2010 Vol. 32, No. 3
Display Method:
2010, 32(3): 1-7.
Abstract:
During processing the shipboard ADCP data of the winter cruise off the Zhujiang River mouth in 2006, it is found that Joyce’s method cannot correct the systematic error in the data effectively, which is because that the misalignment angle is variable and is related to the vessel speed and heading. A cosine fitting function of heading is proposed for the misalignment angle, and by which the data systematic error is then corrected well.The current errors in the processed data are estimated via the special software VmDas, and a approach to determining the existence of the systematic errors is given. It is found that there are some incorrect measurements and they cannot be identified as bad data by VmDas, the influence of sea state on the data quality is analyzed, and finally puts forward a procedure for the data quality control and systematic error correction are put forward.
During processing the shipboard ADCP data of the winter cruise off the Zhujiang River mouth in 2006, it is found that Joyce’s method cannot correct the systematic error in the data effectively, which is because that the misalignment angle is variable and is related to the vessel speed and heading. A cosine fitting function of heading is proposed for the misalignment angle, and by which the data systematic error is then corrected well.The current errors in the processed data are estimated via the special software VmDas, and a approach to determining the existence of the systematic errors is given. It is found that there are some incorrect measurements and they cannot be identified as bad data by VmDas, the influence of sea state on the data quality is analyzed, and finally puts forward a procedure for the data quality control and systematic error correction are put forward.
2010, 32(3): 8-13.
Abstract:
A convection term in the Navier-Stokes equations plays a important role to generate recirculation. The comparative experiment of numerical methods applied to the convection term are carried out to simulate the tidal flow in the Xiamen Bay. Results of the numerical experiment are compared with results from the physical model. The influence of different numerical methods for convection term on the flow pattern results in the Xiamen Bay is evaluated and the best scheme is proposed.
A convection term in the Navier-Stokes equations plays a important role to generate recirculation. The comparative experiment of numerical methods applied to the convection term are carried out to simulate the tidal flow in the Xiamen Bay. Results of the numerical experiment are compared with results from the physical model. The influence of different numerical methods for convection term on the flow pattern results in the Xiamen Bay is evaluated and the best scheme is proposed.
2010, 32(3): 14-22.
Abstract:
The principles, methods and observation system of ocean acoustic tomography are analyzed and discussed. On the methods used in ocean acoustic tomography, mainly six methods are discussed and compared, especially ray travel time tomography, are generalized. The inverse problem and error analysis of the ocean acoustic tomography also are discussed in detail. At the same time, the design technologies of the observation system were introduced.
The principles, methods and observation system of ocean acoustic tomography are analyzed and discussed. On the methods used in ocean acoustic tomography, mainly six methods are discussed and compared, especially ray travel time tomography, are generalized. The inverse problem and error analysis of the ocean acoustic tomography also are discussed in detail. At the same time, the design technologies of the observation system were introduced.
The distribution of hydrocarbons in the surface sediments from the Huanghe Estuary and adjacent area
2010, 32(3): 23-30.
Abstract:
The surface sediment samples from the Huanghe Estuary were collected in September 2003 to explore the distribution and transportation of hydrocarbons in organic matter. The total concentrations of alkanes and polycyclic hydrocarbons varied from 0.38~2.55 to 0.371 ~0.650 μg/g, respectively. Significant differences were observed between the northern section and the southern section.Owing to the influence of the oilfield near the Huanghe Delta, the levels of two kinds of hydrocarbons show the highest level at the mouth in the northern section.Owing to the influence of the water from the Huanghe River, the hydrocarbons increase with the increasing of the distance from the coast in the southern section because the larger size particles are easy to deposit at the mouth of the river and the smaller particles resided with more hydrocarbons are easy to transport over long distance. More biogenic n-alkanes were found in the northern section than that in the southern section. The farther away from the river, the less terrestrial organic matter was observed in the southern section. The PAHs mainly were originated from coal burning in the southern section, and PAH inputs could come from petroleum and coal burning in the northern section.
The surface sediment samples from the Huanghe Estuary were collected in September 2003 to explore the distribution and transportation of hydrocarbons in organic matter. The total concentrations of alkanes and polycyclic hydrocarbons varied from 0.38~2.55 to 0.371 ~0.650 μg/g, respectively. Significant differences were observed between the northern section and the southern section.Owing to the influence of the oilfield near the Huanghe Delta, the levels of two kinds of hydrocarbons show the highest level at the mouth in the northern section.Owing to the influence of the water from the Huanghe River, the hydrocarbons increase with the increasing of the distance from the coast in the southern section because the larger size particles are easy to deposit at the mouth of the river and the smaller particles resided with more hydrocarbons are easy to transport over long distance. More biogenic n-alkanes were found in the northern section than that in the southern section. The farther away from the river, the less terrestrial organic matter was observed in the southern section. The PAHs mainly were originated from coal burning in the southern section, and PAH inputs could come from petroleum and coal burning in the northern section.
2010, 32(3): 31-39.
Abstract:
The concentrations of methane and sulfate in pore-water and pools of reduced sulfur compounds (acid volatile sulfur, pyrite and organic sulfur) and total organic carbon in sediment were determined at three sites (QA-11, QA-9 and QA-14) in the shore sediments of Qi’ao Island in the Zhujiang Estuary. By using a steady state diffusive model,sulfate reduction and anaerobic oxidation methane fluxes were calculated from pore-water sulfate and methane profiles. The sulfate reduction flux equaled 1.74 and 1.14 mmol/(m2·d) at Sites QA-9 and QA-14, and the methane anaerobic flux equaled 0.34 and 0.29 mmol/(m2(d) respectively.Because the sulfate supply from overlying water is limited in intertidal sediment, the depth of sulfate reduction zone is shallow at Site QA-11. With the increasing of the distance from the coast and the seawater depth, the sulfate reduction flux gradually decreased from Sites QA-9 to QA-14 located in the subtidal zone, sulfate reduction might be controlled by the supply of organic matter in sediment, meanwhile the contribution of the anaerohic oxidation of methane to the sulfate reduction increased from 19.2% to 25.5％. The results show that according to the order of high to low content of reduced sulfur of different forms in sediment they are organic sulfur,pyrite,acid volatile sulfur. The concentration of AVS and the sulfate reduction flux showed obvious correlation in the sedimentary cores of three sites. The values of the sulfur content ratio of pyrite to AVS were 7.9 and 3.6 at Sites QA-11 and QA-14 respectively, suggesting that AVS could be transformed to pyrite efficiently and the sulfate reduction was likely to limit formation of pyrite in the sediments, and the sulfur content ratio of pyrite to AVS being less than 3, with value of 2.2, at Site QA-9 indicated that sulfide mineralization was limited by the availability of highly reactive iron.
The concentrations of methane and sulfate in pore-water and pools of reduced sulfur compounds (acid volatile sulfur, pyrite and organic sulfur) and total organic carbon in sediment were determined at three sites (QA-11, QA-9 and QA-14) in the shore sediments of Qi’ao Island in the Zhujiang Estuary. By using a steady state diffusive model,sulfate reduction and anaerobic oxidation methane fluxes were calculated from pore-water sulfate and methane profiles. The sulfate reduction flux equaled 1.74 and 1.14 mmol/(m2·d) at Sites QA-9 and QA-14, and the methane anaerobic flux equaled 0.34 and 0.29 mmol/(m2(d) respectively.Because the sulfate supply from overlying water is limited in intertidal sediment, the depth of sulfate reduction zone is shallow at Site QA-11. With the increasing of the distance from the coast and the seawater depth, the sulfate reduction flux gradually decreased from Sites QA-9 to QA-14 located in the subtidal zone, sulfate reduction might be controlled by the supply of organic matter in sediment, meanwhile the contribution of the anaerohic oxidation of methane to the sulfate reduction increased from 19.2% to 25.5％. The results show that according to the order of high to low content of reduced sulfur of different forms in sediment they are organic sulfur,pyrite,acid volatile sulfur. The concentration of AVS and the sulfate reduction flux showed obvious correlation in the sedimentary cores of three sites. The values of the sulfur content ratio of pyrite to AVS were 7.9 and 3.6 at Sites QA-11 and QA-14 respectively, suggesting that AVS could be transformed to pyrite efficiently and the sulfate reduction was likely to limit formation of pyrite in the sediments, and the sulfur content ratio of pyrite to AVS being less than 3, with value of 2.2, at Site QA-9 indicated that sulfide mineralization was limited by the availability of highly reactive iron.
2010, 32(3): 40-50.
Abstract:
The sea surface temperature (SST) was estimated by the record of long-chain alkenone unsaturation index in the Sanmen Bay sediment. The calculated result shows that SST fluctuation ranges from 15.97 to 18.00 ℃,and average is 17.03 ℃. The calculated value is lower than the annual measured value 3.52 ℃ in the same year. At one time, the stratigraphic record history of El Nio in the Sanmen Bay sediment was reescablished using the relatimship of long-chain alkenone unsaturation index with SST.The research indicates that change of climate event of large scale in the Sanmen Bay is same to that of the Pacific Ocean, both are major influenced by the climate factor. The event corresponds with each other in form and age, but its range of fluctuation is inferior to the Pacific Ocean because of the effect of location and monsoon. A series of characteristics of macrobenthos including the signal of community structure change, biomass, density of inhabit and biodiversity was compared both in the periods of El Nio and non-El Nio. The research indicates that zooplankton species, the biomass and the abundance have the high tendency in the period of El Nio. That was because the intensity of the warm current invasion increased, and warm-water zooplankton was carried into the Samen Bay.
The sea surface temperature (SST) was estimated by the record of long-chain alkenone unsaturation index in the Sanmen Bay sediment. The calculated result shows that SST fluctuation ranges from 15.97 to 18.00 ℃,and average is 17.03 ℃. The calculated value is lower than the annual measured value 3.52 ℃ in the same year. At one time, the stratigraphic record history of El Nio in the Sanmen Bay sediment was reescablished using the relatimship of long-chain alkenone unsaturation index with SST.The research indicates that change of climate event of large scale in the Sanmen Bay is same to that of the Pacific Ocean, both are major influenced by the climate factor. The event corresponds with each other in form and age, but its range of fluctuation is inferior to the Pacific Ocean because of the effect of location and monsoon. A series of characteristics of macrobenthos including the signal of community structure change, biomass, density of inhabit and biodiversity was compared both in the periods of El Nio and non-El Nio. The research indicates that zooplankton species, the biomass and the abundance have the high tendency in the period of El Nio. That was because the intensity of the warm current invasion increased, and warm-water zooplankton was carried into the Samen Bay.
2010, 32(3): 51-59.
Abstract:
Surface and core sediment samples were collected during cruises in the East China Sea and the Huanghai Sea in April and October of 2006 to study the spatial distributions of biogenic silicon (BSi) in sediments and to evaluate its potential for productivity reconstructions. The results show that the BSi content of surface sediments is 0.018%~2.516%, averaging 0.726%.The vertical distribution profiles reveal that the BSi content is relatively stable, in accordance with the variations of the contemporary living phytoplankton biomass.A linear regression analysis method was adopted to prove that the BSi content has a positive relationship with the living phytoplankton biomass. To further confirm the applicability and credibility of the reconstruction potential of BSi, the method of Tunnicliffe et al.was used to study the stability of BSi in sediments. The survey indicates that there is almost no degradation of BSi in sediments over the past 150 a.Therefore, it is concluded that BSi in sediments may be used as an index to reconstruct paleoproductivity fluctuations.
Surface and core sediment samples were collected during cruises in the East China Sea and the Huanghai Sea in April and October of 2006 to study the spatial distributions of biogenic silicon (BSi) in sediments and to evaluate its potential for productivity reconstructions. The results show that the BSi content of surface sediments is 0.018%~2.516%, averaging 0.726%.The vertical distribution profiles reveal that the BSi content is relatively stable, in accordance with the variations of the contemporary living phytoplankton biomass.A linear regression analysis method was adopted to prove that the BSi content has a positive relationship with the living phytoplankton biomass. To further confirm the applicability and credibility of the reconstruction potential of BSi, the method of Tunnicliffe et al.was used to study the stability of BSi in sediments. The survey indicates that there is almost no degradation of BSi in sediments over the past 150 a.Therefore, it is concluded that BSi in sediments may be used as an index to reconstruct paleoproductivity fluctuations.
2010, 32(3): 60-66.
Abstract:
The Magellan seamount trail includes tens of isolated guyots trending EW.A backtracking method and a hot-spotting method were used to trace the Magellan seamount trail from the movement of a plate and its geometry based on previous studies in this region. The result shows that the Magellan seamount trail is the collective products of intraplate volcanism originating from multiple hot spots and plate tectogenesis. The Magellan seamount trail is derived from the present French Polynesian hot spots trending NNW during the Cretaceous. They are also affected by the activity of two fracture zones, which trend SN and NNW, and thermal activity with the movement of the plate. Finally the present Magellan seamount trail is formed.
The Magellan seamount trail includes tens of isolated guyots trending EW.A backtracking method and a hot-spotting method were used to trace the Magellan seamount trail from the movement of a plate and its geometry based on previous studies in this region. The result shows that the Magellan seamount trail is the collective products of intraplate volcanism originating from multiple hot spots and plate tectogenesis. The Magellan seamount trail is derived from the present French Polynesian hot spots trending NNW during the Cretaceous. They are also affected by the activity of two fracture zones, which trend SN and NNW, and thermal activity with the movement of the plate. Finally the present Magellan seamount trail is formed.
2010, 32(3): 67-78.
Abstract:
Sediment samples collected from the eastern Beibu Gulf were analyzed in the laboratory to obtain grain-size distributions and mineral components. Four main control factors are obtained using a factor analysis. Factor 1 is contributed by 2.5Φ-3.75Φ and 5.75Φ-7.75Φ. Factor 2 respects fine suspended load component, indicating that the provenance contribution from the Qiongzhou Strait and the high score area is consistent with the weak circulation. Factor 3 is a indicator of terrigenous coarse bedload component from the west and northwest coast of the Beibu Gulf. Factor 4 can reflect the transportation by the coastal current along the east coast off Hainan Island and the west of Guangdong Province. The study area can be separated into four subareas of the sediment sources on the basis of heavy mineral analysis. A grain-size trend analysis model is separately used for the four subareas to estimate the net sediment transport pathways, which can remove the affects induced by the sediment mixing from different sources. A converge center of grain-size trend vectors in the area of the west of Hainan Island might result from the mixing of different sources of sediments, instead of sediment transport. Actually, the northward transport dominates this area of the west of Hainan Island. Another converge center in the northern area is well agreement with the local geomorphology and large-scale ocean circulation pattern. Thus, the application of grain-size trend should consider the effect of sediment sources and spatial scales in order to derive the reasonable net sediment transport pathways.
Sediment samples collected from the eastern Beibu Gulf were analyzed in the laboratory to obtain grain-size distributions and mineral components. Four main control factors are obtained using a factor analysis. Factor 1 is contributed by 2.5Φ-3.75Φ and 5.75Φ-7.75Φ. Factor 2 respects fine suspended load component, indicating that the provenance contribution from the Qiongzhou Strait and the high score area is consistent with the weak circulation. Factor 3 is a indicator of terrigenous coarse bedload component from the west and northwest coast of the Beibu Gulf. Factor 4 can reflect the transportation by the coastal current along the east coast off Hainan Island and the west of Guangdong Province. The study area can be separated into four subareas of the sediment sources on the basis of heavy mineral analysis. A grain-size trend analysis model is separately used for the four subareas to estimate the net sediment transport pathways, which can remove the affects induced by the sediment mixing from different sources. A converge center of grain-size trend vectors in the area of the west of Hainan Island might result from the mixing of different sources of sediments, instead of sediment transport. Actually, the northward transport dominates this area of the west of Hainan Island. Another converge center in the northern area is well agreement with the local geomorphology and large-scale ocean circulation pattern. Thus, the application of grain-size trend should consider the effect of sediment sources and spatial scales in order to derive the reasonable net sediment transport pathways.
2010, 32(3): 79-87.
Abstract:
On the basis of 372 images of Spot/Vegetation from 1998 to 2008, the Mann-Kendall non-parametric trend test method was used to analyze the normalized difference vegetation in dex(NDVI) trends on the Jiaodong Penisula.During past decade, the areas with decreasing NDVI trends dominated the Jiaodong Peninsula. About 19.3% of the whole area exhibited significant declining trends in the NDVI, and merely 2.8% of areas showed increasing trends. The areas with decreasing trends distributed annularly along the coastline. The increasing trends gradually became more prominent from the coastline to the inner land. Most regions which manifested distinct weakening trends were mainly located within a distance of 30 km apart from the coastline. The regions showing obvious improvement were located in the central peninsula and the coastal forest shelterbelt areas. Human activity and its spatial distribution were the main causes of NDVI changes. Urbanization, industrialization and exploitation of the coastal wetlands resulted in the decaying of NDVI. Protection of the mountain vegetation and the construction of the coastal forest shelterbelt promoted the increasing of NDVI.
On the basis of 372 images of Spot/Vegetation from 1998 to 2008, the Mann-Kendall non-parametric trend test method was used to analyze the normalized difference vegetation in dex(NDVI) trends on the Jiaodong Penisula.During past decade, the areas with decreasing NDVI trends dominated the Jiaodong Peninsula. About 19.3% of the whole area exhibited significant declining trends in the NDVI, and merely 2.8% of areas showed increasing trends. The areas with decreasing trends distributed annularly along the coastline. The increasing trends gradually became more prominent from the coastline to the inner land. Most regions which manifested distinct weakening trends were mainly located within a distance of 30 km apart from the coastline. The regions showing obvious improvement were located in the central peninsula and the coastal forest shelterbelt areas. Human activity and its spatial distribution were the main causes of NDVI changes. Urbanization, industrialization and exploitation of the coastal wetlands resulted in the decaying of NDVI. Protection of the mountain vegetation and the construction of the coastal forest shelterbelt promoted the increasing of NDVI.
2010, 32(3): 88-94.
Abstract:
A novel self-contained in situ sediment acoustic measurement system based on hydraulic driving penetration and its application in the middle area of the southern Huanghai Sea are introduced in detail. The system was designed for the in situ measurement of sound speeds and attenuation coefficients of seafloor sediments. By using a hydraulic driving device, the system drives four acoustic probes into sediments at an even speed, and this decreases disturbances to sediments introduced by the penetration of acoustic probes. It can work full-automatically on the seafloor without real-time control, and data are stored self-containedly into its storage unit. Its operating water depth and the measuring depth are 500 and 1.0 m respectively. The measuring frequency is 30 kHz, and the sampling rate of A/D converter is 10 MHz. A set of in situ sound speeds and attenuation coefficients of seafloor sediments were obtained at 40 stations in the middle area of the southern Huanghai Sea. The seawater sound speed measured by the in situ system was calibrated according to the seawater sound speed measured by a CTD profiler.The relative error is less than 0.5%. The result indicates that the data measured by the in situ sediment acoustic system are accurate and credible.
A novel self-contained in situ sediment acoustic measurement system based on hydraulic driving penetration and its application in the middle area of the southern Huanghai Sea are introduced in detail. The system was designed for the in situ measurement of sound speeds and attenuation coefficients of seafloor sediments. By using a hydraulic driving device, the system drives four acoustic probes into sediments at an even speed, and this decreases disturbances to sediments introduced by the penetration of acoustic probes. It can work full-automatically on the seafloor without real-time control, and data are stored self-containedly into its storage unit. Its operating water depth and the measuring depth are 500 and 1.0 m respectively. The measuring frequency is 30 kHz, and the sampling rate of A/D converter is 10 MHz. A set of in situ sound speeds and attenuation coefficients of seafloor sediments were obtained at 40 stations in the middle area of the southern Huanghai Sea. The seawater sound speed measured by the in situ system was calibrated according to the seawater sound speed measured by a CTD profiler.The relative error is less than 0.5%. The result indicates that the data measured by the in situ sediment acoustic system are accurate and credible.
2010, 32(3): 95-106.
Abstract:
Based on the bottom trawl surveys in four seasons from 2006 to 2007,the temporal and spatial distribution of Miichthys miiuy resources was explored in the area inside bottom-trawl fishing forbidden zone line of Jiangsu sea area and the near zone. The results show that: (1) Miichthys miiuy is mainly distributed in the south of 34 00'N in Jiangsu sea area,and its main spawning area is located in the radiating sand ridges and the surrounding coastal waters during the spring spawning period; (2) the southern central sea area in Jiangsu Province is the transitional feeding ground for Miichthys miiuy in early development stages, there is a gradually decreased tendency of the juvenile groups in the zone; (3) Miichthys miiuy is mainly distributed in Jiangsu sea area in spring, summer and autumn, while it is seldom distributed in winter; (4) seafloor topography and physiognomy, tidal and current type and radiating sand ridge are important factors influencing the regional ecology which should be concerned.
Based on the bottom trawl surveys in four seasons from 2006 to 2007,the temporal and spatial distribution of Miichthys miiuy resources was explored in the area inside bottom-trawl fishing forbidden zone line of Jiangsu sea area and the near zone. The results show that: (1) Miichthys miiuy is mainly distributed in the south of 34 00'N in Jiangsu sea area,and its main spawning area is located in the radiating sand ridges and the surrounding coastal waters during the spring spawning period; (2) the southern central sea area in Jiangsu Province is the transitional feeding ground for Miichthys miiuy in early development stages, there is a gradually decreased tendency of the juvenile groups in the zone; (3) Miichthys miiuy is mainly distributed in Jiangsu sea area in spring, summer and autumn, while it is seldom distributed in winter; (4) seafloor topography and physiognomy, tidal and current type and radiating sand ridge are important factors influencing the regional ecology which should be concerned.
2010, 32(3): 107-112.
Abstract:
Boleophthalmus pectinirostris is an amphibious economic fish wildly distributed in southeast coast of China. B. pectinirostris were peritoneally injected with 1
Boleophthalmus pectinirostris is an amphibious economic fish wildly distributed in southeast coast of China. B. pectinirostris were peritoneally injected with 1
2010, 32(3): 113-120.
Abstract:
Nutrition composition in muscle and air bladder of wild Bahaba flavolabiata was investigated. Results show that in the nutrition composition of muscle and air bladder there are high protein and low fat. In muscle, the composition of amino acids met the Food and Agriculture Organization of the Untied Nations/World Health Organization (FAO/ WHO) standard. The contents of amino acid,essential amino acid and flavour amino acid are relatively high with complete component type. In air bladder, the composition of amino acid is less than the FAO/ WHO standard, while its protein content of 35.90% was higher than that of other aquatic produces reported, and the contents of crude fat and crude ash are lower. The content of amino acid is high with complete component type, being rich in flavour amino acids. Four kinds of derived amino acids such as Tau,γ-GAba, Orn, and HYpro with important physiological functions were found in air bladder. The ratio of branch-chain amino acid to aromatic amino acid in muscle and air bladder was calculated closing the normal value of that in human. The contents of unsaturated fatty acids are relatively rich, with the ratio of 1.45 and 1.51 in terms of unsaturated fatty acids/saturated fatty acids separately. calcium,shodium,potassium magnesium,iron,copper and zinc were found which were essential for the human. The results indicate that muscle and air blader of B.flavolabiata are the high nutritive sea-food.
Nutrition composition in muscle and air bladder of wild Bahaba flavolabiata was investigated. Results show that in the nutrition composition of muscle and air bladder there are high protein and low fat. In muscle, the composition of amino acids met the Food and Agriculture Organization of the Untied Nations/World Health Organization (FAO/ WHO) standard. The contents of amino acid,essential amino acid and flavour amino acid are relatively high with complete component type. In air bladder, the composition of amino acid is less than the FAO/ WHO standard, while its protein content of 35.90% was higher than that of other aquatic produces reported, and the contents of crude fat and crude ash are lower. The content of amino acid is high with complete component type, being rich in flavour amino acids. Four kinds of derived amino acids such as Tau,γ-GAba, Orn, and HYpro with important physiological functions were found in air bladder. The ratio of branch-chain amino acid to aromatic amino acid in muscle and air bladder was calculated closing the normal value of that in human. The contents of unsaturated fatty acids are relatively rich, with the ratio of 1.45 and 1.51 in terms of unsaturated fatty acids/saturated fatty acids separately. calcium,shodium,potassium magnesium,iron,copper and zinc were found which were essential for the human. The results indicate that muscle and air blader of B.flavolabiata are the high nutritive sea-food.
2010, 32(3): 121-128.
Abstract:
EF-hand motif plays essential roles in the absorption and transportation of calcium ion in eukaryotic cells, and is possibly involved in the formation of shell and nacre in oysters. Degenerated primers were designed according to the conserved sequences of reported EF-hand proteins in oysters, and a novel gene PMMG1(Pinctada maxima mantle gene 1) was screened from the mantle cDNA library of P. maxima. The PMMG1 cDNA contained 618 nucleotides and encoded 140 amino acids (aa), including a putative signal peptide of 22 aa. PMMG1 protein shared an identity of 56％ with PFMG1 from P. fucata and had two putative EF-hand motifs. The cDNA fragment encoding mature protein of PMMG1 was cloned and integrated into prokaryotic expression vector pET32-a. A recombinant protein of expected size was induced by IPTG and then purified by Ni2+-NTA resin. Electrophoretic shift experiment revealed that the PMMG1 protein could bind both Ca2+ and Mg2+ ion, and the tissue-specific expression level of PMMG1 was much higher in mantle than in other tissues, which may be involved in the formation of calcite while binding Ca2+ or the formation of aragonite while binding Mg2+. This work can benefit the further investigation into the roles of EF-hand proteins in the biomineralization of pearl oysters.
EF-hand motif plays essential roles in the absorption and transportation of calcium ion in eukaryotic cells, and is possibly involved in the formation of shell and nacre in oysters. Degenerated primers were designed according to the conserved sequences of reported EF-hand proteins in oysters, and a novel gene PMMG1(Pinctada maxima mantle gene 1) was screened from the mantle cDNA library of P. maxima. The PMMG1 cDNA contained 618 nucleotides and encoded 140 amino acids (aa), including a putative signal peptide of 22 aa. PMMG1 protein shared an identity of 56％ with PFMG1 from P. fucata and had two putative EF-hand motifs. The cDNA fragment encoding mature protein of PMMG1 was cloned and integrated into prokaryotic expression vector pET32-a. A recombinant protein of expected size was induced by IPTG and then purified by Ni2+-NTA resin. Electrophoretic shift experiment revealed that the PMMG1 protein could bind both Ca2+ and Mg2+ ion, and the tissue-specific expression level of PMMG1 was much higher in mantle than in other tissues, which may be involved in the formation of calcite while binding Ca2+ or the formation of aragonite while binding Mg2+. This work can benefit the further investigation into the roles of EF-hand proteins in the biomineralization of pearl oysters.
2010, 32(3): 129-137.
Abstract:
The profile of diarrhetic shellfish poisoning (DSP) toxins in shellfish samples collected from Chinas coastal areas was analyzed with liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) analysis. The results of LC-MS/MS analysis show that Patinopecten yessoensis and Argopecten irradians collected from the northern Huanghai Sea contain YTX and 45-OH-homo-YTX. Furthermore, Homo-YTX, with very low levels (less than LOQ) was also detected in five shellfish species.This is the first report of the presence of yessotoxins (YTXs) in shellfish from Chinas coastal areas. YTXs are disulfated polyether marine toxins with a characteristic rapid death in the intraperitoneal mouse bioassay, but detailed information on the mechanism(s) of toxic action is not available. These results indicate that biotoxin contamination of shellfish in Chinas coastal areas are very complicated, it is very urgent to carry out researches in our country on toxin structures, biological origin(s), toxicological properties, ecological effects, distribution characteristics and maximum permitted levels.
The profile of diarrhetic shellfish poisoning (DSP) toxins in shellfish samples collected from Chinas coastal areas was analyzed with liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) analysis. The results of LC-MS/MS analysis show that Patinopecten yessoensis and Argopecten irradians collected from the northern Huanghai Sea contain YTX and 45-OH-homo-YTX. Furthermore, Homo-YTX, with very low levels (less than LOQ) was also detected in five shellfish species.This is the first report of the presence of yessotoxins (YTXs) in shellfish from Chinas coastal areas. YTXs are disulfated polyether marine toxins with a characteristic rapid death in the intraperitoneal mouse bioassay, but detailed information on the mechanism(s) of toxic action is not available. These results indicate that biotoxin contamination of shellfish in Chinas coastal areas are very complicated, it is very urgent to carry out researches in our country on toxin structures, biological origin(s), toxicological properties, ecological effects, distribution characteristics and maximum permitted levels.
2010, 32(3): 138-145.
Abstract:
Bathing beach is important to human health as receation ground. Rotavirus, astrovirus and poliovirus are typical gastroenteritis pathogenies, so the three typical enteric viruses in representative are investigated bathing beachs water. Twenty surface seawater samples were investigated from representative ten bathing beaches in August 2007. Viruses were concentrated by Millipore viruse concentration device(Centricon Plus-70).These viruses were detected by RT-PCR. Positived results of rotaviruses is 40%, astrovirus is 35％, polioviruses is 40％; in these ten representative bathing beaches, except that a virus-free is detected in the Beihai Sea, the rest have varying degrees of enteric virus positive,which shows that the focus of beach water quality has been suffered from enteric virus with various degrees of pollution. In order to avoid disease breaking-out from bad bathing beach seawater quality, sanitation management must be strengthened.
Bathing beach is important to human health as receation ground. Rotavirus, astrovirus and poliovirus are typical gastroenteritis pathogenies, so the three typical enteric viruses in representative are investigated bathing beachs water. Twenty surface seawater samples were investigated from representative ten bathing beaches in August 2007. Viruses were concentrated by Millipore viruse concentration device(Centricon Plus-70).These viruses were detected by RT-PCR. Positived results of rotaviruses is 40%, astrovirus is 35％, polioviruses is 40％; in these ten representative bathing beaches, except that a virus-free is detected in the Beihai Sea, the rest have varying degrees of enteric virus positive,which shows that the focus of beach water quality has been suffered from enteric virus with various degrees of pollution. In order to avoid disease breaking-out from bad bathing beach seawater quality, sanitation management must be strengthened.
2010, 32(3): 146-152.
Abstract:
The changes of primary photochemical reactions in Kappaphycus alvarezii exposed to low-salinity stress were studied by analyzing their transient chlorophyll a fluorescence dynamic curves. The results show that the main photochemical reaction of PSⅡ, its donor and acceptor sides vary widely in K. alvarezii while being exposed to low-salinity.Although many un-favored profiles like the fraction of PSⅡ centers closed, the storage capacity of plastoquinone (PQ), the frequency of QA reduced to QA and the absorption energy flux decreased meanwhile the dissipation energy at the level of the antenna chlorophylls increased when K. alvarezii was exposed to salinity of 28, however, the maximal photochemical efficiency of PSⅡ seemed no significantly change and the performance indexes even increased because of number of reversible photochemical regulations such as the increase in the density of reaction center of PSⅡ per excited cross-section of algal sample (RC/CS0 and RC/CSm), the energy flux of electrons from QA into the electron transport chain per RC(ET0/RC)and the energy flux per CS (ET0/CSm). While seawater salinity dropped to 22, the storage capacity of PQ and the frequency of QA reduced to QA in K. alvarezii significantly reduced, the electrons transferred to RC of PSⅠ were severely blocked. Therefore, both the light absorbed and trapped as well as the electron transported in K. alvarezii declined, and that the superfluous energy caused a plastic damage to its photosynthetic apparatus. When the salinity further fell to 18, both comprehensive performance indexes and the maximal photochemical efficiency of PSⅡin K. alvarezii distinctly declined due to a rapid decrease in active photosynthetic reaction centers and a heavy interdiction of electron transport flux. Therefore,death of K. alvarezii exposed to such low salinity happened inevitably.
The changes of primary photochemical reactions in Kappaphycus alvarezii exposed to low-salinity stress were studied by analyzing their transient chlorophyll a fluorescence dynamic curves. The results show that the main photochemical reaction of PSⅡ, its donor and acceptor sides vary widely in K. alvarezii while being exposed to low-salinity.Although many un-favored profiles like the fraction of PSⅡ centers closed, the storage capacity of plastoquinone (PQ), the frequency of QA reduced to QA and the absorption energy flux decreased meanwhile the dissipation energy at the level of the antenna chlorophylls increased when K. alvarezii was exposed to salinity of 28, however, the maximal photochemical efficiency of PSⅡ seemed no significantly change and the performance indexes even increased because of number of reversible photochemical regulations such as the increase in the density of reaction center of PSⅡ per excited cross-section of algal sample (RC/CS0 and RC/CSm), the energy flux of electrons from QA into the electron transport chain per RC(ET0/RC)and the energy flux per CS (ET0/CSm). While seawater salinity dropped to 22, the storage capacity of PQ and the frequency of QA reduced to QA in K. alvarezii significantly reduced, the electrons transferred to RC of PSⅠ were severely blocked. Therefore, both the light absorbed and trapped as well as the electron transported in K. alvarezii declined, and that the superfluous energy caused a plastic damage to its photosynthetic apparatus. When the salinity further fell to 18, both comprehensive performance indexes and the maximal photochemical efficiency of PSⅡin K. alvarezii distinctly declined due to a rapid decrease in active photosynthetic reaction centers and a heavy interdiction of electron transport flux. Therefore,death of K. alvarezii exposed to such low salinity happened inevitably.
2010, 32(3): 153-161.
Abstract:
The Changjiang Estuary deep-waterway project was started in 1998, and in 2002 and 2005, the first and second phase projects have been completed one after another, the water depth of navigation reached 8.5 and 10.0 m respectively. Since the third phase project in 2006, the middle segments of the North Passage have been silted for successive four years and the average annual dredging maintenance volume has reached 60×106 m3, which has affected the target of the third phase project. Using a special self-developed digital elevation model platform for quantitative analysis and establishing a time series and spatial attribute database, the rule of riverbed erosion and deposition variation and project results were analyzed quantitatively. The analysis results reveal silted sediment sources, silted process, key siltation causes and silted positions for the North Passage deep waterway of Changjiang Estuary South Channel, which provide the scientific basis for the engineering decision-making.
The Changjiang Estuary deep-waterway project was started in 1998, and in 2002 and 2005, the first and second phase projects have been completed one after another, the water depth of navigation reached 8.5 and 10.0 m respectively. Since the third phase project in 2006, the middle segments of the North Passage have been silted for successive four years and the average annual dredging maintenance volume has reached 60×106 m3, which has affected the target of the third phase project. Using a special self-developed digital elevation model platform for quantitative analysis and establishing a time series and spatial attribute database, the rule of riverbed erosion and deposition variation and project results were analyzed quantitatively. The analysis results reveal silted sediment sources, silted process, key siltation causes and silted positions for the North Passage deep waterway of Changjiang Estuary South Channel, which provide the scientific basis for the engineering decision-making.
2010, 32(3): 162-166.
Abstract:
Sloping artificial islands are mostly applied to the oil platforms in shoal areas.It is the slopes that have an effect of ice-load reduction relative to vertical structures.However,ice damage will inevitably occur when the ice climbs up the slopes.It is necessary to study the main parameters of the sea-ice climbing slope and pile-up. Laboratory model tests are conducted to simulate the process of the sea-ice climbing slope and pile-up by laying a concrete structure in the ice movement direction. The climbing angle,the sliding angle, the break length of sea-ice sheets and the maximum height of climbing slope, and the correlation between the break length and the elastic modulus were discussed. The results indicate that the higher water level, the easier of the ice climbing slope and pile-up occurs. The climbing angle and the sliding angle form after the pile consists of broken ice pieces in front of the structure. With the increase of the pile height, the climbing angle changes from a lower level to an upper; the sliding angle is the opposite, from an upper level to a lower. When the pile height grows up to an appropriate height, the height cannot rise with the moving ice. Instead, a new pile on the sloping slope of the old pile appears which provides a new idea for ice-load reduction in shallow waters.
Sloping artificial islands are mostly applied to the oil platforms in shoal areas.It is the slopes that have an effect of ice-load reduction relative to vertical structures.However,ice damage will inevitably occur when the ice climbs up the slopes.It is necessary to study the main parameters of the sea-ice climbing slope and pile-up. Laboratory model tests are conducted to simulate the process of the sea-ice climbing slope and pile-up by laying a concrete structure in the ice movement direction. The climbing angle,the sliding angle, the break length of sea-ice sheets and the maximum height of climbing slope, and the correlation between the break length and the elastic modulus were discussed. The results indicate that the higher water level, the easier of the ice climbing slope and pile-up occurs. The climbing angle and the sliding angle form after the pile consists of broken ice pieces in front of the structure. With the increase of the pile height, the climbing angle changes from a lower level to an upper; the sliding angle is the opposite, from an upper level to a lower. When the pile height grows up to an appropriate height, the height cannot rise with the moving ice. Instead, a new pile on the sloping slope of the old pile appears which provides a new idea for ice-load reduction in shallow waters.
2010, 32(3): 167-175.
Abstract:
Email alert
RSS