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九龙江口磷的界面分配和转移 总被引：5，自引：0，他引：5
１９９２年８月航次调查结果表明，九龙江口水体中磷的迁移呈保守行为，ＴＰ和ＰＰ含量随着海水盐度的降低呈增加趋势，ＤＰ含量刚好相反；Ｓ〈１５的低盐区，盐度对磷迁移的影响比较显著。 相似文献
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对海南岛南岸古珊瑚后报海温研究的几点看法 总被引：1，自引：0，他引：1
海南岛南是研究古珊瑚后报古海温的理想场所之一。根据近海现今海温与珊瑚生长率季节变化的特点，指出开展古珊瑚地化指标后报海面温度（ＳＳＴ）研究时，应尽可能采用先进取样技术进行小样品取样，应开展珊瑚生长模式研究，注意ＳＳＴ变化中数年平均值与气候平均值的差值范围，建议重视近数在年冬季ＳＳＴ后报工作。 相似文献
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河口及近岸海区营养盐含量较丰富,是海洋生物繁殖的良好环境,因此调查研究这些区域水体中的营养盐有重要的现实意义。AsTon指出,近年来河口区磷酸盐、硅酸盐、硝酸盐及其它无机形式氮行为的研究已引起了许多研究人员的注意。一方面是由于这些物质对生物过程包括对控制生产力的过程具有重要作用;另一方面是由于对排入河口富营养污水(例如生活污水等)影响的关注。 关于河口及近岸区营养盐含量变化及行为的研究情况曾进行了大量的研究工作。当河水与海水混合时,河流带入营养盐的行为,如活性磷酸盐、活性硅酸盐及硝酸盐是否有转移,保守性如何,是近年来较为关心的问题之一,也是一个十分复杂的过程。且影响 相似文献
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本研究采用学习记忆行为训练和生化测定的方法,观察了我国４种常见海蛇的乙醇浸出物（ＡｌｃｏｈｏｌｉｃＥｘｔｒａｃｔｓｏｆＢｏｄｉｅｓｏｆＳｅａ Ｓｎａｋｅ．ＡＥＢＳＳ）对小鼠的正常学习记忆、东莨菪碱（Ｓｃｏｐｏｌａｍｉｎｅ,Ｓｃｏｐ）所致记忆障碍、脑不同部位蛋白质含量的影响。结果表明,ＡＥＢＳＳ（剂量５００ｍｇ浸出蛋白／ｋｇ体重以上）对正常小鼠的学习记忆能力及脑内蛋白质合成有明显的促进作用;ＡＥＢＳＳ还能极显著地改善Ｓｃｏｐ所致的学习记忆障碍,使Ｓｃｏｐ组大脑皮层和小脑的蛋白质含量显著增加,海马脑区的蛋白质含量增加极显著。结果提示,ＡＥＢＳＳ对小鼠学习记忆的作用机制可能与中枢胆碱能递质系统的蛋白质合成有关。 相似文献
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海蛇乙醇浸出物对小鼠学习记忆的影响 总被引：2，自引：0，他引：2
本研究采用学习记忆行为训练和生化测定的方法,观察了我国４种常见海蛇的乙醇浸出物（ＡＥＢＳＳ）对小鼠的正常学习记忆、东莨菪碱（Ｓｃｏｐ）所致记忆障碍、脑不同部位蛋白质含量的影响。结果表明,ＡＥＢＳＳ（剂量５．００ｍｇ浸出蛋白／ｋｇ体重以上）对正常小鼠的学习记忆能力及脑内蛋白质合成有明显的促进作用;ＡＥＢＳＳ还能极显著地改善Ｓｃｏｐ所致的学习记忆障碍,使Ｓｃｏｐ组大脑皮层和小脑的蛋白质含量显著增加,海 相似文献
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１２５Ｍａ后陆－陆碰撞造成的碳储存的讨论ＤｅｒｒｉｌｌＫｅｒｒｉｃｋ等评论：Ｓｅｌｖｅｒｓｔｏｎｅ和Ｇｕｔｚｌｅｒ（１９９３）认为，在特提斯陆－陆碰撞期间，碳从大气转移到深成变质储集层可能导致了１２５Ｍａ后的全球变冷。但是，由于大气ＣＯ＿２含量长期由... 相似文献
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粉煤灰海上倾倒中几种因素对Se^4＋溶出的影响 总被引：1，自引：0，他引：1
探讨了粉煤灰中的Ｓｅ＾４＋在海水中的溶出现象，找出了几种因素对Ｓｅ＾４＋从煤灰中溶出浓度的影响规律。结论是如果粉煤灰中硒的溶出率在１０％－２０％之间，将粉煤灰投入一个封闭海域，只要固液比达到１：１０００，海水中的硒含量就可达到２－３μｇ／Ｌ，即远远超过海水中硒含量的本底值０．０３μｇ／Ｌ。ＰＨ＝７时，盐度越高，温度越高越有利于粉煤灰中Ｓｅ＾４＋的溶出，从而使硒在封闭海域溶出值远高于海水硒含量的本底 相似文献
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Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance. 相似文献
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Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
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海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。 相似文献
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Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm. 相似文献
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Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
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The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
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