欧洲鳗鲡的性分化和僵鳗成因的探讨

欧洲鳗鲡性分化时间在白仔鳗转变为黑仔鳗时期体长１０．５－１２．０ｃｍ,性腺切片观察可见雌性卵巢中有原始卵原细胞雄性生精小管中有精原细胞,性别分化明显旱鳗鲡从福建省两个养鳗场采集僵鳗,取甚生腺切片观察有精原除个别僵鳗外,全部为雄性,提示僵鳗成因可能与性别有关。文中讨论了发生僵鳗的复杂因素。     

养殖牙鲆鳗弧菌疫苗的研究

以牙鲆病原性鳗弧菌M3为抗原,制备了细胞（CV）、细胞－胞外产物（CEV）、脂多糖（LPS）三种疫苗,通过浸泡和注射两种途径对牙鲆进行两次免疫,检测疫苗的免疫保护效果。免疫后4周可检测到免疫组牙鲆具有明显的凝集抗体效价,其中注射组效价显著高于浸泡组,而对照组变化不明显。与对照组相比,免疫组牙鲆获得良好的免疫保护力,其中注射免疫组高于浸泡组。在注射免疫途径中,以CEV的免疫保护效果最好;在浸泡免疫途径中,以CEV和LPS的免疫保护效果最好。结果表明鳗弧菌M3的细胞－胞外产物苗有显著的免疫保护作用。     

僵鳗促长饲料养殖日本僵鳗及欧鳗的效果

将僵鳗促长饲料分别按１％￣２％比例添加于常规鳗鱼配合饲料中进行了养殖日本僵鳗及欧鳗试验。结果表明,饲料效率日本僵鳗添加组比对照组提高了３１％￣４０％;欧鳗添加组比对照组高出６８．９％￣２５０％。成活率日本僵鳗添加组高于或等于对照组;欧鳗添加组比对照组高出５２％￣６２％。养殖每公斤鳗的饲料成本,日本僵鳗添加组比对照组下降了１３％￣２０％,而欧鳗添加组比对照组下降了３６％￣５４％。证实了用僵鳗促长饲料     

母源免疫对大菱鲆(Scophthalmus maximus)子代抗体IgM水平的影响

采用鳗弧菌灭活疫苗对大菱鲆(Scophthalmus maximus)雌性亲鱼免疫方法, 进行了母源免疫对子代抗体水平、变化规律的影响及卵子中抗体蛋白空间分布特征的研究。结果表明, 免疫亲鱼产出的卵子中IgM抗体水平显著高于对照组。胚胎发育过程中, 抗体水平整体呈下降趋势, 且48h前下降迅速, 免疫组抗体水平显著高于对照组(P<0.05); 48h以后, 免疫组和对照组间无显著差异。卵子中抗体蛋白免疫组化定位结果表明, 未受精卵中IgM抗体集中分布在卵膜内侧边缘, 卵黄部分分布不明显。研究还发现, 卵巢液中抗体水平显著高于卵子匀浆液, 且免疫亲鱼组卵巢液中抗体水平显著高于对照组(P<0.05)。本实验验证了大菱鲆特异性抗体的母源传递性, 并揭示了在本免疫条件下的传递时效, 为进一步开展通过母源免疫对育苗早期疾病防控途径的探索奠定了基础。     

对虾鳗弧菌卵黄抗体(IgY)的制备及其对人工感染的保护研究

以纯培养的鳗弧菌作为抗原,探讨对虾鳗弧菌(Vibrio anguillarum)卵黄抗体(IgY)的制备技术,以及IgY在对虾体内的代谢及对人工感染和自然感染弧菌病的保护作用。结果表明:鳗弧菌对蛋鸡有较好的免疫原性,产蛋鸡经免疫后,血清与卵黄中很快出现抗体,而且卵黄中的抗体水平要高于血清中的抗体水平。IgY对鳗弧菌的感染有可靠的保护作用,IgY经口服后很快到达直肠,继而血淋巴、肝胰脏中也出现抗体,并可持续12~24 h;投喂IgY的试验组对虾在7 d内的死亡率为15%,极显著地低于对照组对虾的同期死亡率(为60%)。     

闽南—台湾浅滩渔场的叶状仔鳗形态比较

本文首次报道１９８７年１１月至１９８８年１１月在闽南－台湾浅滩渔场采获的９种叶状铒１鳗，它们分别属于３个科；鸭嘴鳗科３种，锯犁鳗科１种，蛇鳗科５种。文中描述、比较了研究叶状仔鳗的主要形态特征。     

鳗饲料添加螺旋藻粉的养殖效果

本文报道了用Ｓｐｉｒｕｌｉｎａ ｐｌａｔｅｎｓｉｓ粉添加于“厦清”、“大昌”牌养鳗饲料中喂养日本鳗苗的试验。结果表明,添加该藻粉２．０％喂养僵鳗３０ｄ,其饲料系数比对照组均下降,降幅为２１．２％￣５３．７％,鳗增重倍数提高０．０２９￣０．１７１;添加该藻粉２．５％￣２．０％喂养正常幼鳗１１８ｄ,其饲料系数分别降低０．０７４￣０．２３４和０．０２４￣０．１８１,且鳗个体均匀,规格较大。     

饥饿对斜带石斑鱼稚鱼胃肠道内分泌细胞的形态、定位和分布密度的影响

对斜带石斑鱼（Epinephelus coioides）稚鱼在摄食和饥饿2种营养条件下胃肠道中5种内分泌细胞的形态、定位和分布密度进行比较研究.采用免疫细胞化学方法和5-羟色胺（5-hydroxytryptamine,5-HT）、生长抑素（somatostain,Som）、胃泌素（gastrin,Gas）、P物质（substance P,SP）及神经肽Y（neuropeptide,NPY）的特异性抗血清进行胃肠道免疫活性细胞的检测.结果显示,5种胃肠激素内分泌细胞在斜带石斑鱼稚鱼胃肠各部位均有开放型和封闭型2种,饥饿对细胞的形态有所影响但不明显.统计分析结果显示5种内分泌细胞在摄食组和饥饿组的斜带石斑鱼稚鱼胃肠各部位的分布密度存在明显差异.在贲门胃,饥饿组5-羟色胺和生长抑素免疫活性细胞数量上升,为正常摄食组的2.2倍和12.4倍,而在胃体和幽门胃则下降了1/3～5/6;饥饿组的胃泌素和P物质免疫阳性细胞数量在幽门胃下降为1/2,在肠道则有升有降;唯有神经肽Y免疫活性细胞在摄食组和饥饿组2组间没有显著差异.这些结果表明,胃肠激素参与调控斜带石斑鱼稚鱼胃肠的消化和吸收功能.一旦发生饥饿,斜带石斑鱼稚鱼胃肠激素细胞的分泌活性发生相应改变,最终可能会导致细胞功能失调,成为幼体死亡的因素之一.     

鲈鱼鳗弧菌病疫苗的制备及免疫防治效果

以从患出血、烂尾病的鲈鱼 ( L ateolabrax japonicus)中分离的 1株致病性鳗弧菌 W- 1( Vibrio anguillarum)为材料 ,进行了鳗弧菌全细胞灭活疫苗研制 ,比较了福尔马林、苯酚、氯仿等不同灭活剂在不同温度下的灭活效果。最终确定以 0 .5 % ( v/ v)的福尔马林溶液在 2 8℃下处理 4 8h为最佳灭活条件 ,所用的菌悬液浓度为 2 .5× 10 9cfu/ m L。用福尔马林灭活的 W- 1( Vibrio anguil-larum)疫苗 ,分别浸泡免疫鲈鱼苗和注射成鱼 ,并检测了疫苗对鱼体的免疫保护力。结果表明 ,经疫苗浸泡免疫 4周后的鲈鱼苗免疫保护力达 64.7% ,90 d后同批次的鲈鱼再注射免疫 ,其免疫保护力为 78.9% ,血清中抗体凝集效价为 1∶ 192。仅进行注射免疫组 ,其免疫保护力为 5 7.9% ,血清中抗体凝集效价为 1∶ 2 2 4。     

牙鲆胃肠道及肝脏GnRH受体的免疫组织化学研究

利用免疫组织化学ABC法，对牙Ping胃肠道及肝脏促性腺激素释放激素（GnRH）受体的表达及分布特点进行了研究。结果显示：胃肠道粘膜上皮、腺上皮及肝细胞呈GnRH受体免疫反应阳性，阳性反应物分布在细胞膜和细胞质中，细胞核呈阴性反应。提示：牙Ping胃肠道上皮细胞及肝细胞能够表达GnRH受体，说明GnRH可能通过其受体影响牙Ping消化系统的功能。     

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,     

Estimation of Sediment Properties during Benthic Impact Experiments

Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.