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901.
The present study is based on the materials collected from the middle waters of the South China Sea between 12°-15°N and 111°-118°E during May to July in 1978.The biomass of the phytoplankton (Y, dependent variable) is established to give the biomass of each Species and the environmental factors (i. e. water temperature, salinity, oxygen, silicate and phosphate contents), X1,X2...,X139tt are independent variables that are used to stepwisc regression analysis. Accordicg to the mathematical tests and the practical experience by which a lot of species are deleted and added to the equation, the authors consider that the 4th equation as shown below is optimal one for the model of the biomass on the phytoplankton from this waters.The optimal equation refers to text. 相似文献
902.
The adsorption kinetics of Pb, Cu and Cd on hydrous ferrk oxide (HFO) has been approached in tthe simulated environmental conditions of the Changjiang Estuary. The forward adsorption rate constants of different systems under different temperatures have been determined, and the activation energies of the adsorption for Pb and Cu evaluated (Pb=7 kcal/mol, Cu= 11 kcal/mol). The results show that Pb and Cu are strongly adsorbed by HFO; the order of their adsorption rate is found to be Pb≥Cu≥Cd, which follows thte order of their theonody-namic equilibrium constants. It has been demonstrated that the surface exchange-adsorption is the determining step of the solid-liquid interface process. The field investigation results are theoretically explained by the kinetic mechanism. 相似文献
903.
On the basis of observational data of the eastern part of the West Pacific Ocean, a diagnostic calculation of equatorial flow for this region is performed by using the authors' model equations and computing scheme and methods. For the first cruise (January 3-March 4, 1979), the results show: (i) The primary driving force of the equatorial surface flows comes from the prevailing northeasterly wind field, with an average uniform wind speed Vw = 6.3 m/s. The steady westward wind produces divergent westward flows in the surface layers, causing an upwelling near the equator. The importance of the steady wind stress in the upper layer (120 m) decreases with depth and becomes insignificant at the level of z = 75 m or z = 100 m, (ii) The equatorial undercurrent is a strong eastward and equator-ward flow, with its eastward component of undercurrent larger than its meridional component. The core of the undercurrent is at the thermocline, and its maximum velocity is 88-90 cm/s at the level of z=200 m. The deeper f 相似文献
904.
CHARACTERISTICS ON INTERANNUAL VARIATIONS OF NORTH PACIFIC SST AND ITS RELATION TO EAST ASIA CLIMATE
The interannual variations of the monthly sea surface temperature (SST) in the North Pacific (including Equatorial East Pacific) during 1951-1980 are analysed by means of EOF method. The findings are:(1) In the cold and warm ocean current areas, such as the North Pacific Current, the California Current and the Equatorial East Pacific areas, the convergence speeds are the fastest, while in the Kuroshio and the western part of the North Equatorial Current areas they are fast only in winter.(2) The physical features of the first 3 eigenvectors are obvious. The first eigenvector shows that the SST values are high in the south and low in the north in the latitudinal distribution of the SST field. The warm current area, i.e. the northwestern part of the North Pacific is positive and the cold current area, i.e. the southeastern part of the North Pacific including the Eastern Equatorial Pacific is negative. The zero line of the 2nd eigenvector field runs from northeast to southwest, in the same direction as the 相似文献
905.
本试验是利用对虾(扇贝)育苗池进行室内常温培育裙带菜苗。试验证明,育苗数量完全可以达到生产上的要求,这样既可充分提高对虾(扇贝)育苗池的利用率,又可解决裙带菜苗源不足的问题,促进裙带菜养殖事业的发展。 相似文献
906.
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
907.
本文以1981~1984年4~9月累计18个月在闵中、闵东渔场开展中上层鱼类资源开发性探捕调查的材料,报道了扁舵鲣的生态分布、群体结构和生活史主要特征。鱼群先后于4~7月由南而北进入本渔场,数量分布以5月为多;栖息的最适温、盐度分别为23.5~25.5℃和33~34;渔获群体由0~V龄组成;性成熟的最小年龄为Ⅰ龄,最小叉长271~280mm;生长参数L_∞=484.44mm,W_∞=2050.76g,K=0.5109,t_0=0.3598;瞬时自然死亡率为0.8937,开发比率为0.2138,属于轻度利用的鱼类资源,尚有较大的开发潜力。 相似文献
908.
The impact of several chemical poisons on the Arca granosa absorbing 45Ca was studied. The results showed that the absorption of 45Ca in the blood and the soft tissue by Arca granosa was inhibited by the inorganic compounds of Cu, Zn, Pd, Cd, Hg and so on, among which the inhibition of Cd was the strongest, next was that of Cu and Hg. But the inhibition of the absorption of 45Ca in the shell of Arca granosa was little. The impact of three kinds of energy metabolism inhibitory substances on the absorption of 45Ca by the Area granosa showed that the absorption was an active transfer process. 相似文献
909.
On the basis of the wave energy balance equation, the response model of mean directions of locally wind-generated waves in slowly turning wind fields has been derived. The results show that in a homogeneous field, the time scale of the response is not only related to the rate of wave growth, but also to the directional energy distribution and the angle between the wind direction and the mean wave direction. Furthermore, the law of change in the mean wave direction has been derived. The numerical computations show that the response of wave directions to slowly turning wind directions can be treated as the superposition of the responses of wave directions to a series of sudden small-angle changes of wind directions and the turning rate of the mean wave direction depends on the turning rate and the total turning angles of the wind direction. The response of wave directions is in agreement with the response for a sudden change of wind directions if the change in wind directions is very fast. Based on the no 相似文献
910.
By using the atmosphere-ocean coupled model (CGCM) which is composed of a 2-level global atmospheric general circulation model and a 4-layer Pacific oceanic general circulation model developed in the Institute of Atmospheric Physics of Chinese Academy of Sciences, and two model climatological fields got from the two independent models' numerical integrations respectively, the Pacific sea surface temperature anomalies (SSTA) from 1988 to 1989 are simulated in this paper with observed atmospheric general circulation data and sea surface temperature fields as initial conditions and monthly coupling scheme. In order to remove systematic biases of the model climatological fields, interaction variables between atmosphere and ocean are also corrected simultaneously. The experiments show that the simulation results can be improved effectively if these interaction variables are corrected in spite of the fact that there always exist systematic biases in independent numerical simulations of atmospheric part and oc 相似文献