杂色鲍与盘鲍杂交F1的早期生物学表现

比较研究杂色鲍(Haliotis diversicolor)(S)与盘鲍(H.discus discus)(J)正反交F1及其亲本自繁后代的卵裂速度和孵化速度,以及杂色鲍与盘鲍杂交F<,1>及杂色鲍自繁幼体的成活率.在22～23℃下,杂色鲍自繁后代的早期发育速度快于盘鲍自繁后代.杂色鲍和盘鲍2细胞期分别为授精后45.3...     

杂色鲍和九孔鲍三倍体的化学诱导

本文首次报道了用化学药物法（ＣＢ、咖啡因以及高ＰＨ高钙溶液）休克杂色鲍和九孔鲍受粗卵诱导产生三倍体的试验结果。结果表明,用ＣＢ诱导杂色鲍,三倍体诱导率高达５９．０￣７６．２％;用咖啡因诱导杂色鲍和九孔鲍,三倍体导率低,分别为３０￣２０％。本就它们在诱导中的作用机理进行了讨论。     

皱纹盘鲍三倍体生长的初步研究

将用低温休克法和细胞松弛素B诱导法,获得的皱纹盘鲍(Haliotis discus hannai Ino)三倍体诱导群与二倍体的个体,在室内同样条件下饲育,对其生长情况进行了比较,结果表明:(1)三倍体与二倍体的当年稚鲍在壳长和体重的增长上无明显差异。(2)三倍体与二倍体的2龄鲍,在第二年前期生长无明显差异,但从第二年后期开始,三倍体的壳长、体重增长逐渐优于二倍体。(3)统计学分析表明,三倍体与二倍体的3龄鲍在体重、软体部和足肌的增长方面,存在着明显差异。(4)在室内饲育19个月的鲍,三倍体诱导群的壳长比二倍体大10.2％,体重比二倍体大20.1％,足肌湿重比二倍体大17.6％。     

氯霉素暴露对杂色鲍免疫活性的影响

杂色鲍的免疫机能主要是由血细胞以吞噬的方式来完成．本研究将杂色鲍分别暴露在1、2、5Ixg／cm3不同含量氯霉素的水体中60d（每天暴露4h）,检测其主要免疫指标的变化．实验结果表明,经氯霉素暴露实验后,杂色鲍的主要免疫指标出现了下降．对照组与各药物含量组（1、2、5μg／cm3）中杂色鲍血细胞对溶藻弧菌的吞噬率分别为89．83％±3．66％、75．33％±4．89％、68．67％±5．05％和37．00％±9．21％;其吞噬指数分别为3．84±0．27、2．54±0．35、2．12±0．47和1．18±0．32;其血细胞密度分别为（2．72±0．33）×10’、（1．87±0．09）×10^7、（1．46±0．17）x10^7、（1．03±0．14）×10^7个／cmA^3．对照组与各药物含量组在水温3l℃高温胁迫下杂色鲍半致死时间（,Jk）分别为10、8、6、4h．各实验组的壳长、体重生长率、成活率与对照组比较,高含量组均显著小于对照组．含量为lμg／cm^3和2μg／cm^3的氯霉素暴露对杂色鲍的生长有轻微的促进作用．各实验组酸性磷酸酶（ACP）、碱性磷酸酶（AKP）、超氧化物歧化酶（SOD）的酶活指标变化与氯霉素的暴露含量无明显相关性．     

耳鲍人工养殖的可行性研究

经过1a的养殖实验，研究了耳鲍（Haliotis asinina)在海南省人工养殖的可行性，发现室外水泥池池底波纹板流水养殖，其生长速度快，年平均壳长增长率为75．5％，成活率高达83．3％，比我省主要鲍鱼养殖品种九孔鲍和杂色鲍年平均壳长增长率分别高了13．8％和13．5％，成活率高了31．7％和30％，同时证实耳鲍不适合室内目前通用的工厂化笼养。     

杂色鲍与皱纹盘鲍!盘鲍杂交的初步研究

于1998～1999年在福建厦门和东山两地养殖场，对我国主要养殖鲍即杂色鲍与皱纹盘鲍、盘鲍进行杂交试验。结果表明，皱♂×杂♀的受精率为3．5％～15．0％，平均7．6％。皱♀×杂♂的受精率为1．5％～4．0％，平均2．8％。杂交成功的受精卵的胚胎和幼体发育均正常。杂色鲍×盘鲍杂交组合的受精率明显高于杂色鲍×皱纹盘鲍，无论哪个组合杂色鲍作为雌性亲本的杂交受精率均比反交大大提高。     

温度对杂色鲍不同群体生长率与存活率的影响

在16、20、24和28℃这4个设定的水温下,以杂色鲍（Haliotisdiversicolor）日本群体、台湾群体、越南群体和“东优1号”为材料,进行为期40d的养殖试验,对4个杂色鲍群体在不同温度下的壳长日增长率（LGR）和体重日增长率（WGR）进行比较．结果表明,“东优l号”杂色鲍群体在28℃时的LGR和WGR值分别达到162．23±15．79lxm／d和46．52±6．89mg／d,在4个温度下的LGR和WGR值都优于其他3个群体,台湾群体在较高温度（24和28℃）条件下的LGR和WGR值要高于日本群体,而日本群体在较低温度（16和20℃）时的值则高于台湾群体．双因素方差分析的结果进一步表明,温度对杂色鲍不同群体的生长率指标具有显著影响．     

杂色鲍血蓝蛋白HtH1基因第16内含子SNP密度的分析

单核苷酸多态性（SNPs）是继RFLP和SSR多态性标记之后的新一代遗传标记系统.本文采用EPIC的方法,分析了45个杂色鲍样品的血蓝蛋白HtH1基因第16内含子（H1 intron 16）的SNP数据.这45个个体分别来自日本、台湾和汕头3个不同海域的野生或养殖群体.日本群体的血蓝蛋白HtH1基因第16内含子呈现出长度多态性,共有3种不同长度,分别是1 900、780、440 bp,测序结果表明3个等位基因可以互相比对;而台湾和汕头杂色鲍养殖群体的均为1 900 bp.初步研究结果表明日本杂色鲍个体大约96 bp长的片段含有1个自身杂合SNP位点;台湾杂色鲍个体约133 bp含有1个自身杂合SNP位点;汕头杂色鲍个体约153 bp含有1个自身杂合SNP位点.13个台湾杂色鲍个体包含的SNP密度为约31 bp含有1个SNP;23个汕头杂色鲍个体包含的SNP密度为约21 bp含有1个SNP.这些数据表明现有的杂色鲍养殖群体包含了丰富的SNP位点,利用SNP分子标记进行高密度遗传图谱的构建是可行的.     

中国海耳鲍胚胎发育特征

利用显微技术对耳鲍(Haliotis asinineLinnaeus)的胚胎发育进行了研究,同时观察到孵化后的担轮幼虫。结果表明,耳鲍胚胎发育过程与皱纹盘鲍(Haliotis discus hannai)和杂色鲍(Haliotis diversicolor)基本相似,胚胎发育过程分为受精期、第一极体放出期、第二极体放出期、2细胞期、4细胞期、8细胞期、16细胞期、32细胞期、桑椹期、原肠期和未孵化的担轮幼虫期。在海水质量密度1.024,水温28℃的条件下,耳鲍完成胚胎发育历时约5 h 30 min,比皱纹盘鲍(海水质量密度1.022～1.023,水温22.5℃)、杂色鲍(海水质量密度1.022～1.023,水温24～26℃)分别快1.5～2.5 h和0.5 h。耳鲍成熟卵卵径为0.18～0.19 mm,担轮幼虫具有1束顶毛和2个纤毛环带。     

华贵栉孔扇贝三倍体的研究

本文报道了用细胞松驰素B、高温和低温休克等方法诱导华贵栉孔扇贝（Chlamys nobilis）三倍体的实验结果。在26.0～28.0℃条件下，选用不同浓度的细胞松驰素B0.1、0.3、0.5、0.7和1.0mg/dm^3，在受精后15min，处理受精卵15min，三倍体诱导率分别为12.5%、37.5%、68.0%、66.6%和81.0%，其中0.5～1.0mg/dm^3浓度的细胞松驰素B对改变倍性最有效。高温休克选用31.0、33.0、35.0和37.0℃处理受精卵，最高三倍体诱导率达46.7%（33.0℃,处理15min）。低温休克选用6.0、8.0、10.0和12.0℃处理受精卵，最高三倍体诱导率为40.7%（10.0℃，处理20min）。实验结果表明，随着处理强度的增大和处理时间的延长，三倍体诱导率增高、但孵化率下降，畸型率上升。用高温休克处理的实验组幼虫生长速度较对照组快。作者认为，在商业性生产中，温度休克是诱导扇贝三倍体的一种简便、有效的方法。文中还就细胞松驰素B与温度休克诱导三倍体的机制进行了讨论。     

Microbial Biomass and Organic Nutrients in the Deep-Sea Sediments of the Central Indian Ocean Basin

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.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

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。     

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.     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

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.     

Deep-Sea Sediment Compression Curves: Some Controlling Factors, Spurious Overconsolidation, Predictions, and Geophysical Reproduction

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.     

INFORMATION FOR AUTHORS

<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,     

Evaluation of the Risk of Marine Slope Instability: A Pseudo-3D Approach for Application to Large Areas

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.