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1.
青蛤催产的研究   总被引:7,自引:0,他引:7  
本研究对青蛤(CyclinasinensisGemlin)进行人工催产,获得大批量成熟卵子,室内人工育苗试验获得成功。1987~1996年,作者分别在启东和大连进行了百余次的催产效果研究,最后筛选出一种特有效的综合催产方法,催产有效率达95%以上。1 材料1.1 亲贝来源在青蛤繁殖盛期,从自然海区内采捕个体完整、健壮,性腺发育肥满的成贝作为亲贝。1987~1992年亲贝取自启东近海乡沿海滩涂;1994~1995年亲贝采捕于大连金州区登沙河乡沿海滩涂;1996年亲贝取自启东盐场水库,重复扩大试验。1.2 容器、水质和其他材料1987~1992年,属初试阶段,用塑料盆和塑料桶作…  相似文献   

2.
本文报告了彩虹明樱蛤Moerellairidescens在人工育苗过程中的人工催产技术,比较了几种催产方法的催产效果,其中以0.5×10-3氨海水浸泡刺激效果最好。催产的成功与否与亲贝性腺发育程度关系密切。此外,本文简要讨论了几种催产方法对不同双壳贝类的使用结果,对亲贝生殖腺寄生虫影响亲贝性腺作了简单观察。  相似文献   

3.
斜带髭鲷人工催产技术研究   总被引:3,自引:0,他引:3  
斜带髭鲷(HapalogenysnitensRichardson) ,隶属于石鲈科髭鲷属 ,系浅海中下层鱼类。由于其生长速度快、肉质细嫩 ,且市场销路好、价格高 ,近几年深受福建、广东等地广大网箱养殖户的青睐。1995年以来 ,一些单位和不少的个体育苗场相继开展了人工繁殖、育苗的研究及开发工作。但有关报道很少 ,在亲鱼培育、催产及人工育苗方面的技术尚不成熟 ,作者于1998~2000年进行了亲鱼的培育及人工促熟催产实验 ,并取得较好的结果。现将研究结果报告如下 ,以期为斜带髭鲷大规模的人工育苗提供有关的基础数据和…  相似文献   

4.
研究了脉红螺(Rapana venosa(Valenciennes)在室内人工投喂条件下的亲螺交配、卵袋产出、孵化、幼虫培育、采苗。结果为:亲螺促熟培育的适宜饵料是四角蛤蜊,在人工促熟条件下每只雌螺产卵量44.57万粒,胚胎孵化率平均为87.4%;在育苗期间,幼虫前期密度为0.2个/mL,后期0.1个/mL,投喂金藻、小球藻、角毛藻,当平均壳高达到1200μm以上时,投放附有底栖硅藻的聚乙烯波纹板采苗效果最好。本文在稚螺培育中主要研究了脉红螺稚螺食性转换和变态过程中的适宜动物性饵料,以及不同处理方法的附着基对稚螺附着的影响,结果表明:经亲螺爬过和附有底栖硅藻的波纹板,附苗效果好;刚附着变态后稚螺除了投喂牡蛎肉糜外,定期向池内投放活的牡蛎受精卵,可以促进稚螺变态和食性顺利转化,成功培育出壳高1.0cm以上苗种。  相似文献   

5.
本文以海大2号长牡蛎新品种为材料,通过强化亲贝金黄壳色选择和人工升温促熟培育,使海大2号长牡蛎亲贝成熟,利用阴干、升温刺激方法诱导产卵;通过控制幼虫密度、投喂新鲜的单胞藻等技术措施,幼虫快速生长发育到眼点幼虫,投放栉孔扇贝壳进行采苗,眼点幼虫的附着变态率达到48%,成功培育出壳高0.5mm以上的壳色金黄稚贝4.68亿粒,单位水体出苗量达到30×10~4粒/m~3。同时进行与普通牡蛎在亲贝促熟培养、幼虫生长发育方面比较实验,海大2号长牡蛎在亲贝促熟培育方面比普通牡蛎发育慢,但幼虫期在生长速度和成活率表现较明显的生长优势和较高的成活率,显示出海大2号长牡蛎新品种生长的优越性。  相似文献   

6.
本文根据缢蛏的生态习性和摄食特点等,设计了缢蛏亲贝模拟自然生态暂养方式,与挂笼暂养及底播暂养等进行了比较试验,并对暂养亲贝的性腺发育情况进行了比较观察。结果发现,模拟自然生态暂养蛏成活率明显高于挂笼暂养和底播暂养,且亲贝暂养促熟效果明显。另外,作者对缢蛏的人工催产方法等进行了比较试验,结果发现,阴干──低温处理对缢蛏亲贝具有良好的催产效果,其排卵率可达68%。  相似文献   

7.
大珠母贝人工育苗技术的研究   总被引:9,自引:0,他引:9  
研究大珠母贝人工育苗若干技术,提出一些技术措施:亲贝强化培育促熟,人工诱导排放精卵,优选幼虫,投喂适口的饵料,适时倒池以及投放合适的采苗器等。结果表明,平均单产壳高2-3mm的幼苗8.1万粒/m3,最高可达9.3万粒/m3。  相似文献   

8.
砗蚝(Hippopus hippopus)的人工繁育   总被引:1,自引:0,他引:1  
于2016年4—9月开展了砗蚝(Hippopus hippopus)人工繁育技术研究。采用五羟色胺进行催产、促使配子排放;精卵分别收集,进行异体间受精以避免自交;受精卵经过30h孵化,选出600万D形幼虫进行培育。砗蚝的早期生活史与砗磲(Tridacna spp.)相似,经历前期面盘幼虫、中期面盘幼虫、后期面盘幼虫、足面盘幼虫、单水管稚贝、双水管稚贝、外套膜触手稚贝、幼贝等阶段。与砗磲不同的是,砗蚝怀卵量较少,但卵径较大,D型幼虫也较大,幼虫趋光性更强,壳长2.0mm以后外套膜不伸出壳缘外,幼贝贝壳形态也不同于砗磲。同砗磲幼虫一样,砗蚝幼虫需要构建虫黄藻系统之后,才能出现鳃、次生壳等,从而完成变态成为稚贝。砗蚝幼虫变态率较低,仅为1.4%。中间育成期间,丝状藻和锥形螺是稚贝培育的主要敌害,需及时清理才能确保稚幼贝正常生长发育。经过120d的精心饲育,培养出平均壳长6.3mm幼贝500余个。本研究为进一步开展砗蚝人工繁育、中间育成、增殖放流、资源修复及移植保育提供了参考。  相似文献   

9.
大黄鱼(Pseudosciaena crocea)人工苗种生产中,所使用的一般是经过人工养殖、强化促熟的亲鱼。这种亲鱼需要用外源激素进行人工催产才能产卵。然而,经催产的成熟亲鱼经常出现有时产卵率高,有时产卵率低,有时甚至因滞产而死亡等,其产卵效果很不稳定,因而不利于生产。有关外源激素剂量对大黄鱼催产效果影响的研究,目前尚未见过报道。本文主要介绍这一试验结果,并就激素含量与卵巢成熟系数之间的关系等进行探讨,旨在为今后大黄鱼及其他鱼类种苗生产提供参考。1材料与方法1.1材料1.1.1亲鱼试验用亲鱼均…  相似文献   

10.
象拔蚌人工育苗技术研究   总被引:2,自引:1,他引:1  
通过对亲贝促熟、人工催产、幼虫培育和采苗等技术环节的研究,建立了象拔蚌(Panopea gen-erosa)的人工繁育技术。研究表明,在盐度28~30条件下,受精卵在水温11、13、16oC时发育至D形幼虫所需时间分别为83、60和46 h;在水温16~18oC,经20 d发育至壳长约380μm的壳顶幼虫时出现足和水管原基,进入附着变态阶段。投放附着基后培育约70 d,可生长至壳长5 mm的幼贝。壳长日增长量在D形幼虫阶段为6.2μm,在壳顶幼虫阶段为16.8μm,附着变态后生长速度加快,外形具成体形态。不同附着基的采苗率依次为:细砂>卵石>聚乙烯网片>波纹板。  相似文献   

11.
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   

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.
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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A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.  相似文献   

17.
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,(8):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   

20.
This article presents a methodology developed to evaluate the instability of submarine slopes that extend over a large area. Special attention was paid to (1) the complex geometry (bathymetry) and the expanse of the slope, (2) the heterogeneity of the sediment, and (3) the distribution of the pore pressure. The safety factor was considered as a spatially varying quantity. The General Formulation (GLE, Fredlund and Krahn 1977), which fully satisfies equilibrium conditions, was used for evaluating the stability of the marine slope. The submarine slope failure, which occurred on 16 October 1979 during the construction of the new Nice airport, was studied in order to test the developed model. Geotechnical parameters were taken from experimental tests carried out by IFREMER on 19 cores extracted at different depths (from 27 m to 1300 m) (Cochonat, Bourillet, and Savoye, 1993; Mulder et al., 1994). Many scenarios were proposed in order to explain the cause of the Nice slope failure (Habib, 1994). In this article, two of those scenarios were tested. Simulation results are presented and discussed.  相似文献   

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