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大型藻酶解单细胞用于贝类育苗的研究 总被引：2，自引：0，他引：2
用海藻工具酶将紫菜和裙带菜解离成单细胞作为饵料对海湾扇贝亲贝和幼体、魁蚶亲贝和皱纹盘鲍稚鲍进行了研究。结果表明：(1)海湾扇贝亲贝全喂紫菜细胞其效果与喂全微藻的效果相近，亲贝都能成熟，排放精卵和正常胚胎发育。微藻与紫菜细胞混合投喂可加速性腺发育，性腺指数较高。全喂紫菜细胞能够满足幼体的生长发育和变态。但变态率、生长率较全喂微藻和混合投喂的低。(2)紫菜细胞和微藻分别或混合投喂魁蚶亲贝，都能满足亲贝的性腺发育，进行正常受精、孵化和变为D形幼体。(3)用裙带菜细胞投喂稚鲍与人工配合饵料比较，能显著提高稚鲍的存活率。研究表明。由大型藻生产单细胞饵料，在海产动物育苗中具有广阔的应用前景。 相似文献
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海水育苗室的优化设计与综合利用 总被引：1，自引：0，他引：1
我国沿海数以百计的各类海水育苗室为我国海带、对虾、扇贝等大宗水产品的养殖生产提供了充足的优质苗种,有力地推动了我国水产养殖业大规模的迅速发展。但是,近些年来,在海水育苗室的设计和建设方面也存在着不少问题,有待研究和解决。同时,原有育苗室单打一式的生产,妨碍了育苗室的利用率和经济效益的提高。本文分别以对虾和海带育苗室作为深池类和浅池类的代表,论述了优化设计组合的一些主要经验和设计方法;提出了育苗室建设的主要原则与技术要求;探讨了原有育苗室的改造与综合利用的途径。 相似文献
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山东省有许多对虾育苗室建于半咸水河(沟)畔。正常年份,育苗时节正逢江河枯水期,涨潮时海水沿河道上行,使河(沟)水盐度迅速上升并达到25以上,正好为育苗所用。近年来,由于抗旱和防讯的需要,对虾育苗期间大河上游提闸泄水,致使作为其支流的河(沟)枯水期不枯,水的盐度上不来,育苗生产无法进行。在此情形下 相似文献
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１９９３年，于文登市小观海珍品育苗养殖场，在海湾扇贝和对虾育苗结束后，利用其配套的单胞藻培养地进行真鲷育苗，利用对虾育苗池和卤虫孵化池培养轮虫。在不增加任何设备的前提下，育成全长３．０１～６．５０ｃｍ，平均全长３．４４ｃｍ的真鲷商品鱼种１６１１１６尾，从仔鱼培育到商品苗种的成活率达到２４．７２％，平均单位水体出苗量达到２６８５尾，１９９３年７月１９日通过了文登市科委组织的验收。正材料和方法１．１育苗设施亲鱼产卵池（１个）和鱼苗培育池（６个）皆用单胞藻培养池（规格为３．８ｍ×３．７ｍ×０．８ｍ，水… 相似文献
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墨西哥湾扇贝东海海域人工育苗规模化试验 总被引：11，自引：0，他引：11
墨西哥湾扇贝 (Ａｒｇｏｐｅｃｔｅｎｉｒｒａｄｉａｎｓｃｏｎｃｅｎｔｒｉｃｕｓ)因其耐低温能力较差 ,在我国北方沿海推广养殖不甚理想 ,但很适合我国东海海域养殖。然而苗种供应极其有限 ,限制了养殖生产的进一步发展。为此 ,１９９６年农业部下达了“北方种群的墨西哥湾扇贝引进”、１９９９年浙江省科委下达了“墨西哥湾扇贝人工育苗和养殖产业化研究”课题 ,经两年的试验取得了较好的结果。现将２０００年春季人工育苗试验报告如下。１材料与方法１ .１亲贝来源及促熟２０００年３月２３日张福绥从青岛沿海挑选墨西哥湾扇贝亲贝１０… 相似文献
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斑节对虾育苗中“红圈病”的防治 总被引：3，自引：0，他引：3
在对虾育苗期间，育苗池底或池壁上经常出现桃红色的斑点，形成为大小不一的红色的圆圈。红圈蔓延迅速，有时在１，２ｄ之内，便暴发和占满着整个池底和池壁。这种现象，俗称“红圈病”。凡是发生红圈的育苗池中，对虾幼体活力下降，厌食，趋光性差，并陆续出现死亡。严重时，虾苗几乎全部死亡。红圈病病原为真菌［１］。该病原菌多发生在光线暗弱的室内育苗池中。目前，有关防治红圈病的报道很少见。１９９３年４月期间，笔者在进行斑节对虾种苗生产时，对防治红圈病分别用不同药物进行试验。１试验材料与方法１．１在斑节对虾生产育苗池中… 相似文献
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对光合细菌在斑节对虾育苗中的应用效果进行了研究。结果表明，光合细菌能有效地促进对虾幼体生长发育，提高出苗率，并可改善育苗水质，起到预防病害的作用。 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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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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The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
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Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献
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The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included. 相似文献