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1.
企鹅珍珠贝游离珠培育技术的初步研究 总被引：4，自引：0，他引：4
2006 年 5 - 12 月,在广东省、湛江市、徐闻县芳华珍珠养殖场,采用贝龄 2 ～ 4 a 的企鹅珍珠贝作植核贝,以 1 ～ 3 a 贝作小片贝,进行游离珍珠培育试验.结果表明,植核母贝经 15 ～ 40 d 的术前处理,成活率为 95.33 % ～ 97.00 %;施术贝经过 6 个月培育后,吐核率为 63.00 % ～ 71.88 %,死亡率为 26.17 % ～ 35.00 %,成珠率为 1.95 % ～ 3.33 %.企鹅珍珠贝合适的植核母贝为 2 ～ 3 龄贝,小片贝为 1 ～ 2 龄贝. 相似文献
2.
大珠母贝游离珍珠培育研究 总被引：4，自引：0，他引：4
2008~2010年,在广西涠洲岛进行了大珠母贝(Pinctada maxima Jameson)游离珍珠培育实验。实验过程中采用解剖法优选植核核位、几种术前处理方法和低温处理小片贝制备外套膜小片等技术,旨在提高育珠贝留核率、成珠率和优珠率。结果表明,在大珠母贝内脏囊缩足肌左右两侧各有一个适合培育游离珍珠的核位,分别称为左袋和右袋,实际操作中只有左袋可以植入珠核培育游离珍珠;不同术前处理实验组的植核贝休养期成活率差异不显著(P>0.05),但留核率、成珠率显著差异(P<0.05),其中采用传统术前处理和低温处理相结合的综合术前处理方法可有效提高留核率、成珠率平均达78.2%和80.1%;低温处理小片贝与传统方法制备的大珠母贝外套膜小片的育珠效果(成珠率、优珠率、正圆珠比例)存在显著差异(P<0.05),且在实验温度范围内,成珠率、优珠率、正圆珠比例随处理温度的降低而增高,在4~8℃达到最好育珠效果,成珠率、优珠率和正圆珠比例分别达到98%、53%和30%左右;在术后休养期,植核贝吐核高峰出现植核后5~15 d,手术伤口愈合时间为15~20 d,育珠贝的死亡高峰出现在术后的第20~30天。在水温25~30℃条件下,珠核表面形成珍珠层的时间为45 d左右。 相似文献
3.
企鹅珍珠贝养成方式的初步研究 总被引：11，自引：0，他引：11
目前国内企鹅珍珠贝(Pteriapenguin)养殖尚不具规模,且都是沿用马氏珠母贝的养殖法[1]。作者在生产研究中发现企鹅珍珠贝中大贝足丝特别发达、粗壮,附着力特别强,用一般清贝刀很难将足丝切断,要将企鹅珍珠贝中大贝从养成笼(锥型笼)中取出,进行清洗换笼十分困难。为了改变这种局面,于1994年3月～1997年8月,作者在海南省陵水县湛江水产学院珍珠试验站进行了企鹅珍珠贝养成方式的初步研究。1 材料和方法1.1 试验贝取自湛江水产学院珍珠试验站人工养殖的企鹅珍珠贝。试验开始时贝龄0.5a,平均壳高6.4cm。一般认为企鹅珍珠贝幼苗下海养殖至壳高… 相似文献
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大珠母贝人工养殖过程中,幼贝死亡是一个严重的问题。1993年11月至1995年5月,采用现场调查、实验室研究和数理分析相结合的方法,在海南省临高县新盈珍珠贝养殖场自然海区吊养的A,B,C3批养殖贝和陵水新村珍珠贝养殖场养殖池吊养的D批养殖贝的发病和死亡情况进行了流行病学凋查.结果显示,大珠母贝幼贝群体的死亡是以暴发性方式发生,幼贝群体的大批量死亡高峰一般发生在4～6月龄期,8个月以后随着龄期的延长,死亡率显著降低.幼贝群体死亡率与贝体平均体长的关系是4cm以下的贝体死亡率较高,1～3cm阶段处于死亡高峰期内,5cm以上的贝体死亡率显著降低.大珠母贝幼贝群体的死亡率与类立克次体感染(即RLO平均感染严重度指数SI)之间存在显著的相关性,在RLO感染的高峰之后或当中部相应伴随贝群体死亡率的高峰,随着RLO感染的降低,贝群体的死亡率也明显降低。在4批养殖贝群体中,仅在A批养殖贝群体样本中发现有少量纤毛虫寄生(感染率为87.5%,感染强度为3.56个/10倍物镜).这几批幼贝群体的死亡与海水温度、盐度之间均无相关性。 相似文献
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北海鲱卵黄囊期仔鱼的摄食能力和生长 总被引：54，自引：1，他引：54
于1986年对大西洋鲱(clupea harengus L.)——北海种群卵黄囊期仔鱼在早期发育和饥饿期的摄食能力和生长作了实验研究。结果表明:(1)孵化后第6天(饲养水温13.1±0.4℃),仔鱼初次摄食,此时,卵黄容量从初孵时0.182mm~3降至0.020mm~3以下,眼、口、肠管、肛门、胸鳍等器官的功能基本形成,巡游模式建立;孵化后第8天,卵黄耗尽,混合营养期持续仅2天;不能建立外源性营养的仔鱼,第11天进入PNR期,第17天全部死亡。(2)仔鱼在不同饥饿阶段初次摄食率和摄食强度的变化式型是:开始较低,随即上升,高峰出现在卵黄耗尽后1—2天;此后就逐步下降;记录到的最高初次摄食率约为50％,最高摄食强度每尾仔鱼在4h内平均摄取3—4个轮虫。(3)仔鱼在初孵期的生长率平均为0.233mm/d;进入摄食期后,饥饿仔鱼的生长几乎停止;同期摄食仔鱼的生长率亦下降,为0.130mm/d;摄食仔鱼(N=309)在孵化后30天内的长度(L,全长)和日龄(d)的相关式为:L(mm)=0.180d+7.06。 相似文献
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不同因素对黑蝶贝插核的影响 总被引：1，自引：0，他引：1
黑蝶贝Pinctada margaritifera(Linne)插核存在的问题是手术后死亡多、脱核率高。为解决这个关键问题,作者把影响黑蝶贝插核的因素,即母贝性成熟度(A),排贝时间(B),插核部位(C)和术后休养方式(D)都联系起来,用正交表安排成四因素三水平试验。于1987年的试验结果表明:手术后的黑蝶贝,留核的最优条件为D_3C_3B_1A_2,即手术贝以贝笼休养,每贝插“左右袋”(二核),术前母贝处理14—16h,挑选性腺较丰满贝插核。 相似文献
8.
研究了3 种中药对合浦珠母贝(Pinctada fucata)插核手术后体重日增长速度、伤口的愈合效果及其对珍珠质量的影响。试验采用白藜芦醇、芦荟胶和云南白药对插核伤口进行单次处理(插核手术后及时处理)和3 次处理(手术后第5 天和第10 天分别进行第2 次和第3 次处理), 对体质量日增长速度、愈合率和珍珠质量进行统计分析。结果显示, 休养期各组体质量日增长速度变化趋势基本相同, 早期几乎全为负增长(0.06～?0.26 g/d), 第16 天基本恢复正常生长水平, 达到0.54～0.93 g/d, 后期云南白药单次处理组的增长速度最快(1.52 g/d), 显著高于对照组(0.34 g/d)(P<0.05), 但处理次数对体质量增长的影响不大。各试验组愈合率均较高, 10 天时试验组的愈合率达90%以上(90.7%～99.2%), 显著高于对照组(79.8%)(P＜0.05), 其中云南白药处理组的愈合率最高。各处理组的商品珠比例(87%~90%)均较高,但优质珠比例各组差异较大, 最高的是白藜芦醇和云南白药单次用药组, 分别为52.4%和54.8%。上述结果表明, 中药处理对伤口的愈合和珍珠质量具有一定的促进作用, 其中, 白藜芦醇或云南白药对伤口单次处理的效果最好。 相似文献
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马氏珠母贝术前处理与育珠研究 总被引：6，自引：0，他引：6
为了规范养殖行为,提高马氏珠母贝手术贝的成活率、成珠率和珍珠质量。2008年8月~2009年11月,在广东省湛江市徐闻龙之公司珍珠养殖基地,采用箩筐抑制法、塑料桶抑制法、变层法和淡水浸泡法进行了马氏珠母贝术前处理技术的研究。结果表明,术前处理结束后,各组间的成活率存在显著性差异(P0.05)。休养期育珠贝的成活率和留核率存在显著性差异(P0.05),成活率和留核率分别为57.1%~84.0%和54.9%~79.1%;育珠期育珠贝成活率和成珠率存在显著性差异(P0.05),成活率和成珠率分别为63.1%~75.1%和51.1%~70.1%。本实验结果表明经过淡水浸泡处理1h育珠效果最好。 相似文献
10.
为比较合浦珠母贝(Pinctada fucata)不同群体在高温胁迫下的存活及免疫酶活性变化情况,本实验以“海优1号”(YY)、“海选1号”(XX)、“南科1号”(KK)和广西潜在耐高温养殖群体(TT)为实验材料,通过渐变升温的方式测定4组合浦珠母贝在35℃水温胁迫下的生理指标,研究不同胁迫时长对合浦珠母贝存活及其鳃组织内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、总抗氧化能力(T-AOC)和碱性磷酸酶(AKP)活性的影响。研究显示,实验第8天开始出现个体死亡,TT组在实验12 d后存活率显著高于其余3组(P<0.05);4个群体的SOD、CAT和T-AOC活性随胁迫时间的延长大致呈上升-下降的趋势,在1～24 h内免疫酶活性呈上升趋势,在120 h后下降至对照水平以下;在高温胁迫下各组的AKP活性增加,KK、TT与XX、YY分别在12和24 h达到峰值,在120 h显著下降。本研究初步探明了高温胁迫下合浦珠母贝的免疫应答机制。 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
12.
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
13.
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
14.
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
15.
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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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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Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans 总被引：1，自引：0，他引：1
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
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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