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21.
I\rnooUcrIoxThe drpdric fish species cor-npositlon is an imPOrtant element 1n the study of fish ecologyand plays an important guiding role ln fishery preduction and roouLrces rnanagement. Lin(l988) and Zhang (1994 and l995) have studied the simi1drities of mpulation COtwsition ofame s1ngle species of different yea-rs including hairtail Trichuras haumee and yellDw cndertwinena cmi. But no rePOrt is available on the discridrination of the sidrildrities amongmuLlt1ple sPecies composition of… 相似文献
22.
Modest observations and numerical experiments were conducted to investigate circulation and brackish water dispersal in a
coastal lagoon southwest of Taiwan. The Chi-Ku Lagoon, partially shielded from the sea by a string of sandbar barriers with
two entrances among them, receives modest and episodic runoff from Chi-Ku Stream. Flood and ebb tidal streams entering and
leaving the two entrances are found to converge and diverge in a flow stagnation area inside the lagoon. Under weak wind conditions,
brackish water is preferentially retained in the flow stagnation area. Besides the observations, scenario runs using a three-dimensional
numerical model also indicate strong modulation by monsoon winds. Both summer southwest monsoon and winter northeast monsoon
reduce brackish water retention; the latter is found to be more effective.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
23.
As a fundamental study to evaluate the contribution of the Kuroshio to primary production in the East China Sea (ECS), we
investigated the seasonal pattern of the intrusion from the Kuroshio onto the continental shelf of the ECS and the behavior
of the intruded Kuroshio water, using the RIAM Ocean Model (RIAMOM). The total intruded volume transport across the 200m isobath
line was evaluated as 2.74 Sv in winter and 2.47 Sv in summer, while the intruded transport below 80m was estimated to be
1.32 Sv in winter and 1.64 Sv in summer. Passive tracer experiments revealed that the main intrusion from the Kuroshio to
the shelf area of the ECS, shallower than 80m, takes place through the lower layer northeast of Taiwan in summer, with a volume
transport of 0.19 Sv. Comparative studies show several components affecting the intrusion of the Kuroshio across the 200 m
isobath line. The Kuroshio water intruded less onto the shelf compared with a case without consideration of tide-induced bottom
friction, especially northeast of Taiwan. The variations of the transport from the Taiwan Strait and the east of Taiwan have
considerable effects on the intrusion of the Kuroshio onto the shelf. 相似文献
24.
中国台湾地区地处欧亚板块与菲律宾海板块之间,地震活动频繁.本文报道了 我国台湾地区及其邻近海域1985~2002年间5.5级以上地震的条带内外频度比分 布,并着重研究了1999—2002年中发生的3次7.5级以上地震前的条带现象.其结 果表明:台湾地区近期发生的3次7.5级以上大地震前,5.5级以上地震呈条带分 布.这些条带符合条带内地震个数Nin≥6的条件,符合条带内、外频度比Nin/(Nin Nout)≥75%的条件,也符合条带长宽比大于5的要求,只是与板内地震条带相比,条 带的长度较短. 相似文献
25.
采用RT-PCR技术和RACE技术成功克隆淡水鱼类斑鳢sGST基因cDNA全序列,推测得到氨基酸序列,初步分析其结构功能域及系统进化关系。结果表明,斑鳢sGST基因cDNA序列全长为898bp,编码225个氨基酸。斑鳢sGST与真鲷、金头鲷、鲽、黑头鲦、川鲽、大口黑鲈等最新定名为ρ型的sGST氨基酸同源性较高,ρ型sGST为水生生物所特有并共同占据进化树上独立的分枝;与大鼠、小鼠、人等哺乳动物sGST现有所有类型同源性均很低,并且在进化树上距离也较远,表明本研究成功克隆的sGST基因应属于ρ型,可能在鱼类等水生生物对水栖环境的适应上有重要作用。 相似文献
26.
台湾海峡金色小沙丁鱼幼鱼索饵群体研究 总被引:2,自引:1,他引:2
本文研究了台湾海峡南部和北部的金色小沙丁鱼当年生幼鱼计数性状和量度性状特征差异,并结合其生物学特性、产卵场、洄游及海区环境特征进行综合分析。结果表明,台湾海峡南部和北部的索饵幼鱼仍属于同一地方种群:闽南-台湾浅滩语地方种群。根据其索饵洄游特点,可分为台湾海峡南部和北部两个索饵群体. 相似文献
27.
Geological Characteristics and Distribution of Submarine Physiographic Features in the Taiwan Region
Ho-Shing Yu 《Marine Georesources & Geotechnology》2003,21(3):139-153
The sea floor topography around Taiwan is characterized by the asymmetry of its shallow and flat shelves to the west and markedly deep troughs and basins to the south and east. Tectonics and sedimentation are major controls in forming the submarine physiographic features around Taiwan. Three Pliocene-Quaternary shelves are distributed north and west of Taiwan: East China Sea Shelf (passive margin shelf), the Taiwan Strait Shelf (foreland shelf), and Kaoping Shelf (island shelf) from north to south parallel to the strike of Taiwan orogen. Off northeastern Taiwan major morpho/tectonic features associated with plate subduction include E-W trending Ryukyu Trench, Yaeyama accretionary wedge, forearc basins, the Ryukyu Arcs, and the backarc basin of southern Okinawa Trough. Off eastern Taiwan lies the deep Huatung Basin on the Philippine Sea plate with a relatively flat floor, although several large submarine canyons are eroding and crossing the basin floor. Off southeastern Taiwan, the forearc region of the Luzon Arc has been deformed into five alternating N-S trending ridges and troughs during initial arc-continent collision. Among them, the submarine Hengchun Ridge is the seaward continuation of the Hengchun peninsula in southern Taiwan. Off southwestern Taiwan, the broad Kaoping Slope is the major submarine topographic feature with several noticeable submarine canyons. The Penghu Canyon separates this slope from the South China Sea Slope to the west and merges southwards into the Manila Trench in the northern South China Sea. Although most of sea floors of the Taiwan Strait are shallower than 60 m in water depth, there are three noticeable bathymetric lows and two highs in the Taiwan Strait. There exists a close relationship between hydrography and topography in the Taiwan Strait. The circulation of currents in the Taiwan Strait is strongly influenced by seasonal monsoon and semidiurnal tides. The Penghu Channel-Yunchang Ridge can be considered a modern tidal depositional system. The Taiwan Strait shelf has two phases of development. The early phase of the rift margin has developed during Paleoocene-Miocene and it has evolved to the foreland basin in Pliocene-Quaternary time. The present shelf morphology results mainly from combined effects of foreland subsidence and modern sedimentation overprinting that of the Late Pleistocene glaciation about 15,000 years ago. 相似文献
28.
Circulations east of Taiwan and in East China Sea and east of Ryukyu Islands during early summer 1985YuanYaochu;Cho-tengLiu;P... 相似文献
29.
1 INTsoDUcrIONTemperature is one of the most impoFtant essential factors of ocean, and its verticalstructure, especially the phenomenon ofthermocline, is concerned by military and manufacturepractices at all times. There are two classes of research methods for thermocIine, statisticmethod and numerical method. In recent years, more attention has been paid to the latterwhich becomes the primary development direction. Since Munk et al (1948) pot forward1-D model of thermocline at steady sta… 相似文献
30.