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1.
南美白对虾(Penaeus vannamei)是北美和中南美洲普遍饲养的一种对虾,它不但具有生长迅速、对饲料蛋白质需求量低、出肉率高、离水存活时间长和易集约化养殖等优点,而且具有很强的抗病能力和对环境的适应能力。江苏省大丰市等地区的养殖试验表明,该对虾与中国对虾同池混养,在中国对虾陆续染病死亡的同时,该对虾却健壮活泼、生长旺盛,是值得我国大力推广的对虾养殖新品种。由于南美白对虾自然分布于西太平洋沿岸,我国无天然资源,因此,采取全人工育苗技术解决该虾苗种问题已成为当务之急。研究表明,该种雌虾在日常蓄养条件下性腺不会成熟,在驯养条件下其成熟也无规律(Yono,1990)。迄今为止,国内尚未见有南美白对虾池养雌虾促熟措施方面的报道。为此,我们在1995年工作基础上,于1996年3-5月,对池养南美白对虾雌虾进行了摘除眼柄、强化营养、控制光照等促熟对比试验,取得了较好的效果。 相似文献
2.
于1988年4月和1991年4月分别从厄瓜多尔和美国引进南美洲白对虾仔虾,经驯化、养成和室内人工越冬后,采用单侧眼柄切除手术人工催熟,以试管授精和人工植荚方法进行该种的繁殖技术试验。结果表明,(1)体长在13—16cm的南美洲白对虾雌虾,一般在摘眼后的1—2周内开始性腺发育;产卵量通常为3—10万粒;产卵后的雌虾卵巢可再次发育,最高产卵次数高达19次。(2)应用高频电针法取荚的成功率和取荚后雄虾的存活率均为100％;用上述方法取得的精荚内的精子无需“获能”即可使卵子受精。(3)假裂现象在南美洲白对虾的未受精卵中较为普遍。 相似文献
3.
南美白对虾（Ｐｅｎａｅｕｓ ｖａｎｎａｍｅｉ）是迄今所知世界养殖产量最高的三大虾种之一。具有繁殖季节长，全年可以进行育苗生产；离水存活时间长，可进行活虾销售；对水环境的抗逆能力较强，病害发生率低，养殖管理比较容易；对饵料蛋白质含量的要求较低；生长快，肉质鲜美，加工出肉率高等特点。中国科学院海洋研究所张伟权研究员，自１９８８年从国外将南美白对虾引入我国后，在各级政府主管部门和一些对虾养殖单位的大力支持与配合下，对南美白对虾的繁殖生物学进行了大量、系统的研究：在种苗引进的水环境驯化；雌、雄虾性腺人工… 相似文献
4.
中华绒螯蟹卵巢发育周期的组织学细胞学观察 总被引：28，自引：2，他引：28
于1989－1990年，用组织切片技术，结合外观特征，在光镜水平对浙北地区的中华绒螯蟹卵巢发育周期进行组织学、细胞学观察，并对从卵原细胞增殖到卵母细胞生长、卵子成熟及卵巢退化、重新发生等进行系统观察研究。研究表明，中华绒螯蟹可以观察到第一次成熟分裂中期相为成熟卵的标志，并以此标志将卵子发生分成四期、卵巢发育分成VII期。结果还表明，中华绒螯蟹雌蟹的成熟时间因所处的地理纬度不同而有所差异，浙北地区雌蟹促产怀卵的最佳时间是3月份并延至4月上旬；卵子必须借助海水及交配活动刺激才能达到成熟；因故无法产卵或一直生活在淡水中的成熟雌蟹其整个卵巢即退化，退化卵巢亦能重新发生，新生卵子的形态、发育时序与首次等待青春期蜕壳的蟹一致；孵后母蟹不仅能继续蜕壳生长，其卵巢也能重新发生，新生卵子的形态、发育时序如前一致；但在卵巢结构上彼此又有明显的区别。 相似文献
5.
人工管道诱导大弹涂鱼产卵研究 总被引：12，自引：0，他引：12
报道了人工制作的陶瓷管道诱导大弹涂鱼Boleophthalmus pectinirostris产卵的研究结果，未经激素催熟的亲鱼放入产卵池内7-12d未见产卵，经一次激素注射催熟的亲鱼放入产卵池内第3天开始酱产卵和受精，入池后5d未能产卵雌鱼的卵母细胞开始退化吸收，雌鱼不仅在管道内产卵，而且也将卵产在管道外，池底和池壁，产卵时间集中在下半夜的02：00-04：00，不同产卵池中管道的产卵率差别很大，卵子粘附在管道不同部位的数量和受精率均不相同，强迫配对的亲鱼虽有产卵，但卵子不受精。 相似文献
6.
性外激素诱导大弹涂鱼成熟和产卵 总被引：6，自引：0，他引：6
成熟大弹涂鱼的卵巢、精巢和储精囊稀释液中的性外激素以及缩宫素和脱氧皮质酮（DOC）能诱导第4时相的大弹涂鱼卵母细胞在离体培养的条件下发育成熟，成熟率与性外激素的种类和剂量有关。前列腺素E1（PGE1）单独使用的效果不明显，但与人绒毛膜促性腺激素（HCG）混合使用时显著提高了卵母细胞的成熟率。以卵巢、精巢和储精囊稀释液以及PGE1分别注射雌性大弹涂鱼，剂量为0．01cm^3/尾的卵巢液、0．1cm^3/尾的储精囊液、0．1cm^3／尾的精巢液以及剂量为10μg/尾的PGE1都有诱导卵母细胞成熟的作用，其中储精囊液的作用最为显著。在人工管道中放置大弹涂鱼成熟亲鱼卵巢、精巢或储精囊的稀释液，有诱异性亲鱼进入管道内的作用，其中以储精囊液对雌鱼的吸引作用尤为明显。放置于陶瓷管道或海绵管道内的卵巢、精巢或储精囊稀释液都能诱导大弹涂鱼产卵，在陶瓷管道的产卵量和受精率显著高于海绵管道。 相似文献
7.
石斑鱼是非常名贵的鱼种，有很高的市场价值，吸引了众多国内外养殖业者的关注，在我国南方沿海各省，网箱养殖石斑鱼发展很快，前景十分诱人。然而，因苗种、亲鱼、饵料、病害等诸多问题没能很好解决，阻碍了产业的发展。就现状看，国内已有数家单位实验成功石斑鱼人工繁殖技术，但至今因技术上不稳定、亲鱼难得等原因，仍未能解决商业化大规模石斑鱼全人工培育。 现在好了,有海南大学陈国华、张本等专家组成的课题组经过多年的现场实验、研究，解决了石斑鱼的工厂化全人工培育问题。他们研究和解决的内容包括：（1）亲鱼的选择及培育技术；（2）药物促使石斑鱼提前完成性转化技术；（3）亲鱼催熟、催产技术；（4）石斑鱼的人工孵化技术；（5）石斑鱼苗种培育技术，等等。这全套技术已于2000年4月12日通过了海南省农业厅组织的现场验收。 ●南美白对虾已引进我国多年，育苗、养成技术已基本成型，但其中尚有好多技术性障碍是业者很难逾越的；蓝对虾则是近几年才引进的，有很多技术方面的问题尚未解决。中国科学院九五攻关重大项目专项“池塘对虾持续、高效、健康养殖模式”研究正是解决这些问题的。我们邀请了此项目专家海南大学和中科院海洋所的教授、研究员为业者传授一些技术、技巧，可使听者受益。 ●鲍鱼养殖现在已成了许多业者致富的通衢大道，然而其中很多难以解决的问题阻碍了事业的发展。我们请了专家为您答疑解难。 为使科研成果迅速转化为生产力，推动我国海水鱼养殖业的发展，中国科学院海洋研究所《海洋科学》期刊社会同多位专家决定举办“石斑鱼人工繁殖技术，南美白对虾、蓝对虾等育苗、养成技巧，鲍鱼育苗、养成技术研习班” 现将有关事宜通知如下: @研习内容： 1石斑鱼班 1．1石斑鱼的生物学 1．2埋植外源激素诱导点带石斑鱼性转化 1．3点带石斑鱼亲鱼培育、产卵和孵化 1．4点带石斑鱼人工育苗 1．5点带石斑鱼仔、稚、幼鱼的形态 1．6点带石斑鱼仔鱼开口期的食性 2对虾班 2．1南美白对虾、蓝对虾生物学特性 2.2南美白对虾、蓝对虾育苗、养成技巧 2．3健康养虾与病害防治 3鲍鱼班 3．1鲍鱼的育苗、养成技术 3．2鲍鱼养成期间的病害防治 @开班时间和地点 1时间：2001年2月12日～2月18日， 石斑鱼班：2月12日报到，13～14日开课、研习； 对虾班：2月14日报到，15～16日开课、研习； 鲍鱼班：2月16日报到，17～18日开课、研习。 2地点：海南省海口市人民路58号， 海南大学学术中心 @报名电话及传真：（0532）2879062－2529 E－mail:MSJ@ms.qdio.ac.cn 相似文献
8.
虾池纳潮期日本刺沙蚕幼虫数量及其沉降的研究 总被引：5，自引：1，他引：5
于1992年2月27日－5月30日在文登市高岛盐场养虾场，对日本刺沙蚕（卵、各期胚胎和幼虫）的纳潮数量和幼虫的沉降进行现场调查和实验研究。结果表明，对养虾生产有意义的纳潮期有3个。3月上旬的新月潮，持续12d，数量为（25－50）×103个／m3，主要组成是受精卵、各期胚胎和担轮幼虫。3月甲旬的满月潮持续7d，数量为（2－5）×103个／m3。4月上旬的新月潮持续8d，数量为（2－3．5）×103个／m3。纳潮量与潮汐关系密切，但与平均潮高无显著的相关。各潮期的纳潮数量比应是4：4：2。对16个纳潮虾池测试的平均沉降量为4492个／m2。据现场调查和实验研究，日本刺沙蚕幼虫的沉降期可划为暂时沉降（5－6刚节）和变态沉降（7—10刚节）。出现暂时沉降（4月15日以后），便可执行纳潮后的排水等虾池早期管理。纳潮的定量监测方法简单、快速和准确，可用来指导虾池的纳潮。 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
10.
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
11.
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
12.
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
13.
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
14.
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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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