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111.
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
112.
Paraconchoeciadiacanthusn.sp.,anewspeciesofplanktonicOstracoda¥ChenRuixiangandLinJinghong(ReceivedApril16,19931acceptedJuly20... 相似文献
113.
Ocean current forecasting is still in explorative stage of study. In the study, we face some problems that have not been met before. The solving of these problems has become fundamental premise for realizing the ocean current forecasting. In the present paper are discussed in depth the physical essence for such basic problems as the predictability of ocean current, the predictable currents, the dynamical basis for studying respectively the tidal current and circulation, the necessity of boundary model, the models on regions with different scales and their link. The foundations and plans to solve the problems are demonstrated. Finally a set of operational numerical forecasting system for ocean current is proposed. 相似文献
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甲壳动物化学感觉研究进展 总被引:6,自引:0,他引:6
本文从甲壳动物化学受体的形态、动物个体的行为反应以及化学感觉神经元的电生理三方面综述了甲壳动物化学感觉研究近20年的进展。水生动物,如甲壳动物特别是底栖甲壳动物,主要依赖化学感受器获得其生存环境的信息,从而表现出摄食、逃避捕食者、觅偶、交配、洄游等各种不同的行为反应。早期的研究主要是直观的行为观察和化学感受器的形态描述,内容偏重于动物的摄食习性和化学感受器的结构及其分布。随后电生理方法和电镜技术的引入,使化学感觉生理学的研究深入到细胞水平,发现了受体细胞的一些特性,如低自发放电频率、低阈值、调制、适应和去适应、范围分级等。另外,还提出了甲壳动物化学受体对化学信号的两种基本编码方式,即单线编码模式和交叉神经元模式。 相似文献
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118.
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
119.
珠江口现代沉积速率及其反映的沉积特征 总被引:2,自引:0,他引:2
文章分析了珠江河口海区泥沙来源及淤积动态,采用以历史海图分析对比为主,~(210)Pb测年数据校核等方法,参考有关沉积速率定性方面的标志,推算出珠江口不同地段的现代沉积速率,并相应划分出高速率沉积、快速率沉积、中速率沉积和慢速率沉积或稍有侵蚀等4个分区.进而,还论述了沉积作用的特征. 相似文献
120.
A one-dimentional three-layer model for the thermal structure in the Huanghai Sea is presented in this study, me model consists of the upper mixed layer caused by heating and wind mixing, the lower mixed layer driven by tidal mixing, and the thermocline with certain thickness. The entrainment velocities of the upper and lower layers are obtained respectively. The results show that the model is capable of describing the development and decline processes of the seasonal thermocline in the Huanghai Sea, simulating successfully the Huanghai Sea Cold Water Mass, the nearshore front and surface cold water off North Jiangsu and explaining reasonably their formation mechanisms as well as the strong thermocline off Qingdao. It is suggested that the tidal mixing plays key role in the formation of the nearshore front off North Jiangsu and the strong thermocline off Qingdao. The wind mixing and the tidal mixing make the lower layer water with high nutrients go up to the upper layer. This physical process may be sig 相似文献