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51.
Samples of O isotopic tracer were mlleMed at Sections P3,P25,PcM-t/2-E and PCM-1/2.w in both the Fast China Sea and the area to the east of the Ryūkyū-gunto during October-November,1991.Analytical results of the δ18O are as follows: (1) In the Kuroshio area,the δ18O isolines are almost parallel to the 200 m isobath.The value of δ18O is negative and reaches minimum mt the main axis of the Kuroshio,and increases on both sides.(2) In the Taiwan Warm Current (TWC) area there is a high δ18O tongue extending to the northeast.(3) In the area near the coast,the distribution of δ18O isoline shows that the Changjiang River runoff diffuses seaward and the land-ocean isotopic effect from the nearshore to the offshore.(4) The values of δ18O are from -1.0×10-3 to -0.5×10-3 in the shelf.(5) There is a low mre of δ18O value(<-1.6×10-3) at the 600 m layer in the Kuroshio area,which is quite in accord with the existence of a low salinity mre (S G 34.30) between the 600 and 800 m layers in the same area.Finally,the mrrelations of the δ18O with the salinity and temperature,the upwelling and so on are discussed. 相似文献
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北方劳德藻配子和复大孢子的产生 总被引:8,自引:0,他引:8
于1986年10月在厦门近岸采集北方劳德藻,从培养中观察其有性生殖和光对生殖的影响。结果表明,该藻只有宽度为26-40μm的细胞能形成配子和复大孢子;在光照条件下每昼夜只发生1次性化;雌雄配子以不同发育方式形成,配子发生呈现一定的时间程序;强光照和16h光周期最适于性化。由此得知,引起性化既依赖适当的细胞大小,又依赖光诱导的外部因素;产生两种精子数目是与精原孢囊的体积大小紧密相关;性化与光强度之间 相似文献
54.
Paraconchoeciadiacanthusn.sp.,anewspeciesofplanktonicOstracoda¥ChenRuixiangandLinJinghong(ReceivedApril16,19931acceptedJuly20... 相似文献
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The study of the Kuroshio in the East China Sea and the currents east of the Ryukyu Islands 总被引:3,自引:0,他引:3
In this study, the inverse method is used to compute the Kuroshio in the East China Sea and southeast of Kyushu and the currents east of the Ryukyu Islands, on the basis of hydrographic data obtained during September-October, 1987 by R/V Chofu Maru. The results show that: (1)A part of the Taiwan Warm Current has a tendency to converge to the shelf break; (2) the Kuroshio flows across the section C3 (PN) with a reduced current width, and the velocity of the Kuroshio at the section C3 increases and its maximum current speed is about 158 cm/s, and its volume transport here is about 26×106m3/s; (3) the Kuroshio has two current cores at the sections C3 (PN) and B2 (at the Tokara Strait); (4) the currents east of the Ryukyu Islands are found to flow northward over the Ryukyu Trench during September-October, 1987. The velocities of the currents are not strong throughout the depths. At the section C2 east of the Ryukyu Islands, the maximum current speed is at the 699 m levei and its magnitude is 25 cm/s, and i 相似文献
58.
Chemical forms of Ba are determined in samples of suspension and sediment from the Zhujiang Estuary. Their interfacial geochemical processes are discussed. Total suspended Ba content is between 2. 4 and 40. 4 μg/L, and mostly exists in the crystalline form (43. 5%), secondly in the Fe-Mn oxidative form (23.1%). Percentages of organic, carbonate and exchangeable forms are 14. 8%, 11. l%and 7.4%, respectively. Total content of Ba in the sediment is between 158. 6 and 48. 0 ug/g. Percentages of crystalline form, Fe-Mn oxidative form and carbonate form are 78. 4% ,13. 5%and 8. 2%, respectively. Organic and exchangeable forms are not detected. The study on the mechanism of interfacial movement suggests that the salinity range of 10 is the turning point for the varied distribution of Ba. The subsidence of crystalline form affects the decrease of Ba content in suspension. The decrease mostly takes place in the salinity range lower than 10, which corresponds to the high value of Ba content in the sediment. The 相似文献
59.
Cheng-Han Tsai Min-Chih Huang Fu-Ji Young Yin-Chern Lin Hsien-Wen Li 《Ocean Engineering》2005,32(10):4936-1259
Except the commonly selected pressure transfer function derived from the linear wave theory, a previous study on the pressure transfer function for recovering surface wave from underwater pressure transducer suggested that the pressure transfer function is a function of frequency parameter only. With careful analysis, this study showed that the pressure transfer function should include a transducer submergence parameter as that given by the linear theory. It was found that the previously suggested empirical formula should be restricted to measurements with the pressure transducer close to the surface; otherwise overestimation of wave height would result. Field measurements were carried out with an acoustic wave gauge and a synchronized pressure transducer located at various depths with submergence parameter close to 1 (near the sea floor). It was shown that the previous one-parameter empirical formula might overestimate the significant wave height by more than 30%. This study found that with deep-water wave bursts excluded, the transfer function based on the linear wave theory provided a fairly good estimation on the significant wave heights, with an average deviation of 3.6%. 相似文献
60.
2.4拟庸蝶食性的对应分析2.4.1观察量和变量的分组观察量(捕食鱼类)依不同季节(冬、夏季)、不同性别(雌雄性)和不同性成熟状态(幼鱼和成鱼)来分组,因此得到8(23)个观察量。对应分析的变量(饵料)首先根据个体生态的不同分为6个类型:游走多毛类,隐居多毛类,双壳类,不大游动的甲壳类(端足目和等足目),爬行甲壳类(十足国短尾部)和棘皮动物。其他6个类型的饵料生物(类、纽虫类、小型游泳甲壳类、腔肠动物、鱼类及苔藓虫类顺在分组时剔除,其原因为它们的出现可能少了些。考虑到捕食鱼类和饵料双壳类贝壳厚度… 相似文献