2012 Vol. 34, No. 6
Display Method:
2012, 34(6): 1-10.
Abstract:
Based on 25 h shipboard ADCP measurements across Kemen Channel,time series of tidal currents over 12 sites,which distribute evenly along the transect,were constructed to improve our understanding of tidal characteristics and residuals in this region.The tidal currents in Kemen Channel were identified as the regular semidiurnal and reversing tidal flows,with its behavior more like standing waves.Moreover,the flood currents in the lower layers were found to be ahead of that in the upper layers and vice versa for ebb tides.The major of tidal ellipse for M2 constituent was found to be larger close to the southern side of channel,with its incline also increasing toward the south.The signs of M4 constituent are also found mainly nearby the end points of this transect,indicating the importance of nonlinearity in tidal dynamics due to the shallower topography.A two-layer structure was found for the residual currents in Kemen Channel,flowing northeastwardly out of the bay in upper 20 m with a further south core position and southwestwardly into the bay in the lowers,with a further north core position.Besides approximate 4.81×108 m3 water exchanges were determined between the Luoyuan Bay and outer seas by the calculation of tidal transports through Kemen Channel.
Based on 25 h shipboard ADCP measurements across Kemen Channel,time series of tidal currents over 12 sites,which distribute evenly along the transect,were constructed to improve our understanding of tidal characteristics and residuals in this region.The tidal currents in Kemen Channel were identified as the regular semidiurnal and reversing tidal flows,with its behavior more like standing waves.Moreover,the flood currents in the lower layers were found to be ahead of that in the upper layers and vice versa for ebb tides.The major of tidal ellipse for M2 constituent was found to be larger close to the southern side of channel,with its incline also increasing toward the south.The signs of M4 constituent are also found mainly nearby the end points of this transect,indicating the importance of nonlinearity in tidal dynamics due to the shallower topography.A two-layer structure was found for the residual currents in Kemen Channel,flowing northeastwardly out of the bay in upper 20 m with a further south core position and southwestwardly into the bay in the lowers,with a further north core position.Besides approximate 4.81×108 m3 water exchanges were determined between the Luoyuan Bay and outer seas by the calculation of tidal transports through Kemen Channel.
2012, 34(6): 11-18.
Abstract:
This paper deals the Copula theory and some of common bivariate Archimedean Copula properties and suitability. A case study is given by using yearly maximum surge heights and corresponding wind speeds collected at Mayu gauge in Shantou sea waters of eastern Guangdong. Bivariate joint distribution model is built up through optimized two marginal distribution of yearly maximum surge heights and corresponding wind speeds by using goodness-of-fit test among three tri-parameter probability distribution model including Generalized extreme value distribution,Pearson pattern three and Weibull distribution. Some conclusions were reached in the following: (1) Optimized marginal distributions of yearly maximum surge heights and corresponding wind speeds can be represented by the Weibull distribution and Pearson pattern three distribution, respectively;(2) Gumbel-Hougaard Copula that belongs to Archimedean copula family is the optimal copula selected by the goodness-of-fit test;(3) Compare to the joint distribution,the relative differences of the special frequency design values of the marginal distribution of yearly maximum surge heights fall in between 6.7% and 22.2% for the return periods between 2 and 200 year;(4) The encounter probabilities of yearly maximum surge heights given wind velocity rapidly decrease along with the minishing design frequency of surge heights;whereas the encounter probabilities increase when the specific surge height frequency along with decrease of wind velocity frequency.
This paper deals the Copula theory and some of common bivariate Archimedean Copula properties and suitability. A case study is given by using yearly maximum surge heights and corresponding wind speeds collected at Mayu gauge in Shantou sea waters of eastern Guangdong. Bivariate joint distribution model is built up through optimized two marginal distribution of yearly maximum surge heights and corresponding wind speeds by using goodness-of-fit test among three tri-parameter probability distribution model including Generalized extreme value distribution,Pearson pattern three and Weibull distribution. Some conclusions were reached in the following: (1) Optimized marginal distributions of yearly maximum surge heights and corresponding wind speeds can be represented by the Weibull distribution and Pearson pattern three distribution, respectively;(2) Gumbel-Hougaard Copula that belongs to Archimedean copula family is the optimal copula selected by the goodness-of-fit test;(3) Compare to the joint distribution,the relative differences of the special frequency design values of the marginal distribution of yearly maximum surge heights fall in between 6.7% and 22.2% for the return periods between 2 and 200 year;(4) The encounter probabilities of yearly maximum surge heights given wind velocity rapidly decrease along with the minishing design frequency of surge heights;whereas the encounter probabilities increase when the specific surge height frequency along with decrease of wind velocity frequency.
2012, 34(6): 19-29.
Abstract:
In Greenland sea,the convection produced by isopycnal cabbeling is an important type of convection. The Arctic Ocean is experiencing intense and rapid changes, in which the changes of water masses and circulation system will alter isopycnal cabbeling convection of Greenland Sea, and further affect the Global climate system. Previous researches on isopycnal cabbeling convection are few, most of them focus on convective regions. As in Greenland Sea,Recirculating Atlantic Water and water masses from Arctic Ocean are the main water masses that involved in the cabbeling convection, so the purpose of this paper is to discuss the possible effects of various water masses in different regions of Arctic Ocean to Greenland Sea cabbeling convection. In this paper, effective cabbeling convection velocity is defined. It's emphasized that horizontal temperature gradient and vertical stratification intensit is determinant to cabbeling velocity. And greater temperature gradient and weaker stratification intensity will lead to intenser convection. In Greenland sea, various water masses involved in the isopycnal cabbeling convection all originate from Atlantic Ocean. Some of them are Recirculating Atlantic Water recirculating in Greenland Sea, the others are Atlantic Water of Arctic which experience recirculating and diving in Arctic Ocean. If the later water masses stay in the Arctic Ocean longer, the temperature gradient will be greater, and the convection will be intenser. While, the water masses from Pacific Ocean which cross the Arctic Ocean could not be involved in isopycnal cabbeling convection for its low density. In the Arctic Mediterranean, deep-water temperature varies between the different basins, so these deep water masses may produce Effective Cabbeling Convection through mixing with Greenland Sea Deep Water. But in the deep and bottom layer of ocean, the current velocity is low, turbulent mixing is weak and temperature gradiant is small, so at present it's not sure whether the convection exists.
In Greenland sea,the convection produced by isopycnal cabbeling is an important type of convection. The Arctic Ocean is experiencing intense and rapid changes, in which the changes of water masses and circulation system will alter isopycnal cabbeling convection of Greenland Sea, and further affect the Global climate system. Previous researches on isopycnal cabbeling convection are few, most of them focus on convective regions. As in Greenland Sea,Recirculating Atlantic Water and water masses from Arctic Ocean are the main water masses that involved in the cabbeling convection, so the purpose of this paper is to discuss the possible effects of various water masses in different regions of Arctic Ocean to Greenland Sea cabbeling convection. In this paper, effective cabbeling convection velocity is defined. It's emphasized that horizontal temperature gradient and vertical stratification intensit is determinant to cabbeling velocity. And greater temperature gradient and weaker stratification intensity will lead to intenser convection. In Greenland sea, various water masses involved in the isopycnal cabbeling convection all originate from Atlantic Ocean. Some of them are Recirculating Atlantic Water recirculating in Greenland Sea, the others are Atlantic Water of Arctic which experience recirculating and diving in Arctic Ocean. If the later water masses stay in the Arctic Ocean longer, the temperature gradient will be greater, and the convection will be intenser. While, the water masses from Pacific Ocean which cross the Arctic Ocean could not be involved in isopycnal cabbeling convection for its low density. In the Arctic Mediterranean, deep-water temperature varies between the different basins, so these deep water masses may produce Effective Cabbeling Convection through mixing with Greenland Sea Deep Water. But in the deep and bottom layer of ocean, the current velocity is low, turbulent mixing is weak and temperature gradiant is small, so at present it's not sure whether the convection exists.
2012, 34(6): 30-41.
Abstract:
A three dimensional tide and tidal current system was established using unstructured triangular grids for Jiaozhou Bay,based on a Finite-Volume Coastal Ocean Model (FVCOM).With five different sets of coastlines and water depths in different decades,we compared the hydrodynamic changes of Jiaozhou Bay including tidal prism,tide and tidal currents as well as water exchange rate.The model results show that the tidal prism decreases gradually with the reducing of the water area of Jiaozhou Bay.To be more specific,the tidal prism in 2008 reduces by 31.5% compared with that in 1935,which is about 3.9×108m3.The patterns of velocity fields in different decades are similar,however the velocity decreases.The multi-vortex pattern of the Eulerian residual currents remains with small changes of their positions and sizes.The strongest Eulerian residual current normally appears near Tuandao.The general trend of water exchange capacity is decreasing.The averaged half-exchange time is 37.0,36.7,39.2,39.7,40.8 d in 1935,1966,1986,2000 and 2008,respectively.
A three dimensional tide and tidal current system was established using unstructured triangular grids for Jiaozhou Bay,based on a Finite-Volume Coastal Ocean Model (FVCOM).With five different sets of coastlines and water depths in different decades,we compared the hydrodynamic changes of Jiaozhou Bay including tidal prism,tide and tidal currents as well as water exchange rate.The model results show that the tidal prism decreases gradually with the reducing of the water area of Jiaozhou Bay.To be more specific,the tidal prism in 2008 reduces by 31.5% compared with that in 1935,which is about 3.9×108m3.The patterns of velocity fields in different decades are similar,however the velocity decreases.The multi-vortex pattern of the Eulerian residual currents remains with small changes of their positions and sizes.The strongest Eulerian residual current normally appears near Tuandao.The general trend of water exchange capacity is decreasing.The averaged half-exchange time is 37.0,36.7,39.2,39.7,40.8 d in 1935,1966,1986,2000 and 2008,respectively.
2012, 34(6): 42-49.
Abstract:
Based on the ocean temperature reanalysis data of Ishii etc,this paper discusses the seasonal and interannual variability of upwelling region in southwestern tropical India Ocean(SWTIO),the temperature anomalies related to the upwelling region,and the relationship between the variations and tropical India and Pacific Ocean air-sea system. The study shows that the upwelling in SWTIO is the strongest in summer and winter and weakest in spring in the southern hemisphere. The scope extends 5°-10°S from north to south and 50°-90°E from west to east. The variations of the upwelling region are closely related to the temperature anomalies on the thermocline and there is an outstanding 5 a oscillation cycle. The oscillation propagates along the path of 11.5°-6.5°S to the west on the vertical maximum temperature anomaly level(MTAL) from eastern tropical India Ocean. The propagation is different from the temperature anomalies propagation in tropical Pacific Ocean. The SWTIO upwelling is an important component of the air-sea interaction system of India-Pacific Ocean. The India Ocean DIPOLE index is 5 months ahead of the temperature changes of the SWTIO upwelling region and the maximum correlation coefficient reaches 0.57. The NINO3 SST index is 2 months ahead of the temperature changes of the SWTIO upwelling region and the correlation coefficient reaches 0.49. The changes of wind field above tropical Indian-Pacific Ocean impact the changes of SSTA on the surface of tropical Pacific and India Ocean,leading to the cycle of ENSO and DIPOLE and further triggering the changes in the upwelling region of SWTIO.
Based on the ocean temperature reanalysis data of Ishii etc,this paper discusses the seasonal and interannual variability of upwelling region in southwestern tropical India Ocean(SWTIO),the temperature anomalies related to the upwelling region,and the relationship between the variations and tropical India and Pacific Ocean air-sea system. The study shows that the upwelling in SWTIO is the strongest in summer and winter and weakest in spring in the southern hemisphere. The scope extends 5°-10°S from north to south and 50°-90°E from west to east. The variations of the upwelling region are closely related to the temperature anomalies on the thermocline and there is an outstanding 5 a oscillation cycle. The oscillation propagates along the path of 11.5°-6.5°S to the west on the vertical maximum temperature anomaly level(MTAL) from eastern tropical India Ocean. The propagation is different from the temperature anomalies propagation in tropical Pacific Ocean. The SWTIO upwelling is an important component of the air-sea interaction system of India-Pacific Ocean. The India Ocean DIPOLE index is 5 months ahead of the temperature changes of the SWTIO upwelling region and the maximum correlation coefficient reaches 0.57. The NINO3 SST index is 2 months ahead of the temperature changes of the SWTIO upwelling region and the correlation coefficient reaches 0.49. The changes of wind field above tropical Indian-Pacific Ocean impact the changes of SSTA on the surface of tropical Pacific and India Ocean,leading to the cycle of ENSO and DIPOLE and further triggering the changes in the upwelling region of SWTIO.
2012, 34(6): 50-58.
Abstract:
Sea surface roughness derived from dimensional analysis bears a relation to wave age and swell. The paper explored two scalings parameterization schemes' sensitivity to wave age and wave steepness, concluded that the errors estimated from wave age scaling are lower from wave steepness scaling. Based on data of the six air-sea interaction experiments under different water depth, fetch and sea state conditions, we distinguished between two classes of sea state: pure wind sea or wind sea-dominant and swell-dominant,tested the suitability of the wave age and wave steepness scalings schemes under different experiments. It be found that wave age scaling have higher suitability than wave steepness scaling under variedly sea state conditions. For pure wind sea or wind sea-dominant cases, the calculated results based on PS07 and DGHQ03 are close to those given by the eddy correlation method, GW06 scheme secondly, O02 calculations are overestimated markedly. For swell-dominated sea cases the calculated results based on the two sea-state scalings are all underestimated. The errors of sea roughness based on O02 scheme is the least, the TY01 scheme lead to the maximum errors.
Sea surface roughness derived from dimensional analysis bears a relation to wave age and swell. The paper explored two scalings parameterization schemes' sensitivity to wave age and wave steepness, concluded that the errors estimated from wave age scaling are lower from wave steepness scaling. Based on data of the six air-sea interaction experiments under different water depth, fetch and sea state conditions, we distinguished between two classes of sea state: pure wind sea or wind sea-dominant and swell-dominant,tested the suitability of the wave age and wave steepness scalings schemes under different experiments. It be found that wave age scaling have higher suitability than wave steepness scaling under variedly sea state conditions. For pure wind sea or wind sea-dominant cases, the calculated results based on PS07 and DGHQ03 are close to those given by the eddy correlation method, GW06 scheme secondly, O02 calculations are overestimated markedly. For swell-dominated sea cases the calculated results based on the two sea-state scalings are all underestimated. The errors of sea roughness based on O02 scheme is the least, the TY01 scheme lead to the maximum errors.
2012, 34(6): 59-65.
Abstract:
A massive Mw 9.0 earthquake occurred on 11 March 2011, off the Pacific coast of the east of Miyagi, Japan. The earthquake caused severe surface dislocations and launched a tsunami. In this paper, our developed software UniP, based on the precise point positioning mode, is used to extract the co-seismic and post-seismic surface movement information from IGS data and Chinese coastal GPS data.The results show: (1) The co-seismic surface deformation processes are clearly recorded by the GPS kinematic positioning results, and these elastic deformation on CHAN and NCST sites is up to 15 cm. (2) The massive earthquake did not cause obvious permanent position shift of GPS sites in China, because of distant range. The maximum eastward shift on CHAN is(1.8±0.11)cm. (3) The travel time is almost 10 minutes for seismic wave to NCST and NLHT site. The propagation velocity of seismic wave is about 14 times faster than that of tsunami. So the arrival time difference may be enough for the tsunami prediction. These results reveal that GPS technology can provide valuable basic data for earthquake monitoring and dynamic characteristics. It further demonstrates the application potential of Chinese Coastal GPS monitoring system in seaquake monitoring and tsunami warning services.
A massive Mw 9.0 earthquake occurred on 11 March 2011, off the Pacific coast of the east of Miyagi, Japan. The earthquake caused severe surface dislocations and launched a tsunami. In this paper, our developed software UniP, based on the precise point positioning mode, is used to extract the co-seismic and post-seismic surface movement information from IGS data and Chinese coastal GPS data.The results show: (1) The co-seismic surface deformation processes are clearly recorded by the GPS kinematic positioning results, and these elastic deformation on CHAN and NCST sites is up to 15 cm. (2) The massive earthquake did not cause obvious permanent position shift of GPS sites in China, because of distant range. The maximum eastward shift on CHAN is(1.8±0.11)cm. (3) The travel time is almost 10 minutes for seismic wave to NCST and NLHT site. The propagation velocity of seismic wave is about 14 times faster than that of tsunami. So the arrival time difference may be enough for the tsunami prediction. These results reveal that GPS technology can provide valuable basic data for earthquake monitoring and dynamic characteristics. It further demonstrates the application potential of Chinese Coastal GPS monitoring system in seaquake monitoring and tsunami warning services.
2012, 34(6): 66-73.
Abstract:
Based on the multi-satellite altimeter data in orbit, which include Jason-2 data since its successful launch(cycle 001-113), Envisat data(cycle 070-107,cross the track adjusted periods) and Jason-1 data after the track adjusted (cycle 263-352), these altimeter data are analyzed and validated cycle by cycle to eliminate the exceptional data cycle after ionosphere correction smoothing, geophysical correcting and data editing. Then the effects of time variation and radial orbit error in the altimetry data are weakened by the collinear process and crossover adjustment. After the unification of reference ellipsoid and reference frame, a 2'×2' resolution mean sea surface model over China sea and its adjacent sea areas(0°-45°N, 100°-140°E) is obtained by Shepard method. Finally, the presented mean sea surface model is compared with MSS_CNES_CLS01 and MSS_CNES_CLS10 model, and the root-mean-square values are 8.28 cm and 11.65 cm respectively. This proves that the new mean sea surface model is correct.
Based on the multi-satellite altimeter data in orbit, which include Jason-2 data since its successful launch(cycle 001-113), Envisat data(cycle 070-107,cross the track adjusted periods) and Jason-1 data after the track adjusted (cycle 263-352), these altimeter data are analyzed and validated cycle by cycle to eliminate the exceptional data cycle after ionosphere correction smoothing, geophysical correcting and data editing. Then the effects of time variation and radial orbit error in the altimetry data are weakened by the collinear process and crossover adjustment. After the unification of reference ellipsoid and reference frame, a 2'×2' resolution mean sea surface model over China sea and its adjacent sea areas(0°-45°N, 100°-140°E) is obtained by Shepard method. Finally, the presented mean sea surface model is compared with MSS_CNES_CLS01 and MSS_CNES_CLS10 model, and the root-mean-square values are 8.28 cm and 11.65 cm respectively. This proves that the new mean sea surface model is correct.
2012, 34(6): 74-83.
Abstract:
Using the marine sediment samples collected from the middle western area of the southern Huanghai Sea, the experimental study on sediment acoustic properties and their influencing factors was conducted. The experimental results show that the compressional wave speeds range from 1.359 to 1.695 km/s, and the shear wave speeds range between 12.5 and 70.9 m/s; the finer grained sediment, which is distributed mainly over the east side of study area where the water depth is deeper, corresponds to the lower compressional wave speed and the shear wave speed; the sediment physical-mechanical properties have a great influence on the compressional wave speed and the shear wave speed, and the sediment temperature and the transducer frequency have a definite effect on the compressional and shear wave speeds; the sediment heterogeneity such as layering or inclusions influences the calculation accuracy of wave propagation models. The regressions among sediment physical-mechanical properties and acoustic properties are given in order to provide basic information for national defence and engineering construction.
Using the marine sediment samples collected from the middle western area of the southern Huanghai Sea, the experimental study on sediment acoustic properties and their influencing factors was conducted. The experimental results show that the compressional wave speeds range from 1.359 to 1.695 km/s, and the shear wave speeds range between 12.5 and 70.9 m/s; the finer grained sediment, which is distributed mainly over the east side of study area where the water depth is deeper, corresponds to the lower compressional wave speed and the shear wave speed; the sediment physical-mechanical properties have a great influence on the compressional wave speed and the shear wave speed, and the sediment temperature and the transducer frequency have a definite effect on the compressional and shear wave speeds; the sediment heterogeneity such as layering or inclusions influences the calculation accuracy of wave propagation models. The regressions among sediment physical-mechanical properties and acoustic properties are given in order to provide basic information for national defence and engineering construction.
2012, 34(6): 84-93.
Abstract:
The spectral signal of sediment on intertidal flats is easily concealed as the result of high moisture inside,which is the main obstacle for retrieving sediment types by means of remote sensing technology.To improve the accuracy of quantifying sediment characteristics,the effects of varying moisture must be removed.With the use of in situ samples of sediment collected in Dafeng,Jiangsu Province,China and its spectra measured under different moisture conditions in the laboratory,a linear spectral unmixing technology is employed to obtain moisture abundance and analyze the spectral response of sediment to varied moisture content.The moisture content layer of study area retrieved by a linear regression techniology on Hyperion image is introduced as variable into multiple variable linear regression equations.The models,which can eliminate the moisture impact,are constructed and applied in Hyperion image to retrieve components'(sand,silt and clay) spatial distribution.Retrieved components are input to Shepard classification system to map the sediment types of intertidal flats automatically.The results are shown as below:(1)the spectral contribution from water is dominant while the moisture content is higher than 25% and its value increases two times with the rate of moisture content increasing;(2) the reflectance of samples in 2 143 nm is sensitive to the variation of moisture,and square (r2) of correlation coefficient of constructed moisture model is 0.81;(3)the reflectance of samples in 983 and 1 134 nm is sensitive to the content of each component,these two bands combined moisture sensitive band are utilized to construct the multiple variable linear regression equation,which can effectively remove the moisture impact on wet samples;(4)the overall classification accuracy is 75.93%,and Kappa coefficient reaches 0.60.This method is an effective way to map the spatial distribution characteristic of sediment types accurately on muddy intertidal flats.
The spectral signal of sediment on intertidal flats is easily concealed as the result of high moisture inside,which is the main obstacle for retrieving sediment types by means of remote sensing technology.To improve the accuracy of quantifying sediment characteristics,the effects of varying moisture must be removed.With the use of in situ samples of sediment collected in Dafeng,Jiangsu Province,China and its spectra measured under different moisture conditions in the laboratory,a linear spectral unmixing technology is employed to obtain moisture abundance and analyze the spectral response of sediment to varied moisture content.The moisture content layer of study area retrieved by a linear regression techniology on Hyperion image is introduced as variable into multiple variable linear regression equations.The models,which can eliminate the moisture impact,are constructed and applied in Hyperion image to retrieve components'(sand,silt and clay) spatial distribution.Retrieved components are input to Shepard classification system to map the sediment types of intertidal flats automatically.The results are shown as below:(1)the spectral contribution from water is dominant while the moisture content is higher than 25% and its value increases two times with the rate of moisture content increasing;(2) the reflectance of samples in 2 143 nm is sensitive to the variation of moisture,and square (r2) of correlation coefficient of constructed moisture model is 0.81;(3)the reflectance of samples in 983 and 1 134 nm is sensitive to the content of each component,these two bands combined moisture sensitive band are utilized to construct the multiple variable linear regression equation,which can effectively remove the moisture impact on wet samples;(4)the overall classification accuracy is 75.93%,and Kappa coefficient reaches 0.60.This method is an effective way to map the spatial distribution characteristic of sediment types accurately on muddy intertidal flats.
2012, 34(6): 94-101.
Abstract:
The field observation was carried out in Febuary 2010 to March 2010. A total of 39 stations was established three transects. Based on the data collected, the composition and distribution of dissolved inorganic carbon(DIC) were examined in 0 m, 10 m, 30 m depth and H Section. The results showed that the concentration of DIC and it's parameters in each depth were similar. The concentration of DIC and HCO3- decreasing from southwest to northeast. Temperature has important influence on the distribution of DIC and HCO3-. The relationship between p(CO2) and chlorophyll-a was negative. In H section, the distribution of DIC and it's parameters of middle section were more complicated than the other section. The CO2 flux at the Bohai Strait was 3.52 mmol/(m2·d), which shows that this area was the source of CO2 in winter. The DIC flux flowed from the Bohai Strait was (130±2)×103 mol/s.
The field observation was carried out in Febuary 2010 to March 2010. A total of 39 stations was established three transects. Based on the data collected, the composition and distribution of dissolved inorganic carbon(DIC) were examined in 0 m, 10 m, 30 m depth and H Section. The results showed that the concentration of DIC and it's parameters in each depth were similar. The concentration of DIC and HCO3- decreasing from southwest to northeast. Temperature has important influence on the distribution of DIC and HCO3-. The relationship between p(CO2) and chlorophyll-a was negative. In H section, the distribution of DIC and it's parameters of middle section were more complicated than the other section. The CO2 flux at the Bohai Strait was 3.52 mmol/(m2·d), which shows that this area was the source of CO2 in winter. The DIC flux flowed from the Bohai Strait was (130±2)×103 mol/s.
2012, 34(6): 102-113.
Abstract:
Twenty eight surface sediment samples were collected from the Kongsfjorden (Svalbard) in Arctic Area. We measured the molecular weight distribution, UV-Visible absorbance spectrum and three-dimensional fluorescence spectrum of water soluble organic matter (also named dissolved organic matter, DOM) in the sediment. Moreover, the fluorescence components and sources of DOM were resolved by using parallel factor analysis (PARAFAC). It was showed that the contents of chromatophoric DOM (CDOM) and fluorescent DOM (FDOM) had a tendency to accumulate gradually from the head to the mouth in this arctic fjord. But the ratio of FDOM to CDOM decreased gradually, which is closely related to the aging process of sediment DOM. It is mainly due to the long-term photodegradation and biodegradation, and the weakening sedimentation, which also contributes to the accumulation of humic substances and small molecules. FDOM in the sediment comprised three fluorescent components including terrestrial humic-like material, autochthonous humic-like and protein-like material. The spectral slope ratio (SR) decreased with the increase of the percentage of autochthonous DOM while it increased with the increase of the ratio of terrestrial DOM to autochthonous DOM. The humification index (HIX) increased with the increase of humic-like to protein-like ratio and water depth while the biological origin index (BIX) increased with the autochthonous percentage increasing. Large spatial variability of the composition and sources of sedimentary organic matter was found in this fjord. In the glacial bay area, sediment DOM mainly came from the newly transport and transformation of particulate organic matter (POM) in the water column; in the center and mouth of the fjord, sediment DOM was dominated by old humic substances, which originate from the long-term of transport and transformation of DOM in the water column. The spectral fingerprint of CDOM acts as a proxy for revealing the origins and transformation history of dissolved organic matter in the sediment. It is significant for exploring the evolution of fjord environment under the interaction of ocean and glacier.
Twenty eight surface sediment samples were collected from the Kongsfjorden (Svalbard) in Arctic Area. We measured the molecular weight distribution, UV-Visible absorbance spectrum and three-dimensional fluorescence spectrum of water soluble organic matter (also named dissolved organic matter, DOM) in the sediment. Moreover, the fluorescence components and sources of DOM were resolved by using parallel factor analysis (PARAFAC). It was showed that the contents of chromatophoric DOM (CDOM) and fluorescent DOM (FDOM) had a tendency to accumulate gradually from the head to the mouth in this arctic fjord. But the ratio of FDOM to CDOM decreased gradually, which is closely related to the aging process of sediment DOM. It is mainly due to the long-term photodegradation and biodegradation, and the weakening sedimentation, which also contributes to the accumulation of humic substances and small molecules. FDOM in the sediment comprised three fluorescent components including terrestrial humic-like material, autochthonous humic-like and protein-like material. The spectral slope ratio (SR) decreased with the increase of the percentage of autochthonous DOM while it increased with the increase of the ratio of terrestrial DOM to autochthonous DOM. The humification index (HIX) increased with the increase of humic-like to protein-like ratio and water depth while the biological origin index (BIX) increased with the autochthonous percentage increasing. Large spatial variability of the composition and sources of sedimentary organic matter was found in this fjord. In the glacial bay area, sediment DOM mainly came from the newly transport and transformation of particulate organic matter (POM) in the water column; in the center and mouth of the fjord, sediment DOM was dominated by old humic substances, which originate from the long-term of transport and transformation of DOM in the water column. The spectral fingerprint of CDOM acts as a proxy for revealing the origins and transformation history of dissolved organic matter in the sediment. It is significant for exploring the evolution of fjord environment under the interaction of ocean and glacier.
2012, 34(6): 114-125.
Abstract:
The heavy mineral assemblages and grain-size compositions of 360 surface sediment samples on the northeast shelf of the East China Sea are analyzed for the study of depositional environments. An R-type cluster analysis suggests that stable minerals or opaque minerals and a heavy mineral differentiation index can discriminate the distribution patterns of detrital minerals on the shelf. Meanwhile,a K-means cluster analysis can identify three groups: relict sandy area, subaqueous prodelta of the Changjiang River and muddy belt on the inner shelf off Zhejiang and Fujiang Provinces, and the Changjiang sand sheet area. The combination of grain size, heavy minerals, 14C age and sedimentation environment primarily determines the formation of relict/reworked sediments on the mid-outer shelf and the mud distribution in the Fujian-Zhejiang coast, and sediment source to sink transport during the postglacial transgression.The results of cluster analysis clearly reveal the relation between detrital mineral compositions and hydrodynamic sorting of single-provenance sediment. However, it may cause some misleading results when complex sources exist. The surface sediments of the Changjiang tidal sand sheet are reworked tidal sand ridges with formation ages of 6~4 and 3~2 ka B.P.
The heavy mineral assemblages and grain-size compositions of 360 surface sediment samples on the northeast shelf of the East China Sea are analyzed for the study of depositional environments. An R-type cluster analysis suggests that stable minerals or opaque minerals and a heavy mineral differentiation index can discriminate the distribution patterns of detrital minerals on the shelf. Meanwhile,a K-means cluster analysis can identify three groups: relict sandy area, subaqueous prodelta of the Changjiang River and muddy belt on the inner shelf off Zhejiang and Fujiang Provinces, and the Changjiang sand sheet area. The combination of grain size, heavy minerals, 14C age and sedimentation environment primarily determines the formation of relict/reworked sediments on the mid-outer shelf and the mud distribution in the Fujian-Zhejiang coast, and sediment source to sink transport during the postglacial transgression.The results of cluster analysis clearly reveal the relation between detrital mineral compositions and hydrodynamic sorting of single-provenance sediment. However, it may cause some misleading results when complex sources exist. The surface sediments of the Changjiang tidal sand sheet are reworked tidal sand ridges with formation ages of 6~4 and 3~2 ka B.P.
2012, 34(6): 126-132.
Abstract:
Tidal creeks are important and distinctive features of coastal environments as they represent a basic circulatory system through which water,sediments,organic matter,nutrients and pollutants are transported into and out of intertidal wetlands. Based on the simplified Poisson hydrodynamic model,a procedure is compiled to achieve the watershed delineation for every subnetwork and drainage scaling properties extraction in the tidal basin of Upper Jiuduansha in Changjiang Estuary. To summarize the calculated and statistical results,two different evolution patterns are defined. The "concentration pattern" is characterized by a single,strong-developed network with alarger drainage area,developing under stronger hydrodynamic conditions,while the "scattering pattern" is represented by several small-scale networks and a smaller drainage area. In the two patterns,tidal channels stretch linearly with the increasing drainage area,which is consistent with the nearly same degree of channelization within the study area.
Tidal creeks are important and distinctive features of coastal environments as they represent a basic circulatory system through which water,sediments,organic matter,nutrients and pollutants are transported into and out of intertidal wetlands. Based on the simplified Poisson hydrodynamic model,a procedure is compiled to achieve the watershed delineation for every subnetwork and drainage scaling properties extraction in the tidal basin of Upper Jiuduansha in Changjiang Estuary. To summarize the calculated and statistical results,two different evolution patterns are defined. The "concentration pattern" is characterized by a single,strong-developed network with alarger drainage area,developing under stronger hydrodynamic conditions,while the "scattering pattern" is represented by several small-scale networks and a smaller drainage area. In the two patterns,tidal channels stretch linearly with the increasing drainage area,which is consistent with the nearly same degree of channelization within the study area.
2012, 34(6): 133-141.
Abstract:
By analyzing drilling cores in gullies which are located in the Lidi Villiage, the northern Dagu Mountain, the Liaodong Peninsula, the results show that the conductivity, diatom analysis results and pH of the clay turbidity water were in the main accordance with the conductivity curve and the salty water diatom curve of the clay turbidity water. By combining the result of diatoms with the conductivity and the pH value of clay, the plain-LD-core is divided into four zones: the Ⅰ zone is the drowned marine-layer in the Holocene transgression, the Ⅱ zone is the intertidal environment which is affected gradually by seawater, the Ⅲ zone is divided into two subzone, they are Ⅲ-1 zone (salt marsh wetlands) and Ⅲ-2 zone(fresh water lake ) respectively. the same to the Ⅳ zone, the Ⅳ-1 zone is a certain depth of the swamp wetland which is not affected by seawater. but the Ⅳ-2 zone is a swamp wetland which is affected by water. The results show that the good consistency between diatom analysis and clay muddy water can be as an important means for distinguishing land facies and sea facies, in addition, the conductivity curve of the clay turbidity water is in good negative correlation with pH, which shows that the conductivity curve of the clay turbidity water is in good accordance with diatom analysis results and they can be used as mutual verification.
By analyzing drilling cores in gullies which are located in the Lidi Villiage, the northern Dagu Mountain, the Liaodong Peninsula, the results show that the conductivity, diatom analysis results and pH of the clay turbidity water were in the main accordance with the conductivity curve and the salty water diatom curve of the clay turbidity water. By combining the result of diatoms with the conductivity and the pH value of clay, the plain-LD-core is divided into four zones: the Ⅰ zone is the drowned marine-layer in the Holocene transgression, the Ⅱ zone is the intertidal environment which is affected gradually by seawater, the Ⅲ zone is divided into two subzone, they are Ⅲ-1 zone (salt marsh wetlands) and Ⅲ-2 zone(fresh water lake ) respectively. the same to the Ⅳ zone, the Ⅳ-1 zone is a certain depth of the swamp wetland which is not affected by seawater. but the Ⅳ-2 zone is a swamp wetland which is affected by water. The results show that the good consistency between diatom analysis and clay muddy water can be as an important means for distinguishing land facies and sea facies, in addition, the conductivity curve of the clay turbidity water is in good negative correlation with pH, which shows that the conductivity curve of the clay turbidity water is in good accordance with diatom analysis results and they can be used as mutual verification.
2012, 34(6): 142-150.
Abstract:
In order to understand the developmental effects and mode of actions of marine fish embryos exposed to three-to five-ring PAH, the ovo EROD activity, heart elongation, hatch rate and heartbeat were measured after the individual exposure of phenanthrene (Phe), pyrene (Py) and benzo(a)pyrene (BaP) and co-exposure each of them with α-naphthoflavone (ANF) for marine medaka (Oryzias melastigma) embryos. Results showed that the rank order in the potency for causing ovo EROD activity induction in marine medaka embryos was BaP>Py>Phe. The relationships between EROD induction and embryo development deformity in each individual exposure of Phe, Py and BaP were very complex, a significant correlated with ovo EROD and deformity index was observed only in Phe(r=0.95,p=0.015). Embryos co-exposed to 100 μg/L ANF with each of each of Phe, Py and BaP were increased in the severity of deformities and were decreased in the hatch rates compared with embryos exposed to PAH individual. The combination effects of each PAH with ANF showed potential synergistic effects. These results demonstrated that there may be different mode of actions on the developmental toxicity effects of marine medaka embryos exposed to three-to five-ring PAH, CYP1A activity inhibited by ANF would not effectively alleviate the embryonic development toxicity on marine medada exposed to PAH. There may be a potential synergistic effect on the toxicity in marine fish embryos co-exposed to CYP1A inhibitor and PAH-type CYP1A inducer, and the current PAH mixture risk assessment model may underestimate their toxicity, particularly of mixtures containing both CYP1A inducers and inhibitors. Heart deformities found to be the most sensitive endpoint in early life stage of marine medaka were recommended as a biomarker to indicate the pollution of PAHs or oil spill in field study.
In order to understand the developmental effects and mode of actions of marine fish embryos exposed to three-to five-ring PAH, the ovo EROD activity, heart elongation, hatch rate and heartbeat were measured after the individual exposure of phenanthrene (Phe), pyrene (Py) and benzo(a)pyrene (BaP) and co-exposure each of them with α-naphthoflavone (ANF) for marine medaka (Oryzias melastigma) embryos. Results showed that the rank order in the potency for causing ovo EROD activity induction in marine medaka embryos was BaP>Py>Phe. The relationships between EROD induction and embryo development deformity in each individual exposure of Phe, Py and BaP were very complex, a significant correlated with ovo EROD and deformity index was observed only in Phe(r=0.95,p=0.015). Embryos co-exposed to 100 μg/L ANF with each of each of Phe, Py and BaP were increased in the severity of deformities and were decreased in the hatch rates compared with embryos exposed to PAH individual. The combination effects of each PAH with ANF showed potential synergistic effects. These results demonstrated that there may be different mode of actions on the developmental toxicity effects of marine medaka embryos exposed to three-to five-ring PAH, CYP1A activity inhibited by ANF would not effectively alleviate the embryonic development toxicity on marine medada exposed to PAH. There may be a potential synergistic effect on the toxicity in marine fish embryos co-exposed to CYP1A inhibitor and PAH-type CYP1A inducer, and the current PAH mixture risk assessment model may underestimate their toxicity, particularly of mixtures containing both CYP1A inducers and inhibitors. Heart deformities found to be the most sensitive endpoint in early life stage of marine medaka were recommended as a biomarker to indicate the pollution of PAHs or oil spill in field study.
2012, 34(6): 151-159.
Abstract:
To evaluate the seasonal distribution of macrozoobenthos and its relationship with environmental factors in the Hangzhou Bay, four cruise surveys were carried out in summer, winter, spring and autumn during 2006-2007. A total of 113 species were identified with the dominant groups of polychaetes, mollusks and crustaceas. Aglaophamus dibranchis, Amaeana occidentalis and Nephtys polybranchia were the dominant species in this area. Based on the results of analysis of variance, no significant seasonal differences were found in community parameters except for the crustacea density. Both the Bray-Curtis similarity analysis and non-metric multidimensional scaling analysis showed no obvious differences of community composition were observed in the Bay. Indicating a relatively simple macrobenthic community feature. The abundance/biomass curves showed that macrobenthic communities were disturbed in autumn. The canonical correspondence analysis showed that the polychate was mainly affected by the physical variables, while mollusk, crustacea and other taxa were mostly influenced by the biological and chemical parameters were the main factors influencing. The result of CCA also could inferred that the macrobenthos in the Hangzhou Bay were primarily influenced by the natural environment features, rather than the human activities.
To evaluate the seasonal distribution of macrozoobenthos and its relationship with environmental factors in the Hangzhou Bay, four cruise surveys were carried out in summer, winter, spring and autumn during 2006-2007. A total of 113 species were identified with the dominant groups of polychaetes, mollusks and crustaceas. Aglaophamus dibranchis, Amaeana occidentalis and Nephtys polybranchia were the dominant species in this area. Based on the results of analysis of variance, no significant seasonal differences were found in community parameters except for the crustacea density. Both the Bray-Curtis similarity analysis and non-metric multidimensional scaling analysis showed no obvious differences of community composition were observed in the Bay. Indicating a relatively simple macrobenthic community feature. The abundance/biomass curves showed that macrobenthic communities were disturbed in autumn. The canonical correspondence analysis showed that the polychate was mainly affected by the physical variables, while mollusk, crustacea and other taxa were mostly influenced by the biological and chemical parameters were the main factors influencing. The result of CCA also could inferred that the macrobenthos in the Hangzhou Bay were primarily influenced by the natural environment features, rather than the human activities.
2012, 34(6): 160-169.
Abstract:
The investigation of marine fouling assemblages on a series of artificial test panels in Dongshan Bay was conducted from September 2008 to August 2009. A total of 102 species were identified and dominated by Ulva fasciata,Pennaria disticha,Haliplanella luciae,Saccostrea cucullata,Brachidontes variabilis,Amphibalanus reticulates,Podocerus brasiliensis,Elasmopus pecteniclus,Stenothoe valida,Caprella equilibra and Sinoflustra amoyensis etc. The fouling organisms were mainly composed of coastal and warm water affinities and the settlements occurred throughout the year,particularly from April to October. The average biomass on the monthly test panels was 979.43 g/m2. The maximum value reached 11 799.00 g/m2 in summer. The multivariable statistical analysis showed that the biodiversity of the fouling community on seasonal test panels was the highest in summer and the lowest in winter. With extending the panel deployment period,the biodiversity indexes increased and community structure tends to be more stable also.
The investigation of marine fouling assemblages on a series of artificial test panels in Dongshan Bay was conducted from September 2008 to August 2009. A total of 102 species were identified and dominated by Ulva fasciata,Pennaria disticha,Haliplanella luciae,Saccostrea cucullata,Brachidontes variabilis,Amphibalanus reticulates,Podocerus brasiliensis,Elasmopus pecteniclus,Stenothoe valida,Caprella equilibra and Sinoflustra amoyensis etc. The fouling organisms were mainly composed of coastal and warm water affinities and the settlements occurred throughout the year,particularly from April to October. The average biomass on the monthly test panels was 979.43 g/m2. The maximum value reached 11 799.00 g/m2 in summer. The multivariable statistical analysis showed that the biodiversity of the fouling community on seasonal test panels was the highest in summer and the lowest in winter. With extending the panel deployment period,the biodiversity indexes increased and community structure tends to be more stable also.
2012, 34(6): 170-176.
Abstract:
The fluorescence labeled bacterium EGFP-Vibrio fluvialis were introduced into the digestive tract of Einephelus awoara by intragastic injection in order to trace this bacterium colonization and its effect on digestive enzyme in fish intestine. The results showed that labeled bacterium could be detected in forgut and midgut 12 h after intragastic injection,and the number of the labeled bacteria in forgut reached a peak value 7.1×105cfu/g 24 h after intragastic injection,in midgut the peak value 5.39×105 cfu/g was observed 36 h after intragastic injection,in hindgut the labeled bacterium was not detected until 24 h after intragastic injection and the peak value was only 2.44×104 cfu/g. This result indicated V. fluvialis tended to adhere in forgut and midgut. Bacterium was still detected in forgut and midgut 96 h after intragastic injection,but not detected in hindgut. This indicated that forgut and midgut were the main location for bacteria colonization. The results also showed that the activity of alkaline protease and amylase in forgut and midgut and lipase in hindgut were significantly decreased after V. fluvialis colonization. This result implied that V. fluvialis could affect activity of digestive enzyme in the fish gut after colonization,which might be one of the pathogenesis of V. fluvialis.
The fluorescence labeled bacterium EGFP-Vibrio fluvialis were introduced into the digestive tract of Einephelus awoara by intragastic injection in order to trace this bacterium colonization and its effect on digestive enzyme in fish intestine. The results showed that labeled bacterium could be detected in forgut and midgut 12 h after intragastic injection,and the number of the labeled bacteria in forgut reached a peak value 7.1×105cfu/g 24 h after intragastic injection,in midgut the peak value 5.39×105 cfu/g was observed 36 h after intragastic injection,in hindgut the labeled bacterium was not detected until 24 h after intragastic injection and the peak value was only 2.44×104 cfu/g. This result indicated V. fluvialis tended to adhere in forgut and midgut. Bacterium was still detected in forgut and midgut 96 h after intragastic injection,but not detected in hindgut. This indicated that forgut and midgut were the main location for bacteria colonization. The results also showed that the activity of alkaline protease and amylase in forgut and midgut and lipase in hindgut were significantly decreased after V. fluvialis colonization. This result implied that V. fluvialis could affect activity of digestive enzyme in the fish gut after colonization,which might be one of the pathogenesis of V. fluvialis.
2012, 34(6): 177-186.
Abstract:
Axenation of four strains of marine microalgae(Isochrysis galbana, Chlorella sp. CV, Chlorella sp. C95 and Chlorella sp. C146) was carried out by using several common antibiotics(including ampicillin, streptomycin, chloramphenicol and kanamycin). The growth characteristics and biochemical compositions of four strains between axenic and nonaxenic cultures were investigated. The results showed: the growth of microalgae would be inhibited if the concentrations of single antibiotic or combined antibiotics were equal or higher than 100 mg/L, while the growth would be stimulated if the concentrations of some single or combined antibiotics were at 50mg/L; the axenic culture of I. galbana was obtained by combinedly using 200 mg/L of ampicillin, streptomycin and kanamycin, and the axenic cultures of C. CV, C. 95 and C. C146 were obtained by singly using 100, 50 and 50 mg/L of chloramphenicol respectively; the duration of stationary phase of the four axenic cultures prolonged for about 15 days, and the axenic algae could maintain a good suspension property rather than began aging prematurely; the contents of chlorophyll A, lutein and total lipids in axenic I. galbana and total protein in axenic C. CV and C. 95 increased significantly, and the composition of fatty acids such as EPA and PUFA in axenic Chlorella species changed markedly.
Axenation of four strains of marine microalgae(Isochrysis galbana, Chlorella sp. CV, Chlorella sp. C95 and Chlorella sp. C146) was carried out by using several common antibiotics(including ampicillin, streptomycin, chloramphenicol and kanamycin). The growth characteristics and biochemical compositions of four strains between axenic and nonaxenic cultures were investigated. The results showed: the growth of microalgae would be inhibited if the concentrations of single antibiotic or combined antibiotics were equal or higher than 100 mg/L, while the growth would be stimulated if the concentrations of some single or combined antibiotics were at 50mg/L; the axenic culture of I. galbana was obtained by combinedly using 200 mg/L of ampicillin, streptomycin and kanamycin, and the axenic cultures of C. CV, C. 95 and C. C146 were obtained by singly using 100, 50 and 50 mg/L of chloramphenicol respectively; the duration of stationary phase of the four axenic cultures prolonged for about 15 days, and the axenic algae could maintain a good suspension property rather than began aging prematurely; the contents of chlorophyll A, lutein and total lipids in axenic I. galbana and total protein in axenic C. CV and C. 95 increased significantly, and the composition of fatty acids such as EPA and PUFA in axenic Chlorella species changed markedly.
2012, 34(6): 187-194.
Abstract:
Green tides is a new kind of marine ecological disaster in the HuanghaiSea recurrent every year from May to July since 2007 which caused great environmental impacts and economy loss. To determine the origin and early development process of this phenomenon, our group carried out multi-cruise observations in Jiangsu coastal areas from April to June during 2009-2010 and studied the main causes and variations of floating algal transport pathways. The results showed that the floating green algae patches were all first observed around the Sun Island around Xiaoyangkou in the south part of Jiangsu coast during 2009-2010, and drifting northward later on with the expansion of covering and influenced area. The developmental processes were similar in the 2 studied years which can be divided into the patches floating, aggregation and massive green tide forming stage. The blooming time, covering area and transportation pathways of the green tides varied between 2009 and 2010. The seawater temperature may be an important role in the blooming of the green tides.
Green tides is a new kind of marine ecological disaster in the HuanghaiSea recurrent every year from May to July since 2007 which caused great environmental impacts and economy loss. To determine the origin and early development process of this phenomenon, our group carried out multi-cruise observations in Jiangsu coastal areas from April to June during 2009-2010 and studied the main causes and variations of floating algal transport pathways. The results showed that the floating green algae patches were all first observed around the Sun Island around Xiaoyangkou in the south part of Jiangsu coast during 2009-2010, and drifting northward later on with the expansion of covering and influenced area. The developmental processes were similar in the 2 studied years which can be divided into the patches floating, aggregation and massive green tide forming stage. The blooming time, covering area and transportation pathways of the green tides varied between 2009 and 2010. The seawater temperature may be an important role in the blooming of the green tides.
2012, 34(6): 195-204.
Abstract:
The main stony coral diseases in Xisha Archipelago were surveyed from May to October,2010 and from April to August,2011. Nine diseases,including coral bleaching,white spot disease,coral black disease,yellow inflammatory like syndrome and pink syndrome,were found in 14 species of stony coral,such as Porites pukoensis,Porites andrewsi,Montipora spp.,Pocillopora spp.,Acropora spp.,Goniastrea spp.,Porites lutea,Porites spp.. The yellow inflammatory-like disease of Porites pukoensis and bleaching in Porites andrewsi were very predominant in this area. The yellow inflammatory-like disease of Porites pukoensis was mainly distributed in the sea near Yongxing Island. Some yellow pus-like secreta presented in its lesion. The lesion was from 0.02 to 12.00 cm2 and the polyps in the lesion were normally growing,curling or missing. This disease might be caused by mechanical damage or other unknown reasons. The recure of the disease caused by mechanical damage would be happened in two to three months. Although it would be disappeared in 10 to 20 days while the wound was small,the yellow secreta would be disappeared or not after one to three months while the disease caused by other reasons. Bleaching of Porties andrewsi appeared in the sea near Qilian Island. The symptoms of this disease include complete bleaching,part bleaching or white spot disease. The polyps in its lesion missed and the skeleton was very white. It is the first report on coral diseases in Xisha Archipelago of South China Sea and will provide information and data for further study of coral disease in Xisha in future.
The main stony coral diseases in Xisha Archipelago were surveyed from May to October,2010 and from April to August,2011. Nine diseases,including coral bleaching,white spot disease,coral black disease,yellow inflammatory like syndrome and pink syndrome,were found in 14 species of stony coral,such as Porites pukoensis,Porites andrewsi,Montipora spp.,Pocillopora spp.,Acropora spp.,Goniastrea spp.,Porites lutea,Porites spp.. The yellow inflammatory-like disease of Porites pukoensis and bleaching in Porites andrewsi were very predominant in this area. The yellow inflammatory-like disease of Porites pukoensis was mainly distributed in the sea near Yongxing Island. Some yellow pus-like secreta presented in its lesion. The lesion was from 0.02 to 12.00 cm2 and the polyps in the lesion were normally growing,curling or missing. This disease might be caused by mechanical damage or other unknown reasons. The recure of the disease caused by mechanical damage would be happened in two to three months. Although it would be disappeared in 10 to 20 days while the wound was small,the yellow secreta would be disappeared or not after one to three months while the disease caused by other reasons. Bleaching of Porties andrewsi appeared in the sea near Qilian Island. The symptoms of this disease include complete bleaching,part bleaching or white spot disease. The polyps in its lesion missed and the skeleton was very white. It is the first report on coral diseases in Xisha Archipelago of South China Sea and will provide information and data for further study of coral disease in Xisha in future.
2012, 34(6): 205-209.
Abstract:
The defense responses of Porphyra haitanensis to oligoagars with different degree of polymerizations (DP) were investigated. Oligoagars with three different DPs (agartirose, hexaose and dodecaose) were used to evaluate the effect of structure of oligosaccharides on inducing the defense response in P. haitanensis. After elicited with 100 μg/ml oligoagars, the growing status of P. haitanensis gametophyte was observed by microscope and ultrastructure examination. The impact of the algal response to oligoagars on the epiphytic bacteria was determined by examing the numbers of associated bacteria. The expression level of NADPH oxidase (named Phrboh) was detected by real-time PCR. The concentration of H2O2 in the medium was determined by measuring the dimerization of (p-hydroxyphenyl) acetic acid. Results indicated that P. haitanensis responded with an oxidative burst and rapid increases in Phrboh expression when agarotriose and agarohexaose were added to the growth medium. Further, elicitation of P. haitanensis with these two oligoagars caused elimination of epiphytic bacteria. The rot of thallus was lightened and cells of P. haitanensis kept well status in the four days culture. In them, agarohexaose showed stronger effects. Agarhexaose elicited a release of hydrogen peroxide in less than 15 min. The expression of Pyrboh was up-regulated in five minutes and 16.5 fold increases in the expression were observed 5 min after addition of agarohexaose. In contrast, agarododecaose did not have any effect. In summary, P. haitanensis respond immediately after exposure to agarotriose and agarohexaose with a variety of physiological changes, especially agarhexaose could elicit strongest response to P. haitanensis. Oligoagars with high degree of polymerization showed no effect.
The defense responses of Porphyra haitanensis to oligoagars with different degree of polymerizations (DP) were investigated. Oligoagars with three different DPs (agartirose, hexaose and dodecaose) were used to evaluate the effect of structure of oligosaccharides on inducing the defense response in P. haitanensis. After elicited with 100 μg/ml oligoagars, the growing status of P. haitanensis gametophyte was observed by microscope and ultrastructure examination. The impact of the algal response to oligoagars on the epiphytic bacteria was determined by examing the numbers of associated bacteria. The expression level of NADPH oxidase (named Phrboh) was detected by real-time PCR. The concentration of H2O2 in the medium was determined by measuring the dimerization of (p-hydroxyphenyl) acetic acid. Results indicated that P. haitanensis responded with an oxidative burst and rapid increases in Phrboh expression when agarotriose and agarohexaose were added to the growth medium. Further, elicitation of P. haitanensis with these two oligoagars caused elimination of epiphytic bacteria. The rot of thallus was lightened and cells of P. haitanensis kept well status in the four days culture. In them, agarohexaose showed stronger effects. Agarhexaose elicited a release of hydrogen peroxide in less than 15 min. The expression of Pyrboh was up-regulated in five minutes and 16.5 fold increases in the expression were observed 5 min after addition of agarohexaose. In contrast, agarododecaose did not have any effect. In summary, P. haitanensis respond immediately after exposure to agarotriose and agarohexaose with a variety of physiological changes, especially agarhexaose could elicit strongest response to P. haitanensis. Oligoagars with high degree of polymerization showed no effect.
2012, 34(6): 210-216.
Abstract:
On the basis of linear potential theory,an analytical study on the hydrodynamic performance of a submerged breakwater is given in front of a partially reflecting sidewall.The calculating method of the transmission and reflection coefficients of the submerged breakwater is developed by using the matched eigenfunction expansion method.The calculated results of the transmission and reflection coefficients agree very well with those by the boundary element method.The main effect factors of the transmission and reflection coefficients of the breakwater are analyzed.The transmission coefficient of the submerged breakwater increases with the increasing reflection coefficient of the partially reflecting sidewall.With the increasing value of the relative breakwater width or the relative space between the breakwater and the sidewall,both the transmission coefficient and the reflection coefficient of the breakwater vary periodically.But the variations of the reflection and transmission coefficients are just the opposite.
On the basis of linear potential theory,an analytical study on the hydrodynamic performance of a submerged breakwater is given in front of a partially reflecting sidewall.The calculating method of the transmission and reflection coefficients of the submerged breakwater is developed by using the matched eigenfunction expansion method.The calculated results of the transmission and reflection coefficients agree very well with those by the boundary element method.The main effect factors of the transmission and reflection coefficients of the breakwater are analyzed.The transmission coefficient of the submerged breakwater increases with the increasing reflection coefficient of the partially reflecting sidewall.With the increasing value of the relative breakwater width or the relative space between the breakwater and the sidewall,both the transmission coefficient and the reflection coefficient of the breakwater vary periodically.But the variations of the reflection and transmission coefficients are just the opposite.
2012, 34(6): 217-227.
Abstract:
2012, 34(6): 228-237.
Abstract:
Email alert
RSS