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151.
围垦的社会经济价值及其对海洋环境影响的评估   总被引:2,自引:0,他引:2  
从围垦滩涂与保护湿地的关系着手,针对浙江省的滩涂围垦现状,讨论了沿海滩涂实施围垦工程所创造的社会经济价值,分析了湿地生态的环境特征及其对自然界的贡献,指出并探讨了海岸带资源开发与海岸工程建设所带来的问题,从湿地保护和经济可持续发展的角度提出了相关的建议。  相似文献   
152.
Starting from the widespread phenomena of porous bottoms in the near shore region, considering fully the diversity of bottom topography and wave number variation, and including the effect of evanescent modes, a general linear wave theory for water waves propagating over uneven porous bottoms in the near shore region is established by use of Green‘s scond identity. This theory can be reduced to a number of the most typical mild-slope equations curreutly in use and provide a reliable research basis for follow-up development of nonlinear water wave theory involving porous bottoms.  相似文献   
153.
Profiles observed by Sea-Wing underwater gliders are widely applied in scientific research. However, the quality control(QC) of these data has received little attention. The mismatch between the temperature probe and conductivity cell response times generates erroneous salinities, especially across a strong thermocline. A sensor drift may occur owing to biofouling and biocide leakage into the conductivity cell when a glider has operated for several months. It is therefore critical to design a mature real-time QC procedure and develop a toolbox for the QC of Sea-Wing glider data. On the basis of temperature and salinity profiles observed by several Sea-Wing gliders each installed with a Sea-Bird Glider Payload CTD sensor, a real-time QC method including a thermal lag correction, Argo-equivalent real-time QC tests, and a simple post-processing procedure is proposed. The method can also be adopted for Petrel gliders.  相似文献   
154.
长江口海水比重的直接测定   总被引:1,自引:0,他引:1  
海水的比重是海水的一个重要物理性质,也是研究海水运动所必需的一个参数。关于大洋海水比重及其与氯度、盐度和电导的关系已有许多报导[3,5-9],为了制定新的国际海洋学常用表,Cox等人对世界各海洋表层海水的比重、盐度和温度的关系又进行了重新研究[3]。他们指出,除去低盐海水以外,所得结果与Knudsen水文表数据吻合较好,但Knudsen水文表的比重数据平均偏低0.006σt。  相似文献   
155.
The expansion of the temperature anomaly field in the North Atlantic is considered using natural orthogonal functions of depth. It is shown that the first few components of this expansion describe the field both at the surface and in the upper 1000 m layer accurately enough. The relation between the water temperature anomaly at some levels and the above components is estimated for various regions of the ocean.Translated by Mikhail M. Trufanov.  相似文献   
156.
Observations and Estimations of Directional Spectrum of Sea Waves   总被引:1,自引:1,他引:1  
The directional spectrum is one of the basic characteristics of sea waves. The observations of directional spectrum of sea waves were successfully conducted at platform Bohai 8 during 1991 and 1992 using a wave gage array for the first time in China. Based on the field data, the directional spectrum which depends on the wave growth is given in this paper. Before observations, the effects of the type of gage array, the distance between the gages and the platform itself on the measured results and the precision of some methods for estimating the directional spectrum were investigated and compared with the methods of numerical simulations and model tests of multi-direcitonal irregular waves. This ensures the quality of the observations and estimations of the directional spectrum.  相似文献   
157.
贻贝(Mytilus edulis L.)是一种冷水性双壳类软体动物,它在我国沿岸分布的南限是胶州湾,但仅见于港内码头及船底上,且数量不多。 1958年青岛市水产局、原青岛市海水养殖场和中国科学院海洋研究所等单位曾一起自大连和烟台移贻贝苗至青岛试养,次年养殖架上也曾有少量幼苗附着,但未能大量繁殖起来。1971年后胶南县海水养殖试验场及青岛市第二海水养殖场等先后进行数十亩乃至数百亩移苗养殖,附苗量虽有所增长,但直至1974年仍缺乏生产意义。这种情况引起我们的思考:胶州湾贻贝苗源能否大量发展?它的限制因素是什么? 1972年至1973年,我们与烟台地区海水养殖试验场等单位曾对烟台沿岸贻贝苗源进行调查研究,确认当时烟台苗种产量不高的主要原因是附着基不足,其次是亲贝不足,据此试验成功了“废旧草绠采苗法”。之后,随着采苗器材的增加及养殖面积的不断扩大,烟台芝罘湾已发展成为一个较好的苗场,通常可供万亩以上生产用苗。这个经验对我们开发胶州湾的苗源很有启发。 1975年胶南县在胶州湾大力推广“废旧草绠采苗法”,收割海带后保留废旧海带架两万台采贻贝苗, 1976年进一步扩大贻贝养殖面积,继续留绠采苗。我们在青岛市水产局及胶南县水产局等单位的协助下,于1975年9月及1976年8-9月,对胶州湾内及湾口(青岛前海)留绠采苗的情况进行了调查,这些调查资料即为本文的主要依据。  相似文献   
158.
阐述把维生素B12生产菌添加到培养水中培养褶皱臂尾轮虫BrachionusPlicatilis的买验。共18株细菌分离于轮虫培养池,其中,有一株产维生素B12的假单胞杆菌TP4对轮虫的生长繁殖有明显的促进作用。把TP4菌株培养后,加入到2L的烧杯和500L的水槽中培养泰国S型轮虫时.在9d(天)和6d(天)中,轮虫密度从124~139和242~288个体/ml增殖到4,417~5,540和1,017~1,254个体/ml,分别比对照组增加了4~6及2~3倍。  相似文献   
159.
This paper considers the results of numerical experiments involving POLYMODE data assimilation by a barotropic model for synoptic ocean dynamics. The model's response the data assimilation for various space-time discretenesses of assimilation is studied. Results derived from the application of optimal interpolation algorithms and modified optimal filtration algorithms are compared. Qualitative similarity to the calculations carried out through the simulation modelling technique is noted. Optimal assimilation algorithms are determined, depending on the space-time discreteness used. An optimal sampling discreteness for the POLYMODE conditions is suggested.Translated by Vladimir A. Puchkin.  相似文献   
160.
A statistical ensemble of microphysical parameters of the background stratospheric aerosol at altitudes of 15 to 30 km is modeled on the basis of experimental data. The aerosol attenuation coefficients (AACs) in the wavelength range 0.38–16.3 μm are calculated for all realizations of the ensemble by algorithms of the Mie theory. Analysis of correlations between the AACs and the microphysical parameters indicate that the AAC correlates most strongly with the total volume V and area S of all particles. The errors of determining the microphysical parameters from AAC measurements are analyzed via the method of linear regression. It is shown that, if the AAC is measured with an error of 5%, the errors of determining both the particle size distribution (PSD) for particles with sizes of 0.4 to 4 μm and the parameter S are an order of magnitude smaller than the prior uncertainty, whereas the error of determining V is two orders of magnitude smaller than the prior uncertainty. Schemes of AAC measurements with the SAGE III, ISAMS, CLAES, HALOE instruments and an IR interferometer in the visible and IR regions are discussed. It is shown that combining the schemes makes it possible to extend the range of particle sizes for which the PSD is retrieved with a satisfactory accuracy and to increase the accuracy of determining S and V substantially and the accuracy of determining the total number of particles N opt to a lesser extent. Examples of interpreting AAC measurements carried out simultaneously with the SAGE III and HALOE instruments within the same spatial region are presented. A systematic discrepancy between vertical profiles of S and V obtained from SAGE III and HALOE measurements is revealed.  相似文献   
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