The composition of gases trapped in olivine, orthopyroxene and clinopyroxene in Iherzolite xenoliths collected from different locations in eastern China has been measured by the vacuum stepped-heating mass spectrometr...The composition of gases trapped in olivine, orthopyroxene and clinopyroxene in Iherzolite xenoliths collected from different locations in eastern China has been measured by the vacuum stepped-heating mass spectrometry. These xenoliths are hosted in alkali basalts and considered as residues of partial melting of the upper mantle, and may contain evidence of mantle evolution. The results show that various kinds of fluid inclusions in Iherzolite xenoliths have been released at distinct times, which could be related to different stages of mantle evolution. In general, primitive fluids of the upper mantle (PFUM) beneath eastern China are dominated by H2, CO2 and CO, and are characterized by high contents of H2 and reduced gases. The compositions of PFUM are highly variable and related to tectonic settings. CO, CO2 and H2 are the main components of the PFUM beneath cratons; the PFUM in the mantle enriched in potassic metasomatism in the northern part of northeastern China has a high content of H2, while CO2 and SO2 are the dominant components of the PFUM in the Su-Lu-Wan (Jiangsu-Shandong-Anhui) region, where recycled crustal fluids were mixed with deeper mantle components. There are several fluids with distinct compositions beneath eastern China, such as primitive fluids of upper mantle (CO, CO2 and H2), partial melting fluids (CO2 and CO) and metasomatic fluids mixed with recycled crustal fluids (CO2, N2, SO2 and CH4) etc. Fluids of the upper mantle beneath the North China craton are different from that of the South China craton in total gases and chemical compositions: the contents of the reduced gases of the PFUM in the NCC are higher than those in the SCC.展开更多
The coupled ice- ocean model for the Bohai Sea is used for simulating the freezing, melting, and variation of ice cover and the heat bal- ance at the sea- ice, air- ice, and air- sea interfaces of the Bohai Sea during...The coupled ice- ocean model for the Bohai Sea is used for simulating the freezing, melting, and variation of ice cover and the heat bal- ance at the sea- ice, air- ice, and air- sea interfaces of the Bohai Sea during the entire winter in 1998 ̄1999 and 2000 ̄2001. The cou- pled model is forced by real time numerical weather prediction fields. The results show that the thermodynamic effects of atmosphere and ocean are very important for the evolvement of ice in the Bohai Sea, especially in the period of ice freezing and melting. Ocean heat flux plays a key role in the thermodynamic coupling. The simulation also presents the different thermodynamic features in the ice covered region and the marginal ice zone. Ice thickness, heat budget at the interface, and surface sea temperature, etc. between the two representative points are discussed.展开更多
To investigate the interaction between the tropical Pacific and China seas a variable-grid global ocean circulation model with fine grid covering the area from 20°S to 50°N and from 99° to 150°E is...To investigate the interaction between the tropical Pacific and China seas a variable-grid global ocean circulation model with fine grid covering the area from 20°S to 50°N and from 99° to 150°E is developed. Numerical computation of the annually cyclic circulation fields is performed. The results of the annual mean zonal currents and deep to abyssal western boundary currents in the equatorial Pacific Ocean are reported. The North Equatorial Current,the North Equatorial Countercurrent, the South Equatorial Current and the Equatorial Undercurrent are fairly well simulated. The model well reproduces the northward flowing abyssal western boundary current.From the model results a lower deep western boundary current east of the Bismarck-Solomon-New Hebrides Island chain at depths around 2 000 m has been found. The model results also show that the currents in the equatorial Pacific Ocean have multi-layer structures both in zonal currents and western boundary currents, indicating that the global ocean overturning thermohaline circulation appears of multi-layer pattern.展开更多
Based on TOPEX/Poseidon (T/P) and ERS-1 and 2 satellite altimeter data between October 1992 and December 2000, high frequency oscillations with periods less than 150 d are analyzed and their spatial distributions are ...Based on TOPEX/Poseidon (T/P) and ERS-1 and 2 satellite altimeter data between October 1992 and December 2000, high frequency oscillations with periods less than 150 d are analyzed and their spatial distributions are described. The ratio, instead of the energy itself, of the energy corresponding to certain frequency band from power spectrum relative to the total energy in the 20~143 d range is analyzed. The results show that the period of the most energetic oscillations in this band increases with latitude from about 1 month near the tropics to about 4 months near 30°, in agreement with the latitudinal dependency of the phase speed of westward propagating long Rossby waves,which dominate the variability in those latitudes.As a result,the global spatial distributions of the period of the dominant oscillations are largely zonal, with relatively small differences between different ocean basins. It suggests that the oscillations with periods around 60 d are mainly associated with planetary Rossby waves except the often regarded as tidal aliasing.展开更多
Five strains of antarctic bacteria producing extracellular low-temperature lipase are screened from seawater collectedby CTD during the Chinese 18th Antarctic Scientific Expedition. Their phylogenetic positions on the...Five strains of antarctic bacteria producing extracellular low-temperature lipase are screened from seawater collectedby CTD during the Chinese 18th Antarctic Scientific Expedition. Their phylogenetic positions on the basis ofamplification, comparison and analysis of almost complete 16S rDNA sequence are determined by neighbor-joininganalysis. Phylogenetic analysis indicates that all of these five strains belong to g-proteobacteria. The strains 11102 and 92 are classified as genus Pseudoalteromonas sp. and genus Psychrobacter sp. respectively. The strains 25101, 2221 and 1281 are classified as genus Moritella sp.展开更多
According to the earlier international studies on the coupled iceocean model and the hydrology, meteorology, and icefeatures in the Bohai Sea, a coupled iceocean model is developed based on the National Marine Environ...According to the earlier international studies on the coupled iceocean model and the hydrology, meteorology, and icefeatures in the Bohai Sea, a coupled iceocean model is developed based on the National Marine EnvironmentForecast Centers (NMEFC) numerical forecasting ice model of the Bohai Sea and the Princeton ocean model (POM).In the coupled model, the transfer of momentum and heat between ocean and ice is two-way, and the change of icethickness and concentration depends on heat budget not only at the surface and bottom of ice, but also at the surfaceof open water between ices. The dynamic and thermodynamic coupling process is expatiated emphatically. Somethermodynamic parameters are discussed as well.展开更多
The finite element method was used to simulate the currents of Jiaozhou Bay and the nearcoast areas, and then established the model of the transport and diffusion of suspended particulate matter there. The transport a...The finite element method was used to simulate the currents of Jiaozhou Bay and the nearcoast areas, and then established the model of the transport and diffusion of suspended particulate matter there. The transport and diffusion of dredged matter near the discharging field were estimated; and the results were used to analyze the effects of the suspended particulate matter on the marine environment.展开更多
On the basis of bathymetric data and other geological and geophysical data obtained during the first survey conducted by Chinese Mainland in the area off eastern Taiwan Island from May to June in 2000, the morphologic...On the basis of bathymetric data and other geological and geophysical data obtained during the first survey conducted by Chinese Mainland in the area off eastern Taiwan Island from May to June in 2000, the morphological features of the region, the tectonic control to the seafloor topography and their tectonic implication are studied and discussed. The results have revealed that both the slope zone of the Ryukyu arc and the Ryukyu Trench present a typical morphotectonic characteristics controlled by the trench-arc system in the West Pacific Ocean. At the slope of eastern Taiwan Island the isobathic lines parallel to the coastline and distribute densely in nearly N-S direction and the slope gradient of topography is large. Such a unique feature is attributed to the collision of the Luzon arc and Eurasia continent. In the Huatung Basin, turbidity fans and submarine canyons are well developed, the formations of which are mainly related to the steep topography of the slope of the Luzon arc and the abundant supply of sediments. These submarine canyons are controlled by basement highs and strike-slip faults. On eastern side and western side of the Gagua Ridge, both the water depth and morphological features are different, but the basement of Gagua Ridge belongs to the Huatung Basin. The eastern side of the Gagua Ridge (123°12′E) corresponds to the boundary of two plates with different ages. In the West Philippine Basin, linear ridges and troughs in a NW trending are identified, which are dissected by a NE trending transform fault. According to the seafloor topography features, the direction of the transform fault and the magnetic anomaly lineations, the seafloor of this region was formed during 60-45 Ma B. P. when the West Philippine Basin was spreading along NE-SW relative to the present orientation.展开更多
The fractal characteristics of tidal creeks in the Gaizhou Beach are analyzed based on high-resolution images fusionof Landsat TM and ERS2, and then the graphic models and characteristics of converse information tree ...The fractal characteristics of tidal creeks in the Gaizhou Beach are analyzed based on high-resolution images fusionof Landsat TM and ERS2, and then the graphic models and characteristics of converse information tree of tidalcreeks in the Gaizhou Beach are established. A calculation model is established based on the above results, and at thesame time, quantitative calculation of the evolution characteristics and the diversity between the northern and thesouthern parts of the Gaizhou Beach is carried out. By the supervised classification of these images, distribution andareas of high tidal flats, middle tidal flats and low tidal flats in the Gaizhou Beach are studied quantitatively, and imagecharactistics of seashell habitats in the Gaizhou Beach and the correlation between mudflat distribution and seashellhabitats are studied. At last, the engineering problems in the Gaizhou Beach are discussed.展开更多
Six genes encoding light-harvesting complex (LHC) protein have been characterized in the multicellular red alga Griffithsia japonica EST analysis. Three of them were full sequences while others were partial sequences ...Six genes encoding light-harvesting complex (LHC) protein have been characterized in the multicellular red alga Griffithsia japonica EST analysis. Three of them were full sequences while others were partial sequences with 3'-UTRs. The cleavage sites between signal peptide and mature LHC protein were analyzed on these three full sequences. The sequence characteristics, calculated molecular weights and isoelectric point (pI) values and hydrophobicity of the mature proteins were deduced and analyzed. Comparing the LHC sequences of G. japonica with higher plant, Chlorophyta, chromophytes and other red algae, the high conservation of the chlorophyll (Chl) binding site among chromophytes and red algae were revealed. Phylogenetic analysis on LHC proteins from higher plant, green algae, euglena, brown algae, diatom, cryptomonad, Raphidophyte and red algae reveals that (1) there are two distinct groups of Chl a/b and Chl a/c -binding LHC; (2) Chl a binding proteins of red algae share greater similarities with the Chl a/c-binding proteins of the chromophytes and dinoflagellate than with the Chl a/b - binding proteins of the green algae and higher plants; (3) chromophyte's LHC is supposed to be evolved from red algae LHC.展开更多
An analysis of seismic data obtained through a cable route survey starting from the Qingdao coast to offshore has determined nine seismic units since Late Pleistocene. Correlation of the seismic data with Borehole Hj2...An analysis of seismic data obtained through a cable route survey starting from the Qingdao coast to offshore has determined nine seismic units since Late Pleistocene. Correlation of the seismic data with Borehole Hj2 confirms three eustatic events that occurred during the Late Quaternary and formed terrestrial units 2, 5 and 7. At the low sea level stage, paleo rivers highly developed, eroded previous strata, formed paleo valley, and left materials.展开更多
The effects of the artificial-diversion of the Yellow River Mouth for extensive petroleum exploration beginning in August 1996 on the morphology of the mud flat coast are discussed. Changes in the morphology of the co...The effects of the artificial-diversion of the Yellow River Mouth for extensive petroleum exploration beginning in August 1996 on the morphology of the mud flat coast are discussed. Changes in the morphology of the coastal zone were monitored during the period from 1996 to 2000. A Golden Software system was used to calculate the differential surfaces between the surveys in order to investigate the local patterns of accretion and erosion and to determine the volume changes between consecutive surveys. Volumetric studies showed that the net accretion in the study period was about 1.7×10 8 m 3. Between July 1996 and October 1996, a time interval characterized by intense runoff, an accumulation of about 4×10 8 m 3 occurred. In the period from October 1996 to October 1998, a period of diminution in runoff and sediment supply in the upstream, an erosion of 8.9×10 7 m 3 occurred, indicating sediment starvation of the area. Between October 1998 and October 2000, due to an inadequate supply of runoff and sediment, about 1.4×10 8 m 3 of sediments was eroded and transported offshore.展开更多
The species and characteristics of Radiolaria in the surface sediments were systematcally investigated in the sea east of Taiwan Island. One hundred and seventy-eight species of Radiolaria (including 21 unidentified s...The species and characteristics of Radiolaria in the surface sediments were systematcally investigated in the sea east of Taiwan Island. One hundred and seventy-eight species of Radiolaria (including 21 unidentified species) have been identified in the surface sediments, and they belong to 2 orders, 34 families and 101 genera. Among them there are 19 families, 70 genera, 134 species of Spumellaria and 15 families, 31 genera, 44 species of Nassellaria. Of the 178 species of Radiolaria, the individual number of Spumellaria amounts to 88.1 % of the total individual number, and that of Nassellaria amounts to 11.9% of the total individual number. It is shown that most of the dominant species belong to the tropical and subtropical dominant species and are brought into the area mainly by the Kuroshio, and some affecting factors including the submarine topography, submarine sediments, upwelling current east of Taiwan Island and carbonate dissolution play a secondary role in forming the Radiolaria distributions.展开更多
Based on analyses of more than 600 surface sediment samples together with large amounts of previous sedimeutologic and hydrologic data, the characteristics of modern sedimentary environments and dynamic depositional s...Based on analyses of more than 600 surface sediment samples together with large amounts of previous sedimeutologic and hydrologic data, the characteristics of modern sedimentary environments and dynamic depositional systems in the southern Yellow Sea (SYS) are expounded, and the controversial formation mechanism of muddy sediments is also discussed. The southern Yellow Sea shelf can be divided into low-energy sedimentary environment and high-energy sedimentary environment; the lowenergy sedimentary environment can be further divided into cyclonic and anticyclonic ones, and the high-energy environment is subdivided into high-energy depositional and eroded environments. In the shelf low-energy environments,there developed muddy depositional system. In the central part of the southern Yellow Sea, there deposited the cold eddy sediments under the actions of a meso-scale cyclonic eddy (cold eddy), and in the southeast of the southern Yellow Sea, an anticyclonic eddy muddy depositional system (warm eddy sediment) was formed. These two types of sediments showed evident differences in grain size, sedimentation rate,sediment thickness and mineralogical characteristics. The high-energy environments were covered with sandy sediments on seabed; they appeared mainly in the west, south and northeast of the southern Yellow Sea. In the high-energy eroded environment, large amounts of sandstone gravels were distributed on seabed. In the high-energy depositional environment, the originally deposited fine materials (including clay and fine silt) were gradually re-suspended and then transported to a low-energy area to deposit again. In this paper, the sedimentation model of cyclonic and anticyclonic types of muddy sediments is established, and a systematic interpretation for the formation cause of muddy depositional systems in the southern Yellow Sea is given.展开更多
The concentrations of total suspended matter (TSM) and the compositions of organic stable carbon isotopes of TSM and bottom sediments were analyzed to study the sources of TSM and sediments and the transportation proc...The concentrations of total suspended matter (TSM) and the compositions of organic stable carbon isotopes of TSM and bottom sediments were analyzed to study the sources of TSM and sediments and the transportation processes. For this study, 284 TSM samples and 64 sediment ones taken from 67 stations along 7 transects and in 5 layers were collected in the southern Yellow Sea on the cruise in May, 1998. The main sediment transportation pattern in the southern Yellow Sea was obtained by analyzing the distribution characteristics of TSM concentration and particulate organic carbon δ^13C values. It was confirmed from the pattern that the bottom layer plays a more important role than the surface one in the transportation processes of terrigenous material to the central deep-water area of the southern Yellow Sea. The Yellow Sea circulation is an important control factor in determining the sediment transportation pattern in the southern Yellow Sea. The carbon isotope signals of sedimentary organic matter confirmed that the main material in sediments with high sedimentation rate in the Shandong subaqueous delta originated from the modern Yellow River.The terrigenous sediments in the deep-water area of the southern Yellow Sea are mainly from the abandoned Yellow River and the modern Yellow River, and a small portion of them are from the modern Yangtze material. The amount of terrigenous material from Korean Peninsula and its influence range are relatively limited. The conclusions derived from TSM and stable carbon isotopes were further confirmed by another independent material source tracer--PAHs.展开更多
基金the Natural Science Foundation of China(grant 40273009).
文摘The composition of gases trapped in olivine, orthopyroxene and clinopyroxene in Iherzolite xenoliths collected from different locations in eastern China has been measured by the vacuum stepped-heating mass spectrometry. These xenoliths are hosted in alkali basalts and considered as residues of partial melting of the upper mantle, and may contain evidence of mantle evolution. The results show that various kinds of fluid inclusions in Iherzolite xenoliths have been released at distinct times, which could be related to different stages of mantle evolution. In general, primitive fluids of the upper mantle (PFUM) beneath eastern China are dominated by H2, CO2 and CO, and are characterized by high contents of H2 and reduced gases. The compositions of PFUM are highly variable and related to tectonic settings. CO, CO2 and H2 are the main components of the PFUM beneath cratons; the PFUM in the mantle enriched in potassic metasomatism in the northern part of northeastern China has a high content of H2, while CO2 and SO2 are the dominant components of the PFUM in the Su-Lu-Wan (Jiangsu-Shandong-Anhui) region, where recycled crustal fluids were mixed with deeper mantle components. There are several fluids with distinct compositions beneath eastern China, such as primitive fluids of upper mantle (CO, CO2 and H2), partial melting fluids (CO2 and CO) and metasomatic fluids mixed with recycled crustal fluids (CO2, N2, SO2 and CH4) etc. Fluids of the upper mantle beneath the North China craton are different from that of the South China craton in total gases and chemical compositions: the contents of the reduced gases of the PFUM in the NCC are higher than those in the SCC.
基金supported by the National Natural Science Foundation of China under contract Nos 40233032 and 40376006the National High Technolo-gy Research and Development Program of China(“863")under contract Nos 2002AA639340 and 2001 AA631070the Principal Project under contract Nos 2001DIA50040 and 2001CB7l1006.
文摘The coupled ice- ocean model for the Bohai Sea is used for simulating the freezing, melting, and variation of ice cover and the heat bal- ance at the sea- ice, air- ice, and air- sea interfaces of the Bohai Sea during the entire winter in 1998 ̄1999 and 2000 ̄2001. The cou- pled model is forced by real time numerical weather prediction fields. The results show that the thermodynamic effects of atmosphere and ocean are very important for the evolvement of ice in the Bohai Sea, especially in the period of ice freezing and melting. Ocean heat flux plays a key role in the thermodynamic coupling. The simulation also presents the different thermodynamic features in the ice covered region and the marginal ice zone. Ice thickness, heat budget at the interface, and surface sea temperature, etc. between the two representative points are discussed.
基金This study is supported by the National Natural Sci-ence Foundation of China under contract No.40136010the Major State Basic Research Program of China under contract No.G1999043808the Youth Fund of National“863”Project of China under contract No.2002AA639350.
文摘To investigate the interaction between the tropical Pacific and China seas a variable-grid global ocean circulation model with fine grid covering the area from 20°S to 50°N and from 99° to 150°E is developed. Numerical computation of the annually cyclic circulation fields is performed. The results of the annual mean zonal currents and deep to abyssal western boundary currents in the equatorial Pacific Ocean are reported. The North Equatorial Current,the North Equatorial Countercurrent, the South Equatorial Current and the Equatorial Undercurrent are fairly well simulated. The model well reproduces the northward flowing abyssal western boundary current.From the model results a lower deep western boundary current east of the Bismarck-Solomon-New Hebrides Island chain at depths around 2 000 m has been found. The model results also show that the currents in the equatorial Pacific Ocean have multi-layer structures both in zonal currents and western boundary currents, indicating that the global ocean overturning thermohaline circulation appears of multi-layer pattern.
文摘Based on TOPEX/Poseidon (T/P) and ERS-1 and 2 satellite altimeter data between October 1992 and December 2000, high frequency oscillations with periods less than 150 d are analyzed and their spatial distributions are described. The ratio, instead of the energy itself, of the energy corresponding to certain frequency band from power spectrum relative to the total energy in the 20~143 d range is analyzed. The results show that the period of the most energetic oscillations in this band increases with latitude from about 1 month near the tropics to about 4 months near 30°, in agreement with the latitudinal dependency of the phase speed of westward propagating long Rossby waves,which dominate the variability in those latitudes.As a result,the global spatial distributions of the period of the dominant oscillations are largely zonal, with relatively small differences between different ocean basins. It suggests that the oscillations with periods around 60 d are mainly associated with planetary Rossby waves except the often regarded as tidal aliasing.
文摘Five strains of antarctic bacteria producing extracellular low-temperature lipase are screened from seawater collectedby CTD during the Chinese 18th Antarctic Scientific Expedition. Their phylogenetic positions on the basis ofamplification, comparison and analysis of almost complete 16S rDNA sequence are determined by neighbor-joininganalysis. Phylogenetic analysis indicates that all of these five strains belong to g-proteobacteria. The strains 11102 and 92 are classified as genus Pseudoalteromonas sp. and genus Psychrobacter sp. respectively. The strains 25101, 2221 and 1281 are classified as genus Moritella sp.
基金the National Natural Science Foundation of China under contract Nos40233032 , 40376006the National High Technology Research and Development Program(863) of China under contract Nos 2002AA639340 , 2001AA631070 the Principal Project under contract Nos2001DIA50040 , 2001CB711006.
文摘According to the earlier international studies on the coupled iceocean model and the hydrology, meteorology, and icefeatures in the Bohai Sea, a coupled iceocean model is developed based on the National Marine EnvironmentForecast Centers (NMEFC) numerical forecasting ice model of the Bohai Sea and the Princeton ocean model (POM).In the coupled model, the transfer of momentum and heat between ocean and ice is two-way, and the change of icethickness and concentration depends on heat budget not only at the surface and bottom of ice, but also at the surfaceof open water between ices. The dynamic and thermodynamic coupling process is expatiated emphatically. Somethermodynamic parameters are discussed as well.
文摘The finite element method was used to simulate the currents of Jiaozhou Bay and the nearcoast areas, and then established the model of the transport and diffusion of suspended particulate matter there. The transport and diffusion of dredged matter near the discharging field were estimated; and the results were used to analyze the effects of the suspended particulate matter on the marine environment.
文摘On the basis of bathymetric data and other geological and geophysical data obtained during the first survey conducted by Chinese Mainland in the area off eastern Taiwan Island from May to June in 2000, the morphological features of the region, the tectonic control to the seafloor topography and their tectonic implication are studied and discussed. The results have revealed that both the slope zone of the Ryukyu arc and the Ryukyu Trench present a typical morphotectonic characteristics controlled by the trench-arc system in the West Pacific Ocean. At the slope of eastern Taiwan Island the isobathic lines parallel to the coastline and distribute densely in nearly N-S direction and the slope gradient of topography is large. Such a unique feature is attributed to the collision of the Luzon arc and Eurasia continent. In the Huatung Basin, turbidity fans and submarine canyons are well developed, the formations of which are mainly related to the steep topography of the slope of the Luzon arc and the abundant supply of sediments. These submarine canyons are controlled by basement highs and strike-slip faults. On eastern side and western side of the Gagua Ridge, both the water depth and morphological features are different, but the basement of Gagua Ridge belongs to the Huatung Basin. The eastern side of the Gagua Ridge (123°12′E) corresponds to the boundary of two plates with different ages. In the West Philippine Basin, linear ridges and troughs in a NW trending are identified, which are dissected by a NE trending transform fault. According to the seafloor topography features, the direction of the transform fault and the magnetic anomaly lineations, the seafloor of this region was formed during 60-45 Ma B. P. when the West Philippine Basin was spreading along NE-SW relative to the present orientation.
基金This study was supported by the Project of“863”Marine Monitor of Hi-Tech Research and Development Program of China under contract No.2003AA604040.
文摘The fractal characteristics of tidal creeks in the Gaizhou Beach are analyzed based on high-resolution images fusionof Landsat TM and ERS2, and then the graphic models and characteristics of converse information tree of tidalcreeks in the Gaizhou Beach are established. A calculation model is established based on the above results, and at thesame time, quantitative calculation of the evolution characteristics and the diversity between the northern and thesouthern parts of the Gaizhou Beach is carried out. By the supervised classification of these images, distribution andareas of high tidal flats, middle tidal flats and low tidal flats in the Gaizhou Beach are studied quantitatively, and imagecharactistics of seashell habitats in the Gaizhou Beach and the correlation between mudflat distribution and seashellhabitats are studied. At last, the engineering problems in the Gaizhou Beach are discussed.
文摘Six genes encoding light-harvesting complex (LHC) protein have been characterized in the multicellular red alga Griffithsia japonica EST analysis. Three of them were full sequences while others were partial sequences with 3'-UTRs. The cleavage sites between signal peptide and mature LHC protein were analyzed on these three full sequences. The sequence characteristics, calculated molecular weights and isoelectric point (pI) values and hydrophobicity of the mature proteins were deduced and analyzed. Comparing the LHC sequences of G. japonica with higher plant, Chlorophyta, chromophytes and other red algae, the high conservation of the chlorophyll (Chl) binding site among chromophytes and red algae were revealed. Phylogenetic analysis on LHC proteins from higher plant, green algae, euglena, brown algae, diatom, cryptomonad, Raphidophyte and red algae reveals that (1) there are two distinct groups of Chl a/b and Chl a/c -binding LHC; (2) Chl a binding proteins of red algae share greater similarities with the Chl a/c-binding proteins of the chromophytes and dinoflagellate than with the Chl a/b - binding proteins of the green algae and higher plants; (3) chromophyte's LHC is supposed to be evolved from red algae LHC.
基金supported by the State‘863’Plan(No.2001AA602025)
文摘An analysis of seismic data obtained through a cable route survey starting from the Qingdao coast to offshore has determined nine seismic units since Late Pleistocene. Correlation of the seismic data with Borehole Hj2 confirms three eustatic events that occurred during the Late Quaternary and formed terrestrial units 2, 5 and 7. At the low sea level stage, paleo rivers highly developed, eroded previous strata, formed paleo valley, and left materials.
基金supported by the National High Technology Research and Development Program of China(863 Program)(Grant Number 2002AA639370).
文摘The effects of the artificial-diversion of the Yellow River Mouth for extensive petroleum exploration beginning in August 1996 on the morphology of the mud flat coast are discussed. Changes in the morphology of the coastal zone were monitored during the period from 1996 to 2000. A Golden Software system was used to calculate the differential surfaces between the surveys in order to investigate the local patterns of accretion and erosion and to determine the volume changes between consecutive surveys. Volumetric studies showed that the net accretion in the study period was about 1.7×10 8 m 3. Between July 1996 and October 1996, a time interval characterized by intense runoff, an accumulation of about 4×10 8 m 3 occurred. In the period from October 1996 to October 1998, a period of diminution in runoff and sediment supply in the upstream, an erosion of 8.9×10 7 m 3 occurred, indicating sediment starvation of the area. Between October 1998 and October 2000, due to an inadequate supply of runoff and sediment, about 1.4×10 8 m 3 of sediments was eroded and transported offshore.
文摘The species and characteristics of Radiolaria in the surface sediments were systematcally investigated in the sea east of Taiwan Island. One hundred and seventy-eight species of Radiolaria (including 21 unidentified species) have been identified in the surface sediments, and they belong to 2 orders, 34 families and 101 genera. Among them there are 19 families, 70 genera, 134 species of Spumellaria and 15 families, 31 genera, 44 species of Nassellaria. Of the 178 species of Radiolaria, the individual number of Spumellaria amounts to 88.1 % of the total individual number, and that of Nassellaria amounts to 11.9% of the total individual number. It is shown that most of the dominant species belong to the tropical and subtropical dominant species and are brought into the area mainly by the Kuroshio, and some affecting factors including the submarine topography, submarine sediments, upwelling current east of Taiwan Island and carbonate dissolution play a secondary role in forming the Radiolaria distributions.
文摘Based on analyses of more than 600 surface sediment samples together with large amounts of previous sedimeutologic and hydrologic data, the characteristics of modern sedimentary environments and dynamic depositional systems in the southern Yellow Sea (SYS) are expounded, and the controversial formation mechanism of muddy sediments is also discussed. The southern Yellow Sea shelf can be divided into low-energy sedimentary environment and high-energy sedimentary environment; the lowenergy sedimentary environment can be further divided into cyclonic and anticyclonic ones, and the high-energy environment is subdivided into high-energy depositional and eroded environments. In the shelf low-energy environments,there developed muddy depositional system. In the central part of the southern Yellow Sea, there deposited the cold eddy sediments under the actions of a meso-scale cyclonic eddy (cold eddy), and in the southeast of the southern Yellow Sea, an anticyclonic eddy muddy depositional system (warm eddy sediment) was formed. These two types of sediments showed evident differences in grain size, sedimentation rate,sediment thickness and mineralogical characteristics. The high-energy environments were covered with sandy sediments on seabed; they appeared mainly in the west, south and northeast of the southern Yellow Sea. In the high-energy eroded environment, large amounts of sandstone gravels were distributed on seabed. In the high-energy depositional environment, the originally deposited fine materials (including clay and fine silt) were gradually re-suspended and then transported to a low-energy area to deposit again. In this paper, the sedimentation model of cyclonic and anticyclonic types of muddy sediments is established, and a systematic interpretation for the formation cause of muddy depositional systems in the southern Yellow Sea is given.
文摘The concentrations of total suspended matter (TSM) and the compositions of organic stable carbon isotopes of TSM and bottom sediments were analyzed to study the sources of TSM and sediments and the transportation processes. For this study, 284 TSM samples and 64 sediment ones taken from 67 stations along 7 transects and in 5 layers were collected in the southern Yellow Sea on the cruise in May, 1998. The main sediment transportation pattern in the southern Yellow Sea was obtained by analyzing the distribution characteristics of TSM concentration and particulate organic carbon δ^13C values. It was confirmed from the pattern that the bottom layer plays a more important role than the surface one in the transportation processes of terrigenous material to the central deep-water area of the southern Yellow Sea. The Yellow Sea circulation is an important control factor in determining the sediment transportation pattern in the southern Yellow Sea. The carbon isotope signals of sedimentary organic matter confirmed that the main material in sediments with high sedimentation rate in the Shandong subaqueous delta originated from the modern Yellow River.The terrigenous sediments in the deep-water area of the southern Yellow Sea are mainly from the abandoned Yellow River and the modern Yellow River, and a small portion of them are from the modern Yangtze material. The amount of terrigenous material from Korean Peninsula and its influence range are relatively limited. The conclusions derived from TSM and stable carbon isotopes were further confirmed by another independent material source tracer--PAHs.