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41.
42.
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
43.
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
44.
Variation of reactivity of particulate and sedimentary organic matter along the Zhujiang River Estuary 总被引:3,自引:0,他引:3
To investigate organic matter source and reactivity in the Zhujiang River (Pearl River)Estuary and its adjacent areas, particulate organic carbon (POC), particulate hydrolysable amino acids (PHAA), and Chl a during two cruises in July 1999 and July 2000 were measured. The highest POC and PHAA concentration was observed in the waters with maximum Chl a. The spectra distribution,relative content (dry weight in milligram per gram), PHAA-C% POC and other indicators such as the ratios of amino acids vs. amino sugars (AA/AS) and glucosamine vs. galactosamine (Glum/Gal) suggested that particulate amino acids in the water column and sediments in the Zhujiang River Estuary were mainly derived from biogenic processes rather than transported from terrestrial erosion. In inner estuary where high turbidity was often observable, organic matter was mainly contributed by re-suspension of bottom sediments with revealed zooplankton, microbial reworked characteristics, which suggest that these organic matters were relatively “old“. In the estuarine brackish region, organic matter in water column is mainly contributed by relatively fresh, easily degradable phytoplankton derived organic matter.During physical - biological processes within the eastuary, organic matter derived from phytoplankton was subjected to alteration by zooplankton grazing and bacterial reworking. 相似文献
45.
对广东三水盆地上白垩统三水组、大 山组、古新统莘庄组及始新统 心组、宝月组的系统的古地磁研究结果表明:(1)旋转运动是该区构造运动的主要形式,顺时针旋转盆地拉张发育,这时针旋转盆地挤压衰亡,发育的程度与旋转角度有关;(2)始新世该区旋转方向由顺时针旋转变为道时针旋转,对应于太平洋-库拉板块对欧亚板块作用方向的改变,说明三水盆地的形成发育与太平洋-库拉板块对欧亚板块的作用密切相关;(3)三水盆地所在的华南地块从晚白垩世至始新世在纬向上不存在明显的运动,一直停留在略低于现今纬度的位置上。 相似文献
46.
47.
大沽河是胶州湾最大的入海河流,每年都会给胶州湾带来大量泥沙。本文利用三维的ECOMSED水动力-泥沙数值模型对洪水期的大沽河进行了数值模拟,得到了洪水存在期间以及洪水结束后胶州湾的余流分布、大沽河河道上中下游各层盐度、泥沙浓度随时间变化的趋势以及入海冲淡水和泥沙对胶州湾的影响。 相似文献
48.
49.
In the paper, the sea is divided into two layers with density jumping, assuming that the physical parameters in each layer are independent of depth. Two-layer flow field with tide and wind currents is calculated with extended ADI method, after the calculation for flow field is stable , coupled with temperature diffusion equations and thermohaline depth prediction equation, a four-day time prediction of the surface, bottom temperature and thermohaline depth of the Huanghai and the Bohai Seas. At the same time, three dimensional temperature field of sea water is predicted through vertical temperature distribution function. The result indicates that the prediction quality of the whole model and the fitting degree between the predicted result and the measured values are satisfactory. 相似文献
50.
锶诱导的氧化胁迫对叉鞭金藻(Dicrateria inornata)的影响 总被引:3,自引:2,他引:3
采用不同浓度的锶胁迫方法研究了叉鞭金藻生长、叶绿素、MDA含量及三种抗氧化酶SOD、CAT、GPX活性的变化。结果表明,在实验设计的各种Sr^2 浓度内叉鞭金藻均能生长,但Sr^2 浓度较高时生长受到不同程度的抑制,细胞数量比对照组分别减少15.9%和51.0%;叉鞭金藻中叶绿素含量随着Sr^2 浓度的升高而降低,呈负相关关系;叉鞭金藻中MDA含量在较低Sr^2 浓度下稍呈下降趋势,但与对照组相比并无显著差异,而在23.04mmol/L Sr^2 浓度时是对照的1.25倍;低Sr^2 浓度时,叉鞭金藻中蛋白质含量没有大的变化,当浓度超过5.76mmol/L时则引起蛋白质含量下降;叉鞭金藻中抗氧化酶SOD在低Sr^2 时分别降低12.5%、7.5%和9.5%,高Sr^2 时显著升高,为对照组的85.7%;CAT、GPX活性在低Sr^2 浓度时差别不大,但当浓度为23.04mmol/L时升高显著,比对照组分别增加了19.8%和74.4%。 相似文献