吸虫纲半尾科指腺属吸虫两新种

本文报告寄生于海洋鱼类指腺属（Lecithochirium）吸虫两新种，即福建指腺吸虫，新种L．fukenensissp．nov．，虫体大小1．31～3．46×0．426～1．05（2．69×0．737），虫卵16～23×8～13（19×10）；狗母鱼指腺吸虫，新种L．tra－chinocephalisp．nov．，体部2．48×0．75，尾部1．10长，虫卵20～25×14～17（22．8×15．7）。     

长江口区鱼类的复殖吸虫

中国科学院海洋研究所于1985-1986年进行长江ロ渔业资源生物本底调查,作者对渔业试捕中所获鱼类作复殖吸虫检查,先后共四次,解剖鲜鱼497尾，发现吸虫14种(含褶膜吸虫未定种和芽腺吸虫幼虫),其中有2个新种,均属半尾科 Lemuridae (Looss，1899)Luhe,190l。新种模式标本保存在中国科学院海洋研究所。本文虫体各部分测量一律为mm,卵子为μm。     

鲻鱼体内单睾椭囊吸虫的种群生态研究

鲻鱼肠内的单睾椭囊吸虫Elliptobursa singlorchis随着宿主体长的增长，其感染率、感染强度和种群平均密度呈逐渐增加的趋势；其中群平均拥挤度、扩散性指标随着体长的增长亦有显著的增加，而负二项参数则在0．13－0．34之间呈不规划的变动；在春夏秋3季，吸虫在宿主鲻鱼体内的感染率逐渐降低，冬季又显著增加，而感染强度和种群平均密度在一年四季中则变化不大。吸虫种群在不同体长组的鲻鱼体内均为聚集分布，而且聚集强度随种群密度的增加而增强。吸虫种群在一年四季中的鲻鱼体内的时空分布亦为聚集分布，聚集强度变化不大。     

单孔科拟囊腔属吸虫一新种

拟囊腔吸虫 ,新种Saccocoelioideslizaesp .nov .发现于棱　Lizacarinatus的消化道 .同已知种相比 ,无论虫体大小还是各器官的形态结构及分布 ,新种与S .magniovatusSzidat,1 954和Saccocoelioidesbeauforti(Hanter&Thomas,1 961 ;Over streef,1 971 )最为相似 .但S .magniovatus没有前咽 ,虫卵 (0 .0 95～ 0 .1 1 4× 0 .0 41～ 0 .0 60 )较大且卵黄腺几乎呈“V”形 ;而Saccocoelioidesbeauforti的食道较长 ,肠叉位于腹吸盘之后 ,肠管止于卵巢之后 ,虫卵里的毛蚴不具眼点 .     

鱼类消化道细菌及其作用的研究Ⅰ.黄鳍鲷

本文报道了从黄鳍鲷消化道中分离细菌的数量与组成。结果表明，好气异养细菌9．0×105～8．3×107个／g。其中含见丁质分解菌3．8×105～3．7×106个／g，弧菌1．1X10’～1．8×104个／g。共分离232株细菌。其种群组成为弧菌、不动杆菌、气单胞菌、假单胞菌、埃希氏菌、无色杆菌、节细菌和链球菌等8属。并测定其生。特性，表明该类菌对多种有机质具有强的分解能力，这些特姓有利于鱼类对营养物质的消化和吸收，促进其生长。     

黄海北部海域沉积物反硝化细菌数量及反硝化速率的季节变化

用乙炔抑制法和最大或然数（most probable number,MPN）法对黄海北部海域沉积物反硝化速率及反硝化细菌数量的季节变化进行了研究,结果表明,该海域反硝化速率在夏季最大,范围在3．2～7．5μmol／（m^2·h）之间,平均值为4．85μmol／（m^2·h）;而在春、秋季其范围分别为0．26～2．65μmol／（m^2·h）和1．21～4．12μmol／（m^2·h）。该研究海域3个季节反硝化细菌数量差别较大,春、夏、秋季分别在1．78×10^4～8．12×10^4,1．18×10^6～6．18×10^6和0．72×10^5～4．50×10^5个／g之间。春、秋两季反硝化速率和反硝化细菌数量之间呈显著性正相关,相关系数分别为0．759和0．750（P〈0．05）。本结果可为黄海北部海域氮循环机制研究提供重要参考。     

三叶寡腺吸虫(半尾科)新属、新种的描述

作者整理1964年在海南岛沿海采集的吸虫标本时,发现一种半尾科Hemiuridae宫腺亚科吸虫的新种,其体形及内部器官与该科已知各属特征迥异,应建立新属,现记述如下: 所有测量一律为毫米,卵子为微米。模式标本保存在中国科学院海洋研究所。     

厦门西港浮游植物吸收磷酸盐的粒级特征

厦门西港微型浮游植物（3～20μm）吸收磷酸盐的百分比、吸收速率常数和单位体积吸收速率均最大，分别为74．85％、8．28×10-5／s和5．38×10-5μmol／（dm3·s），小型浮游植物（20～200μm）次之，超微型浮游植物（0．2～3μm）最小；单位叶绿素a的吸收速率是超微型浮游植物最大[5．38×10-5μmol／（μg·s）]，微型次之，小型最小。相关分析表明各粒级浮游植物吸收磷酸盐的百分比与相应粒级浮游植物的叶绿素a含量和光合速率的百分比呈良好的正相关关系。     

南海水体三项无机氮含量的垂直变化特征及与其他环境要素的相关性

据南海环境调查资料，研究了南海水体NO3-N、NO2-N、NH4-N、DIN含量及无机氮组成的垂直变化规律．结果表明：NO3-N、NO2-N、NH4-N、DIN含量范围和均值分别为0．00～43．9，12．32；0．00～1．69，0．07；0．17-14．87，1．32；0．35～45．92，13．73μmol／dm^3．其含量分布与垂直变化特征与深海、大洋的相似，表明南海水是太平洋的变性水体．NO3-N、DIN含量的垂直分布跃层出现于75～500m间，夏季的跃层强度分别为6．61X10-’、6．68×1012Ixmol／（dm’·m），冬季的均为5．65×10^-2μmol／（dm^3·m）；NO2-N含量的最大值多出现于75～100m之间，NH4-N含量的最大值出现在0m层．在浮游植物活动较旺盛的真光层中，NH4-N为无机氮的主要存在形态（平均占比为64．4％）．真光层以下NO3-N为无机氮的主要存在形态（平均占比≥90．8％）．对三项无机氮含量与其他生源要素、水文因子的相关分析结果表明，NO3-N含量与PO4-P、TDP、TP、SiO3-Si、S均呈显著正相关，与pH、DO、O2％、t则呈显著负相关．     

细尾属吸虫—新种

从大头狗母鱼Trachinocephalusmyops的消化道内检获细尾属1新种：厦门细尾吸虫，新种Eriepturusxiamenensissp.nov.。新种与狗母色细尾吸虫E.trachinocephaliYamaguti，1970和带鱼细尾吸虫E．trichiuriGuetShen，1978相似，但它们可以从虫体大小和虫卵大小以及其他形态特征相区别。     

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.     

Assessing the Validity of Seismo-Acoustic Predictor Equations for Obtaining Seabed and Sub-Surface Sediment Physical Properties

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.     

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.     

Interannual Sea Level Variations and Annual Tides in the Northwestern Pacific

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.     

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.     

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.     

Flow Cytometric Analysis of Coastal Lagoon Bacterioplankton and Picophytoplankton: Fixation and Storage Effects

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.