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1.
Microstructure profiling measurements taken on a shallow Black Sea shelf and in Lake Banyoles and Boadella reservoir (Both in Spain) are analyzed to investigate the influence of boundary-layer-induced turbulence of various sources on mixing in the water interior. The state of turbulence in shallow waters is examined and details of microstructure data processing and error analysis are discussed. The dependence between averaged activity parameter AG and buoyancy Reynolds number Reb for the shelf turbulence indicates that for Reb < 1 the state of turbulence can be described by the fossil turbulence model, which postulates AG-Reb1/2. For Reb> 1, however, the influence of Reb on AG is weak, signifying that the buoyancy Reynolds number can no longer serve as the governing parameter for active turbulent mixing. The generation of turbulence by a one-minute long wind bursts (the Boadella reservoir) increases the averaged dissipation rate (e) of the surface mixed layer by more than 5 times (up to 3×10-6 W kg-1). The influence of the wind bursts was also traced below the ther-mocline, where turbulent patches with 相似文献
2.
This paper proposes a new method for determining the intrinsic acidity constantsK
a1
int
andK
aj
int
. The new method is a great improvement over the modified Langmuir plot method generally adopted in that determination of
these constants is not dependent on the specific surface area
of the marine solid particles. The new method was used to determineK
a1
int
,K
2a
int
and
for the main inorganic components of marine solid particles, including illite, montmorillonite, kaolinite, goethite, γ-AlOOH.
amorphous ferric oxide, δ-MnO2, manganite, SiO2 and calcium carbonate, and can facilitate the study on the effect of solution constituents, solution temperature, ionic strength,
etc. on the value of
. 相似文献
3.
Kang Xinglun 《中国海洋湖沼学报》1990,8(4):348-353
To make surface seawater flow, the shear stress of the wind blowing on the sea must overcome the work of cohesion of seawaterW
c. Oil film on the sea will drift along the wind direction so long as the shear stress of the wind overcomes the work of adhesion
between the water and the oilW
a or the work of cohesion of oil Wt,o.
Experiments bear out the theory that surface tension of seawater is more than twice that of oils generally, so that the wind
influenced drift velocity of the oil film is over two times that of the wind-driven surface current. The wind factor for surface
current in Jiaozhou Bay is 0.025, while those for the drift velocities of O-diesel oil film and the used light crude oil film
are 0.070 and 0.052 respectively.
Generally the primary factors influencing the movement velocity of oil film on the sea are current, wind, and the physicochemical
properties of the oil. The drift velocity of oil film is determined from analysis of the work of adhesion between seawater
and oil. Experiments and actual observations agree with the theoretical analysis.
Contribution No. 1831 from the Institute of Oceanology, Academia Sinica 相似文献
4.
A preliminary theoretical and experimental study was conducted on internal wave modes and their weak nonlinear resonant interaction
in a nonlinearly stratified fluid. An asymptotical solution of the modes and a dispersion relation of internal waves in a
stratified fluid with density profile
similar to that in our experiment were obtained theoretically. The resonant-interaction mechanism to 2nd order approximation
is also discussed. The resonant interaction of the 3rd and 4th mode internal waves excited by the unstable 1st mode wave is
analyzed on the basis of data obtained by conductivity probes. The resonant-interaction condition, i.e.,
,k
1+k
3+k
4=0, is examined. It is shown that the resonant instability increases with pycnocline thickness and wave maker driving frequency.
This work is supported by the National Natural Science Foundation of China. 相似文献
5.
In this paper, the linear continuously stratified ntxiel of the abyssal circulation proposed by Pedlosky (1992) was emended to include the second order term - (γθm) in the vertical turbulent mixing pararneterization of - (ω‘θ‘）x = kvθxx- θxxx, in which kv is a vertical diffusion coefficient,and γ is the second order coefficient of turbulent mixing (or simply called γ-term and γ＜0 is only allcmed). The influence of the γ-tema on the baroclinic structure of the abyssal circulation driven by up-welling out of the abyss was investigated, It was found that the γ-term has a noticeable influence on thebaroclinic structure of the upwelling driven abyssal circulation. For uniform upwelling, it favors the baroelinic layering of the abyssal circulation in the eastern part of the basin, but prevents the layering in thewest. In addition, this parameter was found to decrease the vertically averaging meridional velocity of theabyssal circulation frcrn the west to the east on the southern boundary. For upwelling localized near theeastern boundary, the γ - term favors baroclinic layering of the abyssal circulation in the whole basin.Especially, on the southern boundary the γ - term could strengthen the vertically averaging meridional ve-loeity in the west, but gready weaken it in the east. The ntntel presented here might be considered as anextension of the Pedlosky baroclinic ntntel of the abyssal circulation. 相似文献
6.
A study on the curves of the exchange ratioE(%)- pH on the liquid-solid interface of the systems Zn (II) with clay minerals, (Kaolinite, illite and montmorillonite),
Zn (II) with hydrous ferric oxides (amorphous ferric oxide, geothite and hematite), Zn (II) with hydrous manganese oxide (γ-MnOOH,
manganite and δ-MnO2) etc. in seawater resulted in the discovery of new plateau type exchange ratioE(%)-pH curves not yet reported in literature. The two factors that decide the growth, decline and the change of the “plateau
type” curve are: (1) the inherent characteristics of systems, which can be explained by the exchange constants
(i=1, 2, 3, etc.) of interfacial stepwise ion/coordination particle exchange between liquid and solid; and (2)
. The theory of interfacial stepwise ion/coordination particle exchange in seawater was applied to explain the experimental
results of the above study and a general formula was derived for the plateau type exchange ratioE(%)-pH curves. The theoretically simulated and calculated curves coincided well with the experimental results. This paper
provides new and powerful experimental basis to support the theory of interfacial stepwise ion/coordination particle exchange
in seawater.
The project was supported by the National Natural Science Foundation of China. 相似文献
7.
Four kinds of polysaccharides (FA, FB, FC and FD) were extracted and purified from a red alga Furcellaria lumbricalis. Their monosaccharide composition, average molecular mass
and structural feature were determined by gas chromatography (GC), high performance gel permeation chromatography (HPGPC)
and Fourier transform infrared spectroscopy (FTIR), respectively. The results showed that FA and FB were composed of galactose
(Gal), 3,6-anhydro-galactose (AnG) and 4-sulfated-galactose (G4S), which were structurally similar to β-carrageenan and κ-carrageenan.
FC was composed of sulfated galactose and small amount of AnG, indicating that it was a hybrid-sulfated galactan. FD was composed
of α-1,4-glucose and belonged to floridean starch. The respective yields of FA, FB, FC and FD were 4.84%, 33.74%, 8.76% and
13.5%, and the corresponding
were 537 kD, 432 kD, 513 kD and 51 kD respectively. Owning to its high content (>60%) of polysaccharide, F. lumbricalis will be a good source of marine sulfated polysaccharide and shows its potential utilization in food and medicine. 相似文献
8.
A multilayer study of pCO2 for the Yellow and South China Seas in the surface waters was conducted based on data from four cruises sponsored by the
China SOLAS Project in 2005 and 2006, including data for the surface microlayer (SML), subsurface layer (SSL) and surface
layer (SL). The carbon fluxes across the air-sea interface were calculated. The results showed that the pCO2 values in the surface waters of the study area decreased in the following order: pCO2 SML > pCO2 SSL > pCO2 SL. The highest values were found in March for all SML, SSL and SL, followed by those in April, and the lowest were in May.
The pCO2 values had a significant positive correlation with temperature or salinity. While there was no relationship between pCO2 and longitude, there was a significant negative correlation between it and latitude, i.e., ‘high latitude low pCO2’. By using four calculation models, the carbon dioxide fluxes (
) in spring in the Yellow and South China Seas, which were found to act as a ‘sink’ of atmospheric CO2, were preliminarily estimated on the basis of the pCO2 data in the SML to be −7.00×106t C and −22.35×106t C, respectively. It is suggested that the
calculated on the basis of pCO2 data in the SML is more reliable than that calculated on the basis of those in the SL. 相似文献
9.
Sea bottom stress is conventionally assumed to be directly proportional to the square of the verticallyaveraged velocity,and the drag coefficient to be dependent on the speed and direction of the wind on the sea surface,the depth and dimension of the sea,the period of the tide and so on. In this paper a three-dimensional numerical model is used to discuss the relation the dragcoefficient and the above-mentioned factors.It can be shown from calculation that the relation, is valid,that the drag coefficient is a constant in a major part of a sea as thought conventionally,andthat there is a small area near the coast where the drag coefficient is far greater.We call it singular area. A number of conclusions on the relation between the drag coefficient and the speed and direction ofthe wind,the sea depth and so on,were obtained. 相似文献
10.
Incubation experiments are carried out to study the exchange rates of dissolved inorganic nutrients including silicate, phosphate, ammonium, nitrite, and nitrate （^vSiO3-Si,^vPO4-P, ^vNH4-N, ^vNO2-N and ^vNO3-N） at the sediment-water interface in the Jiaozhou Bay. Major factors influencing the exchange rates are discussed in detail, which include the dissolved inorganic nutrient concentrations in porewater （Cpw）, water and clay contents, and grain size of the sediments （CH2O, Cclay and GSsed）. The results may provide insight into the dynamics of nutrient transport and the environmental capacity of nutrients in Jiaozhou Bay, and should be beneficial to solving the problems caused by excessive nutrient input this area. 相似文献
11.
Results of a series of experiments (on the adsorption of divalent metal ions by dried alginic acid, Na and Ca alginates of
different composition and block structure) conducted in this systematic study of the effects of the composition and structure
of alginates on the static adsorption equilibrium of divalent metal ions indicate that the properties of alginate adsorption
to divalent metal ions are highly different, depending not only on the cations used, but also on the form and structure of
the alginates. There is close correlation between the adsorption properties and the structure of the alginates. The selectivity
coefficient of Na alginate for Cd-Sr ion exchange tends to increase with the increase of theM/G ratio in alginate, whereas the adsorption capacity of Ca alginate for Cu2+ ion decrease with the increase of the G-block or the average length of the G-block
and the total adsorption capacity of alginic acid is found to vary in the same order as theF
MM(diad frequency) in alginate in the mixed solution of Sr2+, Ba2+ and Cd2+.
Contribution No. 2166 from the Institute of Oceanology, Chinese Academy of Sciences. 相似文献
12.
We collected leiognathid fishes from the Hainan Island and Beibu Gulf between November 2007 and December 2008. Ten of these
specimens were identified as Nuchequula blochii (Valenciennes 1835), which is the first record of this species in China’s waters. These specimens are distinguished by the
combination of these characteristics: breast fully scaled, cheek naked, anteroventral profile of the lower jaw almost straight,
a conspicuous dark blotch distally on the anterior part of spinous portion of dorsal fin, a yellow blotch distally on posterior
part of spinous portion of dorsal fin, and a dark blotch on nape. This paper reviews the genus Nuchequula and describes three species that occur in China’s waters. 相似文献
13.
On the deep sea demersal fish communities of the East China Sea 总被引：1，自引：0，他引：1
Cluster analysis of data on the species similarity index offish samples taken at various sampling stations of different depths by the R /V " Dongfang " of the East China Sea Fisheries Research Institute, Chinese Academy of Fisheries Science, during the deep sea demersal fish resources survey in May - November, 1981, showed deep sea demersal fish fauna of the western part of the East China Sea can be grouped into the following communities :1)The outer continental shelf community ,2)The continental slope community, and3)The western Okinawa Trough community .The authors found that not only the species diversity index, but also the species similarity index are important criteria to reflect the structure of biotic community. 相似文献
14.
LIPeiliang LILei ZUOJuncheng ZHAOWei CHENZongyong 《中国海洋大学学报(英文版)》2004,3(1):10-16
1 Introduction Itisverycommontousetidalconstantsinoceanen gineering .Ingeneral,tidalconstantscanbeobtainedfromtidalharmonicanalysisbasedonthehourlydata .However ,thereisamassofhistoricaltidaldatamere lyonthetimeandmagnitudesofsuccessivehighandlowwaterlevels .Moreover ,sometimeswemayhavetidaltableswhichonly givethepredictedvaluesofhighandlowwatersforsomeports,withoutinforma tionontidalconstants .Inthesetablesthetimeinter valsbetweensuccessivetidalextremaareirregular .Therefore ,mostofthestan… 相似文献
15.
Rapid, high-throughput and reliable methods are urgently required to accurately detect and monitor harmful algae, which are responsible for algal blooms, such as red and green tides. In this study, we successfully developed a multiplex PCR-based DNA microarray method capable of detecting nine harmful algal species simultaneously, namely Alexandrium tamarense, Gyrodinium instriatum, Heterosigma akashiwo, Karenia mikimotoi, Prorocentrum donghaiense, Prorocentrum minimum, Ulva compressa, Ulva ohnoi and Ulva prolifera. This method achieved a limit of detection (LOD) of 0.5 ng of genomic DNA (orders of magnitude of the deci-nanogram range) in the tested algae cultures. Altogether, 230 field samples from ship ballast waters and seaport waters were used to evaluate the DNA microarray. The clinical sensitivity and specificity of the DNA microarray assay in detecting field samples were 96.4% and 90.9%, respectively, relative to conventional morphological methods. This indicated that this high-throughput, automatic, and specific method is well suited for the detection of algae in water samples. 相似文献
16.
Previously, we had characterized several structurally interesting brominated phenols from the marine red alga Symphyocladia latiuscula collected from various sites. However, Phytochemical investigations on this species collected from the Weihai coastline of Shandong Province remains blank. Therefore, we characterized the chemical constituents of individuals of this species collected from the region. Eight bromophenols were isolated and identified. Using detailed spectroscopic techniques and comparisons with published data, these compounds were identified as 2,3-dibromo-4,5-dihydroxybenzyl methyl ether (1), 3,5-dibromo-4-hydroxybenzoic acid (2), 2,3,6-tribromo-4,5-dihydroxymethylbenzene (3), 2,3,6-tribromo-4,5-dihydroxybenzaldehyde (4), 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether (5), bis(2,3,6-tribromo-4,5-dihydroxyphenyl)methane (6), 1,2-bis(2,3,6-tribromo-4,5-dihydroxyphenyl)-ethane (7), and 1-(2,3,6-tribromo-4,5-dihydroxybenzyl)-pyrrolidin-2-one (8). Among these compounds, 1 and 2 were isolated for the first time from S. latiuscula. Each compound was evaluated on the ability to inhibit protein tyrosine phosphatase 1B (PTP1B), which is a potential therapeutic target in the treatment of type 2 diabetes. Bromophenols 5, 6, and 7 showed strong activities with IC50 values of 3.9, 4.3, and 3.5 μmol/L, respectively. This study provides further evidence that bromophenols are predominant among the chemical constituents of Symphyocladia, and that some of these compounds may be candidates for the development of anti-diabetes drugs. 相似文献
17.
Measurement of the surface emissivity of turbid waters 总被引：2，自引：0，他引：2
For interpreting thermal IR imagery of the ocean surface, the emissivity of the sea surface is usually assumed to be constant,
approximately 0.98. However, the emissivity varies with the roughness of the sea surface, and the concentration and type of
suspended particulates. The emissivity variations caused by the suspended sediments introduce significant errors in the satellite-derived
temperature maps of turbid coastal waters.
We measured in the laboratory the thermal IR emissivity of water as the suspended sediment concentration was varied from zero
to extremely high values. The results indicated that increasing the sediment concentration decreases the spectral emissivity
within the 8–14 μm waveband.
Editor’s note A conference on West Pacific Circulation Influence in China Seas (WEPACICS) was held during November 10–14, 1986 in Qingdao,
China, under the joint auspices of the Institute of Onceanology, Academic Sinica (IOAS) and the National Science Foundation,
United States, and under the convernorship of Ya Hsueh, Florida State University, and Hu, Dunxin, IOAS. The primary subject
of the conference is the influence of the West Pacific Circulation in the Yellow Sea and the East China Sea through the intermediary
of the Kuroshio. In the conference more than 20 papers were presented, summarizing the works on the interaction between the
Yellow and East China Sea, and the oceanic circulation, and the research experiences gained in the studies of the Gulf Stream
and its influences in the U.S. Coastal waters were shared. In order to facilitate scientific exchange we chose to published
successively the significant papers presented at the conference in the journal. 相似文献
18.
The Changjiang River estuary and adjacent waters are one of the most notable regions for red tides/harmful algal blooms in China's coastal waters.In this study,phytoplankton samples were collected and analyzed during the outbreak stage of red tides in May 2009.It was found that dinoflagellates,Prorocentrum donghaiense and Karenia mikimotoi,and diatoms,Skeletonema spp.and Paralia sulcata,were the major taxa dominating the phytoplankton community.Cluster analysis,non-metric multidimensional scaling(NMDS) and analysis of similarities(ANOSIM) was conducted on a data matrix including taxa composition and cell abundance of the phytoplankton samples.The analyses categorized the samples into three groups at a similarity level of 30%.Group Ⅰ was characterized by estuarine diatoms and distributed mainly in the highly turbid estuarine region.Group Ⅱ,which was dominated by the diatom Skeletonema spp.and represented the red tide of Skeletonema spp.,was situated around Group Ⅰ in the sea area west of 122°50'E.Group Ⅲ was characterized by a high proportion of dinoflagellates and was found further offshore compared with Groups Ⅰ and Ⅱ.Group Ⅲ was further divided into two subgroups(Ⅲ-S1 and Ⅲ-S2) at a similarity level of 40%.Group Ⅲ-S1 was characterized by the presence of the benthic diatom P.sulcata,representing phytoplankton samples collected either from the bottom or from the sea area affected by upwelling.GroupⅢ-S2 was dominated by dinoflagellates and represented red tides formed by P.donghaiense and K.mikimotoi.A gradual change of red-tide causative species was observed from the estuary to the offshore sea area,from diatoms to armored dinoflagellates and then unarmored dinoflagellates.Environmental factors associated with each group,and thus affecting the distribution of phytoplankton and red tides,are discussed. 相似文献
19.
Periphytic biofilms in aquaculture waters are thought to improve water quality, provide an additional food source, and improve the survival and growth of some reared animals. In the Asia- Pacific region, particularly in China, artificial reefs are commonly used in the commercial farming of sea cucumbers. However, few studies have examined the epilithic biofilms on the artificial reefs. To gain a better understanding of the succession of epilithic biofilms and their ecological processes in sea cucumber culture waters, two experiments were conducted in culture waters of the sea cucumber Apostichopus japonicus in Rongcheng, China, using artificial test panels. On the test panels of succession experiment, more than 67 species were identified in the biofilms. On the test panels of seasonal variation experiment, more than 46 species were recorded in the biofilms. In both experiments, communities of epilithic biofilms were dominated by diatoms, green algae and the annelid Spirorbis sp. In the initial colonization, the dominant diatoms were Cocconeis sp., Amphora spp. and Nitzschia closterium in June, which were succeeded by species of Navicula, Cocconeis and Nitzschia (July to September), and then by Licmophora abbreviata, Nitzschia closterium and Synedra spp. in the following months. A diatom bloom in the autumn and filamentous green algae burst in the summer were also observed. Ecological indices well annotated the succession and seasonal changes in epilithic communities. Multidimensional scaling (MDS) analysis found significant differences in diatom community composition among months and seasons. Fast growth of biofilms was observed in the summer and autumn, whereas the biomass of summer biofilms was largely made up of filamentous green algae. Present results show that the components of epilithic biofilms are mostly optimal foods of A. japonicus, suggesting that biofilms on artificial reefs may contribute important nutritional sources for sea cucumbers during their growth seasons. Future works should include quantitative determination of the contribution of epilithic biofilms to the diet of A. japonicus, potential roles of epilithic biofilms in regulating the water quality of sea cucumber ponds, and the regulation of epilithic biofilms in sea cucumber culture ponds. 相似文献
20.
Oplegnathus fasciatus (rock bream) is a commercial rocky reef fish species in East Asia that has been considered for aquaculture. We estimated the population genetic diversity and population structure of the species along the coastal waters of China using fluorescent-amplified fragment length polymorphisms technology. Using 53 individuals from three populations and four pairs of selective primers, we amplified 1 264 bands, 98.73% of which were polymorphic. The Zhoushan population showed the highest Nei’s genetic diversity and Shannon genetic diversity. The results of analysis of molecular variance (AMOVA) showed that 59.55% of genetic variation existed among populations and 40.45% occurred within populations, which indicated that a significant population genetic structure existed in the species. The pairwise fixation index F st ranged from 0.20 to 0.63 and were significant after sequential Bonferroni correction. The topology of an unweighted pair group method with arithmetic mean tree showed two significant genealogical branches corresponding to the sampling locations of North and South China. The AMOVA and STRUCTURE analyses suggested that the O. fasciatus populations examined should comprise two stocks. 相似文献