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1.
所谓全人工繁育就是用人工繁育养成至性成熟的子一代（F1）文昌鱼种作为亲体，人工繁育获得子二代（F2）文昌鱼苗以用于人工增养殖。通俗地说，实现文昌鱼全人工繁育批量生产，必须连续突破三道技术难关：（1）用野生亲体人工繁育获得成批量的子一代（F1）文昌鱼苗；（2）在人工条件下将成批量的子一代文昌鱼苗养殖至性成熟以从中选择人工亲体；（3）用人工亲体人工繁育获得成批量的子二代（F2）文昌鱼苗。 相似文献
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利用人工培育的亲鱼所获得的受精卵 ,孵化出仔鱼 30 0万尾 ,在水温 18～ 2 0℃、微充气的培育条件下 ,使用海水小球藻、轮虫、卤虫无节幼体和不同规格的微颗粒配合饲料进行饲喂 ,经 58d培育出平均全长 2 .3cm的苗种 132万尾 ,育苗成活率高达 64.1% ,单位水体最高出苗量达 1.33万尾 / m3;另外 ,还有 1.3～ 1.9cm的苗种 68万尾 相似文献
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东山岛近岸水域厦门文昌鱼浮游幼体的分布 总被引：5，自引：2，他引：5
通过1990年5、8、11月和1991年1月的调查发现，东山岛近岸的厦门文昌鱼（Branchiostomabelcheri）浮游幼体，主要分布在该岛的东部和南部水域。其数量相当多，基本上集中出现在春末（5月）和夏季（8月），平均密度分别为24．4尾／m3（或402．73尾／m2）和232．2尾／m3（2．394×103尾／m2），最大密度（8月下旬）达888尾／m3（1．332×104尾／m2）。体长组成表明，该水域的厦门文昌鱼为分批产卵繁殖。幼体生长发育到体长5mm左右时，身体的形态结构与成体基本相同，并开始陆续转为潜沙生活。 相似文献
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中国科学院海洋研究所细胞研究组承担的国家自然科学基金资助项目“文昌鱼生物学及人工养殖”中的“青岛文昌鱼幼体培育”课题,于1991年1月23日通过该所组织的技术鉴定。与会专家听取了培育技术报告,参观了实验室,抽样测量了文昌鱼幼体的体长。鉴定会一致认为: 相似文献
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日本无针乌贼全人工养殖条件下生活史研究 总被引：4，自引：0，他引：4
自2004—2007年间对日本无针乌贼Sepiella japonica进行了室内全人工养殖。亲体经暂养、促熟、交配后,在投放的附着基上产卵。孵化水温20~26℃,盐度25.0~32.0。受精卵经17~26d破膜而出。刚孵化的幼体为浮游型,胴长约为4mm。开口饵料为动物性活饵,如枝角类、桡足类、强化卤虫。经90~120d培育达到性成熟。获得性成熟个体2万只,成活率可达60%,平均体重100g。最小性成熟个体胴体长50mm。日龄120d可产卵,产卵量300~500粒。 相似文献
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大泷六线鱼全人工繁育技术研究 总被引：7，自引：0，他引：7
2012年~2014年,作者在山东省海洋生物研究院鳌山卫中试基地进行了大泷六线鱼(Hexagrammos otakii)全人工繁育研究,通过人工促熟、激素诱导,培育F1代全人工亲鱼558尾(雄鱼231尾,雌鱼327尾),获得受精卵33.0万粒,孵化F2代仔鱼30.0万尾,受精率98%,孵化率91%。在水温16~17℃、盐度31、p H 7.8~8.1、溶解氧6 mg/L条件下,历时110 d,培育平均全长6.2 cm F2代苗种11.7万尾,苗种成活率39%。作者在国内外首次开展了大泷六线鱼全人工繁育技术研究,丰富了大泷六线鱼养殖基础资料,为大泷六线鱼产业的发展奠定基础。 相似文献
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厦门文昌鱼遗传多样性研究 总被引：6，自引：1，他引：6
运用分子标记技术，对厦门现有文昌鱼(Branchiostoma balcheri Gray)海域(蟹口海域、南线海域、黄厝海域)文昌鱼种群进行遗传多样性研究。通过10个有效引物的RAPD反应，共扩增出238条带，其中多态性条带为121，占总扩增条带的50．84％。Nei指数法分析和UP(小俄统计分析表明：厦门3个海域文昌鱼可分为2个组。平均遗传距离为0．11。南线海域文昌鱼和黄厝海域文昌鱼的遗传距离为0．07，亲缘关系较近，聚类于同一组；蟹口海域文昌鱼与南线海域文昌鱼和黄厝海域文昌鱼的遗传距离分别为0．12和0．14，亲缘关系较远，单独为一组，结论 与3个海域的文昌鱼形态比较结果一致，出现遗传分化。Shannon遗传多样性指数统计结果表明：蟹口海域种群为0．616，南线海域种群为0．497，黄厝海域种群为0．391。厦门文昌鱼种群遗传多样性是各种群的遗传特性与该海域各种环境生态因子长期作用的结果，三元线性相关分析发现目前主要生态因素是底质和海水深度，3个海域中以蟹口海域的自然环境最为优越(其底质为中粗沙或粗中沙、水深8—15m)。根据以上研究结果，本文提出了厦门海域文昌鱼资源的保护建议。 相似文献
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盐度对文蛤孵化及幼体存活和生长的影响 总被引：14，自引：0，他引：14
国内外学者就盐度对文蛤幼体生长发育的影响有过一些报道,但仅局限于浮游幼虫期,而对受精卵孵化和稚贝期进行全面系统的试验研究,目前尚未见报道。本文分别以人工获得的文蛤受精卵、人工培育的浮游幼体和变态稚贝为试验材料,探索盐度对文蛤不同发育阶段生存、生长的影响规律,为人工育苗及稚贝中间育成提供参考。１ 材料和方法１．１ 材料亲贝取自辽宁省盘锦市盘山县双台子河口中潮区砂岗,为３～４龄蛤。经阴干和流水刺激排放精卵,取适量受精卵为孵化期试验材料,其余受精卵在２５℃水温下经人工孵化、选育后,在４０ｍ~３水泥池… 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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Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations. 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