共查询到20条相似文献,搜索用时 109 毫秒
1.
Distribution of Pacific-origin water in the region of the Chukchi Plateau in the Arctic Ocean in the summer of 2003 总被引:6,自引:1,他引:6
1Introduction Besidestheprecipitationandriverdischarges,the watersinthePacificOceanandtheAtlanticOceanare thesourcesoftheArcticOceanwater.TheAtlantic waterenterstheArcticOceanviatheFramStraitand theBarentsSea.Foritsdenserfeatureduetohigh salinity,mostofitsinkstothenorthofSvaldbardand circulatesinallthedeepbasinsintheArcticOcean, formingthedeepandbottomwatersoftheArcticO- cean(Aagaardetal.,1985;Rudelsetal.,1999).The BeringStraitistheonlychannelforthePacificwater toflowintotheArcticOce… 相似文献
2.
3.
4.
The materials were obtained from the survey conducted in the Kuroshio area of the East China Sea to the Southwest of Kyushu in Japan (29°30'-32°00', 128°00'-130°'00'E) on board the R. V. Yoko Maru of Seikai Regional Fisheries Lab, Fisheries Agency, Japan in June 15~28, 1988 during China-Japan Joint Research on the Kuroshio. Zoo-plankton was collected by means of the North Pacific Net with model TSK flowmeter through vertical haul from 50 -Om. Temperature and salinity were measured with CTD. 134 species (including 4 spp. ) of planktonic copepods were preliminarily identified in the survey area. Most of them belonged to the tropical and subtropical species and a few of them were the warm-temperate species and eurytopic species. The main dominant species vteieOncaea venusta, Oithona plumifera, Clausocalanus furcatus, C. Arcuicornis, Paracaianus dculeatus, Oithona similis, Temara turbinata, Oncaea media, Undinula danvinii, Acartia negligent, Corycaeus speciosus, Scolecithrix danae, etc. The total number 相似文献
5.
The study was made by observing the annual change of the gonadal development of amphioxus in Xiamen cohtinuously for two years from November, 1986 to November, 1988. We determined the gonadal diameter, gonadosomatic index of each amphioxus, and observed the histological characteristic of the gonadal development of the female and male by cut section, which provided the basis for dividing the stages gonads and the determining level of the gonadal development of amphioxus in each month. 相似文献
6.
Preliminary study of the retention mechanism of planktonic copepods in the Jiulong Estuary in China 总被引:1,自引:0,他引:1
The horizontal and vertical distribution patterns of five planktonic copepods,Calanus sinicus, Acartia pacifica, Tortanus derjugini, Acartiella sinensis and Pseudodiaptomus poplesia, predominant in the Jiulong Estuary, were investigated from May 2003 to April 2004. The results showed that the distribution of these copepods was related to the tidal period but that each species had its own specific pattern. C. sinicus showed no tidal vertical migration behavior and was thought to be a non-resident species in this estuary. Among Acartia pacifica,T. derjugini,Acartiella sinensis, more individuals occurred in the surface than in the bottom waters during flood tide, and the pattern was reversed during ebb tide. The epibenthic copepod P. poplesia usually remained in the bottom waters in the upstream part of the estuary, but it displayed strong tidally-oriented vertical migration in the middle reaches of the estuary.Taking into account the hydrographic characteristics of the Jiulong Estuary,it was hypothesized that the planktonic copepods in this estuary had more or less adopted the mechanism of vertically migrating to the surface waters during flood tide in order to make use of the inflowing tide, and then sinking to the bottom during ebb tide to avoid being carried out of the estuary by net outflow. 相似文献
7.
A. I. Ryabinin Yu. A. Mal’chenko L. V. Saltykova E. A. Danilova S. A. Bobrova 《Physical Oceanography》2011,21(2):115-128
We study the space-and-time variability of the concentrations of 27 microelements (Sc, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Mo,
Ag, Cd, Sn, Se, Sb, Ba, La, Ce, Sm, Eu, Tb, Hf, Hg, Pb, Au, Th, and U) and Sr in the sea, river, and waste waters of the South
Coast of Crimea in 2002–2007. Parallel with the data about elements studied earlier, we present, for the first time, the data
of investigations of the contents of rareearth elements (Lu, Nd and Yb) whose concentrations in the major part of the analyzed
samples of seawater were lower than the limit of their quantitative determination. We present the ranges of the concentrations
of elements and perform their comparison with the data of the previous period of monitoring. 相似文献
8.
The Pelotas Basin is the classical example of a volcanic passive margin displaying large wedges of seaward-dipping reflectors (SDR). The SDR fill entirely its rifts throughout the basin, characterizing the abundant syn-rift magmatism (133–113 Ma). The Paraná–Etendeka Large Igneous Province (LIP), adjacent to west, constituted the pre-rift magmatism (134–132 Ma). The interpretation of ultra-deep seismic lines showed a very different geology from the adjacent Santos, Campos and Espírito Santo Basins, which constitute examples of magma-poor passive margins. Besides displaying rifts totally filled by volcanic rocks, diverse continental crustal domains were defined in the Pelotas Basin, such as an outer domain, probably constituted by highly stretched and permeated continental igneous crust, and a highly reflective lower crust probably reflecting underplating.The analysis of rifting in this portion of the South Atlantic is based on seismic interpretation and on the distribution of regional linear magnetic anomalies. The lateral accretion of SDR to the east towards the future site of the breakup and the temporal relationship between their rift and sag geometries allows the reconstitution of the evolution of rifting in the basin. Breakup propagated from south to north in three stages (130–127.5; 127.5–125; 125–113 Ma) physically separated by oceanic fracture zones (FZ). The width of the stretched, thinned and heavily intruded continental crust also showed a three-stage increase in the same direction and at the same FZ. Consequently, the Continental-Oceanic Boundary (COB) shows three marked shifts, from west to east, from south to north, resulting into rift to margin segmentation. Rifting also propagated from west to east, in the direction of the final breakup, in each of the three segments defined. The importance of the Paraná–Etendeka LIP upon the overall history of rupturing and breakup of Western Gondwanaland seems to have been restricted in time and in space only to the Pelotas Basin. 相似文献
9.
Cynoscion guatucupa Cuvier 1829 is a migratory pelagic fish species, which has a wide geographical distribution. It is the most important fishing resource for local communities in Bahía Blanca estuary and has been captured by artisanal fishermen since the 1900s. The industrial fleet has been fishing this species in the coastal area of Buenos Aires province since the 1950s, and, since 1970, landings have increased sharply. Between 2000 and 2004, the artisanal fishery in the estuarine waters of Bahía Blanca collapsed. Variations in total landings of the artisanal fleet might have arisen from the environmental variables within the estuary, fishing activity in the surrounding sea region, local pressure within the estuary and/or several other variables. Our results suggest that neither oceanographic parameters nor local pressure seem to have influenced the artisanal fishery of C. guatucupa in the estuarine region. Instead, this fishery seems to have been partially influenced by the increasing fishing pressure exerted by the industrial fishing fleet operating in open waters around the estuary. This study emphasizes the need to take into account fisheries data from both the estuarine environment and the surrounding sea region, particularly when designing management plans for the sustainable use of migrating fish resources. 相似文献
10.
S. G. Demyshev 《Physical Oceanography》2010,20(3):184-195
Within the framework of the Mellor–Yamada approach, we realize a numerical scheme for the calculation of the coefficients
of turbulent viscosity and diffusion in the z -system of coordinates for the three-dimensional model of operative prediction of currents in the Black Sea. Some discrete
analogs of the equations for turbulent kinetic energy and turbulence macroscale are studied. Their high sensitivity to the
choice of finite-difference approximations is demonstrated. On the basis of the comparison of the results of prognostic experiments
with the data of observations, we choose the best approximation of the term used to describe the generation pf turbulence
energy. 相似文献
11.
S. I. Kondrat’ev 《Physical Oceanography》2010,20(2):136-148
We discuss the influence of hydrophysical and biological-chemical processes on the distribution of dissolved oxygen in waters
of the Sevastopol bay in various seasons. In the winter period, against the background of low rates of biological-chemical
processes, the hydrophysical processes provide the homogeneous distributions of temperature and oxygen. In summer, the hydrophysical
processes remain dominant, but the influence of biological-chemical processes becomes noticeable. In the autumn period, the
vertical distribution of oxygen is strongly affected by biological-chemical processes. 相似文献
12.
ApplicationofthefourmodelsofdirectionalspectraintheBohaiSea¥WuXiujieandTengXuechun(FirstInstituteofOceanography,StateOceanicA... 相似文献
13.
Theapplicationofthefractalgeometryinthestudyofsea-floorvolcanoTaoChunhui,JinXianglong,LuWenzhengandHuaZugen(ReceivedOctober4,... 相似文献
14.
In this paper, numerical modelling of the fluctuation of the thermocline in the Bohai Sea has been made using a two-dimensional nonlinear model in stratified ocean and the model for the depth of the thermocline under the effects of wind stirring. The computed results depict the variations of the fluctuation of the thermocline driven by different kinds of wind fields. The fluctuation of the thermocline in the Bohai Sea varies somewhat with different directions, paths and locations of typhoon (cyclone). Under the effects of strong wind, the thermoclines both sink due to mixing and fluctuate. Furthermore, the fluctuation of the thermocline speeds up mixing. At last, the thermoclines disappear after 12-15 h when the strong wind increases from Force 6 to Force 9. 相似文献
15.
ModellingofthebarotropicprocessesintheBohaiSea¥HuangDaji;ChenZongyongandSuJilan(SecondIngtituteofOceanography,StateOceanicAdm... 相似文献
16.
We make an attempt to study specific features of weather- and climate-forming processes developing due to the energy and mass
transfer between the ocean and the atmosphere in the North Atlantic, as well as responses of the climate of Ukraine to the
main climate-forming factors. These studies are based on a statistical model in the form of a system of third-order regression
equations with feedback. We deduce a system of generating functions that allow us to estimate the regression coefficients.
Within the developed model, we applied the factor analysis to compress the input information about the affecting factors in
the region where the weather ships were located. This allowed us to reveal the tendencies of variations in the characteristics
participating in the energy and mass transfer. The response of the climate in various regions of Ukraine to the processes
running in the North Atlantic was determined using the cluster analysis whose algorithm was developed by the authors. We performed
a number of experiments for various situations in the region of the North Atlantic that are possible due to the global warming
of the climate and studied the response of climatic characteristics on the territory of Ukraine under similar processes. The
adequacy of the developed model was verified on the basis of data on the real situation in February 2006. It is shown that
the model satisfactorily describes the responses of climatic characteristics in regions of Ukraine to variations of the affecting
factors in the North Atlantic. 相似文献
17.
R. Yu. Tarakanov 《Oceanology》2014,54(1):1-7
The horizontal structure of the jets of the Antarctic Circumpolar Current (ACC) is analyzed on the basis of CTD- and LADCP- sounding performed during a hydrophysical survey with a 10-mile spatial resolution in the central part of the Drake Passage in October–November of 2008. According to the modern multijet classification of the ACC, the survey area covered the zones of three jets of the South Polar Current (SPC), which is the middle branch of the ACC. The current jets revealed a fine horizontal thermohaline structure, which was manifested even in the case of the confluence of individual jets into a “superjet.” 相似文献
18.
19.
- Abundance of total bacteria, heterotrophic bacteria, coliform and oil degradable bacteria and their relations with salinity and suspended matter in the frontal waters in the Hangzhou Bay are described. The results obtained show that the highest abundances of total bacteria , heterotrophic bacteria are encountered around the front and near the northern shore of the Hangzhou Bay, where a positive correlation ( r =0. 70) between the total bacteria abundance and the total suspended matter (TSM) is persent. Moreover,the abundance of oil degradable bacteria being an indicator of oil pollution, is also high in that region. 相似文献
20.
This introductory paper lays the basis for this supplementary issue by briefly presenting the state of knowledge on the KwaZulu-Natal (KZN) Bight at the start of this multi-disciplinary, multi-institutional, ship-based research project that ran from 2009 to 2013. The rationale and aims of the project are also described. The project was a major component of the South African Department of Science and Technology’s African Coelacanth Ecosystem Programme (ACEP), which has been prominent in supporting research on the east coast of South Africa and the wider South-West Indian Ocean. Pivotal to this was the RS Algoa, which was made available for two 30-day surveys (winter and summer) in the KZN Bight by the Department of Environmental Affairs. Although some aspects of the bight ecology are known, much of the research is dated and fragmented, and required refreshing and consolidation in order to produce a platform upon which the understanding of the region’s ecosystem functioning could be established. Much of the oceanographic knowledge is also dated, with no dedicated surveys and significant measurements undertaken since 1989. The overarching theme of the KZN Bight project was to examine the relative importance of sources of nutrients to the central KZN coast and how these are taken up and recycled in the ecosystem, and to describe aspects of the benthic biodiversity, which is poorly described in much of this region. An ambitious project, its accessibility to a ship-based research platform and the diverse scientific skills of the participating scientists allowed considerable success, as reflected in the papers that follow. 相似文献