2011 Vol. 33, No. 4
Display Method:
2011, 33(4): 1-8.
Abstract:
Anaerobic ammonium oxidation (anammox) is the process of microbiological conversion of ammonium to dinitrogen gas and is mainly employed in waste water engineers. In recent years, it was found that anammox was widely distributed in the marine environments and played an important role in marine nitrogen cycle, and influenced the carbon cycle and global climate change. It has been recognized as a major pathway for the removal of fixed N from the marine ecosystem. Ladderane lipids are unique chemical biomarkers of anaerobic ammonium-oxidizing bacteria, and have potential implication for chemotaxonomy and paleooceangraphy. Anaerobic ammonium-oxidizing bacteria and anaerobic ammonium oxidation have become hot-spot research fields in the marine biogeochemistry, microbiology and organic geochemistry.
Anaerobic ammonium oxidation (anammox) is the process of microbiological conversion of ammonium to dinitrogen gas and is mainly employed in waste water engineers. In recent years, it was found that anammox was widely distributed in the marine environments and played an important role in marine nitrogen cycle, and influenced the carbon cycle and global climate change. It has been recognized as a major pathway for the removal of fixed N from the marine ecosystem. Ladderane lipids are unique chemical biomarkers of anaerobic ammonium-oxidizing bacteria, and have potential implication for chemotaxonomy and paleooceangraphy. Anaerobic ammonium-oxidizing bacteria and anaerobic ammonium oxidation have become hot-spot research fields in the marine biogeochemistry, microbiology and organic geochemistry.
2011, 33(4): 9-18.
Abstract:
Both Newton cooling scheme (i.e. prescribed total heat fluxes added with a relaxation term) and bulk formula parameterization scheme are widely used in offline Ocean General Circulation model simulations. These two thermal forcing schemes are compared here in two simulations using LASG/IAP climate ocean model (named LICOM) in terms of the performance over tropical Pacific Ocean. The results indicate that for both the annual mean SST distribution and the annual cycle of SST over tropical pacific, the two schemes show reasonable performance, although the Newton cooling scheme shows even less bias due to its relaxation to observed climatological SST. The El Nio amplitude in the Newton cooling scheme simulation is weaker than that in observation, due to the overestimated negative heat flux feedback which is related with the thermal coupling coefficient. And the suppressed El Nio could further lead to a narrower meridional scale of the SST anomalies in the eastern Pacific. With a reasonable negative heat flux feedback in bulk formula simulation, the model exhibits a more reliable El Nio amplitude and spatial distribution. The study demonstrates that if the simulation aims to get a realistic mean state, the Newton cooling is recommended, but if the simulation focuses on interannual variability of the tropical ocean, the bulk parameterization scheme should be used.
Both Newton cooling scheme (i.e. prescribed total heat fluxes added with a relaxation term) and bulk formula parameterization scheme are widely used in offline Ocean General Circulation model simulations. These two thermal forcing schemes are compared here in two simulations using LASG/IAP climate ocean model (named LICOM) in terms of the performance over tropical Pacific Ocean. The results indicate that for both the annual mean SST distribution and the annual cycle of SST over tropical pacific, the two schemes show reasonable performance, although the Newton cooling scheme shows even less bias due to its relaxation to observed climatological SST. The El Nio amplitude in the Newton cooling scheme simulation is weaker than that in observation, due to the overestimated negative heat flux feedback which is related with the thermal coupling coefficient. And the suppressed El Nio could further lead to a narrower meridional scale of the SST anomalies in the eastern Pacific. With a reasonable negative heat flux feedback in bulk formula simulation, the model exhibits a more reliable El Nio amplitude and spatial distribution. The study demonstrates that if the simulation aims to get a realistic mean state, the Newton cooling is recommended, but if the simulation focuses on interannual variability of the tropical ocean, the bulk parameterization scheme should be used.
2011, 33(4): 19-28.
Abstract:
Using the advanced climate ocean-atmosphere coupled model described in the first paper of this series of studies, response analyses of inter-decadal variations of the Atlantic thermohaline circulation by ocean-atmosphere elements were deliberated. For studying the relationship between the ocean elements of the North Atlantic and inter-decadal variations of Atlantic thermohaline circulation, subpolar sea-surface-density index (SSI) and North-Atlantic-Current Strength Index (NSI) were defined and analyzed. The results of analyses indicate that SSI changes 7 years earlier than Atlantic meridional overturning circulation (MOC) while NSI changing 4 years earlier than MOC. The strength of water overflows from Greenland-Scotland sea ridge (including Denmark Strait and Faro Strait),which is an important water resource of North Atlantic deep water, changes 3 years ahead MOC.The inter-decadal variations of Atlantic thermohaline circulation THC are influenced by North Atlantic atmosphere elements significantly.2 years before subpolar current and North Atlantic Current (NAC) reaching their full strength, High-latitude atmosphere is abnormal in the pattern of cyclonic circulation and middle-latitude atmosphere is abnormal in the pattern of anticyclonic circulation. Meanwhile, the sea surface heat flux in Atlantic subpolar sea area is negative anomaly. All of those abnormal conditions enhance the strength of subpolar current and NAC.More water with higher salinity intruding into Greenland-Icelandic-Norwegian Sea (GIN) brings higher sea surface density of GIN. This weakens the stability of water stratification and increases the probability of occurrence of deep convection.Meanwhile, the variation of atmosphere influences the deep water generating process in GIN by the curl of wind stress and sea surface heat flux. Then the strength of water overflows from Greenland-Scotland sea ridge is strengthened.
Using the advanced climate ocean-atmosphere coupled model described in the first paper of this series of studies, response analyses of inter-decadal variations of the Atlantic thermohaline circulation by ocean-atmosphere elements were deliberated. For studying the relationship between the ocean elements of the North Atlantic and inter-decadal variations of Atlantic thermohaline circulation, subpolar sea-surface-density index (SSI) and North-Atlantic-Current Strength Index (NSI) were defined and analyzed. The results of analyses indicate that SSI changes 7 years earlier than Atlantic meridional overturning circulation (MOC) while NSI changing 4 years earlier than MOC. The strength of water overflows from Greenland-Scotland sea ridge (including Denmark Strait and Faro Strait),which is an important water resource of North Atlantic deep water, changes 3 years ahead MOC.The inter-decadal variations of Atlantic thermohaline circulation THC are influenced by North Atlantic atmosphere elements significantly.2 years before subpolar current and North Atlantic Current (NAC) reaching their full strength, High-latitude atmosphere is abnormal in the pattern of cyclonic circulation and middle-latitude atmosphere is abnormal in the pattern of anticyclonic circulation. Meanwhile, the sea surface heat flux in Atlantic subpolar sea area is negative anomaly. All of those abnormal conditions enhance the strength of subpolar current and NAC.More water with higher salinity intruding into Greenland-Icelandic-Norwegian Sea (GIN) brings higher sea surface density of GIN. This weakens the stability of water stratification and increases the probability of occurrence of deep convection.Meanwhile, the variation of atmosphere influences the deep water generating process in GIN by the curl of wind stress and sea surface heat flux. Then the strength of water overflows from Greenland-Scotland sea ridge is strengthened.
2011, 33(4): 29-37.
Abstract:
With the help of the controlled auto-regression and moving-average model(CARMA) based on system and cybernetics approaches, this paper studies the system response of the tidal propagation in the Zhujiang(Pearl)River Estuary(PRE). By system model identification, the CARMA models'parameters of the single-input single-output(SISO) for 59 stations in January 2001 of dry season and the double-input single-output(DISO) for 65 stations in July 1999 of flood season, were established with the tidal elevation and river inflow in the PRE. Frequency response analysis based on the system models provides some important insights into the PRE dynamic system. It is found that the nature frequency of PRE both in dry season and flood season are almost at the shallow water tidal bands with period 6~10 h.The experiments proved the nature frequency of resonance found in PRE were dependable, and also clarified that the response approach based on system and cybernetics can help us find the periods of resonance of the estuarine dynamical system.
With the help of the controlled auto-regression and moving-average model(CARMA) based on system and cybernetics approaches, this paper studies the system response of the tidal propagation in the Zhujiang(Pearl)River Estuary(PRE). By system model identification, the CARMA models'parameters of the single-input single-output(SISO) for 59 stations in January 2001 of dry season and the double-input single-output(DISO) for 65 stations in July 1999 of flood season, were established with the tidal elevation and river inflow in the PRE. Frequency response analysis based on the system models provides some important insights into the PRE dynamic system. It is found that the nature frequency of PRE both in dry season and flood season are almost at the shallow water tidal bands with period 6~10 h.The experiments proved the nature frequency of resonance found in PRE were dependable, and also clarified that the response approach based on system and cybernetics can help us find the periods of resonance of the estuarine dynamical system.
2011, 33(4): 38-48.
Abstract:
The performance of the fast version of IAP/LASG coupled climate system model, named FGOALS_gl, in simulating the East Asian subtropical westerly jet (thereafter EASWJ) is evaluated. The model can reasonably reproduce the climatological characteristics of the EASWJ, including the spatial structure and the seasonal meridional displacement. Compared with the NCEP/NCAR reanalysis data, the major model deficiency is the weaker intensity and the southward shift of the EASWJ. It is found that the deficiency of EASWJ simulation is resulted from the bias in middle-upper troposphere temperature. The cold tropospheric temperature bias south to the EASWJ axis is stronger than that in the north. On the interannual timescale, the meridional displacement of EASWJ is reasonably simulated, although the model overestimates the interannual variability which is partly attributed to the bias in ENSO simulation. The southward displacement of EASWJ is evident in the summer of El Nio decaying year. The NCEP/NCAR reanalysis data and FGAOLS_gl are consistent in this regard. Since the simulated ENSO is stronger and persists into the following autumn, thus has a phase-locking in spring-summer. Correspondingly the ENSO-related tropospheric warming is still significant in El Nio decaying summer, leading to a stronger interannual variability of the EASWJ.
The performance of the fast version of IAP/LASG coupled climate system model, named FGOALS_gl, in simulating the East Asian subtropical westerly jet (thereafter EASWJ) is evaluated. The model can reasonably reproduce the climatological characteristics of the EASWJ, including the spatial structure and the seasonal meridional displacement. Compared with the NCEP/NCAR reanalysis data, the major model deficiency is the weaker intensity and the southward shift of the EASWJ. It is found that the deficiency of EASWJ simulation is resulted from the bias in middle-upper troposphere temperature. The cold tropospheric temperature bias south to the EASWJ axis is stronger than that in the north. On the interannual timescale, the meridional displacement of EASWJ is reasonably simulated, although the model overestimates the interannual variability which is partly attributed to the bias in ENSO simulation. The southward displacement of EASWJ is evident in the summer of El Nio decaying year. The NCEP/NCAR reanalysis data and FGAOLS_gl are consistent in this regard. Since the simulated ENSO is stronger and persists into the following autumn, thus has a phase-locking in spring-summer. Correspondingly the ENSO-related tropospheric warming is still significant in El Nio decaying summer, leading to a stronger interannual variability of the EASWJ.
2011, 33(4): 49-61.
Abstract:
Based on the monthly heat content and sea temperature datasets over the South China Sea (SCS) from January 1980 to December 2007, the temporal and spatial distribution characteristics of the heat content over SCS and its relationship with the onset of the summer monsoon(SCSM) was analyzed, after that, the possible contributions to the anomalous onset times of SCSM was further explored as well. It is showed that the main area of the upper layer heat content changes is located over the south central SCS (8°~16°N,110°~120°E), and the strongest signal of the heat content changes is kept in the subsurface (100~200 m) over the SCS. Compared with the early onset monsoon years, the features of the winter-spring heat content over the SCS holds the opposite polarity during the late onset years. The early (late) onset of the SCSM is accompanied by the positive (negative) heat content anomalies during the previous winter-spring except for December. Furthermore, it is also pointed out that the negative correlation coefficient peaks when the heat content anomalies lead the onset of the SCSM by 1~5 months, especially when the heat content anomaly is fixed in the previous March. Thus, the heat content in March over the south central SCS is a good premonitory signal for the onset of the SCSM. The positive (negative) heat content anomalies over the SCS as well as the positive (negative) upper ocean heat anomalies, which increase (decrease) the temperature gradient between ocean and land before the onset of the SCSM, are conducive to the early (late) onset of the SCSM eventually.
Based on the monthly heat content and sea temperature datasets over the South China Sea (SCS) from January 1980 to December 2007, the temporal and spatial distribution characteristics of the heat content over SCS and its relationship with the onset of the summer monsoon(SCSM) was analyzed, after that, the possible contributions to the anomalous onset times of SCSM was further explored as well. It is showed that the main area of the upper layer heat content changes is located over the south central SCS (8°~16°N,110°~120°E), and the strongest signal of the heat content changes is kept in the subsurface (100~200 m) over the SCS. Compared with the early onset monsoon years, the features of the winter-spring heat content over the SCS holds the opposite polarity during the late onset years. The early (late) onset of the SCSM is accompanied by the positive (negative) heat content anomalies during the previous winter-spring except for December. Furthermore, it is also pointed out that the negative correlation coefficient peaks when the heat content anomalies lead the onset of the SCSM by 1~5 months, especially when the heat content anomaly is fixed in the previous March. Thus, the heat content in March over the south central SCS is a good premonitory signal for the onset of the SCSM. The positive (negative) heat content anomalies over the SCS as well as the positive (negative) upper ocean heat anomalies, which increase (decrease) the temperature gradient between ocean and land before the onset of the SCSM, are conducive to the early (late) onset of the SCSM eventually.
2011, 33(4): 62-73.
Abstract:
Intensity index series of different propagation mode are abstracted from the wavenumber-frequency analysis result of every year, the interannual oscillation spectrum characteristics of atmospheric boreal summer intraseasonal oscillations are analyzed and the effects of air-sea interaction on the interannual oscillations of atmospheric boreal summer intraseasonal oscillations over the tropical ocean are investigated using observational OLR and outcome of air-sea coupling numerical simulation experiments.It is shown that the distinct oscillation period of poleward westward propagation and northward propagation in the Indian Ocean is quasi-biannual while both of quasi-biannual and quasi 5-year are contained by eastward propagation of equator, northward propagation in South China Sea and northward propagation in western Pacific.The northward propagation in South China Sea is the only mode which holds the main oscillation period of quasi 5-year.There are reinforcing and weakening effects of air-sea interactions on the intensity of quasi-biannual and quasi 5-year oscillations of different index.By comparing different oceans, the most strengthen effect on quasi-biannual and quasi 5-year oscillations of eastward propagation, or quasi-biannual and quasi 5-year oscillations of northward propagation in South China Sea, is the air-sea interaction over western Pacific; the most strengthen effect on quasi-biannual oscillation of westward propagation, or quasi-biannual and quasi 5-year oscillations of northward propagation in western Pacific, is the air-sea interaction over the Indian Ocean.
Intensity index series of different propagation mode are abstracted from the wavenumber-frequency analysis result of every year, the interannual oscillation spectrum characteristics of atmospheric boreal summer intraseasonal oscillations are analyzed and the effects of air-sea interaction on the interannual oscillations of atmospheric boreal summer intraseasonal oscillations over the tropical ocean are investigated using observational OLR and outcome of air-sea coupling numerical simulation experiments.It is shown that the distinct oscillation period of poleward westward propagation and northward propagation in the Indian Ocean is quasi-biannual while both of quasi-biannual and quasi 5-year are contained by eastward propagation of equator, northward propagation in South China Sea and northward propagation in western Pacific.The northward propagation in South China Sea is the only mode which holds the main oscillation period of quasi 5-year.There are reinforcing and weakening effects of air-sea interactions on the intensity of quasi-biannual and quasi 5-year oscillations of different index.By comparing different oceans, the most strengthen effect on quasi-biannual and quasi 5-year oscillations of eastward propagation, or quasi-biannual and quasi 5-year oscillations of northward propagation in South China Sea, is the air-sea interaction over western Pacific; the most strengthen effect on quasi-biannual oscillation of westward propagation, or quasi-biannual and quasi 5-year oscillations of northward propagation in western Pacific, is the air-sea interaction over the Indian Ocean.
2011, 33(4): 74-78.
Abstract:
The frequency spectrum of wind-generated microscale waves is brought forward using the color image collected by a sea surface microstructure optical measuring device. And on this basis, the relationship between the wave number spectrum and frequency spectrum of the microscale waves can be established utilizing dispersion relations of capillary gravity waves. Furthermore, the response of the frequency spectrum of the microscale waves to the change of frequency is studied. It can be found that the frequency spectrum of the microscale waves is proportional to the power of α of frequency and that the value of α which is unique at the same speed increases with speed.
The frequency spectrum of wind-generated microscale waves is brought forward using the color image collected by a sea surface microstructure optical measuring device. And on this basis, the relationship between the wave number spectrum and frequency spectrum of the microscale waves can be established utilizing dispersion relations of capillary gravity waves. Furthermore, the response of the frequency spectrum of the microscale waves to the change of frequency is studied. It can be found that the frequency spectrum of the microscale waves is proportional to the power of α of frequency and that the value of α which is unique at the same speed increases with speed.
2011, 33(4): 79-87.
Abstract:
Sea ice has negative influences on the oil/gas platform structure, the nautical transportation and the construction operation during the ice-covered season in the Bohai Sea. The accurate, continuous and real-time field observation of sea ice parameters is very important for the reliability analysis of oil exploration,the validation of sea ice numerical model and the revision of satellite remote sensing data. A digital image processing technology was adopted to obtain the sea ice parameters according to the dynamic distribution characteristics of sea ice in the oil exploration areas of the Bohai Sea. A precise algorithm and an effective software system were developed to determine the ice thickness, the ice velocity and the ice concentration, respectively. In the winter of 2009—2010, this sea ice digital processing program was utilized to observe the ice parameters in the JZ20-2 oil field of Bohai Sea. The ice parameters of thickness, concentration and velocity were obtained of the whole winter. With the field observations, it can be found that the sea ice digital processing program developed has the advantages of convenient operation and high accuracy reliability. With further improvements, it can be an important portion of the field observation of sea ice in the Bohai Sea.
Sea ice has negative influences on the oil/gas platform structure, the nautical transportation and the construction operation during the ice-covered season in the Bohai Sea. The accurate, continuous and real-time field observation of sea ice parameters is very important for the reliability analysis of oil exploration,the validation of sea ice numerical model and the revision of satellite remote sensing data. A digital image processing technology was adopted to obtain the sea ice parameters according to the dynamic distribution characteristics of sea ice in the oil exploration areas of the Bohai Sea. A precise algorithm and an effective software system were developed to determine the ice thickness, the ice velocity and the ice concentration, respectively. In the winter of 2009—2010, this sea ice digital processing program was utilized to observe the ice parameters in the JZ20-2 oil field of Bohai Sea. The ice parameters of thickness, concentration and velocity were obtained of the whole winter. With the field observations, it can be found that the sea ice digital processing program developed has the advantages of convenient operation and high accuracy reliability. With further improvements, it can be an important portion of the field observation of sea ice in the Bohai Sea.
2011, 33(4): 88-94.
Abstract:
In order to find a simple and continuous method to measure a suspended sediment content in a high turbidity region, a conductivity sensor was used to examine the conductivity in different sediment content seawater. Sediments from the Huanghe River Delta were used. The previous test has proven that good linear relationships exist between the suspended sediment content and the conductivity. On that basis, the scope of study was expanded. And the influencing factors of such relationships were also investigated. The results show that salinity, temperature and particle size have some influence on the conductivity, among which salinity is the most influencing factor and the influence of particle size is not important. In this way, the general relationship between the suspended sediment content and electrical conductivity was achieved through a large number of test data in a large scale of salinity and temperature. They provide reliable data support for realizing the monitoring system in situ.
In order to find a simple and continuous method to measure a suspended sediment content in a high turbidity region, a conductivity sensor was used to examine the conductivity in different sediment content seawater. Sediments from the Huanghe River Delta were used. The previous test has proven that good linear relationships exist between the suspended sediment content and the conductivity. On that basis, the scope of study was expanded. And the influencing factors of such relationships were also investigated. The results show that salinity, temperature and particle size have some influence on the conductivity, among which salinity is the most influencing factor and the influence of particle size is not important. In this way, the general relationship between the suspended sediment content and electrical conductivity was achieved through a large number of test data in a large scale of salinity and temperature. They provide reliable data support for realizing the monitoring system in situ.
2011, 33(4): 95-103.
Abstract:
Based on the technology of remote sensing and geographic information system, land use data-base of a study area in the year of 1985 and 2005 was acquired. By the analysis of land use changes, the result shows that (1) from 1985 to 2005, among eight land use types, the area of agricultural land changes most, it decreases 2 048 km2, at a percentage of 31.4%; (2) By the main driving force of sea reclamation, the area of mainland coastline displacement is 370 km2, and East Guangdong,West Guangdong and the Zhujiang(Pearl) River Estuary occupy 12.6%, 31.2% and 56.2% respectively; (3) the area of construction land in the coastal regions of Zhuhai, Guangzhou, Shenzhen, the Daya Bay ,Shanwei and Shantou expands more than 10 times; (4) great changes have taken placed of land use in the area of Guangdong coastal zone and islands, and the land use type change direction and dynamic change degree of land use have significant spatial heterogeneity, the total integrated change degree of the study area is 24.2%, and in East Guangdong,West Guangdong and Zhujiang(Pearl) River Estuary regions are 15.6%, 22.8% and 28.2% respectively. A scientific basis can be provided for the sustainable use and management of ocastal land and marine resources.
Based on the technology of remote sensing and geographic information system, land use data-base of a study area in the year of 1985 and 2005 was acquired. By the analysis of land use changes, the result shows that (1) from 1985 to 2005, among eight land use types, the area of agricultural land changes most, it decreases 2 048 km2, at a percentage of 31.4%; (2) By the main driving force of sea reclamation, the area of mainland coastline displacement is 370 km2, and East Guangdong,West Guangdong and the Zhujiang(Pearl) River Estuary occupy 12.6%, 31.2% and 56.2% respectively; (3) the area of construction land in the coastal regions of Zhuhai, Guangzhou, Shenzhen, the Daya Bay ,Shanwei and Shantou expands more than 10 times; (4) great changes have taken placed of land use in the area of Guangdong coastal zone and islands, and the land use type change direction and dynamic change degree of land use have significant spatial heterogeneity, the total integrated change degree of the study area is 24.2%, and in East Guangdong,West Guangdong and Zhujiang(Pearl) River Estuary regions are 15.6%, 22.8% and 28.2% respectively. A scientific basis can be provided for the sustainable use and management of ocastal land and marine resources.
2011, 33(4): 104-110.
Abstract:
A transmittance-reflectance(T-R)method is one of the most important methods to measure the absorption coefficient of suspended particulate matter. The GF/F filter paper's hydration degree and the path-length amplification correction factor model play the key roles in the T-R method. The effect of the hydration degree of the GF/F filter paper on the optical properties was experimentally analyzed. The results show that the error of transmittance ratio, reflectances ratio and reflectance of the filter paper which is soaked 60~80 min, is the minimum, and their values are 3.0%, 0.5% and 0.5%. On this basis chlorella were used as a research object, the path-length amplification correction factor model of the T-R method was studied. The results show that a polynomial regression model is superior to a linear regression model and a power regression model; and a quadratic polynomial model is selected as the path-length amplification correction factor model of the T-R method. The regression interval is , and the average relative error is 9.19%.
A transmittance-reflectance(T-R)method is one of the most important methods to measure the absorption coefficient of suspended particulate matter. The GF/F filter paper's hydration degree and the path-length amplification correction factor model play the key roles in the T-R method. The effect of the hydration degree of the GF/F filter paper on the optical properties was experimentally analyzed. The results show that the error of transmittance ratio, reflectances ratio and reflectance of the filter paper which is soaked 60~80 min, is the minimum, and their values are 3.0%, 0.5% and 0.5%. On this basis chlorella were used as a research object, the path-length amplification correction factor model of the T-R method was studied. The results show that a polynomial regression model is superior to a linear regression model and a power regression model; and a quadratic polynomial model is selected as the path-length amplification correction factor model of the T-R method. The regression interval is , and the average relative error is 9.19%.
A numerical study of hydrothermal circulation patterns within the large hydrothermal sulfide deposit
2011, 33(4): 111-120.
Abstract:
To understand the distributions of the temperature and flow fields within the large hydrothermal sulfide deposit is important to study the formation and mineralization processes of seafloor hydrothermal deposits. Based on the results of ocean deep program (ODP), a hydrothermal deposit model with 3-layer is set up, and the distributions of the thermal and current fields under different permeability conditions are simulated using the Hydrothremal software, which is developed by U.S. Geological Survey (USGS). The results indicate that (1) in the homogenous model, the increase of Rayleigh number can cause the temperature decrease and the fluid flow faster; (2) heterogenic structures within the deposit have great influence on the distribution of the temperature fields; (3) the distributions of black smokers in mature deposit are related to many factors, such as heat source and permeability.
To understand the distributions of the temperature and flow fields within the large hydrothermal sulfide deposit is important to study the formation and mineralization processes of seafloor hydrothermal deposits. Based on the results of ocean deep program (ODP), a hydrothermal deposit model with 3-layer is set up, and the distributions of the thermal and current fields under different permeability conditions are simulated using the Hydrothremal software, which is developed by U.S. Geological Survey (USGS). The results indicate that (1) in the homogenous model, the increase of Rayleigh number can cause the temperature decrease and the fluid flow faster; (2) heterogenic structures within the deposit have great influence on the distribution of the temperature fields; (3) the distributions of black smokers in mature deposit are related to many factors, such as heat source and permeability.
2011, 33(4): 121-128.
Abstract:
The spatital distrubution of sulfate reduction and anaerobic oxidation of methane (AOM) was investigated in the Jiulong estuarine sediment based on the concentration profiles of geochemical parameters, including sulfate, methane, δc(34S-SO42-), δc(13C-CH4) and chlorine in pore water. Sulfate concentrations in pore water decrease remarkably with the depth. The sulfate is consumed completely at depth intervals 55 and 130 cm at two stations (J-A and J-E). There is no significant change for chloride concentration through the depth of the cores. The δ34S values of sulfate increase with the depth in both cores. It is suggested that sulfate reduction occurs within the upper 55 and 130 cm in the sediment at Stas J-A and J-E, respectively. Methane concentrations sharply increase at the depth of sulfate-methane transition (SMT), and the δc(13C-CH4) values become heavier due to the AOM. Overall, these data suggest methane is consumed mainly by anaerobic oxidation at the SMT. There is obvious positive correlation between the depth of the SMT and the salinity of overlying water at two stations. It is assumed that the depth of the SMT is mainly controlled by the gradient of sulfate which is controlled by the salinity of the overlying water in the Jiulong Estuary.
The spatital distrubution of sulfate reduction and anaerobic oxidation of methane (AOM) was investigated in the Jiulong estuarine sediment based on the concentration profiles of geochemical parameters, including sulfate, methane, δc(34S-SO42-), δc(13C-CH4) and chlorine in pore water. Sulfate concentrations in pore water decrease remarkably with the depth. The sulfate is consumed completely at depth intervals 55 and 130 cm at two stations (J-A and J-E). There is no significant change for chloride concentration through the depth of the cores. The δ34S values of sulfate increase with the depth in both cores. It is suggested that sulfate reduction occurs within the upper 55 and 130 cm in the sediment at Stas J-A and J-E, respectively. Methane concentrations sharply increase at the depth of sulfate-methane transition (SMT), and the δc(13C-CH4) values become heavier due to the AOM. Overall, these data suggest methane is consumed mainly by anaerobic oxidation at the SMT. There is obvious positive correlation between the depth of the SMT and the salinity of overlying water at two stations. It is assumed that the depth of the SMT is mainly controlled by the gradient of sulfate which is controlled by the salinity of the overlying water in the Jiulong Estuary.
2011, 33(4): 129-139.
Abstract:
The detailed biostratigraphic research has been applied to two ferromanganese crusts which are sampled on a mid-Pacific seamount using the method of biostratigraphy.The results reveal that the growth layers of these two samples are homologous and their calcareous nannofossil complexes are the same,too. Based on the identification of calcareous nannofossil imprints and original fossil remains,the main growth periods of the two samples are Late Paleocene,Mid-Late Eocene,Mid Miocene to Pliocene and Pliocene to Pleistocene. On the other hand,the two main growth gaps are at Oligocene and Early Eocene.
The detailed biostratigraphic research has been applied to two ferromanganese crusts which are sampled on a mid-Pacific seamount using the method of biostratigraphy.The results reveal that the growth layers of these two samples are homologous and their calcareous nannofossil complexes are the same,too. Based on the identification of calcareous nannofossil imprints and original fossil remains,the main growth periods of the two samples are Late Paleocene,Mid-Late Eocene,Mid Miocene to Pliocene and Pliocene to Pleistocene. On the other hand,the two main growth gaps are at Oligocene and Early Eocene.
2011, 33(4): 140-146.
Abstract:
Species, coverage and recruitment of hermatypic coral and mainly-related environmental factors were investigated at five stations(Yongxing Island, Shidao Island, Xishazhou, Zhaoshu Island and North Island) during 2005-2009.The results show that hermatypic coral has been degraded year by year in Xisha ecological monitoring area.The live hermatypic coral coverage decreases from 65% in 2005 to 7.93% in 2009. In contrast, the dead coral coverage increases from 4.70% in 2005 to 72.90% in 2009.A new coral recruitment also becomes less and less. In 2005 the new coral recruitment is 1.21 ind/m3 but only 0.07 ind/m3 in 2009.Further analysis indicates that the hermatypic coral declines for many reasons in Xisha ecological monitoring area, such as bioerosion, warm water, ocean acidification and overfishing,etc, while outbreaks of the coral-eating crown-of-thorns starfish(Acanthaster planci)are the main reason which causes the hermatypic coral to decline in Xisha ecological monitoring area.
Species, coverage and recruitment of hermatypic coral and mainly-related environmental factors were investigated at five stations(Yongxing Island, Shidao Island, Xishazhou, Zhaoshu Island and North Island) during 2005-2009.The results show that hermatypic coral has been degraded year by year in Xisha ecological monitoring area.The live hermatypic coral coverage decreases from 65% in 2005 to 7.93% in 2009. In contrast, the dead coral coverage increases from 4.70% in 2005 to 72.90% in 2009.A new coral recruitment also becomes less and less. In 2005 the new coral recruitment is 1.21 ind/m3 but only 0.07 ind/m3 in 2009.Further analysis indicates that the hermatypic coral declines for many reasons in Xisha ecological monitoring area, such as bioerosion, warm water, ocean acidification and overfishing,etc, while outbreaks of the coral-eating crown-of-thorns starfish(Acanthaster planci)are the main reason which causes the hermatypic coral to decline in Xisha ecological monitoring area.
2011, 33(4): 147-154.
Abstract:
The bacterial strain AC-11 was isolated from marine aquaculture pond of the Third Institute of Oceanography in Xiamen, China, and its 16SrDNA sequence demonstrated 99.78% similarity to Klebsiella pneumoniae subsp. pneumoniae. A total of 3 lytic phages KP1, KP2 and KP3 were isolated with this bacterial strain as the host using double-layer agar method. Phage KP2 was from the same aquaculture pond where the host strain was isolated, and the other two phages were from Yuan Dang Lake (marine water) in Xiamen, China. Morphology of both phages and host were observed under transmission electron microscope. The restriction patterns of nucleic acid of the phages were estimated by dsDNA restriction enzyme BglⅡand EcoRⅤ. All of the 3 phages belonged to family Siphoviridae, but with different genome fingerprint patterns. The physiological characteristics of the phages such as the optimal multiplicity of infection, the one-step growth curves and the sensitivity to temperature, pH, UV light, ether and chloroform were also tested. The results indicated that the phages had different biological characteristics and thus belonged to different strain types. This could contribute to the diversity of phages, the diagnosis and treatment of potential diseases caused by Klebsiella pneumoniae and typing of the relating Klebsiella bacteria.
The bacterial strain AC-11 was isolated from marine aquaculture pond of the Third Institute of Oceanography in Xiamen, China, and its 16SrDNA sequence demonstrated 99.78% similarity to Klebsiella pneumoniae subsp. pneumoniae. A total of 3 lytic phages KP1, KP2 and KP3 were isolated with this bacterial strain as the host using double-layer agar method. Phage KP2 was from the same aquaculture pond where the host strain was isolated, and the other two phages were from Yuan Dang Lake (marine water) in Xiamen, China. Morphology of both phages and host were observed under transmission electron microscope. The restriction patterns of nucleic acid of the phages were estimated by dsDNA restriction enzyme BglⅡand EcoRⅤ. All of the 3 phages belonged to family Siphoviridae, but with different genome fingerprint patterns. The physiological characteristics of the phages such as the optimal multiplicity of infection, the one-step growth curves and the sensitivity to temperature, pH, UV light, ether and chloroform were also tested. The results indicated that the phages had different biological characteristics and thus belonged to different strain types. This could contribute to the diversity of phages, the diagnosis and treatment of potential diseases caused by Klebsiella pneumoniae and typing of the relating Klebsiella bacteria.
2011, 33(4): 155-162.
Abstract:
CO2 perturbation experiments were carried out under the solar radiation with or without UV radiation (280~400 nm) in a temperature-controlled water bath to evaluate the coupled effects of CO2 and UVR on Phaeocystis globosa Scherffel that forms harmful algal blooms. The results show that both of high CO2 and UVR stress on the algae. The high concentration CO2 decreases a specific growth rate and the photochemical efficiency of the algae by up to 11.0% and 10.7%, respectively, and the UVR does further them 19.2% and 41.7%. With its cell density increasing, however, their inhibition to the alga was declining, and to minus value. UVR decreases its maximal relative electron transpert rate and photosynthetic efficiency by 14.1% and 21.0%, respectively, in ambient air, and additional 8.2% and 17.6% in the CO2-enriched. CO2 enrichment increases chlorophyll a, chlorophyll c and carotenoids by 4.6%,5.9% and 5.2%, respectively. The UVR increases carotenoids by 4.3%. The studies indicate that the high concentration CO2 aggravates the damage of UVR to the algae, which increaseds in carotenoids as a protective response.
CO2 perturbation experiments were carried out under the solar radiation with or without UV radiation (280~400 nm) in a temperature-controlled water bath to evaluate the coupled effects of CO2 and UVR on Phaeocystis globosa Scherffel that forms harmful algal blooms. The results show that both of high CO2 and UVR stress on the algae. The high concentration CO2 decreases a specific growth rate and the photochemical efficiency of the algae by up to 11.0% and 10.7%, respectively, and the UVR does further them 19.2% and 41.7%. With its cell density increasing, however, their inhibition to the alga was declining, and to minus value. UVR decreases its maximal relative electron transpert rate and photosynthetic efficiency by 14.1% and 21.0%, respectively, in ambient air, and additional 8.2% and 17.6% in the CO2-enriched. CO2 enrichment increases chlorophyll a, chlorophyll c and carotenoids by 4.6%,5.9% and 5.2%, respectively. The UVR increases carotenoids by 4.3%. The studies indicate that the high concentration CO2 aggravates the damage of UVR to the algae, which increaseds in carotenoids as a protective response.
2011, 33(4): 163-172.
Abstract:
2011, 33(4): 173-180.
Abstract:
2011, 33(4): 181-186.
Abstract:
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