2008 Vol. 30, No. 5
Display Method:
2008, 30(5): 1-8.
Abstract:
The recent study achievementaboutthe Ryukyu Current(RC)is reviewed.It is pointed outthat the RC is animportant western boundary current in the North Pacific.The RC is strongly influenced by the mesoscale eddy and its velocity and volume transportex hibits subsurface maximum structure.The RC remarkably develops between the Okinawa and Amami-Ohshima Islands.The following three points need to betteraddress:(1)the origin of the RC,the formation mechanism and its temporal and spatial variations;(2)dynamic processes offormation and maintaining of the subsurface maximum structure,the development of RC from the northern of the Okinawa Island,and(3)the contributions of volume and heat transport to the Kuroshio.
The recent study achievementaboutthe Ryukyu Current(RC)is reviewed.It is pointed outthat the RC is animportant western boundary current in the North Pacific.The RC is strongly influenced by the mesoscale eddy and its velocity and volume transportex hibits subsurface maximum structure.The RC remarkably develops between the Okinawa and Amami-Ohshima Islands.The following three points need to betteraddress:(1)the origin of the RC,the formation mechanism and its temporal and spatial variations;(2)dynamic processes offormation and maintaining of the subsurface maximum structure,the development of RC from the northern of the Okinawa Island,and(3)the contributions of volume and heat transport to the Kuroshio.
2008, 30(5): 9-16.
Abstract:
The Pacific sea temperature from 1960-1999 was simulated using non-Boussinesq POP model, air temperature and wind stress in 1 000 hPa from NCEP.Compared to the observation,the results are rescannable and interesting.The importantresults as follows:The strongest warming is in equatorial center Pacific surface(Niño1 to Niño4).The strongest coolingis in middle-latitude center Pacific surface. There are warmin the north hemisphere Pacific coastunless about 40°N.The temperature increasingis biggerin east Pacific coastthan that in west Pacific coast.Most of Pacific Ocean temperature is decreased from 0 to 483 m with the depth,butthe equatorial center Pacific temperature is increased in sea surface and decreased in about-169 m and increased in 483 m.The temperature in the depth section of tropical center-western Pacific Oceanis decreased with time although El Niño events increasing since 1990.
The Pacific sea temperature from 1960-1999 was simulated using non-Boussinesq POP model, air temperature and wind stress in 1 000 hPa from NCEP.Compared to the observation,the results are rescannable and interesting.The importantresults as follows:The strongest warming is in equatorial center Pacific surface(Niño1 to Niño4).The strongest coolingis in middle-latitude center Pacific surface. There are warmin the north hemisphere Pacific coastunless about 40°N.The temperature increasingis biggerin east Pacific coastthan that in west Pacific coast.Most of Pacific Ocean temperature is decreased from 0 to 483 m with the depth,butthe equatorial center Pacific temperature is increased in sea surface and decreased in about-169 m and increased in 483 m.The temperature in the depth section of tropical center-western Pacific Oceanis decreased with time although El Niño events increasing since 1990.
2008, 30(5): 17-22.
Abstract:
The acoustic inversion equationis basic in acoustic measurement of physical parameters of sediments. Two kinds of acoustic inversion models of physical parameters based on acoustic theory and statistical theory are studied. Acoustic and physical measurement values in seabed sediments of the South China Sea shelfare applied to testingand comparing the two models. By instancing the physical parameters of porosity and water content,the inversion model based on double-parameterem pirical equationis well applicable but to be improved ininversion precision. The inversion model inferred by acoustic theory is maturatingininversing physical parameters of seabed sediments in the South China Sea.
The acoustic inversion equationis basic in acoustic measurement of physical parameters of sediments. Two kinds of acoustic inversion models of physical parameters based on acoustic theory and statistical theory are studied. Acoustic and physical measurement values in seabed sediments of the South China Sea shelfare applied to testingand comparing the two models. By instancing the physical parameters of porosity and water content,the inversion model based on double-parameterem pirical equationis well applicable but to be improved ininversion precision. The inversion model inferred by acoustic theory is maturatingininversing physical parameters of seabed sediments in the South China Sea.
2008, 30(5): 23-28.
Abstract:
The geophysical model function(GMF)describes the relationship between backscatteringand sea surface wind,so that wind vectors can be retrieved from backscattering measurement. The GMF plays animportantrole in ocean wind vectorretrievals,its performance will directly influence the accuracy of the retrieved wind vector. Neural network(NN)approach is used to develop a unified GMF for C-band and Ku-band(NN-GMF).Empirical GMF CMOD4 and QSCAT-1 are used to generate the simulated training data-set,and Gaussian noise ata signal noise ratio of 30 dB is added to the data-set to simulate the noise in the backscattering measurement. The NN-GMF employs radio frequency as an additional parameter,so it can be applied for both C-band and Ku-band. A nalysis shows that the normalized backscattering coefficient predicted by the NN-GMF is comparable with the normalized backscattering coefficient predicted by CMOD4 and QSCAT-1. Also the wind vectors retrieved from the NN-GMF and empirical GMF CMOD4 and Qscat-1 are comparable,indicating that the NN-GMF is as effective as the empirical GMF,and has the advantages of the universal form.
The geophysical model function(GMF)describes the relationship between backscatteringand sea surface wind,so that wind vectors can be retrieved from backscattering measurement. The GMF plays animportantrole in ocean wind vectorretrievals,its performance will directly influence the accuracy of the retrieved wind vector. Neural network(NN)approach is used to develop a unified GMF for C-band and Ku-band(NN-GMF).Empirical GMF CMOD4 and QSCAT-1 are used to generate the simulated training data-set,and Gaussian noise ata signal noise ratio of 30 dB is added to the data-set to simulate the noise in the backscattering measurement. The NN-GMF employs radio frequency as an additional parameter,so it can be applied for both C-band and Ku-band. A nalysis shows that the normalized backscattering coefficient predicted by the NN-GMF is comparable with the normalized backscattering coefficient predicted by CMOD4 and QSCAT-1. Also the wind vectors retrieved from the NN-GMF and empirical GMF CMOD4 and Qscat-1 are comparable,indicating that the NN-GMF is as effective as the empirical GMF,and has the advantages of the universal form.
2008, 30(5): 29-34.
Abstract:
Remote sensing(RS)based soil moisture reversionis original and tentative fortopographical survey and analysis in exposed tidal flat where this area is strongly affected by tidal fluctuation. The spatial distribution of soil water content is also highly helpful fordeep level cognition and comprehension of the ecological environmentthere. So takingexperiences from land phase soil property research,a soil moisture reversion model was established based on the correlation analysis betweenin situ soil water contentand its relevant RS spectrum data using Landsat ETM+image in anintertidal flatarea near Wanggang Port,Jiangsu Province,China. And then the model was applied for soil moisture reversion with good precision. Results showed that:(1)spectral reflectance of ETM+Band 4 has the maximum correlation with soil moisture in tidal flat;and(2)compared with different models such as multivariate linear model, single band,band-ratio and pseudo-NDVI model,single band model has the minimumerror forsoil mois-ture reversion. It was indicated that the distribution of soil water content in the exposed intertidal flat could be quickly and conveniently obtained by the model when the appropriate RS image was available.
Remote sensing(RS)based soil moisture reversionis original and tentative fortopographical survey and analysis in exposed tidal flat where this area is strongly affected by tidal fluctuation. The spatial distribution of soil water content is also highly helpful fordeep level cognition and comprehension of the ecological environmentthere. So takingexperiences from land phase soil property research,a soil moisture reversion model was established based on the correlation analysis betweenin situ soil water contentand its relevant RS spectrum data using Landsat ETM+image in anintertidal flatarea near Wanggang Port,Jiangsu Province,China. And then the model was applied for soil moisture reversion with good precision. Results showed that:(1)spectral reflectance of ETM+Band 4 has the maximum correlation with soil moisture in tidal flat;and(2)compared with different models such as multivariate linear model, single band,band-ratio and pseudo-NDVI model,single band model has the minimumerror forsoil mois-ture reversion. It was indicated that the distribution of soil water content in the exposed intertidal flat could be quickly and conveniently obtained by the model when the appropriate RS image was available.
2008, 30(5): 35-42.
Abstract:
Elemental,stable carboniso topic and lignin analyses were carried out to study the sources of surface sedimentary or ganic matterin the adjacentarea of the Changjiang Estuary.Ratios of carbonis nitrcyen content vary from 6.2 to 7.7,corresponding with bulk δ13C values of -19.9×10-3~-22.4×10-3. The content sum of vanillyl,syringyl and cinnamyl phenols produced from the oxidation of 100 mg or ganic carbonis between 0.15×10-2 and 1.56×10-2 mg/mgin shelf sediments,comparing with a value of 2.50×10-2 mg/mg in the mouth of the Changjiang Estuary.Averaged at 0.90,high values of(Ad/Al)v suggest that the terrigenous organic matter in the shelf is highly degraded.S/V(0.78±0.35)and C/V (0.13±0.08)ratios further indicate that these terrigenous organic matter originate from a mixture of woody and nonwoody angiosperm plants.Lignins in the southern shelf have a higher degree of degradation and more contribution from nonwoody angiosperm sources,which deposits along the coastline with a significant off shore decreasing trend.The distribution of lignin in the north is more homogenous due to the different hydrodynamic conditions.End-member calculations suggest that terrigenous organic matter can represent approximately 5% to 57% of total organic matterin various samples with a distinct off shore decreasing trend.Soil-derived terrestrial organic matter may account to majority compositionin most samples.
Elemental,stable carboniso topic and lignin analyses were carried out to study the sources of surface sedimentary or ganic matterin the adjacentarea of the Changjiang Estuary.Ratios of carbonis nitrcyen content vary from 6.2 to 7.7,corresponding with bulk δ13C values of -19.9×10-3~-22.4×10-3. The content sum of vanillyl,syringyl and cinnamyl phenols produced from the oxidation of 100 mg or ganic carbonis between 0.15×10-2 and 1.56×10-2 mg/mgin shelf sediments,comparing with a value of 2.50×10-2 mg/mg in the mouth of the Changjiang Estuary.Averaged at 0.90,high values of(Ad/Al)v suggest that the terrigenous organic matter in the shelf is highly degraded.S/V(0.78±0.35)and C/V (0.13±0.08)ratios further indicate that these terrigenous organic matter originate from a mixture of woody and nonwoody angiosperm plants.Lignins in the southern shelf have a higher degree of degradation and more contribution from nonwoody angiosperm sources,which deposits along the coastline with a significant off shore decreasing trend.The distribution of lignin in the north is more homogenous due to the different hydrodynamic conditions.End-member calculations suggest that terrigenous organic matter can represent approximately 5% to 57% of total organic matterin various samples with a distinct off shore decreasing trend.Soil-derived terrestrial organic matter may account to majority compositionin most samples.
2008, 30(5): 43-51.
Abstract:
Under standing the chemical and isotopic alteration of organic matter duringearly diagenesis is crucial to the studies of biogeochemical processes in marine and lacustrine environments.The isotopic composition(δ13C and δ15N),total organic carbon(TOC)and total nitrogen(TN)contents of sediment cores as well as plankton and suspended particulates from the coastal area off shore the Zhujiang Estuary were determined,and the fractional carbon content of total hydrolysable amino acids(THAA),total carbo hydrates(TCHO),total lipid and acid-insoluble organic compounds(AIOC)and their respective δ13C were analyzed,based on which,the magnitude and mechanismof chemical and isotopic fractionation of organic matter were investigated.Results showed that the degradable fractions of THAA、TCHO and lipid decreased from plankt on to POM to surface sediments and to the buried sediments,and δ13C of TOC and organic fractions kept stable with depth,but differed distinctly among the four fractions.The different degradation rates oforganic compounds and the formation and degradation of bacteria organic matterare the major mechanisms causing the chemical and isotopic alteration oforganic matter duringearly diagenesis1 Because of the lower carbohydrate content in the plankton and the rapid degradation of lipid,the carbon isotopic fractionation caused by selective degradation of compounds could be relatively small and was partially canceled by the addition of bacterial synthesized organic matter,resultingin the observed conservative nature of δ13C duringearly diagenesis.On the other hand,the addition of bacteria organic matter may account for the depletion and variation of δ15N caused by early diagenesis.The above studies suggested that δ13C can be a reliable proxy to the sources of organic matter,but δ15N cannot be used to indicate the origin of sedimented o rganic matterin the study area.
Under standing the chemical and isotopic alteration of organic matter duringearly diagenesis is crucial to the studies of biogeochemical processes in marine and lacustrine environments.The isotopic composition(δ13C and δ15N),total organic carbon(TOC)and total nitrogen(TN)contents of sediment cores as well as plankton and suspended particulates from the coastal area off shore the Zhujiang Estuary were determined,and the fractional carbon content of total hydrolysable amino acids(THAA),total carbo hydrates(TCHO),total lipid and acid-insoluble organic compounds(AIOC)and their respective δ13C were analyzed,based on which,the magnitude and mechanismof chemical and isotopic fractionation of organic matter were investigated.Results showed that the degradable fractions of THAA、TCHO and lipid decreased from plankt on to POM to surface sediments and to the buried sediments,and δ13C of TOC and organic fractions kept stable with depth,but differed distinctly among the four fractions.The different degradation rates oforganic compounds and the formation and degradation of bacteria organic matterare the major mechanisms causing the chemical and isotopic alteration oforganic matter duringearly diagenesis1 Because of the lower carbohydrate content in the plankton and the rapid degradation of lipid,the carbon isotopic fractionation caused by selective degradation of compounds could be relatively small and was partially canceled by the addition of bacterial synthesized organic matter,resultingin the observed conservative nature of δ13C duringearly diagenesis.On the other hand,the addition of bacteria organic matter may account for the depletion and variation of δ15N caused by early diagenesis.The above studies suggested that δ13C can be a reliable proxy to the sources of organic matter,but δ15N cannot be used to indicate the origin of sedimented o rganic matterin the study area.
2008, 30(5): 52-61.
Abstract:
Formation mechanismof the sizable hydrothermal sulfide deposit is a complex geological process involving many types of controlling factors. Mixing between hy drothermal fluid and seawater plays a key role in this process. The previous results of Ocean Drilling Program(ODP)indicate that mixing of the evolveds eawater with the hydrothermal fluid is wildly developed within the TAG hydrothermal deposit, which governs the internal structure and chemical compositions of the deposit to great extent. Taking example for the TAG field,the mixing process of the hydrothermal fluid is calculated with the seawater that is heated to different extent,in order to discuss the impact of hydrothermal fluid/seawater mixing on the formation process of the sulfide deposit. The results indicate that:(1)mixing between the heated seawater and the hydrothermal fluid derived from the deep deposit should be largely responsible for the wild precipitation of anhydrite within the TAG hydrothermal deposit;(2)330~310 is a special temperature zone in the mixing process between the seawater and the hydrothermal fluid;(3)the mixing and hydrothermal processes in differentareas(TAG-1,TAG-2 and TAG-5,etc)of the TAG hydrothermal deposithave been discussed based on the calculated results.
Formation mechanismof the sizable hydrothermal sulfide deposit is a complex geological process involving many types of controlling factors. Mixing between hy drothermal fluid and seawater plays a key role in this process. The previous results of Ocean Drilling Program(ODP)indicate that mixing of the evolveds eawater with the hydrothermal fluid is wildly developed within the TAG hydrothermal deposit, which governs the internal structure and chemical compositions of the deposit to great extent. Taking example for the TAG field,the mixing process of the hydrothermal fluid is calculated with the seawater that is heated to different extent,in order to discuss the impact of hydrothermal fluid/seawater mixing on the formation process of the sulfide deposit. The results indicate that:(1)mixing between the heated seawater and the hydrothermal fluid derived from the deep deposit should be largely responsible for the wild precipitation of anhydrite within the TAG hydrothermal deposit;(2)330~310 is a special temperature zone in the mixing process between the seawater and the hydrothermal fluid;(3)the mixing and hydrothermal processes in differentareas(TAG-1,TAG-2 and TAG-5,etc)of the TAG hydrothermal deposithave been discussed based on the calculated results.
2008, 30(5): 62-70.
Abstract:
Characteristics of faulting and magmatism of the Okinawa Trough and the relationship between them were focused on.Enechelon grabens are ranked oblique to the continental shelf edge uplift,and the Longwang uplift,the rifting block ridge in the northern trough and the "Mianhua uplift" in the southern trough have possibly preserved characteristics of volcanism and magmatismo ccurred with those rifting phases.The Tokara volcanic arc can be traced to Taiwan along the west slope of the Ry ky island arc.The clockwise rotation of the southern Ry ky-gunt,driven by collision between Luzon and Taiwan,has played a key role in the crustal oceanization,enhancing the crustal extension of the southern trough and inducing volcanic magmatism in those grabens,among which the Yaeyama grabenis a typical example of the presence of oceanic crust.Faultingand magmatism were mainly migrating towards the island are asymme-trically.The crustal oceanization of the Okinawa Trough is difficultly interpreted by the linear magnetica-nomaly model,which is fit for the symmetric spreading of the mid-oceanic ridges.
Characteristics of faulting and magmatism of the Okinawa Trough and the relationship between them were focused on.Enechelon grabens are ranked oblique to the continental shelf edge uplift,and the Longwang uplift,the rifting block ridge in the northern trough and the "Mianhua uplift" in the southern trough have possibly preserved characteristics of volcanism and magmatismo ccurred with those rifting phases.The Tokara volcanic arc can be traced to Taiwan along the west slope of the Ry ky island arc.The clockwise rotation of the southern Ry ky-gunt,driven by collision between Luzon and Taiwan,has played a key role in the crustal oceanization,enhancing the crustal extension of the southern trough and inducing volcanic magmatism in those grabens,among which the Yaeyama grabenis a typical example of the presence of oceanic crust.Faultingand magmatism were mainly migrating towards the island are asymme-trically.The crustal oceanization of the Okinawa Trough is difficultly interpreted by the linear magnetica-nomaly model,which is fit for the symmetric spreading of the mid-oceanic ridges.
2008, 30(5): 71-80.
Abstract:
Biomass size spectrum of planktonin the southern part of the Yellow Sea were analyzed based on the samples collected with nets of 70Lm,160 Lm and 505 Lm mesh size in September,2006.The individual size compositions and functional groups of plankton were also described and compared among the different waters in the neritic,central part and transition area of the Huanghai Sea.Results showed a constant size distribution of plankton individuals including phytoplankton(100 pg/ind~70ng/ind)and zooplankton(70 ng/ind~62 mg/ind).The distributions of Sheldon type biomass size spectra were curves with apparent peak,and those of normalized spectra were linear on a double log plot.The slope and intercept of normalized biomass spectra were -0.74 and 18.64 in the total stations,and they were -0.67 and 15.60 in central part,-0.64 and 14.34 in neritic and -0.73 and 18.03 in transition part of study area,respectively.Zooplankton diversity had more influences on the parameters of normalized biomass size spectra according to the correlation analysis.
Biomass size spectrum of planktonin the southern part of the Yellow Sea were analyzed based on the samples collected with nets of 70Lm,160 Lm and 505 Lm mesh size in September,2006.The individual size compositions and functional groups of plankton were also described and compared among the different waters in the neritic,central part and transition area of the Huanghai Sea.Results showed a constant size distribution of plankton individuals including phytoplankton(100 pg/ind~70ng/ind)and zooplankton(70 ng/ind~62 mg/ind).The distributions of Sheldon type biomass size spectra were curves with apparent peak,and those of normalized spectra were linear on a double log plot.The slope and intercept of normalized biomass spectra were -0.74 and 18.64 in the total stations,and they were -0.67 and 15.60 in central part,-0.64 and 14.34 in neritic and -0.73 and 18.03 in transition part of study area,respectively.Zooplankton diversity had more influences on the parameters of normalized biomass size spectra according to the correlation analysis.
2008, 30(5): 81-87.
Abstract:
Seasonal oceanographic cruises were conducted in the waters of the Changjiang Estuary(28b00c~32b00cN and 122b00c~123b30cE)from 2002 to 2003.Based on the data from the investigation,the seasonal distribution and abundance of pelagic Amphipoda in the Changjiang Estuary were dicussed through aqualitative and quantitative method.The relationship of pelagic Amphipoda abundance with the fish ground, the abundance variation of dominant species and thier contribution to pelagic Amphipoda abundance were all considered.It was found that the seasonal Amphipoda abundance was influenced by the seasonal surface temperature.Moreover,the horizontal distribution of its abundance was influenced by the surface salinity in the waters of the estuary.The abundance was the highest(2.75ind./m3)in summerand the lowest(0.10ind./m3)in winter.Of the 49 species identified,Monoculodes limnophilus and Lestrigonus schizogeneios were the mostly dominant species.Monoculodes limnophilus was dominant species in four seasons;it was the main dominant specie in spring,summerand autumn affected by the characteristics relatively low temperature warm adaptation compared with Lestrigonus schizo geneios who was dominant specie just in spring summer and autumn.The contribution of Lestrigonus schizogeneios to Amphipoda abundance was 0.87,higher than Monoculodes limnophilus in sum merattributed to tropical wateradaptation.There was a significant correlation between abundance and the surface temperature,and was no significant correlation with surface salinity.As animportant dietoffish in the Changjiang Estuary,the Amphipoda distributionis important in the fishingground there.
Seasonal oceanographic cruises were conducted in the waters of the Changjiang Estuary(28b00c~32b00cN and 122b00c~123b30cE)from 2002 to 2003.Based on the data from the investigation,the seasonal distribution and abundance of pelagic Amphipoda in the Changjiang Estuary were dicussed through aqualitative and quantitative method.The relationship of pelagic Amphipoda abundance with the fish ground, the abundance variation of dominant species and thier contribution to pelagic Amphipoda abundance were all considered.It was found that the seasonal Amphipoda abundance was influenced by the seasonal surface temperature.Moreover,the horizontal distribution of its abundance was influenced by the surface salinity in the waters of the estuary.The abundance was the highest(2.75ind./m3)in summerand the lowest(0.10ind./m3)in winter.Of the 49 species identified,Monoculodes limnophilus and Lestrigonus schizogeneios were the mostly dominant species.Monoculodes limnophilus was dominant species in four seasons;it was the main dominant specie in spring,summerand autumn affected by the characteristics relatively low temperature warm adaptation compared with Lestrigonus schizo geneios who was dominant specie just in spring summer and autumn.The contribution of Lestrigonus schizogeneios to Amphipoda abundance was 0.87,higher than Monoculodes limnophilus in sum merattributed to tropical wateradaptation.There was a significant correlation between abundance and the surface temperature,and was no significant correlation with surface salinity.As animportant dietoffish in the Changjiang Estuary,the Amphipoda distributionis important in the fishingground there.
2008, 30(5): 88-93.
Abstract:
A total of 408 specimens of Octopus tankahkeei were collected from the fishery in Xiangshan Bay,Zhejiang province between January 2003 and December 2003.The animals were grouped by sex,size and month for length frequency analysis,annual changes rhythmon biological indexes and major traits of body shape were examined.The results show:the monthly distributions of length frequency change greatly,which is wider in June and July than the others months,while there are two peaks in June(240 mm and 360mm,the percentage is 13.3% and 16.7% separately).The animals grow slowly in winter,while the rapid growth period occurred in March and April,juvenile octopus could be found in June and July after nearly 40 days hatching from spawning.There were significant differences between the individual indexes, such as TL/DL,TL/DK,and TL/V,of female and male by the statistics;there were significant differences in the DL,DK and Volume,which is larger of female's than that of maleps when the total length is equal.Additionally,the females are more width and embonpointthan males in body shape.
A total of 408 specimens of Octopus tankahkeei were collected from the fishery in Xiangshan Bay,Zhejiang province between January 2003 and December 2003.The animals were grouped by sex,size and month for length frequency analysis,annual changes rhythmon biological indexes and major traits of body shape were examined.The results show:the monthly distributions of length frequency change greatly,which is wider in June and July than the others months,while there are two peaks in June(240 mm and 360mm,the percentage is 13.3% and 16.7% separately).The animals grow slowly in winter,while the rapid growth period occurred in March and April,juvenile octopus could be found in June and July after nearly 40 days hatching from spawning.There were significant differences between the individual indexes, such as TL/DL,TL/DK,and TL/V,of female and male by the statistics;there were significant differences in the DL,DK and Volume,which is larger of female's than that of maleps when the total length is equal.Additionally,the females are more width and embonpointthan males in body shape.
Prediction of the heterosis in hybrids of red snapper Lutjanus erythropterus(♀)×L.sebae(♂)using RAPD
2008, 30(5): 94-99.
Abstract:
The heterosis of F1 hy brids(Lutjanus erythropterus ♀ × L.sebae ♂) was predicted with the RAPD method.35 arbitrary primers were screened to amplify the genomic DNA of these three populations of red snapper.190.distinct and highly reproducible RAPD bands with high genetic variability were detected and the frequency of polymorphism was 92.6%.Among the F1 population,L.erythropterus population and L.sebae population,the values of genetic identitiy were 0.726 3,0.831 9,0.916 8,respectively; the values of Nei's gene diversity were 0.264 0,0.174 5,0.118 4,respectively;the values of Shannons informationindex were 0.384 5,0.256 4,0.171 2,respectively,which all indicated that F1 populations showed greater genetic diversity than parental populations.Furthermore,the genetic distance between hybrid populations and L.erythropterus ♀ was 0.397 2,0.317 2 between hybrid populations and L.sebae ♂ and 0.854 1 between L.erythropterus ♀ and L.sebae ♂.The data of S,H and I all showed that F1 owned the potential heterosis.Finally,some species-specific markers were found.
The heterosis of F1 hy brids(Lutjanus erythropterus ♀ × L.sebae ♂) was predicted with the RAPD method.35 arbitrary primers were screened to amplify the genomic DNA of these three populations of red snapper.190.distinct and highly reproducible RAPD bands with high genetic variability were detected and the frequency of polymorphism was 92.6%.Among the F1 population,L.erythropterus population and L.sebae population,the values of genetic identitiy were 0.726 3,0.831 9,0.916 8,respectively; the values of Nei's gene diversity were 0.264 0,0.174 5,0.118 4,respectively;the values of Shannons informationindex were 0.384 5,0.256 4,0.171 2,respectively,which all indicated that F1 populations showed greater genetic diversity than parental populations.Furthermore,the genetic distance between hybrid populations and L.erythropterus ♀ was 0.397 2,0.317 2 between hybrid populations and L.sebae ♂ and 0.854 1 between L.erythropterus ♀ and L.sebae ♂.The data of S,H and I all showed that F1 owned the potential heterosis.Finally,some species-specific markers were found.
2008, 30(5): 100-106.
Abstract:
Owing to selecting the strains of high temperature resistance,F3 generation of new strains coming from hybridizationin Porphyra haitanensis(Z-26,Z-61,Z-81,Z-17)was compared with the wild-type control group by inheritable traits.Results indicated that:(1)The four new strains of selective filament strains could normally growand develop after 40 d cultivated at 29℃ high temperature.Such as Z-26 filament grew faster;Z-61 was easily mature and 95% of the conchocelis filament sprouted into sporangial branch.There was only 30% of filament sprouted into sporangial branch in Z-17.(2)Z-26 and Z-61 were cultivated 10 d under the temperature of 30℃.Then they turned white but were not dead and could return theirintrinsical colour after 3~4 d cultivated at 21℃.(3)Blades of Z-81 and Z-17 which were cultivated 7~10 d at 29℃ turned white but were not dead and could return normal at 21℃.However,when cultivated 10 d under the temperature of 30℃,they were rotten and could not be recovered.(4) Wild-type control group was no high temperature resistance and they were rotten even dead after 5 days cultivated under the temperature of 27℃.The four stains of slection could resistthe high temperature, 1~3℃ higher,comparing with the wild-type control group.(5)The thallus of the four strains were cultivatied 10 d under the temperature of 26~28℃ and their main phycobiliprotein and chlorophyll a were quiet variance comparing with the thallus that were cultivated under the temperature of 21℃.It indicated thattemporary high temperature did not make effect on their quality.
Owing to selecting the strains of high temperature resistance,F3 generation of new strains coming from hybridizationin Porphyra haitanensis(Z-26,Z-61,Z-81,Z-17)was compared with the wild-type control group by inheritable traits.Results indicated that:(1)The four new strains of selective filament strains could normally growand develop after 40 d cultivated at 29℃ high temperature.Such as Z-26 filament grew faster;Z-61 was easily mature and 95% of the conchocelis filament sprouted into sporangial branch.There was only 30% of filament sprouted into sporangial branch in Z-17.(2)Z-26 and Z-61 were cultivated 10 d under the temperature of 30℃.Then they turned white but were not dead and could return theirintrinsical colour after 3~4 d cultivated at 21℃.(3)Blades of Z-81 and Z-17 which were cultivated 7~10 d at 29℃ turned white but were not dead and could return normal at 21℃.However,when cultivated 10 d under the temperature of 30℃,they were rotten and could not be recovered.(4) Wild-type control group was no high temperature resistance and they were rotten even dead after 5 days cultivated under the temperature of 27℃.The four stains of slection could resistthe high temperature, 1~3℃ higher,comparing with the wild-type control group.(5)The thallus of the four strains were cultivatied 10 d under the temperature of 26~28℃ and their main phycobiliprotein and chlorophyll a were quiet variance comparing with the thallus that were cultivated under the temperature of 21℃.It indicated thattemporary high temperature did not make effect on their quality.
2008, 30(5): 107-112.
Abstract:
The internal transcribed spacer(ITS)region offive strains which collected from Norway,English Channel,New Zealand,U.S.and Qingdao(China)was amplified with polymerase chain-reaction (PCR)and sequenced.Pairwise distance and percentidentity between ITS sequence of the 5 strains and others retrieved from GenBank were ccalculated.The phylogenetic trees(NJ and ME)were constructed with the ITS sequences which linked to other Raphidophyceae.Results showed that the sequence of 5 strains was identical,which was 538 bp,only one base pair different fromo ther four strains saved in GenBank.Pairwise distance and percent identity are 0.002 and 0.098,respectively.Otherwise completed identical sequences had been found when compared with other strains.The phylogenetic trees constructed by two methods showed totally same results.The Heterosig ma had a close relationship with Chattonella, while was distant fromother two classes.
The internal transcribed spacer(ITS)region offive strains which collected from Norway,English Channel,New Zealand,U.S.and Qingdao(China)was amplified with polymerase chain-reaction (PCR)and sequenced.Pairwise distance and percentidentity between ITS sequence of the 5 strains and others retrieved from GenBank were ccalculated.The phylogenetic trees(NJ and ME)were constructed with the ITS sequences which linked to other Raphidophyceae.Results showed that the sequence of 5 strains was identical,which was 538 bp,only one base pair different fromo ther four strains saved in GenBank.Pairwise distance and percent identity are 0.002 and 0.098,respectively.Otherwise completed identical sequences had been found when compared with other strains.The phylogenetic trees constructed by two methods showed totally same results.The Heterosig ma had a close relationship with Chattonella, while was distant fromother two classes.
2008, 30(5): 113-123.
Abstract:
Laboratory experiments on the instability of alongshore currents were performed on a plane beach with slope 1:40.Low-frequency fluctuations of along shore currents with the period of approximately 100 s were observed.The dominant frequency and amplitude of the oscillations of along shore currents were determined using maximumentropy method and the regression method of trigonometric function,and the results showed that the variations of the amplitude of the alongshore current oscillations were similar to the variations of the mean along shore currents in the cross-shore direction.The linear shearinstability theory was used to analyze the mechanism of the oscillation,and the calculated results agreed with measurements.This confirms that the observed fluctuations of along shore currents are due to the shearinstability of alongshore currents.
Laboratory experiments on the instability of alongshore currents were performed on a plane beach with slope 1:40.Low-frequency fluctuations of along shore currents with the period of approximately 100 s were observed.The dominant frequency and amplitude of the oscillations of along shore currents were determined using maximumentropy method and the regression method of trigonometric function,and the results showed that the variations of the amplitude of the alongshore current oscillations were similar to the variations of the mean along shore currents in the cross-shore direction.The linear shearinstability theory was used to analyze the mechanism of the oscillation,and the calculated results agreed with measurements.This confirms that the observed fluctuations of along shore currents are due to the shearinstability of alongshore currents.
2008, 30(5): 124-136.
Abstract:
On the basis of the measurement of current velocity within the water column,water depth and physical properties of seawaterover the Taiwan Bank in August 2006,the spatial and temporal characteristics of current velocities over large-scale sandwaves,together with the process of sediment transport,are analyzed.The results show that the sandwaves,14.4~20.3 min heightand 325.4~821.8 min length, are formed under the conditions of strong currentthat is acting upon the bed consisting of coarse-grained sediments,with a height-length relationship similar to those identified elsewhere in previous studies.Currents at the sandwave crest,trough,stoss-side and lee-side turn in a clockwise manner with a period of 12.5 h.In the bottom layer of the water column,the largest velocity occurred at the same phase of each semidiurnal cycle,which was directed to the south;furthermore,the velocities on the stoss-side are larger than on the lee-side.During the two semidiurnal tidal cycles,the amount of sediment im ported into the study area was larger than out put,indicating that accretion was taking place.The sediment transported by tidal current was relatively weak,which could cause only slow migration of sandwaves.However,according to satel lite observations,the sandwave migration can be high over the Taiwan Bank.This phenomenon may be caused by the strong currents asso ciated with storm events.At the cross-section studied,sediment transport was more intensive during the flood than during the ebb,and the net fluxes varied for different semidiurnal tidal cycles,indicating the effects of the time-velocity asymmetry and the tide phase.
On the basis of the measurement of current velocity within the water column,water depth and physical properties of seawaterover the Taiwan Bank in August 2006,the spatial and temporal characteristics of current velocities over large-scale sandwaves,together with the process of sediment transport,are analyzed.The results show that the sandwaves,14.4~20.3 min heightand 325.4~821.8 min length, are formed under the conditions of strong currentthat is acting upon the bed consisting of coarse-grained sediments,with a height-length relationship similar to those identified elsewhere in previous studies.Currents at the sandwave crest,trough,stoss-side and lee-side turn in a clockwise manner with a period of 12.5 h.In the bottom layer of the water column,the largest velocity occurred at the same phase of each semidiurnal cycle,which was directed to the south;furthermore,the velocities on the stoss-side are larger than on the lee-side.During the two semidiurnal tidal cycles,the amount of sediment im ported into the study area was larger than out put,indicating that accretion was taking place.The sediment transported by tidal current was relatively weak,which could cause only slow migration of sandwaves.However,according to satel lite observations,the sandwave migration can be high over the Taiwan Bank.This phenomenon may be caused by the strong currents asso ciated with storm events.At the cross-section studied,sediment transport was more intensive during the flood than during the ebb,and the net fluxes varied for different semidiurnal tidal cycles,indicating the effects of the time-velocity asymmetry and the tide phase.
2008, 30(5): 137-142.
Abstract:
In order to find a simple,continuous method to measure suspended sediment content in a high turbidity region,experiments were conducted to examine relationship between suspended sediment contentand electrical conductivity.Sediments from the Huanghe River Delta and a conductivity sensor were used. The influencing factors of influencing this relationship were also investigated.The results show that good linear relationships exist between suspended sediment contentand electrical conductivity;salinity and grain-size have some influence on the electrical conductivity,of which salinity is the most influencing facto rand grain-size has little influence.The linear relationships suggest that it is feasible to measure suspended sediment content in situ using the electrical conductivity sensor.
In order to find a simple,continuous method to measure suspended sediment content in a high turbidity region,experiments were conducted to examine relationship between suspended sediment contentand electrical conductivity.Sediments from the Huanghe River Delta and a conductivity sensor were used. The influencing factors of influencing this relationship were also investigated.The results show that good linear relationships exist between suspended sediment contentand electrical conductivity;salinity and grain-size have some influence on the electrical conductivity,of which salinity is the most influencing facto rand grain-size has little influence.The linear relationships suggest that it is feasible to measure suspended sediment content in situ using the electrical conductivity sensor.
2008, 30(5): 143-150.
Abstract:
A coupling model ofinteraction of wave with porous medium with large porosity is established. The wave field solveris based on the two-dimensional Reynolds averaged Navier-Stokes(RANS)equations with a k-ε closure.A piston-type wave makeris setup in the computational domain to produce incident waves and the free surface is traced through the piecewise linear interface construction-volume off luid.The incident waves can be the linear wave,the cnoidal waves and the solitary waves.For chheimer equations are adopted in porous flow within the porous media.By introducinga velocity-pressure correction equation for the waves and the porous flow,highly efficient coupling between the two flows is realized.The two flows can be solved simultaneously and no boundary condition is needed on the interface between them.It was found that the proposed model is effective for studying interaction of wave with scree seabed and is able to handle the water waves and the submerged porous breakwateron flat and slope beds.The verified numerical model can be used to study the interaction between waves and porous medium with large porosity.
A coupling model ofinteraction of wave with porous medium with large porosity is established. The wave field solveris based on the two-dimensional Reynolds averaged Navier-Stokes(RANS)equations with a k-ε closure.A piston-type wave makeris setup in the computational domain to produce incident waves and the free surface is traced through the piecewise linear interface construction-volume off luid.The incident waves can be the linear wave,the cnoidal waves and the solitary waves.For chheimer equations are adopted in porous flow within the porous media.By introducinga velocity-pressure correction equation for the waves and the porous flow,highly efficient coupling between the two flows is realized.The two flows can be solved simultaneously and no boundary condition is needed on the interface between them.It was found that the proposed model is effective for studying interaction of wave with scree seabed and is able to handle the water waves and the submerged porous breakwateron flat and slope beds.The verified numerical model can be used to study the interaction between waves and porous medium with large porosity.
2008, 30(5): 151-158.
Abstract:
2008, 30(5): 159-164.
Abstract:
2008, 30(5): 165-170.
Abstract:
2008, 30(5): 171-176.
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