2007 Vol. 29, No. 4
Display Method:
2007, 29(4): 1-10.
Abstract:
The aim of this paper is to analyze the interannual variation of temperature and salinity of the northern Huanghai Sea Cold Water Mass(NHC)and factors leading to this variation,based on data collected during 1976~1999.The result soutline linear trends of NHC temperature by+0.005 e/a,while salinity doesn't have an obviously upward or dowmward trend.Winter air temperature is the main factor affecting the NHC temperature.But NHC temperature would be higher after Kuroshio Meander appeared. The salinity variation of NHC is the co-effect of Huanghai Sea Warm Current,heat flux of Bohai Sea and strong wind in winter.Freshwater in Huanghe River is not the main factor leads to the yearly variation of the NHC salinity,but its variation in a huge value would affect the trends of the NHC salinity.
The aim of this paper is to analyze the interannual variation of temperature and salinity of the northern Huanghai Sea Cold Water Mass(NHC)and factors leading to this variation,based on data collected during 1976~1999.The result soutline linear trends of NHC temperature by+0.005 e/a,while salinity doesn't have an obviously upward or dowmward trend.Winter air temperature is the main factor affecting the NHC temperature.But NHC temperature would be higher after Kuroshio Meander appeared. The salinity variation of NHC is the co-effect of Huanghai Sea Warm Current,heat flux of Bohai Sea and strong wind in winter.Freshwater in Huanghe River is not the main factor leads to the yearly variation of the NHC salinity,but its variation in a huge value would affect the trends of the NHC salinity.
2007, 29(4): 11-19.
Abstract:
An experiment of establishing a forecasting model of tropical cyclones(TCs)intensity was undertaken by using genetic algorithm and artificial neural network in combination,base on the data of TCs over the South China Sea area in July and August respectively for the period of 1960~2001.Furthermore,by making a comparative analysis of the forecasting result between the genetic algorithm combining with artificial neural network and the Climatology and Persistence(CLIPER)methods base on the same TCs sample.It showed that the former method had better capacity of TCs intensity forecasting than the latter.
An experiment of establishing a forecasting model of tropical cyclones(TCs)intensity was undertaken by using genetic algorithm and artificial neural network in combination,base on the data of TCs over the South China Sea area in July and August respectively for the period of 1960~2001.Furthermore,by making a comparative analysis of the forecasting result between the genetic algorithm combining with artificial neural network and the Climatology and Persistence(CLIPER)methods base on the same TCs sample.It showed that the former method had better capacity of TCs intensity forecasting than the latter.
2007, 29(4): 20-33.
Abstract:
Using the coupled bio-physical model described in the first paper of this series of studies,the annual variations of algae biomass and nutrient concentration in Bohai Seawer esimulated.Modeled results show that the onset of spring bloom is induced by high nutrient stocks stored in the winter,though the initial time is earlier in shallow waters than in deep waters,for which the evolution of the vertical stratification in deep waters plays the important role;on the other hand,newly added river-borne nutrients and resuspending sediment-borne nutrients are responsible for the out burst of autumn blooms.Based on modeled results,it is also found that the BS ecosystem,as a whole,is limited by nitrogen all the year round, though the phosphorus limitation is apparent in Laizhou Bay where the N/P ratio is higher than 16 due to the contribution of newly added nutrient species from Huanghe River discharges.
Using the coupled bio-physical model described in the first paper of this series of studies,the annual variations of algae biomass and nutrient concentration in Bohai Seawer esimulated.Modeled results show that the onset of spring bloom is induced by high nutrient stocks stored in the winter,though the initial time is earlier in shallow waters than in deep waters,for which the evolution of the vertical stratification in deep waters plays the important role;on the other hand,newly added river-borne nutrients and resuspending sediment-borne nutrients are responsible for the out burst of autumn blooms.Based on modeled results,it is also found that the BS ecosystem,as a whole,is limited by nitrogen all the year round, though the phosphorus limitation is apparent in Laizhou Bay where the N/P ratio is higher than 16 due to the contribution of newly added nutrient species from Huanghe River discharges.
2007, 29(4): 34-42.
Abstract:
Acouso-physical properties of seafloor sediments in the southeast offshore sea area of Hainan Island at the northern continental shelf of South China Sea are analyzed.In many cruises CTD measurements of seawater,measurments of shallow stratum and side-scan sonar have been made.Acoustic parameters, basic sedimentary parameters,physico-mechanical parameters and 14C age,etc.have been measured.Sedi-menteastic parameters,including Young's modulus,bulk modulus,constrained modulus,rigidity modulus,Poisson's ratio,Lames constant,etc.,have been calculated.Results show that the compression wave velocity of the seafloor sediment in the sea area ranges from 1.474 to 1.700 km/s,and there are high and low sound velocity sediment types in the different sea areas;the shear wave velocity is 150~600 m/s;at 100 kHz the sediment sound attenuation is 35~260 dB/m,the sediment density is 1.4~2.0 g/cm3;the sediment porosity is 42%~88%.Sound field parameters and describing sound reciprocity between sea and seafloor are described.
Acouso-physical properties of seafloor sediments in the southeast offshore sea area of Hainan Island at the northern continental shelf of South China Sea are analyzed.In many cruises CTD measurements of seawater,measurments of shallow stratum and side-scan sonar have been made.Acoustic parameters, basic sedimentary parameters,physico-mechanical parameters and 14C age,etc.have been measured.Sedi-menteastic parameters,including Young's modulus,bulk modulus,constrained modulus,rigidity modulus,Poisson's ratio,Lames constant,etc.,have been calculated.Results show that the compression wave velocity of the seafloor sediment in the sea area ranges from 1.474 to 1.700 km/s,and there are high and low sound velocity sediment types in the different sea areas;the shear wave velocity is 150~600 m/s;at 100 kHz the sediment sound attenuation is 35~260 dB/m,the sediment density is 1.4~2.0 g/cm3;the sediment porosity is 42%~88%.Sound field parameters and describing sound reciprocity between sea and seafloor are described.
2007, 29(4): 43-50.
Abstract:
On the basis of comparison of physical significance and applicability of single-parameter,double-parameter and multi-parameter sound velocity forecasting empirical equation of seafloor sediments,a new porosity-water-content double-parameter equation is put forward.This equation avoids short comings in the single-parameter and some double-parameter equations with ambiguity of physical significance and complexity in the multi-parameter equation also.Atheoretical analysis is carried out and a correctional porosity-water-content double-parameter equation is set up to act as universal model which has explicit physical significance and high generalization capability by correcting coefficients.As to comparison of weightings of porosity and water content,a key role of porosity among all parameters is confirmed.Measurement data of study samples from the northern Taiwan Strait,the South China Sea and the Zhujiang mouth continental shelfare applied to verifying the superiority of porosity-water-content double-parameter equation set up in contrast with other equations.
On the basis of comparison of physical significance and applicability of single-parameter,double-parameter and multi-parameter sound velocity forecasting empirical equation of seafloor sediments,a new porosity-water-content double-parameter equation is put forward.This equation avoids short comings in the single-parameter and some double-parameter equations with ambiguity of physical significance and complexity in the multi-parameter equation also.Atheoretical analysis is carried out and a correctional porosity-water-content double-parameter equation is set up to act as universal model which has explicit physical significance and high generalization capability by correcting coefficients.As to comparison of weightings of porosity and water content,a key role of porosity among all parameters is confirmed.Measurement data of study samples from the northern Taiwan Strait,the South China Sea and the Zhujiang mouth continental shelfare applied to verifying the superiority of porosity-water-content double-parameter equation set up in contrast with other equations.
2007, 29(4): 51-58.
Abstract:
With the MODIS data from 2001 to 2005,areas of the tidal flats in the coastal zone of Fujian Province in China are calculated utilizing the band ratio of MODIS 250 m resolution of visible and near infrared band to high tidal level and low tidal level,and the results are verified by the 30 m resolution Land-sat-7/ETM+ satellite image of the Luoyuan Bay and the Fuqing Bay.The results show that the observation time of MODISdat a is close to the time of high tidal level and low tidal level,thus the tidal flatre-source monito ring can be done easily.The areas of tidal flats calculated by the MODIS data are larger somewhat in contrast to the high resolution Landsat-7/ETM+ data.The results of remote sensing monito ring show that the tidal flat areas in the coastal zone of Fujian Province have decreased 107 km2 between 1986 and 2001,and the tidal flat areas also presented a drop tendency year by year from 2001 to 2005.
With the MODIS data from 2001 to 2005,areas of the tidal flats in the coastal zone of Fujian Province in China are calculated utilizing the band ratio of MODIS 250 m resolution of visible and near infrared band to high tidal level and low tidal level,and the results are verified by the 30 m resolution Land-sat-7/ETM+ satellite image of the Luoyuan Bay and the Fuqing Bay.The results show that the observation time of MODISdat a is close to the time of high tidal level and low tidal level,thus the tidal flatre-source monito ring can be done easily.The areas of tidal flats calculated by the MODIS data are larger somewhat in contrast to the high resolution Landsat-7/ETM+ data.The results of remote sensing monito ring show that the tidal flat areas in the coastal zone of Fujian Province have decreased 107 km2 between 1986 and 2001,and the tidal flat areas also presented a drop tendency year by year from 2001 to 2005.
2007, 29(4): 59-68.
Abstract:
Surface waters were collected from the Jiulong River Estuary for determination of activity concent rations of uranium isotopes in different size fractions,namely,>53 Lm,10~53 Lm,2~10 Lm, 0.4~2 Lm,10 000 u~0.4 Lm and<10 000 u fractions by microfiltration and crossOflow ultrafiltration techniques.Our results indicated that most of the dissolved uranium(<0.4 Lm)existed in the low molecular mass fraction(<10 000 u),and the colloidal 238U(10 000 u~0.4 Lm)only contributed <1% of the dissolved 238U.The fractions of colloidal uranium in the dissolved phases decreased with the increasing salinity.
Surface waters were collected from the Jiulong River Estuary for determination of activity concent rations of uranium isotopes in different size fractions,namely,>53 Lm,10~53 Lm,2~10 Lm, 0.4~2 Lm,10 000 u~0.4 Lm and<10 000 u fractions by microfiltration and crossOflow ultrafiltration techniques.Our results indicated that most of the dissolved uranium(<0.4 Lm)existed in the low molecular mass fraction(<10 000 u),and the colloidal 238U(10 000 u~0.4 Lm)only contributed <1% of the dissolved 238U.The fractions of colloidal uranium in the dissolved phases decreased with the increasing salinity.
2007, 29(4): 69-76.
Abstract:
Dissolved and particulate 234Th,particulate organic carbon in the upper 150 m of water columns from five stations in the Prydz Bay,Southern Ocean were determined during the 22nd Chinese National Antarctic Research Expedition(from Nov.2005 to Mar.2006).The disequilibria between 234Th and its parent 238U in upper layer was used to derive the average residence time of 234Th,which decreased along with the latitude toward south with minimum values,respectively 1~8 d for particulate 234Th and 29~48 d for dissolved 234Th,appeared at the medium latitude station,and the export fluxes of 234Th were calculated too and max values,respectively 21~38 dpm/(m2·d)for particulate 234Th and 26~39 dpm/(m2·d) for dissolved 234Th,appeared at the same station.The export fluxes of particulate organic carbon at different water columns were derived by two methods with irreversible scavenging model,and the average value were 104.7 mmol/(m2·d)(E method)and 120.6 mmol/(m2·d)(B method),respectively,which meant in summer relatively high new production existed in the Prydz Bay where would play a significant role as CO2 sink.
Dissolved and particulate 234Th,particulate organic carbon in the upper 150 m of water columns from five stations in the Prydz Bay,Southern Ocean were determined during the 22nd Chinese National Antarctic Research Expedition(from Nov.2005 to Mar.2006).The disequilibria between 234Th and its parent 238U in upper layer was used to derive the average residence time of 234Th,which decreased along with the latitude toward south with minimum values,respectively 1~8 d for particulate 234Th and 29~48 d for dissolved 234Th,appeared at the medium latitude station,and the export fluxes of 234Th were calculated too and max values,respectively 21~38 dpm/(m2·d)for particulate 234Th and 26~39 dpm/(m2·d) for dissolved 234Th,appeared at the same station.The export fluxes of particulate organic carbon at different water columns were derived by two methods with irreversible scavenging model,and the average value were 104.7 mmol/(m2·d)(E method)and 120.6 mmol/(m2·d)(B method),respectively,which meant in summer relatively high new production existed in the Prydz Bay where would play a significant role as CO2 sink.
2007, 29(4): 77-86.
Abstract:
Water samples for suspended particles in water column were collected at 3 stations in the China Pioneer Area of Multi-metallic Nodules,the northeastern Pacific Ocean in July 2005.The samples of suspended particles were analyzed by ICP-MS,and contents of 47 elements from the particles were obtained. The barium and aluminum were chosen as the biogenic and terrigenous source tracers for the suspended particles,respectively.The barium contentranges from 0.02 to 0.19 μg/dm3 with the bio-barium content range from 0.01 to 0.13 μg/dm3,and the aluminum content ranges from 0.33 to 18.54 μg/dm3.The distribution of the bio-barium and aluminum of suspended particles and their ratio from the surface to the bottom in the water column corresponding to that of the TSM,which can be divided into three parts,was mainly caused by the distribution of biological process in the euphotic layer and the resuspension process of the seafloor sediment in the benthic layer.The decreasing tendency of the ratio of bio-barium to aluminum from marine benthic layer down to the seafloor reveals the evident change of the content and component of the suspended particles caused by the resuspended seafloor sediment in the benthic layer.Thus,their ratio can be regarded as an effective tracer of suspended particles exchange and transport in the benthic nepheloid layer.
Water samples for suspended particles in water column were collected at 3 stations in the China Pioneer Area of Multi-metallic Nodules,the northeastern Pacific Ocean in July 2005.The samples of suspended particles were analyzed by ICP-MS,and contents of 47 elements from the particles were obtained. The barium and aluminum were chosen as the biogenic and terrigenous source tracers for the suspended particles,respectively.The barium contentranges from 0.02 to 0.19 μg/dm3 with the bio-barium content range from 0.01 to 0.13 μg/dm3,and the aluminum content ranges from 0.33 to 18.54 μg/dm3.The distribution of the bio-barium and aluminum of suspended particles and their ratio from the surface to the bottom in the water column corresponding to that of the TSM,which can be divided into three parts,was mainly caused by the distribution of biological process in the euphotic layer and the resuspension process of the seafloor sediment in the benthic layer.The decreasing tendency of the ratio of bio-barium to aluminum from marine benthic layer down to the seafloor reveals the evident change of the content and component of the suspended particles caused by the resuspended seafloor sediment in the benthic layer.Thus,their ratio can be regarded as an effective tracer of suspended particles exchange and transport in the benthic nepheloid layer.
2007, 29(4): 87-96.
Abstract:
The tectonic movement at the end of Cretacious and the beginning of Cenozoic had opened the Cenozoic phase of poly cyclic tectonic movement,then the whole crust of the South China Sea had been mainly subjected to the regional stress field of tectonic tension,which was characterized by rifting depression.Seven times of regional tectonic movement and sedimentation had been assembled into ageological development history of polycyclic oscillatory.Especially,the tectonic movement was strongly intensified at the end of Cretacious and the beginning of Paleagene,between the Late Eocene and the Mid-Oligocene, during the Mid-and Late Miocene.These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea.Crust movement of the South China Sea was the result and epitome of interaction of the Eurasia,Pacific and Indo)Australia plates,that is,they were introduced by polycyclic changes of directions,rates and strengths of lithospheric movement and asthenospheric flow covering across the Pacific and Indo)Australia plates.
The tectonic movement at the end of Cretacious and the beginning of Cenozoic had opened the Cenozoic phase of poly cyclic tectonic movement,then the whole crust of the South China Sea had been mainly subjected to the regional stress field of tectonic tension,which was characterized by rifting depression.Seven times of regional tectonic movement and sedimentation had been assembled into ageological development history of polycyclic oscillatory.Especially,the tectonic movement was strongly intensified at the end of Cretacious and the beginning of Paleagene,between the Late Eocene and the Mid-Oligocene, during the Mid-and Late Miocene.These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea.Crust movement of the South China Sea was the result and epitome of interaction of the Eurasia,Pacific and Indo)Australia plates,that is,they were introduced by polycyclic changes of directions,rates and strengths of lithospheric movement and asthenospheric flow covering across the Pacific and Indo)Australia plates.
2007, 29(4): 97-104.
Abstract:
Characteristics and distribution patterns of clastic minerals(0.063~0.125 mm in grain diameter) in bottom sediments are a significant indicat or for the identification of the origin of sediment.114 surface sediment samples,which were collected from the area near the Zhongsha Islands in the South China Sea, were analysed to identify the mineral suites and the their distributions in the study area.The area can be divided into three mineral provinces.Province Ⅰ of biogenic minerals:Amineral assemblage is very simple and is made up of the biogenic detritus minerals,except that the biogenic minerals are mainly originated from the Zhongsha Atoll,a very small quantity of volcano genic minerals and terrigeno us minerals can be transported into this province by means of wind and suspension.Province Ⅱ of volcanogenic mineral: Light minerals in this province mainly include brown volcanic glass,volcanic scoria and color less volcanic glass;the mineral assemblage in this province is made up of brown volcanic glass and volcanic scoria;the content of weathering detritus and terrigeno us minerals is very low;the volcanic scoria in this province takes on distribution pattern from "point source"diffusion;the material source of this province is relatively complicated;the detrital minerals are mainly derived from local basaltic seamounts and small-scale volcanoes that are probably erupting,with some influences from the island-arcvolcanic region around the South China Sea,and island-arc-volcanic regions around this study area have a little influence on modern sedimentation in the study area.Mixed mineral province Ⅲ,in which the material source includes biogenic minerals,volcano genic minerals and terrigenous minerals.The last province can be subdivided into a mixed mineral sub-province Ⅲ-1.of the northeastern part of the study area,the mineral assemblage mainly includes biogenic detritus minerals,brown volcanic glass,quartz and feldspar.in which terrigeno us minerals are mainly derived from China's Mainland and do not exceed 17°N;and a mixed mineral sub-province Ⅲ-2 of the southeastern part of the study area,the mineral assemblage is biogenic detritus minerals,brown volcanic glass, quartz and weathered detritus,terrigenous minerals in this area are derived from Kalimantan and Indo-China Peninsula and might be further transported into the deep-sea basin through submarine canyons.
Characteristics and distribution patterns of clastic minerals(0.063~0.125 mm in grain diameter) in bottom sediments are a significant indicat or for the identification of the origin of sediment.114 surface sediment samples,which were collected from the area near the Zhongsha Islands in the South China Sea, were analysed to identify the mineral suites and the their distributions in the study area.The area can be divided into three mineral provinces.Province Ⅰ of biogenic minerals:Amineral assemblage is very simple and is made up of the biogenic detritus minerals,except that the biogenic minerals are mainly originated from the Zhongsha Atoll,a very small quantity of volcano genic minerals and terrigeno us minerals can be transported into this province by means of wind and suspension.Province Ⅱ of volcanogenic mineral: Light minerals in this province mainly include brown volcanic glass,volcanic scoria and color less volcanic glass;the mineral assemblage in this province is made up of brown volcanic glass and volcanic scoria;the content of weathering detritus and terrigeno us minerals is very low;the volcanic scoria in this province takes on distribution pattern from "point source"diffusion;the material source of this province is relatively complicated;the detrital minerals are mainly derived from local basaltic seamounts and small-scale volcanoes that are probably erupting,with some influences from the island-arcvolcanic region around the South China Sea,and island-arc-volcanic regions around this study area have a little influence on modern sedimentation in the study area.Mixed mineral province Ⅲ,in which the material source includes biogenic minerals,volcano genic minerals and terrigenous minerals.The last province can be subdivided into a mixed mineral sub-province Ⅲ-1.of the northeastern part of the study area,the mineral assemblage mainly includes biogenic detritus minerals,brown volcanic glass,quartz and feldspar.in which terrigeno us minerals are mainly derived from China's Mainland and do not exceed 17°N;and a mixed mineral sub-province Ⅲ-2 of the southeastern part of the study area,the mineral assemblage is biogenic detritus minerals,brown volcanic glass, quartz and weathered detritus,terrigenous minerals in this area are derived from Kalimantan and Indo-China Peninsula and might be further transported into the deep-sea basin through submarine canyons.
2007, 29(4): 105-110.
Abstract:
The genetic diversity and population genetic structure of 54 H.nitens samples from three stocks (18 from cultured stock in Zhelin Bay,18 from cultured stock in Xiamen Bay and 18 from wild stock in Xiamen of fing)were studied using the inter-simple sequence repeat(ISSR)marker.The ISSR bands can be differentiated highly in 17 primers after screening.A total of 145 discernible DNA fragments were observed,among which 80 fragments(55.17%)being poly morphic.The percentage of polymorphic(PPB), Nei's gene diversity and Shannon's index(calculated in POPGENE(in small capital))showed that the wild stock in Xiamen had the highest genetic variation(PPB=51.72%,h=0.182 6,I=0.2719).The inter-stocks Nei's gene diversity coefficient and gene flow were 0.0876 and 5.2098 respectively,indicating that the genetic difference among three stocks hasn't reached the population level yet.
The genetic diversity and population genetic structure of 54 H.nitens samples from three stocks (18 from cultured stock in Zhelin Bay,18 from cultured stock in Xiamen Bay and 18 from wild stock in Xiamen of fing)were studied using the inter-simple sequence repeat(ISSR)marker.The ISSR bands can be differentiated highly in 17 primers after screening.A total of 145 discernible DNA fragments were observed,among which 80 fragments(55.17%)being poly morphic.The percentage of polymorphic(PPB), Nei's gene diversity and Shannon's index(calculated in POPGENE(in small capital))showed that the wild stock in Xiamen had the highest genetic variation(PPB=51.72%,h=0.182 6,I=0.2719).The inter-stocks Nei's gene diversity coefficient and gene flow were 0.0876 and 5.2098 respectively,indicating that the genetic difference among three stocks hasn't reached the population level yet.
2007, 29(4): 111-119.
Abstract:
Taking the Portunus trituberculatus larvas as testing animal,the research of the effects of the short-period fasting on survival and metamorphosis of Portunus trituberculatus larvas was carried out in Huaxing marine fry Ltd1 of Zhoushan city,Zhejiang province in April,2005.The results showed that: the average complete lethal time of Portunus trituberculatus larvas juvenile(Z1,Z2,Z3,Z4 to M)was 81, 120,141,162 and 200 h respectively,and the median lethal time was 39,66,90,64 and 174 h respectively. The displaying time of metamorphosis point was 33,57,69,54 and 150 h respectively under the condition of re-feeding recovering after the short-fasting.When the single fasting time was inside of the displaying time of metamorphosis point,the survival rate and metamorphosis rate were both declined,the larva metamor-phosis time prolonged and the death rate of anomalism was increased as the fasting time extending.There was no difference between the Z1(group of starving for 3 h and the group of the recurring mode of/feeding for 3 h then fasting for 3 h0).The results of Z2,Z2,Z4,M is same as the Z1(Z2 is between the group of fasting for 4 h and the group of recurring mode of/feeding for 4 h then fasting for 4 h0,Z3 is between the group of fasting for 4.5 h and the group of recurring mode of/feeding for 4.5 h then fasting for 4.5 h0, Z4 is between the group of fasting for 6 h and the group of recurring mode of/feeding for 6 h then fasting for 6 h,M is be ween the group of fasting for 7.5 h,fasting 15 h and the group of recurring mode of/feeding for 6 h then fasting for 6 h0).Finally,the thesis discussed the definition of fasting limit value and the total restricted disposing time,and the survival and metamorphosis character under short-period starvation of different period of Portunus trituberculatus larvas.
Taking the Portunus trituberculatus larvas as testing animal,the research of the effects of the short-period fasting on survival and metamorphosis of Portunus trituberculatus larvas was carried out in Huaxing marine fry Ltd1 of Zhoushan city,Zhejiang province in April,2005.The results showed that: the average complete lethal time of Portunus trituberculatus larvas juvenile(Z1,Z2,Z3,Z4 to M)was 81, 120,141,162 and 200 h respectively,and the median lethal time was 39,66,90,64 and 174 h respectively. The displaying time of metamorphosis point was 33,57,69,54 and 150 h respectively under the condition of re-feeding recovering after the short-fasting.When the single fasting time was inside of the displaying time of metamorphosis point,the survival rate and metamorphosis rate were both declined,the larva metamor-phosis time prolonged and the death rate of anomalism was increased as the fasting time extending.There was no difference between the Z1(group of starving for 3 h and the group of the recurring mode of/feeding for 3 h then fasting for 3 h0).The results of Z2,Z2,Z4,M is same as the Z1(Z2 is between the group of fasting for 4 h and the group of recurring mode of/feeding for 4 h then fasting for 4 h0,Z3 is between the group of fasting for 4.5 h and the group of recurring mode of/feeding for 4.5 h then fasting for 4.5 h0, Z4 is between the group of fasting for 6 h and the group of recurring mode of/feeding for 6 h then fasting for 6 h,M is be ween the group of fasting for 7.5 h,fasting 15 h and the group of recurring mode of/feeding for 6 h then fasting for 6 h0).Finally,the thesis discussed the definition of fasting limit value and the total restricted disposing time,and the survival and metamorphosis character under short-period starvation of different period of Portunus trituberculatus larvas.
2007, 29(4): 120-127.
Abstract:
By the continuous sampling in Zhoushan sea area from July 2004 to April 2005,the study as conducted to invest igate the change of gonadosomatic index(GSI),hepatosomatic index(HSI),external features of ovary(size,morphology,color,etc),ovarian histology and its stages during the first reproductive cycle of Portunus trituberculatus.The results indicated that,the reproductive molt of Portunus trituber culatus occurs from September to October,while it spawns from March to April.During the ovarian development,the GSI increases significantly,while the HSI rises slightly,then declines gradually.The negative correlation could be found between GSI and HSI during the period.Based on GSI,HSI,external features of ovary,and histological configuration,the process of ovarian development could be divided into six stages,Ⅰ the ovary is ribbonlike and transparent,the main cells in the ovary are oo gonia(oo)and previt ellogenic oocyte(PR)before reproductive molt;Ⅱ the ovary is milk white,the main cells in the ovary are endogenous vitellogeic oocyte(EN)and PR;Ⅲ the ovary is buff and orange,the main cell type in the ovary is exogenous vitellogenic oocyte(EX);Ⅳ the ovary is deep orange,the main cell types are EX and nearly-mature oocyte(NO)in the ovary;Ⅴ the ovary is ripe,the main cell type is mature oocy te(MO); Ⅵ the crab has spawned,the ovary is light orange,the basal laminas(BL)and follicular cells(FC)could be found in the ovary.
By the continuous sampling in Zhoushan sea area from July 2004 to April 2005,the study as conducted to invest igate the change of gonadosomatic index(GSI),hepatosomatic index(HSI),external features of ovary(size,morphology,color,etc),ovarian histology and its stages during the first reproductive cycle of Portunus trituberculatus.The results indicated that,the reproductive molt of Portunus trituber culatus occurs from September to October,while it spawns from March to April.During the ovarian development,the GSI increases significantly,while the HSI rises slightly,then declines gradually.The negative correlation could be found between GSI and HSI during the period.Based on GSI,HSI,external features of ovary,and histological configuration,the process of ovarian development could be divided into six stages,Ⅰ the ovary is ribbonlike and transparent,the main cells in the ovary are oo gonia(oo)and previt ellogenic oocyte(PR)before reproductive molt;Ⅱ the ovary is milk white,the main cells in the ovary are endogenous vitellogeic oocyte(EN)and PR;Ⅲ the ovary is buff and orange,the main cell type in the ovary is exogenous vitellogenic oocyte(EX);Ⅳ the ovary is deep orange,the main cell types are EX and nearly-mature oocyte(NO)in the ovary;Ⅴ the ovary is ripe,the main cell type is mature oocy te(MO); Ⅵ the crab has spawned,the ovary is light orange,the basal laminas(BL)and follicular cells(FC)could be found in the ovary.
2007, 29(4): 128-136.
Abstract:
On the basis of structural and functional indicat or system and of Analytic Hierarchy Process (AHP),ecosystem health of the sea areas in the Changjiang River Estuary was primarily assessed underlying the ecological survey data in August from 2002 to 2004.The indicator system for ecosystem health assessment of the Changjiang River Estuary can be established by three types of physic-chemical,ecological and scio-economic indicators with 30 indicators.The result showed that the value of integrated health indicator of the Yangtze River Estuary ecosystem(IHIYRE)were 3.09,3.17 and 4.36 in August from 2002 to 2004 respectively,which were lower than systematic health value(5).It showed that,ingeneral,the Changjiang River Estuary ecosystem was located between healthy and unhealthy(3≤IHIYRE≤5).On the situation of pollution,the sea areas in the Changjiang River Estuary are rather seriously eutro phicated and the status is rather stable.Therefore,it needs much endeavors to restore the sea areas to be healthy with lots of material and energy.
On the basis of structural and functional indicat or system and of Analytic Hierarchy Process (AHP),ecosystem health of the sea areas in the Changjiang River Estuary was primarily assessed underlying the ecological survey data in August from 2002 to 2004.The indicator system for ecosystem health assessment of the Changjiang River Estuary can be established by three types of physic-chemical,ecological and scio-economic indicators with 30 indicators.The result showed that the value of integrated health indicator of the Yangtze River Estuary ecosystem(IHIYRE)were 3.09,3.17 and 4.36 in August from 2002 to 2004 respectively,which were lower than systematic health value(5).It showed that,ingeneral,the Changjiang River Estuary ecosystem was located between healthy and unhealthy(3≤IHIYRE≤5).On the situation of pollution,the sea areas in the Changjiang River Estuary are rather seriously eutro phicated and the status is rather stable.Therefore,it needs much endeavors to restore the sea areas to be healthy with lots of material and energy.
2007, 29(4): 137-147.
Abstract:
Anumerical model is developed with a new type of Boussinesq equations employed as the governing equations.In the present numerical model,the seven-point finite difference scheme is used to discretize the spatial derivatives,the fifth-order Runge-Kutta-England scheme is employed to perform the time integration,and the appropriate out flow boundary condition is adopted.Systematic numerical modeling of wave propagation is performed with a uniform depth from shallow to deep water and from linear to nonlinear waves.The calculations show that the results of the present numerical model are basically agreement with those of analytical solutions.An experiment is carried out for wave propagation over a submerged bar with different incident wave parameters.The comparisons between the numerical resolutions and the experimental data are made.
Anumerical model is developed with a new type of Boussinesq equations employed as the governing equations.In the present numerical model,the seven-point finite difference scheme is used to discretize the spatial derivatives,the fifth-order Runge-Kutta-England scheme is employed to perform the time integration,and the appropriate out flow boundary condition is adopted.Systematic numerical modeling of wave propagation is performed with a uniform depth from shallow to deep water and from linear to nonlinear waves.The calculations show that the results of the present numerical model are basically agreement with those of analytical solutions.An experiment is carried out for wave propagation over a submerged bar with different incident wave parameters.The comparisons between the numerical resolutions and the experimental data are made.
2007, 29(4): 148-151.
Abstract:
An mathematical expression of buoyancy frequency profile in some shallow waters is presented. Using resolution of hypergeometric equation,an analytical resolution of internal wave modes equation is obtained such as eigenfunction,frequency dispersion function.The results of an ideal condition ar ediscussed.
An mathematical expression of buoyancy frequency profile in some shallow waters is presented. Using resolution of hypergeometric equation,an analytical resolution of internal wave modes equation is obtained such as eigenfunction,frequency dispersion function.The results of an ideal condition ar ediscussed.
2007, 29(4): 152-155.
Abstract:
2007, 29(4): 156-160.
Abstract:
2007, 29(4): 161-164.
Abstract:
2007, 29(4): 165-169.
Abstract:
2007, 29(4): 170-176.
Abstract:
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