最新刊期
期 39 ， 1997
- 摘要：Wave groups as natural phenomenon often accompanying sea waves have enormous destructive power. So, studies on them have aroused keen interest, especially in the ocean engineering community. Most past studies mainly focused on their statistical properties, rarely on their structural features. In this work, a dataset on typical wave groups was chosen to analyze the characteristics of wave group spectra by the gradual reduction of sampling numbers, using Fast Fourier Transform (FFT) and Maximum Entropy Method (MEM). The results indicated that the wave group spectrum obviously differed from common wave spectrum. The frequency range of wave group spectrum becomes narrow obviously and the peak value of its spectrum becomes large obviously. The whole spectral shape is similar to δ function. Also, when the many component waves the wave groups contain gradually reduce to one large component wave, the analysis results showed the features of two peak spectrum. The spectra of typical wave groups consist of two frequency components with approximately the same frequencies but different amplitudes. That is to say, the typical wave group is the superposition resultant of two train waves whose frequencies are nearly the same and amplitudes are different, just like the "BEAT" in physics-which is the resultant of two simple harmonic motions with identical motion direction, different amplitudes and periods. This study demonstrated that wave group spectrum is of the shape of δ function, which has important significance for engineering design and deserve our great attention.
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发布时间：2023-07-07 - 摘要：In this work, using the sea temperature data on the western Yellow Sea during 1959-1995, the main features of long-term, stage and interdecadal variations in Qingdao Cold Water Mass (QCWM) strength were studied by using regression analysis and maximum entropy method. The QCWM'S interannual change and possible causes were discussed using the air temperature data in North China. The results showed that the QCWM strengthened during 1959-1975 and weakened during 1976-1995; and that the stage change in the QCWM'S strength displayed regular low-frequency oscillation. The interannual changes in the water mass strength were associated with the ENSO cycle, and were affected by winter (February) air-temperature changes in the coastal area of the northern Shandong Peninsula.
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发布时间：2023-07-07 - 摘要：About 50-year data on water and sediment discharge of the Changjiang River at the Dotong gauge, and observation data on suspended matter concentration collected in 22 cruises in the East China Sea (ECS) were analyzed to study the tendency of water and sediment discharge of the Changjiang River and the temporal variability of suspended matter concentration in the ECS. From the 1950s up to now, the annually average water discharge of the Changjiang River was not obviously variable, while sediment discharge had declined remarkably since 1986 because of the construction of the Gezhou Dam. Suspended matter concentration in the ECS having obviously decreasing trend with time, was consistent with the variability of sediment discharge of the Changjiang River. Furthermore, the reduction of suspended matter concentration at the Estuary and its adjacent sea area was more than that on the continental shelf. The decrease of suspended matter concentration in the sea was not to the same extent as that in the Changjiang River, because the factors that controlled suspended matter concentration in the studied sea area were the material source and the hydrodynamic conditions when in-situ observations were being carried out. Especially in winter, the hydrodynamic conditions sometimes would become the major factor controlling suspended matter concentration.
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发布时间：2023-07-07 - 摘要：The circulation, tide and tide current in the Bohai Sea, Yellow Sea and East China Sea were relatively successfully simulated by POM (Princeton Ocean Model). Then after the governing equation of suspended matter transport was added into POM, and with due consideration of the mechanism of the sedimentation and re-suspension, the transport, dispersion, sedimentation and erosion of suspended matter affected by circulation and tide current were simulated. Simulated results on the temporal and spatial distribution of total suspended matter concentration revealed and further proved that the seasonal characteristics of suspended matter transport were: storage in summer and autumn; transport in winter and spring in the East China Seas. Shelf circulation has crucial influence on long-term suspended matter transport. The finer the grain size of suspended matter was, the farther it dispersed. The simulated distribution of surface sediment accorded with that measured; and the simulated settling velocity on the mud off Zhejiang coast is similar to the measured. The calculated result of suspended matter exchange showed that net flux of suspended matter from the Yellow Sea to the East China Sea was 5.0×107 tons every year, especial autumn and winter; the net flux from the Bohai Sea to the Yellow Sea was 1.5×107 tons every year, about 2% of total suspended matter derived from the Yellow River.
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发布时间：2023-07-07 - 摘要：Thermohaline and circulation structures in the northwestern East China Sea adjacent to the Changjiang River estuary are determined mainly by the characteristics, variations and interactions of the Changjiang River Diluted Water (CDW) and the Taiwan Warm Current Water (TWCW). In this paper, data gathered from 2 surveys in July-August 2001 and January 2002 were used to study the water mass distributions in summer and winter in the study area. Observations during 5 investigations from 1987 to 2001 (summer of 1987, 1998 and 2000, winter of 1997 and 2001), and historcal data from 1958 to 1982 along 28°N, 29°N and 30°N sections were used to discuss the correlationship and interannual variations of the CDW and the TWCW. Results showed that, in the summer of 2001, the CDW turned to the northeast at about 122.5 E°. The TWCW reached the latitude of the Changjiang River estuary at depth, and caused upwelling off the Zhejiang coast. Especially, the deep water of the TWC was found to extend to the north of 31°N. Temperature above the thermocline was about 2-4℃ higher than climatological values.
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发布时间：2023-07-07 - 摘要：This paper based sound signal data recorded in the Antarctic, reports preliminary results of study on the sound signal characteristics of various acoustical behaviours of the penguin Pygoscelis Adeliae. A Pygoscelis Adeliae emits different acoustical signals consisting of a series of pulses and continuous wave. Among these, the signal “ea” of a male penguin and "a" of a juvenile penguin are all composed of pulses, the signals "ji" of an infant penguin; "a" of a juvenile penguin and “ga" of an adult penguin all consist of a series of pulses, and the signal "a" of an adult penguin taking care of some juvenile penguins is composed of continuous waves.
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发布时间：2023-07-07 - 摘要：Based on data surveyed from 1950 to 1993 at Datong station at lower reach of the Changjiang River and surveyed from 1950 to 1998 at Lijin station at lower reach of the Yellow River, the characteristics of the two river’s water and suspended sediments flux were analyzed. The results showed that there are great differences on their characteristics of water and suspended sediments flux between two big rivers, their extension velocities of delta are different too for the different climate conditions, material constitute on the ground, the geological and geomorphologic characteristics, the position of their estuary, the hydrodynamic condition in sea area near their deltas and the impact from human activities. The total water and sediment resources and their annual distributed pattern are the key factors in the utilization and harnessing the Yellow River.关键词：water and suspended sediments flux;annual distributed pattern;the Changjiang River and the Yellow River
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发布时间：2023-07-07 - 摘要：The distribution of the contents of total particulate amino acids (ΣPAA) in surface seawater of Bohai Bay, Yellow River Estuary and Changjiang (Yangtze) River Estuary were studies by R/V “Golden Star No. 2” from 1982 to 1984. Near Bohai Bay, the contents of ΣPAA in surface seawater were lower(60-80μg/L) than those of most stations outside the Bay, where ΣPAA, were> 100μg/L. Near the Yellow River Estuary region exhibited higher contents of ΣPAA, reaching 600μg/L and even at other stations outside the estuary ΣPAA contents were 100μg/L or > 100μg/L. At several stations of the inland of Changjiang (Yangtze) River the contents of ΣPAA were about 200μg/L and decreased to 186-90μg/L in the lower course of the river. But near the region of Zhoushan Island they again increased to 200μg/L. It is probable that the increase of ΣPAA contents was due to the high density of growing plankton and high contents of organic substances there.关键词：total particulate amino acids;distribution
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发布时间：2023-07-07 - 摘要：The components and contents of particulate amino acids (PAA) in surface seawater were studies by R/V "Science No.1" in July and August of 1981 and July and August of 1982, at more than 20 stations in the East China Sea including the Cheju Do sea area, southeast section from the Changjiang Estuary to the Okinawa Trench and Fujian Province seawaters. The results obtained were as follows: 1. At Station 501 outside the Changjiang estuary, the contents of total particulate amino acids (ΣPAA) amounted to 129μg/L. In the open sea beyond the estuary ΣPAA decreased to 30-70μg/L; and at station 704 in seawater of 1680m depth it decreased to even 12μg/L. 2. In the Kuroshio Valley, the contents of ΣPAA in surface seawater and in 50 m depth water were higher than those at stations 101, 304, and 701 in greater depth water. 3. Most stations in the Cheju Do sea area had ΣPAA contents of 30 to 60μg/L; except for stations 1-3, in which ΣPAA contents reached to 112μg/L, probably because of the influence of Changjiang diluted water coming north from the Changjiang Estuary.
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发布时间：2023-07-07 - 摘要：As the main source and sink of global carbon, marine sediments play an important role in the marine carbon cycle. This paper reviews the progress of recent years research on the marine carbon cycling in marine sediments. The main forms of carbon in marine sediments are organic carbon and inorganic carbon, which come mainly from river transport, marine autogenesis and atmosphere settlement. The ratios of C/N and δ13C could be used to determine the carbon origin. The dissolved carbon in seawater could be converted to particulate carbon through biological process, such as photosynthesis, and reef building process. Ninety percent of particulate carbon participating in the carbon recycling process are released in the settling process; less than 10% are deposited on the bottom sediments, still less are imbedded. Early diagenesis occurs after carbon is transported to sediments from seawater. Organic carbon is oxidized by oxygen, nitrate, oxides of Fe and Mn, sulfate, then finally become CO2 and other products. CO2 could cause change of PH value in sediments, and then destroy the balance of carbonate, and result in dissolution or precipitation of carbonate, Carbon may be transferred into seawater and take part in the recycling process, wherein biological processes play an important role. The complex biogeochemistry processes in the compound system of sediment and seawater control the carbon cycle in marine.
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发布时间：2023-07-07 - 摘要：Chitosan is a potential polysaccharide resource owing to its specific structure and properties. However, since chitosan itself is insoluble in water at neutral PH, the application of chitosan is quite limited. Therefore, chemical modification of chitosan to make it water-soluble materials is of prime importance for making novel biomaterials. This paper mainly expounds on the chemical modification of chitosan, such as N-acetylated chitosan, hydroxyacylated chitosan, sulfated chitosan, and so on. This paper can serve as reference for further development of chitosan.
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发布时间：2023-07-07 - 摘要：Carbohydrates are important structural and functional moieties of glycoproteins and glycolipids. Many important biological processes, such as development, immunology, cancer metastasis, etc. are mediated by the carbohydrates moieties of glycoconjugates. Oligosaccharides from most biological sources are of considerable complexity and variety. Understanding the precise roles they play in biological processes often required their isolation, detailed structural analyses and usage in functional assays. Generally oligosaccharides lack chromophore groups, which increase the difficulty of oligosaccharides structure analysis. Now a complete analysis of a carbohydrate oligomer is one of the foremost and compelling challenges in structural biology. We reviewed 28 references on the methods for solation and structure determination for oligosaccharides.
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发布时间：2023-07-07 - 摘要：Biochemical and morphological parameters of laboratory-reared developing eggs and larvae of bastard halibut (Paralichthys olivaceus) were measured for oxygen uptake, ammonia excretion, contents of free amino acids (FAA), fatty acids (FA) and accumulated ammonium, and volume of yolk-sac and oil globule at(17.4士0.3)℃。 The bastard halibut had an obvious ammonium cumulation during its egg developmental stage. When hatching, the cumulated ammonia were released. Free amino acids (FAA) acted as the most important energy source during the egg developmental stage, and after hatching fatty acids (FA) of neutral lipids in the oil globule was used as the main energy substrate. Before start-feeding, protein began to supply energy base to some extent. Based on our results and accumulated information, it is concluded that the most important energy source has species-specialty in fish developmental biology and its bioenergetics and further research on this theme is urgent for interpretation of early life history pattern during recruitment of marine fishes.
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发布时间：2023-07-07 - 摘要：In vitro experiments showed that cell movements are motivated by active actin nucleation and branching at the motile cell’s leading edge. Cortactin and Arp2/3 complex play important roles in this process. Here, we report the expression pattern of these proteins in the gastrula of Amphioxus (Branchiostoma belcheri tsingtaoense) with the method of whole-mount antibody staining; which was indicated that cortactin and Arp2/3 complex were colocalized and mediated the invagination movement during amphioxus gastrulation; and that they appeared in mesendoderm cells but not in ectoderm cells. In addition, a specific stained area near the vegetable pole was detected prior to the initiation of gastrulation.
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发布时间：2023-07-07 - 摘要：In order to investigate nutrient limitation of phytoplankton in natural marine ecosystems, in-situ nutrient enrichment experiments with nitrate, ammonium, phosphate and iron addition were conducted in Jiaozhou Bay in August November, 1999 and February May and August, 2000. Jiaozhou Bay, surrounded by Qingdao city and with area of 390 km2 and mean depth of 7m is an eutrophic coastal bay. The concentrations of nitrate, ammonium and phosphate were 1.98, 8.01and 1.38 μmom/L in the 1999s. DIN: P molar ratio was almost always over 16 (the Redfield ratio, also called “geochemically balanced”) in all seasons. Five nutrient enrichment experiments were conducted to investigate nutrient limitation on phytoplankton. Size-fractionated chlorophyll-a results showed that netphytoplankton (20-200μmom/L) showed most significant response to N addition; nanophytoplankton (2-200μmom/L) showed significant response to P addition, but N addition also stimulated their growth; picophytoplankton (<2μmom/L) showed positive response to N or P addition, but this response was not more significant than that of netplankton or nanoplankton. N probably Limited phytoplankton growth in summer, but P and N nutrient could phytoplankton growth in other seasons in Jiaozhou Bay.关键词：nutrient limitation;Jiaozhou Bay
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发布时间：2023-07-07 - 摘要：Skeletonema costatum is the dominant phytoplankton in Changjiang Estuary. Blooming of Skeletonema costatum arose several times in Changjiang Estuary in recent years. In order to study the relationship between concentration of nitrate and the Skeletonema costatum blooming. We studied the growth of Skeletonema costatum in different concentration of nitrate. Growth rate, PH, dissolved organic carbon (DOC) and maximal uptake rates of nutrients were educed through the experiment. The results showed that low nitrate concentration limited the growth of Skeletonema costatum although the concentration of phosphate was high. The optimum N/P ratio was 15.7 among different N/P ratios tested in the experiment. The closer the N/P ratio was to the Redfield ratio 16:1, the higher was the growth rate of phytoplankton. The growth rate and concentration of cell, when N/P ratio was over 15.7 were much higher those when N/P ratio was under 15.7. Under condition of low nitrate concentration, the dependence of Skeletonema costatum growth on nitrate was increased. The release of DOC was promoted obviously by enrichment of nutrient.
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发布时间：2023-07-07 - 摘要：The growth condition of Skeletonema costatum was studied in different phosphorus concentration by the adding-nutrients experimental method and by batch culture experiments were conducted. PH, DOC, nutrients concentration of the culture medium and the N/P ratio of the cell were measured periodically. The results showed that the phosphorous concentration determined the growth rate of Skeletonema costatum and the maximum cell density. PH of the culture medium began to decreased drastically as soon as the exponential growth period was over. It seems to be a herald to the Skeletonema costatum growth condition. The DOC concentration increased faster in the culture medium with higher cell density as the result of the addition of more phosphate, and could still keep increasing trend for a while after the exponential growth period of Skeletonema costatum ended. The N: P ratio in the Skeletonema costarum cell was about 15:1. which was close to the Redfield ratio. From the N:P ratio in the cell, we could deduce that when the Skeletonema costatum enters a new environment, it first concentrates phosphorous, and then uses it later, the initial absorption rate of phosphorous was faster than that of nitrogen.
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发布时间：2023-07-07 - 摘要：This paper reports four species including a new species, Avrainvillea xishaensis Tseng, Dong et Lu sp. nov, are recorded for the first time from China.关键词：Avrainvillea;new species;new record
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发布时间：2023-07-07 - 摘要：Twenty-one sea urchins were recorded in this paper, eleven of them are recorded for the first time in China. All the sample were collected from the continental shelf area of the East China Sea by the Institute of Oceanology, Chinese Academy of Sciences from 1958 to 1982. The twenty-one species of the sea urchins belong to 7 orders, 11 families and 17 genera. The following is the name list, those with an asterisk are the species recorded for the first time in China.
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发布时间：2023-07-07
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