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1.
Irene Fischer 《Marine Geodesy》2013,36(1):37-59
The current ambition to achieve a 10‐cm marine geoid focuses attention on the interdisciplinary problem of relating oceanographic to geodetic measurements, and on the apparent conflict between them along the United States’ coasts. The concepts underlying the comparisons in this conflict are analyzed, and shown to leave a possibility of diffusing the deadlock by more precise reformulations. Concepts which have been equated in practical applications under less stringent accuracy requirements need to be refined and related more precisely through interdisciplinary efforts. An example is given of a geodetic utilization of density differences in the ocean, akin to but not the same as the idea of steric leveling, in order to highlight the similarity and dissimilarity between some geodetic and oceanographic ideas. 相似文献
2.
-Study on the effects of microorganism secretive membrane and covering layer of macrofouling organisms-Balanus reticulatus, Ostrea plicatula, Membranipora, Corophium and Algae on the corrosion of carbon steel and low-alloy steel by the determination of natural corrosive potentials, linear polarization and the polarization curver of dynamic potential scanning through an electrochemical equipment.The results show that the microorganism secretion membrane formed on sample surface has some protective role, during the initial period of exposure (about ten days). Then protective role decreases and corrosive rate increases with the lapse of immersion time. The protective role of some macrofouling organisms is shown in order as follows: Corophium> Balanus reticulatus>Algae>Membranipora>Ostrea plicatula. 相似文献
3.
The soluble organic matters were extracted from marine sediments in the sea area of Southern Ocean by using organic solvents. The hydrocarbon and carboxylic acid fractions were separated with the thin layer chromatography. The organic compounds of 170(H), 21α(H)- bishomomoretene, cholest - 5 - ene, 24 - methyl - cholestene, 24 - ethylcholestene, hop-17(21)-ene, neohop - 13(18)-ene, fern-8-ene, fern-7-ene, 170(H), 210 (H) - hop - 22(29)-ene (diplotene), steranes, β, β-hopanes C29 -C31 and unsaturated carboxylic acids C18:2Δ9.12 , C18:1Δ9,C18:1Δ11 , have been identi-fied in the hydrocarbon and carboxylic acid fractions by means of gas chromatography and gas chromatography - mass spec-trometry - data system. The distributions of 3, a - bishomomoretene, β,β- hopene and β,β- hopane are characteristic of immature organic matter. The sterane, C29 20S/20R epimer ratio 0. 6 indicate that the organic matter had experienced a thermal evolution in the early sedimentation. The unsaturated fatty acids espec 相似文献
4.
Investigations on the preparation, structure and biochemical characteristics of tropomyosin (Tm) of Acetes japonicus, A. chinensis and Pseudeuphausia sinica, collected from Xiamen coastal water, show that: (1) Tm could be isolated by salting fractionation in the range of 20-35% ammonium sulphate saturation, and the contents of them are 0.86%, 0.87% and 0.70% of dry weight respectively. (2) Molecular weight of Acetes detected by SDS-PAGE method is 3.3-3.6×104, while that of P. sinica, 3.2-3.5×104. (3) Isoelectric points of all the three Tm determined by isoelectric focusing method are at about pH 5.0. (4) Crystalline spindles of above three Tm can be formed in phosphate buffer containing Mg f at pH 4.8 or pH 7.2, showing cross striations with a repeat period of 38-40 nm under the electron microscope by negative staining, and there are fine lines at irregular intervals in each striation. (5) The characteristics of the chemical composition of three Tm reveal that the strong polar amino acids account for m 相似文献
5.
Diatoms are major primary producers of microbial biomass in the Antarctica. They are found in the water and sea ice. The distribution, abundance of the ice diatoms and their relation to the environmental factors inside and outside the ice have been studied for its special role in the Antarctic Ocean ecology. In this paper we describe the abundance, distribution and composition of diatom assemblages in 相似文献
6.
Karyotypes of three species of the marine Veneroida molluscs 总被引：1，自引：0，他引：1
INTRODUCTIONExceptforcorbiculalivinginfreshwater,themostVeneroidamolluscsliveinthesea .Theyarewidelydistributedwithlargequantityofcategories.Manyofthebivalvemolluscsareculturedfortheireconomicvalue .ThespeciesofSolengrandis,SaxidomuspurpuratusandMactrachinensisareaquaculturedinthenorthernseasofChina .Morphologyandcultivationbiologyofthebivalvemolluschavebeenreported (Qietal.,1 989;Weietal.,1 995;Wangetal .,1 984 ) .Asthefoundationofbivalvemollusccytogenetics ,chromosomestudyiscritical… 相似文献
7.
The Huanghe River estuary, as one of world-known large river estuary and its adjacent sea re-gion are important aquatic product base with rich marine product resources in North China. The au-thors collected about 60 species of fishes. crustacea. mollusca and polychaeta in this region (119°05′-20′E,37°15′-38°15′N) from Apri1 to May. 1984. The concentration of Zn, Cd, Pb and Cu in eachmarine organisms was measured and concentration factors of trace metals were calculated. The ashingmethods was used for sample treatments. The concentration of trace metals was determined by anti-adsorption physical coating mercury electrode inverse polarography (Davis A1660 Differential CathodRay Polarograph). 相似文献
8.
《Marine Policy》2013
European marine policies have recently been consolidated, and the scalar organisation of marine governance has been questioned. This paper examines this phenomenon in Europe as a result of implementation of the European Marine Strategy Framework Directive (MSFD) and examines changes in the role of the national state vis à vis other levels of jurisdiction in marine policy. The relevance of use pressures differs across European member states, as do national policy styles and institutional configurations. Therefore, a nuanced picture is needed regarding the ways European marine policy is being implemented. To this end, the paper employs a co-evolutionary perspective studying the cases of Germany, Spain and Portugal. European marine policy has become anchored in the most relevant policy fields except agriculture and fisheries, and competency regarding its environmental dimension has been strengthened, formalized and clarified as a result of the MSFD. Its implementation, tied to international marine protection, comes following initiatives to develop maritime economies. In Portugal, implementation of the MSFD did not change the scalar organisation of natural resource governance. In Spain and Germany, the MSFD led to disputes regarding clarification of competencies. In the course of implementing the MSFD in Germany, challenges are tied to the political dimensions of formalizing practices and producing integrated policies. In Spain and Portugal, comprehensive stock-taking is itself a challenging task. 相似文献
9.
《Marine Policy》2017
Guatemala's rich coastal and marine biodiversity provides essential ecosystem goods and services to local residents and the national economy through artisanal and commercial fisheries, aquaculture, port exports and, to a lesser extent, tourism. As in many other countries, national policies emphasise the significance of marine conservation and marine resources, primarily through implementing marine protected areas (MPAs). However, this assumes that governance, as reflected in legal, institutional and organizational frameworks, political capacity and human resources is sufficiently developed to ensure MPAs meet these goals. These issues are explored through presenting the first detailed analysis of coastal and marine governance in Guatemala. The research highlights a range of barriers to good governance which restrict the extent to which MPAs can function effectively. Recommendations are made which can capitalise upon the potential for locally managed marine areas as a means to facilitate the improved governance of coastal and marine resources in Guatemala. 相似文献
10.
Screening of protease-producing marine yeasts for production of the bioactive peptides 总被引：1，自引：0，他引：1
Over 400 yeast strains from seawater and sediments were obtained, but only five strains named HN2 -3, N13d, N13C, Mb5 and HN3 - 2 among them could form clear zones around their colonies on the double plates with 2.0% casein. Peptides in the hydrolysate produced by the proteases from strains HN2 -3 and N13d had higher angiotensin I-converting-enzyme （ACE）-inhibitory activity. The two marine yeast strains were identified to be Aureobasidium pullulans according to the results of routine yeast identification and molecular methods. After purification of the proteases from the two marine yeast strains, it was found that the optimal pH for them was both 9.0, both of them were serine alkaline protease. However, the optimal temperature for the protease from the strain HN2 -3 was 52℃ while that from strain N13d was 48℃. ACE-inhibitory activity of the peptides in the hydrolysate of shrimp protein produced by the purified protease from the strain HN2 -3 was the highest while antioxidant activity in the hydrolysate of spirulina protein produced by the purified protease from the strain N13d was the highest. 相似文献
11.
Quaternary marine ostracoda on the west coast of the Bohai Sea 总被引：1，自引：0，他引：1
According to the results of analysis of the marine ostracoda biofacies from over 160 drilled holes on the west coast of the Bohai Sea, i.e. Hebei and Shandong Provinces, Tianjin, and the east part of Beijing, the present paper is a discussion of their palaeoecological and stratigraphigical significance. The investigation of ostracoda thanatocoenoces in the modern coastal zone suggests that the distribution of marine ostracoda has been controlled by the salinity and depth of water. The study of Quaternary marine ostracoda should be concentrated mainly on the determination of their biofacies and palaeogeographigical conditions, so as to provide evidence for the determination of transgression range, palaeoshoreline and sca-leve! changes. 相似文献
12.
The existing methods of downward continuation of potential field cannot be used to continue the aeromagnetic data to the marine surface because of the limited continuation distance. An iteration method for the downward continuation of potential field with a much larger continuation distance has been developed, which can continue the aeromagnetic data to the marine surface and get the marine - magnetic chart with the same scale as the aeromagnetic data. This downward continuation method will greatly raise the ef- ficiency of marine - magnetic investigation. The principle of the iteration method is presented. The method is demonstrated on synthetic models and real aeromagnetic data. Also, the error brought by continuation is discussed. The efficiency of the iteration method for the downward continuation of potential field is compared with the fast fourier transform （FFT） method, the former is much better than the latter. 相似文献
13.
The behaviour of free methionine in the artificial marine habitat and the characteristic of absorption by clam were studied by trace method. The results showed that more than 70% of free methionine was utilized by marine organisms. The percentage of concentration methionine in suspended matter, Platymonas, sediment and clam was 11.4%, 24%, 7.8% and 34% respectively. The main path of absorption was viscera, seconded by mantle and gill. It was transferred to muscle after 24 h. The direct absorption of methionine from sea water by clam was more important and faster than that from food. 相似文献
14.
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15.
Effects of surface waves and sea spray on air–sea fluxes during the passage of Typhoon Hagupit 总被引：3，自引：1，他引：2
Air–sea exchange plays a vital role in the development and maintenance of tropical cyclones(TCs). Although studies have suggested the dependence of air–sea fluxes on surface waves and sea spray, how these processes modify those fluxes under TC conditions have not been sufficiently investigated based on in-situ observations.Using continuous meteorological and surface wave data from a moored buoy in the northern South China Sea,this study examines the effects of surface waves and sea spray on air–sea fluxes during the passage of Typhoon Hagupit. The mooring was within about 40 km of the center of Hagupit. Surface waves could increase momentum flux to the ocean by about 15%, and sea spray enhanced both sensible and latent heat fluxes to the atmosphere,causing Hagupit to absorb 500 W/m~2 more heat flux from the ocean. These results have powerful implications for understanding TC–ocean interaction and improving TC intensity forecasting. 相似文献
16.
INTRODUTION ln the ocean environrnent prediction nurnerital medels in the China seas, the TaiwanStrait was usually considered as oPen boundary either in the study of the East China Ai or thefouth China As, so it is difficult to get a satisfactory predicted result in this strait area.Recently many stud1es on the Taiwan Strait have been made, arid the predlction serviceproects of the drine prediction stage are increasing and have achieved high--favorable econodricbenefit. Nevertheless, t… 相似文献
17.
In this paper, without recourse to the nonlinear dynamical equations of the waves, the nonlinear random waves are retrieved from the non-Gaussian characteristic of the sea surface elevation distribution. The question of coincidence of the nonlinear wave profile, spectrum and its distributions of maximum (or minimum) values of the sea surface elevation with results derived from some existing nonlinear theories is expounded under the narrow-band spectrum condition. Taking the shoaling sea wave as an example, the nonlinear random wave process and its spectrum in shallow water are retrieved from both the non-Gaussian characteristics of the sea surface elevation distribution in shallow water and the normal sea waves in deep water and compared with the values actually measured. Results show that they can coincide with the actually measured values quite well, thus, this can confirm that the method proposed in this paper is feasible. 相似文献
18.
State‐of‐the‐art technology is presently being used for the acquisition of water level and meteorological data in the Intra‐Americas Sea to support the Global Sea Level Observing System (GLOSS) network of sea‐level monitoring stations. GLOSS stations provide data for the investigation of regional relative sea level change in areas of complex tectonic motion, national geodetic vertical datums, near real‐time data for input to climatic diagnostic numerical models, calibration of satellite altimeter and scatterometer data, and the evaluation of the feasibility of producing synoptic mean sea level charts for the prediction of climatic trends, long‐range weather forecasts, and ocean processes. 相似文献
19.
Charles McCann 《新西兰海洋与淡水研究杂志》2013,47(4):619-640
20.
-low-frequency sea level fluctuations in the Hangzhou Bay in winter and summer, 1973-1974 are analyzed in this paper. The established multi-spectrum response models effectively identify the different dynamical factors and their contributions to the low-frequency sea level fluctuations inside the bay. The results show that the Ekman transport due to longshore winds is the major mechanism to induce the sea level fluctuations, more important than the frictional effect of local winds. There also exists obviously the influental effect of the free fluctuations of the continental shelf. In addition ,a simple estimation suggests that the remarkable sea level fluctuation of 0. 4 d-1 in the bay is related to the resonance of the Huanghai Sea and the Bohai Sea (taken as a single bay). 相似文献