哈氏仿对虾人工繁殖技术研究

哈氏仿对虾 (Ｐａｒａｐｅｎａｅｏｐｓｉｓｈａｒｄｗｉｃｋｉｉ(Ｍｉｅｒｓ) )属十足目 ,对虾族 ,对虾科 ,仿对虾属 (俗称滑皮虾、呛虾 )。据《浙江动物志》(甲壳类 )记载 ,该虾为近海性 ,中型虾类 (笔者调查体长大的达１２ｃｍ) ,生长于近岸７０ｍ以内 ,可栖息于各种不同地质的海底 ,在浙江海区夏季分布广 ,多密集于３０ｍ以内的沿岸水域。分布于我国黄海南部 ,国外分布于巴基斯坦、印度、新加坡、马来西亚等国。该虾产量高、肉质佳 ,供鲜食 (呛虾味道特别鲜美 )和制成海米 ,是浙江近海的重要经济种之一。是渔民１１月至翌年３月沿海拖虾…     

大连地区中国对虾“红腿病”病原体及其感染寄主细胞的电镜观察

对虾红腿病国内最早发现于１９８１年８月下旬山东潍坊市一养虾场,１９８８年８月在辽宁庄河、东沟县一带虾场开始流行［２］。此病流行广、发病期短、死亡率比较高,是危害对虾主要病害之一。作者自１９９０年８月～１９９２年９月,对大连地区养虾场流行的红腿病进行了调查、采样,并着重作了病原菌的形态及其侵染寄主细胞的病变观察,为虾病防治提供了科学依据。１材料与方法１·１材料来源典型对虾红腿病样品采自大连市金州区重家沟、营城区西小磨两个虾场。１,２样品的处理１．２．１病原菌的分离与菌种鉴定,病原菌的分离分别由辽宁…     

中国对虾红腿病药物防治应用试验

全身性细菌感染引起的红腿病，是一种重要的弧菌病，主要影响幼虾和成虾，发病率和死亡率都比较高，可以造成整池对虾在较短时间内出现大量死亡，是对虾养成期间危害严重的疾病之一。为了防治对虾红腿病，我们在室内进行了药物饵料筛选试验，在筛选的基础上，研制出复合抗菌药物（ＦＴＬ），在对虾养殖生产中进行了应用试验，获得了较好的防治效果。１材料和方法１．ｌ室内药物筛选试验试验用病虾１９９１年７月采自青岛黄岛区对虾养殖场，病虾体长约６．５ｃｍ，病症表现为游泳足、步足和其它附肢及尾扇变红。病虾取回后放于室内暂养，试验…     

中国对虾微孢子虫病的电镜观察

微孢子虫又称微粒子虫（Ｎｏｓｅｍａ），是微小的单细胞动物，分布广、危害大，已发现的种类有８００多种［１］，主要寄生于无脊椎动物和鱼类，特别是昆虫。在对虾疾病中，微孢子虫是所有寄生虫中危害最严重的一种。微孢子虫属于微孢亚门、微孢纲、微孢目、单丝亚目。寄生于对虾的微孢子虫属微粒子科（Ｎａｓｅｍａｔｉｄａｅ）；目前已报道４种微孢子虫寄生于对虾：奈氏微粒子虫（Ｎａｓｅｍａｎｅｌｓｏｎｉ）；对虾特汉虫（Ｔｈｅｌａｐａｎｉｐａｎａｅｌ）；桃红对虾特汉虫（Ｔｈｅｌａ－ｐａｎｉｐａｎａｅｌ　ｄｕａｒａｒａ）对虾…     

1993年青岛流亭镇对虾爆发性流行病调查

青岛流亭镇位于胶州湾东岸。对虾养殖面积６０００余亩，虾池３５０余个。从８０年代初开始养虾，产量逐年上升，１９９０～１９９２年达到全盛阶段，平均亩产２５０ｋg左右，最高可达５００kｇ，每亩净利达３０００～５０００元。虾池面积大多１０～２０亩，配备水泵２～３台（３００ｍ3／ｈ）。１９９３年暴发的对虾流行病［２］，流亭一带也未幸免于难，从７月２８日第一家因病出虾开始，到８月１０日前后仅１０余天时间，９０％左右的养虾户被追将虾出池，虾规格约８ｃｍ，平均亩产３０～５０ｋｇ．仅为往年的２０～３０％，直接经济损…     

不同虾种间肌肉组织蛋白质的比较

采用薄层等电聚焦凝胶电泳方法对罗氏沼虾（Macrobrachium rosenbergii)、绿须虾（Aristeus virilis)、长毛对虾（Penaeus penicillatus)、日本对（P.japonicus)、斑节对虾（P.monodon)和周氏新对虾（Metapenaeus joyneri）的肌肉组织蛋白质进行分离，检测各蛋白质组份及其等电点。根据蛋白质区带的共享度计算共相互间的遗传距离指数，然后用聚类方法处理数据，构建系统树，分析其间的差异程度，最后确定6种虾的亲缘关系。结果表明，每种虾可获得6－11条 蛋白质区带，等电点范围在4－6．95之间。虾类肌肉组织蛋白质组份及其电泳行为，可为虾类在分类学上的定位提供生化依据。     

暴发性流行病病原对中国对虾越冬亲虾人工感染的研究

从典型的白斑症病虾中,分离出一种杆状病毒,属对虾白斑病杆状病毒［３］。为了探讨对虾暴发性流行病的发病机理及传播机制,作者于１９９６～１９９７年冬季,采用青岛地区当年夏季暴发典型白斑症的病虾,对中国对虾健康的越冬亲虾进行了白斑病杆状病毒的感染试验。１　材料和方法１．１　病虾标本与病原分离具典型白斑症状的病虾,于１９９６年８月取自青岛城阳区红岛邵格庄发病的虾场,保存于－７０℃。剥离病虾的胃、肠及鳃组织约１０ｇ,加液氮充分研磨,加９０ｍｌ０．０１ｍｏｌ／ＬＰＢＳ（０．２ｍｏｌ／ＬＮａ_２ＨＰＯ_４－Ｎａ…     

台湾海峡及邻近海域6种对虾食性特征及其营养级研究

本文主要研究台湾海峡及邻近海域6种对虾的食性特征与营养级.研究结果表明,它们皆为混合食性型的甲壳动物.哈氏仿对虾、鹰爪虾和周氏新对虾的主要饵料生物属底栖生物和浮游动物生态类群,中华管鞭虾和须赤虾的主要饵料生物属浮游动物和底栖生物生态类群;它们的营养级范围在1.64～2.14之间.周氏新对虾、角突仿对虾、须赤虾和鹰爪虾属第二营养层次的杂食性动物,哈氏仿对虾和中华管鞭虾属第三营养层次的低级肉食性动物;它们的食物生境宽度范围为6.48～1.24,其大小范围依次为:哈氏仿对虾、中华管鞭虾、鹰爪虾、周氏新对虾、须赤虾、角突仿对虾;6种虾类之间的食物的重叠指数0.008～0.716.除了周氏新对虾与其它虾类之间食物的重叠指数<0.15外,其它5种虾类之间(食物的重叠指数0.387～0.716)都存在竞争饵料资源的问题.挠足类、长尾类、稚幼鱼、多毛类、硅藻类和肉足鞭毛虫是虾类共同争食的饵料生物.     

中国对虾精子和卵子受精能力的初步研究

１９７３年，Ｃｌａｒｋ等以褐对虾（Ｐｕｎａｅｕｕｓ　ａｚｔｅｃｕｓ）为实验材料，将解剖的卵子和精子混合，首次在非鞭毛型不动精子的人工授精研究中获得受精卵，受精率为１０％［２］。１９８６年，Ｍｉｎ－ＮａｎＬｉｎ等在雌虾产卵时，将精子滴入产卵池中使卵子受精，孵化率高达６３．１１［４］。关于中国对虾（Ｐｅｎａｅｕｓｃｈｉｎｅｎｓｉｓ）精子和卵子受精能力的研究还未见报道。精卵的受精能力直接决定受精率，而受精率的高低影响苗种生产。因此．进行对虾精子和卵子受精能力的研究有利于对受精过程的进一步了解，以使更好…     

浙江沿岸海域虾类优势种空间生态位分析

生态位与种间竞争、资源利用密切联系，体现了物种在群落中利用资源的能力。为探明浙江沿岸海域虾类分布格局的形成和影响因素，通过相对重要性指数确定了虾类群落优势种，分别采用Levins公式和Pianka指数计测了虾类优势种生态位宽度和生态位重叠，并通过典范对应分析（CCA）研究生态位分化情况。结果表明:研究海域共出现13种虾类优势种，根据生态位宽度大小将研究海域内的虾类优势种分为3类，细巧仿对虾、细螯虾、鲜明鼓虾和中华管鞭虾属于第一类群，以上4种虾类的空间生态位宽度较宽；日本鼓虾、哈氏仿对虾、鹰爪虾、中国毛虾和葛氏长臂虾属于第二类群，这5种虾类空间生态位略低于第一类群，但其生态位仍相对较宽；戴氏赤虾、脊腹褐虾、东海红虾和大管鞭虾这4种虾类的空间生态位较窄，属第三类群；生态位重叠指数变化范围在0.00~0.78，将重叠指数按照大于0.6、0.3~0.6和小于0.3划分为重叠度较高、重叠度较低和重叠度低3个重叠度等级，结果表明，虾类优势种生态位重叠以较低和低2个等级为主；虾类分布受水深、底层溶解氧和底层盐度的影响较大，受水温影响较小。虾类群落优势种空间生态位与生活习性、种间竞争、摄食以及海洋环境因子等多种因素有关。     

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.     

A Review of Some Environmental Issues Affecting Marine Mining

This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.     

Increased Particle Fluxes at the INDEX Site Attributable to Simulated Benthic Disturbance

Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.     

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.     

Determination of In Situ Sediment Shear Strength from Advanced Piston Corer Pullout Forces

The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.     

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.