2007 Vol. 26, No. 2
column
Display Method:
2007, (2): 1-11.
Abstract:
The circulation in the Shikoku Basin plays a very important role in the pathway of the Kuroshio and the water exchange in the subtropical gyre in the North Pacific Ocean.The Argo profiling floats deployed in the Shikoku Basin are used to study the circulations and water masses in the basin.The trajectories and parking depth velocity fields derived from all Argo floats show an anticyclonic circulation at 2 000 m in the Shikoku Basin.There are inhanced eddy activities in the Shikoku Basin, which have large influence on the Shikoku Basin circulation patterns.The characteristics of temperature-salinity curves indicate that there are North Pacific Ocean tropical water (NPTW), North Pacific Ocean subtropical mode water (NPSTMW) and North Pacific Ocean intermediate water (NPIW) in the Shikoku Basin.The NPTW is only exists south of 32°N.In the middle part of the basin, which is 28°~31°N, 133°~135°E, there is a confluence region.Water masses coming from the Kuroshio mix with the water in the Shikoku Basin.
The circulation in the Shikoku Basin plays a very important role in the pathway of the Kuroshio and the water exchange in the subtropical gyre in the North Pacific Ocean.The Argo profiling floats deployed in the Shikoku Basin are used to study the circulations and water masses in the basin.The trajectories and parking depth velocity fields derived from all Argo floats show an anticyclonic circulation at 2 000 m in the Shikoku Basin.There are inhanced eddy activities in the Shikoku Basin, which have large influence on the Shikoku Basin circulation patterns.The characteristics of temperature-salinity curves indicate that there are North Pacific Ocean tropical water (NPTW), North Pacific Ocean subtropical mode water (NPSTMW) and North Pacific Ocean intermediate water (NPIW) in the Shikoku Basin.The NPTW is only exists south of 32°N.In the middle part of the basin, which is 28°~31°N, 133°~135°E, there is a confluence region.Water masses coming from the Kuroshio mix with the water in the Shikoku Basin.
2007, (2): 12-25.
Abstract:
Data from three cruises conducted in the Zhujiang River (ZR), coastal waters of Guangdong (CWGD) and the northern South China Sea (NSCS) during 2003 and 2004 were examined for assessing the relative importance of pigment composition and packaging effect in modifying the specific absorption coefficients of phytoplankton.The three survey regions differ widely in their phytoplankton community with large cells dominating the ZR and CWGD waters and small cells dominating the NSCS region.Variations in the size structure and the accessory pigments have much effect on the chlorophyll a-specific absorption coefficient of phytoplankton.The size index accounted for about 42% and 33% of the variation of the specific absorption coefficient at 440 and 675 nm, respectively.Using the multiple regression analysis approach, pigment concentrations for each sample were calculated.The accessory pigments other than chlorophyll a contribute to absorption mainly in the blue-to-green region of the spectrum and their absorptions account for about 44%, 43% and 53% on the average of the total phytoplankton absorption at 440 nm for the ZR, CWGD and NSCS regions.Among the accessory pigments, the photosynthetic carotenoids (noted PSC) play a dominant role in the ZR and CWGD waters, while in the NSCS the nonphotosynthetic carotenoids (noted PPC) as well as PSC have important contributions.Because the variations of both the size structure and accessory pigments in algal populations contributed to the variability of the specific absorption coefficient in the study regions, these factors may be considered explicitly in future bio-optical algorithms to derive chlorophyll a concentration more accurately.
Data from three cruises conducted in the Zhujiang River (ZR), coastal waters of Guangdong (CWGD) and the northern South China Sea (NSCS) during 2003 and 2004 were examined for assessing the relative importance of pigment composition and packaging effect in modifying the specific absorption coefficients of phytoplankton.The three survey regions differ widely in their phytoplankton community with large cells dominating the ZR and CWGD waters and small cells dominating the NSCS region.Variations in the size structure and the accessory pigments have much effect on the chlorophyll a-specific absorption coefficient of phytoplankton.The size index accounted for about 42% and 33% of the variation of the specific absorption coefficient at 440 and 675 nm, respectively.Using the multiple regression analysis approach, pigment concentrations for each sample were calculated.The accessory pigments other than chlorophyll a contribute to absorption mainly in the blue-to-green region of the spectrum and their absorptions account for about 44%, 43% and 53% on the average of the total phytoplankton absorption at 440 nm for the ZR, CWGD and NSCS regions.Among the accessory pigments, the photosynthetic carotenoids (noted PSC) play a dominant role in the ZR and CWGD waters, while in the NSCS the nonphotosynthetic carotenoids (noted PPC) as well as PSC have important contributions.Because the variations of both the size structure and accessory pigments in algal populations contributed to the variability of the specific absorption coefficient in the study regions, these factors may be considered explicitly in future bio-optical algorithms to derive chlorophyll a concentration more accurately.
2007, (2): 26-35.
Abstract:
Coral reefs are an sensitive-to-environment complex marine ecosystem.The ecosystem of corals is rich in biodiversity.Remote sensing offers a powerful tool for categorizing coral reefs and is the most cost-effective approach for the large-scale reef survey.The Dongsha Atoll, more than 300 km2 with an average depth of 10 m, is located at the northern continental margin of the South China Sea.It has been abused by destructive fishing during recent decades.Three satellite imageries (Quickbird2, ETM+ and SPOT5) are used to evaluate the capabilities of SPOT5 imagery to provide data that are useful for categorizing the current distribution of coral reefs therein.During the data processing, unsupervised classification functions are adopted for ETM+ and SPOT5 data, while the supervised classification method is used for Quickbird2.The classes are (or not) merged into coral reef, and then will be operated by vectorization, simplification, and topological analysis.There are 1 331 coral reefs larger than 100 m2 with a detection limit of 3×3 pixels at the multi-band data of Quickbird2, which is taken as the comparison baseline.The results extracted from SPOT5 and ETM images are less in number and area than those from the Quickbird2 image, whereas the results from SPOT5 data are better than those of ETM data at the silty lagoon due to its higher resolution.SPOT5 XS band 2 fails to distinguish the deep substrate inside the atoll compared with ETM data because of its poor penetration capability.Only SPOT XS band 1 cannot be used to differentiate coral reef from sand bottom.Merging the SPOT5 multi-bands data with the spatial resolution of SPOT5 pan-data and referring to ETM imagery are expected to provide an optimal satellite-based approach for mapping of coral reefs.
Coral reefs are an sensitive-to-environment complex marine ecosystem.The ecosystem of corals is rich in biodiversity.Remote sensing offers a powerful tool for categorizing coral reefs and is the most cost-effective approach for the large-scale reef survey.The Dongsha Atoll, more than 300 km2 with an average depth of 10 m, is located at the northern continental margin of the South China Sea.It has been abused by destructive fishing during recent decades.Three satellite imageries (Quickbird2, ETM+ and SPOT5) are used to evaluate the capabilities of SPOT5 imagery to provide data that are useful for categorizing the current distribution of coral reefs therein.During the data processing, unsupervised classification functions are adopted for ETM+ and SPOT5 data, while the supervised classification method is used for Quickbird2.The classes are (or not) merged into coral reef, and then will be operated by vectorization, simplification, and topological analysis.There are 1 331 coral reefs larger than 100 m2 with a detection limit of 3×3 pixels at the multi-band data of Quickbird2, which is taken as the comparison baseline.The results extracted from SPOT5 and ETM images are less in number and area than those from the Quickbird2 image, whereas the results from SPOT5 data are better than those of ETM data at the silty lagoon due to its higher resolution.SPOT5 XS band 2 fails to distinguish the deep substrate inside the atoll compared with ETM data because of its poor penetration capability.Only SPOT XS band 1 cannot be used to differentiate coral reef from sand bottom.Merging the SPOT5 multi-bands data with the spatial resolution of SPOT5 pan-data and referring to ETM imagery are expected to provide an optimal satellite-based approach for mapping of coral reefs.
2007, (2): 36-48.
Abstract:
Particulate samples were collected from the Changjiang river system during a flood period, in May 1997, and POC, stable isotope and lipids associated with particles were examined.Results showed the decrease (0.84%~1.88%) of organic carbon content from the upper reaches to the estuary.δ13C values of particulate organic carbon was in the range of -24.9×10-3 to -26.6×10-3, which were close to the isotopic signature of continental C3 vegetation.Total particulate n-alkanes concentrations varied from 1.4 to 10.1 μg/dm3, or from 23.7 to 107 μg/g of total suspended matter.Fatty acids were present in all the samples, from 1.4 to 5.4 μg/dm3, with saturated and unsaturated straight-chain and branched compounds in the carbon number range from C12 to C30.Both δ13C and the ratio of carbon content to nitrogen content indicate the predominance of terrestrial inputs (soil organic matter) among the particles.The biomarker approach has been used to identify the relative portion of terrigenous and autochthonous fraction in the particulate samples.The distribution of fatty acids suggests a striking phytoplanktonic and microbial signal in most particle samples.The terrestrial alkanes are used to estimate the contribution of terrestrial inputs along the mainstream.
Particulate samples were collected from the Changjiang river system during a flood period, in May 1997, and POC, stable isotope and lipids associated with particles were examined.Results showed the decrease (0.84%~1.88%) of organic carbon content from the upper reaches to the estuary.δ13C values of particulate organic carbon was in the range of -24.9×10-3 to -26.6×10-3, which were close to the isotopic signature of continental C3 vegetation.Total particulate n-alkanes concentrations varied from 1.4 to 10.1 μg/dm3, or from 23.7 to 107 μg/g of total suspended matter.Fatty acids were present in all the samples, from 1.4 to 5.4 μg/dm3, with saturated and unsaturated straight-chain and branched compounds in the carbon number range from C12 to C30.Both δ13C and the ratio of carbon content to nitrogen content indicate the predominance of terrestrial inputs (soil organic matter) among the particles.The biomarker approach has been used to identify the relative portion of terrigenous and autochthonous fraction in the particulate samples.The distribution of fatty acids suggests a striking phytoplanktonic and microbial signal in most particle samples.The terrestrial alkanes are used to estimate the contribution of terrestrial inputs along the mainstream.
2007, (2): 49-55.
Abstract:
Sea surface temperatures (SSTs) in the southwestern South China Sea have been reconstructed for the past 160 ka using the U37k paleothermometer from the core MD01-2392.The temperature differences between glacial times (MISs 6 and 2) and interglacial times (MISs 5.5 and 1) are 2.2~2.5℃.Younger Dryas event during the last deglaciation was documented in both the planktonic foraminiferal δ18O and SST records.After MIS 5.5, SSTs displayed a progressive cooling from 28.6 to 24.5℃, culminating at the LGM.During this gradual cooling period, warm events such as MISs 5.3, 5.1 and 3 were also clearly documented.By comparison of SST between the study core and Core 17954, a pattern of low or no meridional SST gradients during the interglacial periods and high meridional SST gradients during the glacial periods was exhibited.This pattern indicates the much stronger East Asian winter monsoon at the glacial than at the interglacial periods.Spectral analysis gives two prominent cycles:41 and 23 ka, with the former more pronounced, suggesting that SSTs in the southern SCS varied in concert with high-latitude processes through the connection of East Asian winter monsoon.
Sea surface temperatures (SSTs) in the southwestern South China Sea have been reconstructed for the past 160 ka using the U37k paleothermometer from the core MD01-2392.The temperature differences between glacial times (MISs 6 and 2) and interglacial times (MISs 5.5 and 1) are 2.2~2.5℃.Younger Dryas event during the last deglaciation was documented in both the planktonic foraminiferal δ18O and SST records.After MIS 5.5, SSTs displayed a progressive cooling from 28.6 to 24.5℃, culminating at the LGM.During this gradual cooling period, warm events such as MISs 5.3, 5.1 and 3 were also clearly documented.By comparison of SST between the study core and Core 17954, a pattern of low or no meridional SST gradients during the interglacial periods and high meridional SST gradients during the glacial periods was exhibited.This pattern indicates the much stronger East Asian winter monsoon at the glacial than at the interglacial periods.Spectral analysis gives two prominent cycles:41 and 23 ka, with the former more pronounced, suggesting that SSTs in the southern SCS varied in concert with high-latitude processes through the connection of East Asian winter monsoon.
2007, (2): 56-64.
Abstract:
Temporal and spatial variations of the back-silting strength in the north passage channel of Changjiang Estuary are investigated using the empirical orthogonal function (EOF) method, with the aim to determine the imposed processes and time-scales.Data on back-silting quantity in every dredging unit of the channel have been collected since March 2000, predominantly once 15 d.The EOF analysis of the back-silting strength reveals two significant modes, which totally explain 58.33% of the overall variance, and the corresponding processes and time-scales.The first EOF mode shows a clear annual cycle which is determined by the riverine water and sediment discharge from the upstream.The second EOF mode reveals a close relation between the back-silting strength and project activities.Because the processes are greatly interrelated in this study case, the other EOF modes accounting for 41.67% of the total variance do not show clear processes and time-scales.
Temporal and spatial variations of the back-silting strength in the north passage channel of Changjiang Estuary are investigated using the empirical orthogonal function (EOF) method, with the aim to determine the imposed processes and time-scales.Data on back-silting quantity in every dredging unit of the channel have been collected since March 2000, predominantly once 15 d.The EOF analysis of the back-silting strength reveals two significant modes, which totally explain 58.33% of the overall variance, and the corresponding processes and time-scales.The first EOF mode shows a clear annual cycle which is determined by the riverine water and sediment discharge from the upstream.The second EOF mode reveals a close relation between the back-silting strength and project activities.Because the processes are greatly interrelated in this study case, the other EOF modes accounting for 41.67% of the total variance do not show clear processes and time-scales.
2007, (2): 65-74.
Abstract:
Through exploring the microsatellite primers from the random genome sequences of Chinese shrimp (Fenneropenaeus chinensis), some microsatellite primers were obtained with rich polymorphic genetic information, and a triplex PCR was established using three primers (RS1101, RS0683 and H081 primers).By adjusting the final concentration of Mg2+, dNTP and primers, and using a touch-town PCR program, the optimum amplification parameters of PCR system were obtained, which could successfully amplify the three primers in a PCR reaction.In the denatured PAGE gel, the amplified DNA fragments of three primers RS1101, RS0683 and H081 could be easily identified each other.For the triplex PCR system, the PPE (probabilities of paternity exclusion) is 0.967 9, and the DP (discrimination power) is 0.999 327.Using the triplex PCR to test ten individuals of a parentage and their parents, an individual was excluded from the parentage in all of the three microsatellite loci, which might be mixed into the parentage for some unknown reason such as factitious misplay.The triplex PCR will be of great practical value in identifying the parentages of F.chinensis.
Through exploring the microsatellite primers from the random genome sequences of Chinese shrimp (Fenneropenaeus chinensis), some microsatellite primers were obtained with rich polymorphic genetic information, and a triplex PCR was established using three primers (RS1101, RS0683 and H081 primers).By adjusting the final concentration of Mg2+, dNTP and primers, and using a touch-town PCR program, the optimum amplification parameters of PCR system were obtained, which could successfully amplify the three primers in a PCR reaction.In the denatured PAGE gel, the amplified DNA fragments of three primers RS1101, RS0683 and H081 could be easily identified each other.For the triplex PCR system, the PPE (probabilities of paternity exclusion) is 0.967 9, and the DP (discrimination power) is 0.999 327.Using the triplex PCR to test ten individuals of a parentage and their parents, an individual was excluded from the parentage in all of the three microsatellite loci, which might be mixed into the parentage for some unknown reason such as factitious misplay.The triplex PCR will be of great practical value in identifying the parentages of F.chinensis.
2007, (2): 75-83.
Abstract:
A rebuilt vector pCANTAB 5 EE was obtained by inserting a 34 bp double-stranded oligonucleotide which contained a EcoRV recognition sequence into pCANTAB 5 E.White spot syndrome virus (WSSV) genome DNA was fragmented by sonication to isolate fragments mainly in the range of 0.8~2.0 kb, then the fragments were blunt-ended with T4 DNA polymerase and cloned into the EcoRV site of pCANTAB 5 EE.The primary recombinant clone of the library was 3.0×105.Colony PCR of random selected recombinants showed that the size of the inserts was 0.12~1.77 kb.After the whole library recombinant phages infected Escherichia coli HB2151 cells, the extracellular and periplasmic extracts were dropped on PVDF membranes to perform dot blot, using polyclonal mouse anti-VP24 serum, anti-WSV026 serum, anti-WSV063 serum, anti-WSV069 serum, anti-WSV112 serum, anti-WSV238 serum, anti-WSV303 serum and anti-VP26 serum as the primary antibody, respectively.The results showed that the display library could express the viral proteins.
A rebuilt vector pCANTAB 5 EE was obtained by inserting a 34 bp double-stranded oligonucleotide which contained a EcoRV recognition sequence into pCANTAB 5 E.White spot syndrome virus (WSSV) genome DNA was fragmented by sonication to isolate fragments mainly in the range of 0.8~2.0 kb, then the fragments were blunt-ended with T4 DNA polymerase and cloned into the EcoRV site of pCANTAB 5 EE.The primary recombinant clone of the library was 3.0×105.Colony PCR of random selected recombinants showed that the size of the inserts was 0.12~1.77 kb.After the whole library recombinant phages infected Escherichia coli HB2151 cells, the extracellular and periplasmic extracts were dropped on PVDF membranes to perform dot blot, using polyclonal mouse anti-VP24 serum, anti-WSV026 serum, anti-WSV063 serum, anti-WSV069 serum, anti-WSV112 serum, anti-WSV238 serum, anti-WSV303 serum and anti-VP26 serum as the primary antibody, respectively.The results showed that the display library could express the viral proteins.
2007, (2): 84-93.
Abstract:
A novel potent protease, Urechis unicinctus fibrinolytic enzyme (UFE), was firstly discovered.The enzymatic properties of UFE were further investigated.As a low molecular mass protein, UFE appeared to be very stable to heat and pH.When temperature was below 50℃, the remnant enzyme activity remained almost unchanged, but when temperature was raised to 60℃, the remnant enzyme activity began to decrease rapidly.UFE was quite stable in the range of pH value from 3 to 12, especially in slightly alkaline pH value.Mn2+, Cu2+ and Fe2+ ions were activators of UFE, while Fe3+ and Ag+ ions were inhibitors of UFE.Fe2+ ion along with Fe3+ ion might regulate UFE activity in vivo.The optimum pH and temperature of UFE were about 8 and 50℃, respectively.Other characteristics of this enzyme were also studied.Systematic research results are significant when UFE is applied for medical and industrial purposes.
A novel potent protease, Urechis unicinctus fibrinolytic enzyme (UFE), was firstly discovered.The enzymatic properties of UFE were further investigated.As a low molecular mass protein, UFE appeared to be very stable to heat and pH.When temperature was below 50℃, the remnant enzyme activity remained almost unchanged, but when temperature was raised to 60℃, the remnant enzyme activity began to decrease rapidly.UFE was quite stable in the range of pH value from 3 to 12, especially in slightly alkaline pH value.Mn2+, Cu2+ and Fe2+ ions were activators of UFE, while Fe3+ and Ag+ ions were inhibitors of UFE.Fe2+ ion along with Fe3+ ion might regulate UFE activity in vivo.The optimum pH and temperature of UFE were about 8 and 50℃, respectively.Other characteristics of this enzyme were also studied.Systematic research results are significant when UFE is applied for medical and industrial purposes.
2007, (2): 94-105.
Abstract:
In order to study the effect of internal flow on vortex-induced vibration of flexible riser, the experiment on the vortex-induced vibration of flexible riser transporting fluid in the current was conducted in the physical oceanography laboratory of Ocean University of China.Considering the internal flowing fluid and external marine environment, the dynamic response of the flexible riser was measured.The corresponding numerical simulation was performed using the wake oscillatory model considering the extensibility of the riser system.Both the experiment and the numerical simulation indicated that with the increase of internal flow speed, the response amplitude increases, while the response frequency decreases.
In order to study the effect of internal flow on vortex-induced vibration of flexible riser, the experiment on the vortex-induced vibration of flexible riser transporting fluid in the current was conducted in the physical oceanography laboratory of Ocean University of China.Considering the internal flowing fluid and external marine environment, the dynamic response of the flexible riser was measured.The corresponding numerical simulation was performed using the wake oscillatory model considering the extensibility of the riser system.Both the experiment and the numerical simulation indicated that with the increase of internal flow speed, the response amplitude increases, while the response frequency decreases.
2007, (2): 106-114.
Abstract:
On the basis of the previous studies, the simplest hyperbolic mild-slope equation has been gained and the linear time-dependent numerical model for the water wave propagation has been established combined with different boundary conditions.Through computing the effective surface displacement and transforming into the real transient wave motion, related wave factors will be calculated.Compared with Lin's model, analysis shows that calculation stability of the present model is enhanced efficiently, because the truncation errors of this model are only contributed by the dissipation terms, but those of Lin's model are induced by the convection terms, dissipation terms and source terms.The tests show that the present model succeeds the merit in Lin's model and the computational program is simpler, the computational time is shorter, and the computational stability is enhanced efficiently.The present model has the capability of simulating transient wave motion by correctly predicting at the speed of wave propagation, which is important for the real-time forecast of the arrival time of surface waves generated in the deep sea.The model is validated against analytical solution for wave diffraction and experimental data for combined wave refraction and diffraction over a submerged elliptic shoal on a slope.Good agreements are obtained.The model can be applied to the theory research an d engineering applications about the wave propagation in a biggish area.
On the basis of the previous studies, the simplest hyperbolic mild-slope equation has been gained and the linear time-dependent numerical model for the water wave propagation has been established combined with different boundary conditions.Through computing the effective surface displacement and transforming into the real transient wave motion, related wave factors will be calculated.Compared with Lin's model, analysis shows that calculation stability of the present model is enhanced efficiently, because the truncation errors of this model are only contributed by the dissipation terms, but those of Lin's model are induced by the convection terms, dissipation terms and source terms.The tests show that the present model succeeds the merit in Lin's model and the computational program is simpler, the computational time is shorter, and the computational stability is enhanced efficiently.The present model has the capability of simulating transient wave motion by correctly predicting at the speed of wave propagation, which is important for the real-time forecast of the arrival time of surface waves generated in the deep sea.The model is validated against analytical solution for wave diffraction and experimental data for combined wave refraction and diffraction over a submerged elliptic shoal on a slope.Good agreements are obtained.The model can be applied to the theory research an d engineering applications about the wave propagation in a biggish area.
2007, (2): 115-122.
Abstract:
An analytic method is used to study the reflection and transmission coefficients of the double submerged rectangular blocks (DSRBs) in oblique waves.The scattering potentials are obtained by means of the eigenfunction expansion method, and expressions for the reflection and transmission coefficients are determined.The boundary element method is employed to verify the correctness of the present analytical method.The DSRBs have better performance than the single submerged rectangular block (SSRB) in certain cases.The reflection and transmission properties of the DSRBs are investigated for some specific cases, and the influences of the geometric parameters are also presented.
An analytic method is used to study the reflection and transmission coefficients of the double submerged rectangular blocks (DSRBs) in oblique waves.The scattering potentials are obtained by means of the eigenfunction expansion method, and expressions for the reflection and transmission coefficients are determined.The boundary element method is employed to verify the correctness of the present analytical method.The DSRBs have better performance than the single submerged rectangular block (SSRB) in certain cases.The reflection and transmission properties of the DSRBs are investigated for some specific cases, and the influences of the geometric parameters are also presented.
2007, (2): 123-132.
Abstract:
This study examined the concentrations of polycyclic aromatic hydrocarbons (PAHs) in surface sediments collected in July 2004 from eight stations in the Zhelin Bay, one of the most important bays for large-scale mariculture in Guangdong Province.Thirteen individual parent PAH compounds were identified using high performance liquid chromatography with UV detection.The overall average concentration of total PAHs was 477.0 ng/g, ranging from 146.1 to 928.8 ng/g.Low molecular mass PAHs with two to three rings (e.g., acenaphthene) were dominant in each sample.The PAH concentration varied among sampling stations, with the highest concentration observed at bay outlets and the lowest found at stations outside the bay.Ratios of low to high molecular mass PAHs and fluoranthene to pyrene were used to determine the origin of PAHs, and results indicated mainly petroleum-derived contamination.Compared with other bays and harbors around the world, the total concentrations of PAHs in surface sediments at the Zhelin Bay are moderate, but this does not exclude the possibility of potential impact on human consumers because some strong carcinogenic PAHs with high molecular mass were found at the station with a nearby caged-fish and oyster farm.Long-term monitoring of PAH contamination in the Zhelin Bay is recommended to reduce the potential toxicological effects on aquatic organisms and humans.
This study examined the concentrations of polycyclic aromatic hydrocarbons (PAHs) in surface sediments collected in July 2004 from eight stations in the Zhelin Bay, one of the most important bays for large-scale mariculture in Guangdong Province.Thirteen individual parent PAH compounds were identified using high performance liquid chromatography with UV detection.The overall average concentration of total PAHs was 477.0 ng/g, ranging from 146.1 to 928.8 ng/g.Low molecular mass PAHs with two to three rings (e.g., acenaphthene) were dominant in each sample.The PAH concentration varied among sampling stations, with the highest concentration observed at bay outlets and the lowest found at stations outside the bay.Ratios of low to high molecular mass PAHs and fluoranthene to pyrene were used to determine the origin of PAHs, and results indicated mainly petroleum-derived contamination.Compared with other bays and harbors around the world, the total concentrations of PAHs in surface sediments at the Zhelin Bay are moderate, but this does not exclude the possibility of potential impact on human consumers because some strong carcinogenic PAHs with high molecular mass were found at the station with a nearby caged-fish and oyster farm.Long-term monitoring of PAH contamination in the Zhelin Bay is recommended to reduce the potential toxicological effects on aquatic organisms and humans.
2007, (2): 133-139.
Abstract:
Gene specific primers and DNA probe were designed based on the sequence of 18S rDNA cloned from the red tide alga Thalassiosira rotula.A real-time fluorescent quantitative PCR (RFQ-PCR) method was developed for quantitative detection of T.rotula.The RFQ-PCR assay data showed that the results obtained with the RFQ-PCR quite good agreement with those with the light microscope (LM) counting method, which suggested that the RFQ-PCR could be a useful method for red tide alga detection.
Gene specific primers and DNA probe were designed based on the sequence of 18S rDNA cloned from the red tide alga Thalassiosira rotula.A real-time fluorescent quantitative PCR (RFQ-PCR) method was developed for quantitative detection of T.rotula.The RFQ-PCR assay data showed that the results obtained with the RFQ-PCR quite good agreement with those with the light microscope (LM) counting method, which suggested that the RFQ-PCR could be a useful method for red tide alga detection.
2007, (2): 140-143.
Abstract:
Coral mucus covers the surface of coral and contains antibacterial substances as a first line of defense.Coral mucus not only enables the coral itself to resist disease, but also provides antibacterial agents for people.We collected mucus from a scleractinian coral (Symphyllia gigantea) at Sta.Sanya (China), then extracted the antibacterial substances using 10% glacial acetic acid with the help of antiprotease inhibitors, and tested the antibacterial activity by a terrestrial bacterium (Staphylococcus aureus) and a marine bacterium (Vibrio anguillarum).The result showed that, there were antibacterial agents in the mucus, and their antibacterial activities were lost by treatment of the sample at 90℃ water for 10 min.
Coral mucus covers the surface of coral and contains antibacterial substances as a first line of defense.Coral mucus not only enables the coral itself to resist disease, but also provides antibacterial agents for people.We collected mucus from a scleractinian coral (Symphyllia gigantea) at Sta.Sanya (China), then extracted the antibacterial substances using 10% glacial acetic acid with the help of antiprotease inhibitors, and tested the antibacterial activity by a terrestrial bacterium (Staphylococcus aureus) and a marine bacterium (Vibrio anguillarum).The result showed that, there were antibacterial agents in the mucus, and their antibacterial activities were lost by treatment of the sample at 90℃ water for 10 min.
2007, (2): 144-149.
Abstract:
The effects on ethoxyresorufin O-deethylase (EROD), NADPH-cytochrome c reductase and NADH cytochrome b5 reductase activities of digestive gland in Meretrix meretrix exposed to tributyltin (TBT) at environmental levels (0.1, 1.0, 10.0 ng/dm3 as stannum concentration), in experimental condition, were evaluated.The EROD, NADH cytochrome b5 reductase activities were significantly inhibited after exposure to 10.0 ng/dm3 TBT for 8 and 20 d, the NADPH cytochrome c reductase activities were significantly inhibited after exposure to 0.1, 1.0 and 10.0 ng/dm3 TBT for 8 d and to 1.0 and 10.0 ng/dm3 for 20 d, as compared with the matched control, while NADH cytochrome b5 reductases and NADPH cytochrome c reductase activities were induced after exposure to 10.0 ng/dm3 TBT for 2 d.The EROD activity in the 10 ng/dm3 group, and the NADH cytochrome b5 reductases activities in 1.0 and 10.0 ng/dm3 groups, were significantly induced when transferred to clean recovery tanks for 7 d.The three enzymic activities in the clams exposed to TBT were recovered to the level corresponding to that of the control group after transfer to clean recovery tanks for 20 d.NADPH cytochrome c reductase activity in Meretrix meretrix seems to be more sensitive to exposure of TBT than that of the EROD and NADH cytochrome b5 reductases.The results suggest that induction and inhibition by TBT to the monooxygenase system enzymic activity in Meretrix meretrix would simultaneously exist.The enzymic activities were inhibited by exposure for a long time.The results suggest that inhibition of the monooxygenase system should be an indication of the exposure to environmentally relevant concentrations of TBT for a long time.
The effects on ethoxyresorufin O-deethylase (EROD), NADPH-cytochrome c reductase and NADH cytochrome b5 reductase activities of digestive gland in Meretrix meretrix exposed to tributyltin (TBT) at environmental levels (0.1, 1.0, 10.0 ng/dm3 as stannum concentration), in experimental condition, were evaluated.The EROD, NADH cytochrome b5 reductase activities were significantly inhibited after exposure to 10.0 ng/dm3 TBT for 8 and 20 d, the NADPH cytochrome c reductase activities were significantly inhibited after exposure to 0.1, 1.0 and 10.0 ng/dm3 TBT for 8 d and to 1.0 and 10.0 ng/dm3 for 20 d, as compared with the matched control, while NADH cytochrome b5 reductases and NADPH cytochrome c reductase activities were induced after exposure to 10.0 ng/dm3 TBT for 2 d.The EROD activity in the 10 ng/dm3 group, and the NADH cytochrome b5 reductases activities in 1.0 and 10.0 ng/dm3 groups, were significantly induced when transferred to clean recovery tanks for 7 d.The three enzymic activities in the clams exposed to TBT were recovered to the level corresponding to that of the control group after transfer to clean recovery tanks for 20 d.NADPH cytochrome c reductase activity in Meretrix meretrix seems to be more sensitive to exposure of TBT than that of the EROD and NADH cytochrome b5 reductases.The results suggest that induction and inhibition by TBT to the monooxygenase system enzymic activity in Meretrix meretrix would simultaneously exist.The enzymic activities were inhibited by exposure for a long time.The results suggest that inhibition of the monooxygenase system should be an indication of the exposure to environmentally relevant concentrations of TBT for a long time.
2007, (2): 150-156.
Abstract:
Intracytoplasmic infection with a prokaryotic mycoplasma-like organism (MLO) were characterized in the scallop Argopecten irradians, and the first report of such infection in this scallop was represented.Ultrastructurally these microorganisms are usually pleomorphic and variable in morphology and size, and appear in several cell types such as small spherical body, rod-shaped bodies and longer filament-shaped body.They lack a cell wall.These observations revealed that these types of the prokaryote showed some characteristics of a mycoplasma-like organism (MLO).MLO reproduced in two ways:binary fission and budding.The results of isolation and purification showed that a large number of MLOs existed in the tissues of diseased scallops.The results of experimental infection revealed that the MLO is pathogenic to the scallop Argopecten irradians.
Intracytoplasmic infection with a prokaryotic mycoplasma-like organism (MLO) were characterized in the scallop Argopecten irradians, and the first report of such infection in this scallop was represented.Ultrastructurally these microorganisms are usually pleomorphic and variable in morphology and size, and appear in several cell types such as small spherical body, rod-shaped bodies and longer filament-shaped body.They lack a cell wall.These observations revealed that these types of the prokaryote showed some characteristics of a mycoplasma-like organism (MLO).MLO reproduced in two ways:binary fission and budding.The results of isolation and purification showed that a large number of MLOs existed in the tissues of diseased scallops.The results of experimental infection revealed that the MLO is pathogenic to the scallop Argopecten irradians.
