration of essential amino acids(EAA) is Bostrychia mixta 87.42mg/g > Enteromorpha compressa 82.92 mg/g > Caloglossa leprieurii 73.62 mg/g > Catenella impudica 34.41 mg/g.The TAA or EAA concentration in Caloglossa leprieurii growing on the buttress-like root surface of K andelia candel is higher than that on rocky surface near the Kandelia candel forest in March and June,respectively.Concentrations of chemical elements in Caloglossa leprieurii growing in the different habitats change with March and June.
2002, 24(3): 94-100.
Abstract:
A three-factors and four-levels orthogonal experiment,including ultrasonic frequency,power and treatment duration,is conducted to study biological effect of ultrasonic treatment on Isochrysis zhanjiangensis.The experimental results suggest that ultrasonic frequency has significant biological effect,and ultrasonic power and treatment duration have less influence on this alga.The optimum ultrasonic conditions are 20 kHz,6 W,10 s (triplicate) for increasing the constant of growth rate of this alga,and 20 kHz,4~6 W,30 s for increasing its unsaturation degree of total fatty acids(TFA) and the percentages of major unsaturated fatty acids.The maximum constant of growth rate of Isochrysis zhanjiangensis can be 0.630 d which is 2.02 times of that of the controls.The maximum unsaturation degree can be 79.6% which was 7.8% higher than that of the controls.The percentages of major unsaturated fatty acids in TFA can increase more or less under the optimum ultrasonic conditions.
A three-factors and four-levels orthogonal experiment,including ultrasonic frequency,power and treatment duration,is conducted to study biological effect of ultrasonic treatment on Isochrysis zhanjiangensis.The experimental results suggest that ultrasonic frequency has significant biological effect,and ultrasonic power and treatment duration have less influence on this alga.The optimum ultrasonic conditions are 20 kHz,6 W,10 s (triplicate) for increasing the constant of growth rate of this alga,and 20 kHz,4~6 W,30 s for increasing its unsaturation degree of total fatty acids(TFA) and the percentages of major unsaturated fatty acids.The maximum constant of growth rate of Isochrysis zhanjiangensis can be 0.630 d which is 2.02 times of that of the controls.The maximum unsaturation degree can be 79.6% which was 7.8% higher than that of the controls.The percentages of major unsaturated fatty acids in TFA can increase more or less under the optimum ultrasonic conditions.
2002, 24(3): 101-111.
Abstract:
The distribution of chlorophyll a concentration (Chl a),primary production (PP) and new production (NP) were observed in the estuary of Zhujiang River (the Pearl River) during December.1996 and August.1997.The results show that the average concentration of Chl a,PP and NP in winter and summer are (0.95×0.41) and (1.08×0.52) μg/dm3,(69.2×75.5) and (198.7×119.1) mg/(m2·d),and (1.46×0.79) and (3.05×3.09) mg/(m3·h),respectively.The values are higher in summer than in winter.The average-fratio are 0.45 and 0.38 in winter and summer,respectively.The results of size-fractionated Chl a and PP show that the contribution of nano-and pico-plankton (<20 μm) to total Chl a and PP are in dominant position in phytoplankton community biomass and production.The average contributions to total Chl a are 79.6% and 81.6% in winter and summer,respectively,and to primary production are 70.7% and 89.6%,respectively.There are marked features of spatial zonation characteristics of Chl a and PP in the surveyed area.The highest value of Chl a and potential PP appears in the middle area of the dilution zone and decreases both mouth ward and offshoreward gradually.The high PP appears in the offshore areas.The euphotic production has a good relationship with the composite variable BeZpI0 (Be is average euphotic zone Chl a;Zp euphotic depth;I0 surface irradiance-PAR),which suggests that light is main limiting factor to the production.The highest value of new production appears in the Jiaoyi Bay during winter and in southwest part of the Lingding Yang during summer.
The distribution of chlorophyll a concentration (Chl a),primary production (PP) and new production (NP) were observed in the estuary of Zhujiang River (the Pearl River) during December.1996 and August.1997.The results show that the average concentration of Chl a,PP and NP in winter and summer are (0.95×0.41) and (1.08×0.52) μg/dm3,(69.2×75.5) and (198.7×119.1) mg/(m2·d),and (1.46×0.79) and (3.05×3.09) mg/(m3·h),respectively.The values are higher in summer than in winter.The average-fratio are 0.45 and 0.38 in winter and summer,respectively.The results of size-fractionated Chl a and PP show that the contribution of nano-and pico-plankton (<20 μm) to total Chl a and PP are in dominant position in phytoplankton community biomass and production.The average contributions to total Chl a are 79.6% and 81.6% in winter and summer,respectively,and to primary production are 70.7% and 89.6%,respectively.There are marked features of spatial zonation characteristics of Chl a and PP in the surveyed area.The highest value of Chl a and potential PP appears in the middle area of the dilution zone and decreases both mouth ward and offshoreward gradually.The high PP appears in the offshore areas.The euphotic production has a good relationship with the composite variable BeZpI0 (Be is average euphotic zone Chl a;Zp euphotic depth;I0 surface irradiance-PAR),which suggests that light is main limiting factor to the production.The highest value of new production appears in the Jiaoyi Bay during winter and in southwest part of the Lingding Yang during summer.
2002, 24(3): 112-118.
Abstract:
Seasonal changes in the caloric values and ash contents of the leaves of seven mangrove species at Futian,Shenzhen are discussed,the result shows as follows:(1) there were differences in ash contents of the leaves of seven mangrove species;(2) gross caloric values(y) correlate remarkably with ash contents(x) for Excoecaria agallocha leaves and Heritiera littoralis leaves,respectively.There is no significant relation between gross caloric values and ash contents for other mangrove species;(3) for seasonal changes in the gross caloric values,there is extremely significant relation between gross caloric values and ash contents in January and April 2001,significant relation in July 2000,no significant relation in October 2000,respectively;(4) seasonal changes in ash free caloric values are different form those in gross caloric values,but seasonal ash free caloric values in the leaves of seven mangrove species are all the highest in autumn.
Seasonal changes in the caloric values and ash contents of the leaves of seven mangrove species at Futian,Shenzhen are discussed,the result shows as follows:(1) there were differences in ash contents of the leaves of seven mangrove species;(2) gross caloric values(y) correlate remarkably with ash contents(x) for Excoecaria agallocha leaves and Heritiera littoralis leaves,respectively.There is no significant relation between gross caloric values and ash contents for other mangrove species;(3) for seasonal changes in the gross caloric values,there is extremely significant relation between gross caloric values and ash contents in January and April 2001,significant relation in July 2000,no significant relation in October 2000,respectively;(4) seasonal changes in ash free caloric values are different form those in gross caloric values,but seasonal ash free caloric values in the leaves of seven mangrove species are all the highest in autumn.
2002, 24(3): 119-127.
Abstract:
How to separate oblique irregular incident and reflected waves in front of vertical wall mode in laboratory basin is studied,and a kind of two-points method that can be used to separate the oblique incident wave in which the two gauges can be placed at any direction in front of vertical wall is proposed.To analyze the factors which can influence the separated results,the results with different conditions,such as the position of the two distinct gauges,the different sea bed height,the different incident wave height and peak frequency are tested.It shows that there are evidently different among those conditions,in partically,the influence of the position of two wave gauges is more dominant.
How to separate oblique irregular incident and reflected waves in front of vertical wall mode in laboratory basin is studied,and a kind of two-points method that can be used to separate the oblique incident wave in which the two gauges can be placed at any direction in front of vertical wall is proposed.To analyze the factors which can influence the separated results,the results with different conditions,such as the position of the two distinct gauges,the different sea bed height,the different incident wave height and peak frequency are tested.It shows that there are evidently different among those conditions,in partically,the influence of the position of two wave gauges is more dominant.
2002, 24(3): 128-135.
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2002, 24(3): 136-141.
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2002, 24(3): 142-147.
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