2005 Vol. 24, No. 5
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Display Method:
2005, (5): 1-13.
Abstract:
In the numerical studies of a real tide M4 resonance system, the Xiangshan Port which is a partially-closed bay, Dong et al.[1999.Acta Oceanologica Sinica, 21 (3):1~6] found the interesting phenomenon that the advection plays an important role in inhibiting the growth of the amplitude of the tidal second-order resonance response (M4).This result is contrary to the general traditional ideas for a non-resonance system.How this phenomenon is interpreted and what internal mechanism is behind the phenomenon are the main focuses of this study.The followings are examined:(1) the dynamic features of a second-order resonance system of tide; (2) the dominating factors on the second-order resonance responses; (3) the effects of both the friction and the advection on the second-order resonance responses; and (4) their roles in dominating the second-order resonance response and internal mechanisms by using the analytical methods.The respective results show that:(1) Both the bottom friction and the advection play significant roles in dominating the magnitude of the amplitude of the second-order resonance responses; (2) the effect of the friction on the second-order resonance response depends on the distribution ratio of the work-done of the system to friction force exhausted into between the damping of the first-order system and the inner excitation of the second-order system; (3) the advection plays a positive role in increasing the amplitude of the second-order non-resonance response in the second order non-resonance of tide; (4) in a second-order resonance system of tide, the effect of the advection may be either to increase or to decrease the amplitudes of the second-order resonance responses of tide, which depends on the distribution ratio mentioned above
In the numerical studies of a real tide M4 resonance system, the Xiangshan Port which is a partially-closed bay, Dong et al.[1999.Acta Oceanologica Sinica, 21 (3):1~6] found the interesting phenomenon that the advection plays an important role in inhibiting the growth of the amplitude of the tidal second-order resonance response (M4).This result is contrary to the general traditional ideas for a non-resonance system.How this phenomenon is interpreted and what internal mechanism is behind the phenomenon are the main focuses of this study.The followings are examined:(1) the dynamic features of a second-order resonance system of tide; (2) the dominating factors on the second-order resonance responses; (3) the effects of both the friction and the advection on the second-order resonance responses; and (4) their roles in dominating the second-order resonance response and internal mechanisms by using the analytical methods.The respective results show that:(1) Both the bottom friction and the advection play significant roles in dominating the magnitude of the amplitude of the second-order resonance responses; (2) the effect of the friction on the second-order resonance response depends on the distribution ratio of the work-done of the system to friction force exhausted into between the damping of the first-order system and the inner excitation of the second-order system; (3) the advection plays a positive role in increasing the amplitude of the second-order non-resonance response in the second order non-resonance of tide; (4) in a second-order resonance system of tide, the effect of the advection may be either to increase or to decrease the amplitudes of the second-order resonance responses of tide, which depends on the distribution ratio mentioned above
2005, (5): 14-26.
Abstract:
The biases and their sources in monthly turbulent heat fluxes from the Woods Hole Oceanographic Institution (WHOI) analysis, and the National Centers for Environmental Prediction-National Center for Atmospheric Research reanalyses 1 and 2 (NCEP1 and NCEP2) are checked in the climatically representative regions in the tropical Atlantic using the fluxes from the Southampton Oceanographic Centre (SOC) and the pilot research moored array in the tropical Atlantic (PIRATA) as references.For the WHOI analysis, the biases in turbulent heat fluxes mainly exist in equatorial regions which are due to the overestimated sea surface temperature and the underestimated 2 m air humidity.For the NCEP2 reanalysis, the maximum biases, about (40±5)W/m2, exist in southeast and northeast trade wind regions, which are mainly caused by the flux algorithm used because the biases in wind speed and air-sea humidity difference are relatively small.In the equatorial regions, the flux biases in the NCEP2 derived from both flux-related basic variables and algorithm are equally large.Although the estimations of time series trends and air-sea humidity difference of the NCEP1 are improved greatly in the NCEP2, the biases of latent heat flux in the NCEP2 are about 20 W/m2 greater than those from the NCEP1 in the trade wind regions.The result shows that the climatologies and monthly variabilities of the turbulent heat fluxes from the WHOI are more accurate than those from the NCEP1 and NCEP2 in the tropical Atlantic, especially on outside of the equatorial regions.
The biases and their sources in monthly turbulent heat fluxes from the Woods Hole Oceanographic Institution (WHOI) analysis, and the National Centers for Environmental Prediction-National Center for Atmospheric Research reanalyses 1 and 2 (NCEP1 and NCEP2) are checked in the climatically representative regions in the tropical Atlantic using the fluxes from the Southampton Oceanographic Centre (SOC) and the pilot research moored array in the tropical Atlantic (PIRATA) as references.For the WHOI analysis, the biases in turbulent heat fluxes mainly exist in equatorial regions which are due to the overestimated sea surface temperature and the underestimated 2 m air humidity.For the NCEP2 reanalysis, the maximum biases, about (40±5)W/m2, exist in southeast and northeast trade wind regions, which are mainly caused by the flux algorithm used because the biases in wind speed and air-sea humidity difference are relatively small.In the equatorial regions, the flux biases in the NCEP2 derived from both flux-related basic variables and algorithm are equally large.Although the estimations of time series trends and air-sea humidity difference of the NCEP1 are improved greatly in the NCEP2, the biases of latent heat flux in the NCEP2 are about 20 W/m2 greater than those from the NCEP1 in the trade wind regions.The result shows that the climatologies and monthly variabilities of the turbulent heat fluxes from the WHOI are more accurate than those from the NCEP1 and NCEP2 in the tropical Atlantic, especially on outside of the equatorial regions.
2005, (5): 27-34.
Abstract:
By extracting and comparing long-term trend components of coral gray value, sea surface temperature, cloudiness, and net heat flux for the period of 1946~1992, the relationships among them are addressed.There exists a prominent regime shift in the cloudiness associated with the corresponding variabilities of sea surface temperature and net heat flux occurred in the mid-1960s, which can be successfully recorded by coral gray value, a climatic proxy.Long-term cloudiness variations in the South China Sea are completely opposite to the equatorial western Pacific in the past five decades, whereas they share a similar trend to that over Asian monsoon prevailing waters.The fact that the coral gray value is highly correlated to cloudiness provides a unique perspective on utilizing this coral to study cloudiness variations in the pre-instrumental period.
By extracting and comparing long-term trend components of coral gray value, sea surface temperature, cloudiness, and net heat flux for the period of 1946~1992, the relationships among them are addressed.There exists a prominent regime shift in the cloudiness associated with the corresponding variabilities of sea surface temperature and net heat flux occurred in the mid-1960s, which can be successfully recorded by coral gray value, a climatic proxy.Long-term cloudiness variations in the South China Sea are completely opposite to the equatorial western Pacific in the past five decades, whereas they share a similar trend to that over Asian monsoon prevailing waters.The fact that the coral gray value is highly correlated to cloudiness provides a unique perspective on utilizing this coral to study cloudiness variations in the pre-instrumental period.
2005, (5): 35-38.
Abstract:
A class of El Niño atmospheric physics oscillation model is considered.The El Niño atmospheric physics oscillation is an abnormal phenomenon involved in the tropical Pacific ocean-atmosphere interactions.The conceptual oscillator model should consider the variations of both the eastern and westem Pacific anomaly patterns.An El Niño atmospheric physics model is proposed using a method for the variational iteration theory.Using the variational iteration method, the approximate expansions of the solution of corresponding problem are constructed.That is, firstly, introducing a set of functional and accounting their variationals, the Lagrange multiplicators are counted, and then the variational iteration is defined, finally, the approximate solution is obtained.From approximate expansions of the solution, the zonal sea surface temperature anomaly in the equatorial eastern Pacific and the thermocline depth anomaly of the seaair oscillation for El Niño atmospheric physics model can be analyzed.El Niño is a very complicated natural phenomenon.Hence basic models need to be reduced for the sea-air oscillator and are solved.The variational iteration is a simple and valid approximate method.
A class of El Niño atmospheric physics oscillation model is considered.The El Niño atmospheric physics oscillation is an abnormal phenomenon involved in the tropical Pacific ocean-atmosphere interactions.The conceptual oscillator model should consider the variations of both the eastern and westem Pacific anomaly patterns.An El Niño atmospheric physics model is proposed using a method for the variational iteration theory.Using the variational iteration method, the approximate expansions of the solution of corresponding problem are constructed.That is, firstly, introducing a set of functional and accounting their variationals, the Lagrange multiplicators are counted, and then the variational iteration is defined, finally, the approximate solution is obtained.From approximate expansions of the solution, the zonal sea surface temperature anomaly in the equatorial eastern Pacific and the thermocline depth anomaly of the seaair oscillation for El Niño atmospheric physics model can be analyzed.El Niño is a very complicated natural phenomenon.Hence basic models need to be reduced for the sea-air oscillator and are solved.The variational iteration is a simple and valid approximate method.
2005, (5): 39-45.
Abstract:
A two-dimensional nonoscillatory central difference scheme was extended to the shallow water equations.A high-resolution numerical method for solving the shallow water equations was presented.In order to prevent oscillation, the nonlinear limiter is employed to approximate the discrete slopes.The main advantage of the presented method is simplicity comparable with the upwind schemes.This method does not require Riemann solvers or some form of flux difference splitting methods.Furthermore, the discrete derivatives of flux can be approximated by the component-wise approach and thus the computation of Jacobian can be avoided.The method retains high resolution and high accuracy similar to the upwind results.It is applied to simulating several tests, including circular dam-break problem, shock focusing problem and partial dam-break problem.The results are in good agreement with the numerical results obtained by other methods.The simulated results also demonstrate that the presented method is stable and efficient.
A two-dimensional nonoscillatory central difference scheme was extended to the shallow water equations.A high-resolution numerical method for solving the shallow water equations was presented.In order to prevent oscillation, the nonlinear limiter is employed to approximate the discrete slopes.The main advantage of the presented method is simplicity comparable with the upwind schemes.This method does not require Riemann solvers or some form of flux difference splitting methods.Furthermore, the discrete derivatives of flux can be approximated by the component-wise approach and thus the computation of Jacobian can be avoided.The method retains high resolution and high accuracy similar to the upwind results.It is applied to simulating several tests, including circular dam-break problem, shock focusing problem and partial dam-break problem.The results are in good agreement with the numerical results obtained by other methods.The simulated results also demonstrate that the presented method is stable and efficient.
2005, (5): 46-49.
Abstract:
Oceanic pycnocline depth is usually inferred from in situ measurements.It is attempted to estimate the depth remotely.As solitary internal waves occur on oceanic pycnocline and propagate along it, it is possible to retrieve the depth indirectly in virtue of the solitary internal waves.A numerical model is presented for retrieving the pycnocline depth from synthetic aperture radar (SAR) images where the solitary internal waves are visible and when ocean waters are fully stratified.This numerical model is constructed by combining the solitary internal wave model and a two-layer ocean model.It is also assumed that the observed groups of solitary internal wave packets on the SAR imagery are generated by local semidiurnal tides.A case study in the East China Sea shows a good agreement with in situ CTD (conductivity-temperature-depth) data.
Oceanic pycnocline depth is usually inferred from in situ measurements.It is attempted to estimate the depth remotely.As solitary internal waves occur on oceanic pycnocline and propagate along it, it is possible to retrieve the depth indirectly in virtue of the solitary internal waves.A numerical model is presented for retrieving the pycnocline depth from synthetic aperture radar (SAR) images where the solitary internal waves are visible and when ocean waters are fully stratified.This numerical model is constructed by combining the solitary internal wave model and a two-layer ocean model.It is also assumed that the observed groups of solitary internal wave packets on the SAR imagery are generated by local semidiurnal tides.A case study in the East China Sea shows a good agreement with in situ CTD (conductivity-temperature-depth) data.
2005, (5): 50-60.
Abstract:
In terms of the 2-dimensional hydrodynamic simplified model of a semi-elliptical submerged body moving horizontally at high speed, by using the full-spectrum model of SAR(synthetic aperture radar) remote sensing and taking the effect of oceanic interior turbulence on surface gravity capillary waves into account, applying the k-ε model of turbulence with internal wave mixing, and adopting the Nasmyth spectrum of oceanic turbulence, the 2-dimensional simulation model of SAR remote sensing of this semi-elliptical submerged body is built up.Simulation by using this model at X band and C band is made in the northeastern South China Sea (21°00'N, 119°00'E).Satisfactory results of the delay time and delay distance of turbulent surface wake of this semi-elliptical submerged body, as well as the minimum submerged depth at which this submerged body which cannot be discovered by SAR, are obtained through simulation.
In terms of the 2-dimensional hydrodynamic simplified model of a semi-elliptical submerged body moving horizontally at high speed, by using the full-spectrum model of SAR(synthetic aperture radar) remote sensing and taking the effect of oceanic interior turbulence on surface gravity capillary waves into account, applying the k-ε model of turbulence with internal wave mixing, and adopting the Nasmyth spectrum of oceanic turbulence, the 2-dimensional simulation model of SAR remote sensing of this semi-elliptical submerged body is built up.Simulation by using this model at X band and C band is made in the northeastern South China Sea (21°00'N, 119°00'E).Satisfactory results of the delay time and delay distance of turbulent surface wake of this semi-elliptical submerged body, as well as the minimum submerged depth at which this submerged body which cannot be discovered by SAR, are obtained through simulation.
2005, (5): 61-67.
Abstract:
Organic matter and iron and maganese oxides have been considered as the major affecting factors for metals in anoxic or oxidized sediment.In recent research, clay and sulfide are found as major factors in oxic or oxidized sediments that might affect bioavailability of metals.To test this hypothesis, the influence of sulfide, measured as acid-volatile sulfide (AVS), and clay content on the bioavailability of zinc and cadmium in sediments was examined.Laboratory simulative experiment and field verification experiment were conducted, showing that the bioavailability of zinc and cadmium is strongly correlated to AVS and clay content in sediments.Taking into account both AVS and clay parameters in sediments together can better indicate the bioavailability of zinc and cadmium rather than considering one of them alone.
Organic matter and iron and maganese oxides have been considered as the major affecting factors for metals in anoxic or oxidized sediment.In recent research, clay and sulfide are found as major factors in oxic or oxidized sediments that might affect bioavailability of metals.To test this hypothesis, the influence of sulfide, measured as acid-volatile sulfide (AVS), and clay content on the bioavailability of zinc and cadmium in sediments was examined.Laboratory simulative experiment and field verification experiment were conducted, showing that the bioavailability of zinc and cadmium is strongly correlated to AVS and clay content in sediments.Taking into account both AVS and clay parameters in sediments together can better indicate the bioavailability of zinc and cadmium rather than considering one of them alone.
2005, (5): 68-77.
Abstract:
The results of field observation carried out in May 2003 were used to examine pH and total alkalinity behaviors in the Changjiang Estuary.It was showed that pH and total alkalinity took on clear spatial variations in values with the minima in the low salinity region.Like salinity, transect distributions of pH and total alkalinity (TA) in a downriver direction had a sharp gradient each.These gradients appeared in such a sequence that the TA gradient was earlier than salinity and pH gradients, and the salinity gradient was earlier than the pH gradient.These distribution characteristics seemed to be strongly influenced by the mixing process of freshwater and seawater, for both pH and total alkalinity had significant linear relationships with salinity and temperature.For pH, phytoplankton activities also had a significant impact upon its spatial distribution.During a period of 48 h, pH and total alkalinity changed within wide ranges for every layer of the two anchor stations, namely, Stas 13 and 20, which were located at the mixed water mass and seawater mass, respectively.For both Stas 13 and 20, pH and TA fluctuation of every layer could be very wide during a 4 h period.As a whole, the data of the two anchor stations showed that neither variations in salinity and temperature nor phytoplankton activities were the main factors strongly influencing the total alkalinity temporal variability on a small time scale.The data of Sta.20 implied that both salinity variation and phytoplankton activities had a significant influence on pH temporal variability, but the same conclusion could not be drawn from the data of Sta.13.
The results of field observation carried out in May 2003 were used to examine pH and total alkalinity behaviors in the Changjiang Estuary.It was showed that pH and total alkalinity took on clear spatial variations in values with the minima in the low salinity region.Like salinity, transect distributions of pH and total alkalinity (TA) in a downriver direction had a sharp gradient each.These gradients appeared in such a sequence that the TA gradient was earlier than salinity and pH gradients, and the salinity gradient was earlier than the pH gradient.These distribution characteristics seemed to be strongly influenced by the mixing process of freshwater and seawater, for both pH and total alkalinity had significant linear relationships with salinity and temperature.For pH, phytoplankton activities also had a significant impact upon its spatial distribution.During a period of 48 h, pH and total alkalinity changed within wide ranges for every layer of the two anchor stations, namely, Stas 13 and 20, which were located at the mixed water mass and seawater mass, respectively.For both Stas 13 and 20, pH and TA fluctuation of every layer could be very wide during a 4 h period.As a whole, the data of the two anchor stations showed that neither variations in salinity and temperature nor phytoplankton activities were the main factors strongly influencing the total alkalinity temporal variability on a small time scale.The data of Sta.20 implied that both salinity variation and phytoplankton activities had a significant influence on pH temporal variability, but the same conclusion could not be drawn from the data of Sta.13.
2005, (5): 78-88.
Abstract:
Settling particulate matter (SPM) was collected by using sediment traps at four stations in a survey section from Qingdao to Cheju-do, across the Huanghai Sea cold water mass (HSCWM), in August 2002.The sediment traps were planted in three layers:the upper layer of the thermocline (ULT) above the HSCWM, the lower layer of the thermocline (LLT), and the bottom layer of water column (BL).To determine the particle flux, the contents of organic carbon (POC), organic nitrogen (PON), total carbon (PC), and total phosphorous(PP) in SPM were analyzed, and two flux models (Ⅰ and Ⅱ) were improved to calculate the resuspension ratio, with an assumption in Model Ⅰ that the vertical flux of SPM in the LLT equals the net vertical flux of SPM in the whole water column.An X value, i.e., the fraction of the resuspension flux originating from the surficial sediments nearby the sampling station, was deduced from Model Ⅰ to estimate the contribution of lateral currents to the total resuspension flux.The results showed that inorganic particles, fecal pellets, and miscellaneous aggregates were the major types of SPM in the HSCWM, and the contents of POC, PON, PC, and PP all decreased with water depth.A great deal of fecal pellets found in the LLT indicates that the main space producing biogenic SPM is the thermocline, and especially the LLT, where the C/N ratio is lower than that in the ULT.The resuspension ratios, 90%~96% among stations, imply strong impact ofresuspension on particle flux in the BL.These values were not significantly different between the two flux models, suggesting that the hypothesis in Model Ⅰ that the flux in the LLT equaling the net flux to the bottom is acceptable for shallow waters with stratification like the HSCWM.The POC export ratio from the HSCWM ranges from 35% to 68%.It benefits from the short sinking distance in shallow water.The upwelling in the HSCWM enhanced the POC flux through the water mass, and the lateral currents provides up to being greater than 50% ofresuspension flux in the BL according to evaluation of the X value.
Settling particulate matter (SPM) was collected by using sediment traps at four stations in a survey section from Qingdao to Cheju-do, across the Huanghai Sea cold water mass (HSCWM), in August 2002.The sediment traps were planted in three layers:the upper layer of the thermocline (ULT) above the HSCWM, the lower layer of the thermocline (LLT), and the bottom layer of water column (BL).To determine the particle flux, the contents of organic carbon (POC), organic nitrogen (PON), total carbon (PC), and total phosphorous(PP) in SPM were analyzed, and two flux models (Ⅰ and Ⅱ) were improved to calculate the resuspension ratio, with an assumption in Model Ⅰ that the vertical flux of SPM in the LLT equals the net vertical flux of SPM in the whole water column.An X value, i.e., the fraction of the resuspension flux originating from the surficial sediments nearby the sampling station, was deduced from Model Ⅰ to estimate the contribution of lateral currents to the total resuspension flux.The results showed that inorganic particles, fecal pellets, and miscellaneous aggregates were the major types of SPM in the HSCWM, and the contents of POC, PON, PC, and PP all decreased with water depth.A great deal of fecal pellets found in the LLT indicates that the main space producing biogenic SPM is the thermocline, and especially the LLT, where the C/N ratio is lower than that in the ULT.The resuspension ratios, 90%~96% among stations, imply strong impact ofresuspension on particle flux in the BL.These values were not significantly different between the two flux models, suggesting that the hypothesis in Model Ⅰ that the flux in the LLT equaling the net flux to the bottom is acceptable for shallow waters with stratification like the HSCWM.The POC export ratio from the HSCWM ranges from 35% to 68%.It benefits from the short sinking distance in shallow water.The upwelling in the HSCWM enhanced the POC flux through the water mass, and the lateral currents provides up to being greater than 50% ofresuspension flux in the BL according to evaluation of the X value.
2005, (5): 89-99.
Abstract:
Variations of the particulate organic carbon and nitrogen (POC/PN) along the PN section in the East China Sea (ECS) were examined based on POC/PN data obtained in September 2002.A comparison with others work indicates that POC is the highest in summer, followed by autumn and spring, and the lowest in winter.Generally, POC concentration decreases seawards, and the in situ productivity in September plays an important role in POC distribution.POC in the PN section is composed of terrestrial, resuspended, in situ produced carbon and carbon originated from the Kuroshio waters.The Changjiang River effects the ECS in the PN section, but the influence is mainly minimiged beyond 123.5° E because ofbarrier effect.The impact of Kuroshio subsurface water (KSSW) over shelf break can also effect POC distribution, with high POC concentration there.
Variations of the particulate organic carbon and nitrogen (POC/PN) along the PN section in the East China Sea (ECS) were examined based on POC/PN data obtained in September 2002.A comparison with others work indicates that POC is the highest in summer, followed by autumn and spring, and the lowest in winter.Generally, POC concentration decreases seawards, and the in situ productivity in September plays an important role in POC distribution.POC in the PN section is composed of terrestrial, resuspended, in situ produced carbon and carbon originated from the Kuroshio waters.The Changjiang River effects the ECS in the PN section, but the influence is mainly minimiged beyond 123.5° E because ofbarrier effect.The impact of Kuroshio subsurface water (KSSW) over shelf break can also effect POC distribution, with high POC concentration there.
2005, (5): 100-109.
Abstract:
Experiments on the effects of nitric oxide (NO) and iron on the growth of marine microalgae Skeletonema costatum were conducted.The results are as follows:exogenous NO could increase the growth rate of marine algae and raise the biomass remarkably under iron-deficient conditions.But it was a complicated process that the phytoplankton growth was influenced by NO and iron, which was controlled by the NO concentration, the nutrition level of the culture medium and the iron concentration, etc.Meanwhile, the iron concentration in the medium also has a direct influence on the growth and NO release capacity of the algae.Therefore, the effects of NO and iron on the growth of marine phytoplankton were mutual.
Experiments on the effects of nitric oxide (NO) and iron on the growth of marine microalgae Skeletonema costatum were conducted.The results are as follows:exogenous NO could increase the growth rate of marine algae and raise the biomass remarkably under iron-deficient conditions.But it was a complicated process that the phytoplankton growth was influenced by NO and iron, which was controlled by the NO concentration, the nutrition level of the culture medium and the iron concentration, etc.Meanwhile, the iron concentration in the medium also has a direct influence on the growth and NO release capacity of the algae.Therefore, the effects of NO and iron on the growth of marine phytoplankton were mutual.
2005, (5): 110-119.
Abstract:
Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas.Of which, one genus and six species are recorded for the first time from China's seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla)carnicolor, Ziba duplilirata, Z.insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata.
Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas.Of which, one genus and six species are recorded for the first time from China's seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla)carnicolor, Ziba duplilirata, Z.insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata.
2005, (5): 120-126.
Abstract:
The localization of nitric oxide synthases (NOS) is dealed with in the developing gonads of amphioxus Branchiostoma belcheri tsingtauense.It was found by NADPH-diaphorase staining that (1) NOS activity was present in the nuclear membranes of germinal vesicles during the entire period of oocyte development; (2) NOS was localized in both the nuclear membranes and the perinuclear region of cytoplasm in the vitellogenetic oocytes; (3) NOS was relocated in the cortical layer in the mature egg; (4) NOS activity was present in spermatocytes, but not in the spermatogonia in the middle of October; (5) NOS was detected in both spermatozoa and spermatids as well as spermatocytes during the breeding season.This is the first report on the distribution pattern of NOS in the developing gonads in protochordates.These results suggest a role for NOS in the functioning of the nuclear membranes and yolk synthesis during oogenesis and in cell division and differentiation during spermatogenesis.
The localization of nitric oxide synthases (NOS) is dealed with in the developing gonads of amphioxus Branchiostoma belcheri tsingtauense.It was found by NADPH-diaphorase staining that (1) NOS activity was present in the nuclear membranes of germinal vesicles during the entire period of oocyte development; (2) NOS was localized in both the nuclear membranes and the perinuclear region of cytoplasm in the vitellogenetic oocytes; (3) NOS was relocated in the cortical layer in the mature egg; (4) NOS activity was present in spermatocytes, but not in the spermatogonia in the middle of October; (5) NOS was detected in both spermatozoa and spermatids as well as spermatocytes during the breeding season.This is the first report on the distribution pattern of NOS in the developing gonads in protochordates.These results suggest a role for NOS in the functioning of the nuclear membranes and yolk synthesis during oogenesis and in cell division and differentiation during spermatogenesis.
2005, (5): 127-138.
Abstract:
A depth profile of bacterial community structure in one deep-sea sediment core of the western Pacific "warm pool" (WP) was investigated and compared with that in a sediment sample from the eastern Pacific (EP) by phylogenetic analysis of 16S rDNA fragments.Five bacterial 16S rDNA clone libraries were constructed, and t33 clones with different restriction fragment length polymorphism(RFLP) patterns were sequenced.A phylogenetic analysis of these sequences revealed that the bacterial diversity in a sample from the WP was more abundant than that in the EP sample.The bacterial population in the sediment core of WP was composed of eight major lineages of the domain bacteria.Among them the γ-Proteobacteria was the predominant and most diverse group in each section of WP sediment core, followed by the α-Proteobacteria.The genus Colwellia belonging to γ-Proteobacteria was predominant in this sample.The shift of bacterial communities among different sections of the WP sediment core was δ-, ε-Proteobacteria, and Cytopahga-Flexibacteria-Bacteroides (CFB) group.The ratios between them in the bacterial communities all showed inversely proportional to the depth of sediment.The sequences related to sulphate reducing bacteria (SRB) were detected in every section.The bacterial community structure in this sediment core might be related to the environmental characteristics of the surface seawater of the western Pacific WP.
A depth profile of bacterial community structure in one deep-sea sediment core of the western Pacific "warm pool" (WP) was investigated and compared with that in a sediment sample from the eastern Pacific (EP) by phylogenetic analysis of 16S rDNA fragments.Five bacterial 16S rDNA clone libraries were constructed, and t33 clones with different restriction fragment length polymorphism(RFLP) patterns were sequenced.A phylogenetic analysis of these sequences revealed that the bacterial diversity in a sample from the WP was more abundant than that in the EP sample.The bacterial population in the sediment core of WP was composed of eight major lineages of the domain bacteria.Among them the γ-Proteobacteria was the predominant and most diverse group in each section of WP sediment core, followed by the α-Proteobacteria.The genus Colwellia belonging to γ-Proteobacteria was predominant in this sample.The shift of bacterial communities among different sections of the WP sediment core was δ-, ε-Proteobacteria, and Cytopahga-Flexibacteria-Bacteroides (CFB) group.The ratios between them in the bacterial communities all showed inversely proportional to the depth of sediment.The sequences related to sulphate reducing bacteria (SRB) were detected in every section.The bacterial community structure in this sediment core might be related to the environmental characteristics of the surface seawater of the western Pacific WP.
2005, (5): 139-144.
Abstract:
Genomic DNA was extracted from hypnospores of Perkinsus-like parasite of Manila clam Ruditapes philippinarum collected at the fishing grounds in Huanghai Sea coast Shicheng Island and East China Sea coast Ningbo, China.The internal transcribed spacer(ITS)in rDNA was PCR-amplified, cloned, sequenced, and compared with that of five Perkinsus species in GenBank.The fragment amplified from DNA of parasite of either Shicheng Island or Ningbo contained 649 bp, including partial ssrRNA(51 bp) and ITS(+5.8 S)(598 bp) regions.The ITS(+5.8S) sequences of Perkinsus-like parasite of both Shicheng Island and Ningbo were all 99% identical to those of Perkinsus atlanticus, and were not more than 95% identical to those of other four Perkinsus species including P.marinus, P.andrewsi, P.andrewsi and P.medierraneus.The ITS (+5.8S) sequence of Perkinsus-like parasite of Shicheng Island was 99% identical to that of Ningbo.These facts about nucleotide sequences suggested that the Perkinsus-like parasite in Manila clam, Ruditapes philippinarum collected from either the Huanghai Sea coast or the East China Sea coast was P.atlanticus, and might reflect P.atlanticus strains of distinct geographic distribution.
Genomic DNA was extracted from hypnospores of Perkinsus-like parasite of Manila clam Ruditapes philippinarum collected at the fishing grounds in Huanghai Sea coast Shicheng Island and East China Sea coast Ningbo, China.The internal transcribed spacer(ITS)in rDNA was PCR-amplified, cloned, sequenced, and compared with that of five Perkinsus species in GenBank.The fragment amplified from DNA of parasite of either Shicheng Island or Ningbo contained 649 bp, including partial ssrRNA(51 bp) and ITS(+5.8 S)(598 bp) regions.The ITS(+5.8S) sequences of Perkinsus-like parasite of both Shicheng Island and Ningbo were all 99% identical to those of Perkinsus atlanticus, and were not more than 95% identical to those of other four Perkinsus species including P.marinus, P.andrewsi, P.andrewsi and P.medierraneus.The ITS (+5.8S) sequence of Perkinsus-like parasite of Shicheng Island was 99% identical to that of Ningbo.These facts about nucleotide sequences suggested that the Perkinsus-like parasite in Manila clam, Ruditapes philippinarum collected from either the Huanghai Sea coast or the East China Sea coast was P.atlanticus, and might reflect P.atlanticus strains of distinct geographic distribution.
2005, (5): 145-149.
Abstract:
Response surface methodology was used to optimize a medium for a red-pigmented marine bacterium S-9801 strain (Flavobacterium sp.).In the first optimization step the influence of yeast extract, peptone, glucose and sodium chloride on pigment production was evaluated using a fractional factorial design.Pigment production was positively influenced by glucose and sodium chloride while other components had no significant effect.In the second step the path of steepest ascent was used to approach the optimal region of the medium composition.In the third step the optimal concentration of glucose and sodium chloride was determined by a central composite design and response analysis.The optimized medium allowed pigment production (A535~650) to be increased from 0.137 to 0.559, being 320% higher than the original medium.
Response surface methodology was used to optimize a medium for a red-pigmented marine bacterium S-9801 strain (Flavobacterium sp.).In the first optimization step the influence of yeast extract, peptone, glucose and sodium chloride on pigment production was evaluated using a fractional factorial design.Pigment production was positively influenced by glucose and sodium chloride while other components had no significant effect.In the second step the path of steepest ascent was used to approach the optimal region of the medium composition.In the third step the optimal concentration of glucose and sodium chloride was determined by a central composite design and response analysis.The optimized medium allowed pigment production (A535~650) to be increased from 0.137 to 0.559, being 320% higher than the original medium.
2005, (5): 150-161.
Abstract:
The partial sequence of the rbcL from Bryopsis hypnoides, including the sequences of the upstream, extron and partial intron, was amplified by PCR and their sequences were determined.With Spinacia oleracea as the outgroup, neighbor-joining method and maximum parsimony method were used respectively to build phylogenetic trees according to the rbcL exon sequence among 13species that were the typical species of six phyla.Two kinds of trees showed clearly that there were two groups among those species, the green lineage and the non-green lineage.And the relationships of algae in the green lineage were similar in the two trees but those in the non-green lineage were not consistent.Analysis of codon preference indicated that the codon preference of the rbcL exon of Bryopsis hypnoides distinctly differed from that of the relevant sequence of photosynthetic bacteria.
The partial sequence of the rbcL from Bryopsis hypnoides, including the sequences of the upstream, extron and partial intron, was amplified by PCR and their sequences were determined.With Spinacia oleracea as the outgroup, neighbor-joining method and maximum parsimony method were used respectively to build phylogenetic trees according to the rbcL exon sequence among 13species that were the typical species of six phyla.Two kinds of trees showed clearly that there were two groups among those species, the green lineage and the non-green lineage.And the relationships of algae in the green lineage were similar in the two trees but those in the non-green lineage were not consistent.Analysis of codon preference indicated that the codon preference of the rbcL exon of Bryopsis hypnoides distinctly differed from that of the relevant sequence of photosynthetic bacteria.
