鲈鱼土池人工育苗研究

报道了１９８９－１９９３年鲈鱼土池人工育苗的研究结果，捕自天然海区、围垦内 网箱培育的亲鱼注射ＬＲＨ－Ａ与ＨＣＧ诱导能顺利排卵，产卵率７０－１００％，受精卵卵径１．２５－１．４０ｍｍ，浮性卵、受精率２１－８９．０％，在水温１８．０－２１．２℃、盐度３１．０－３４．０的条件下，一般经５０．６７ｈ孵出仔鱼，孵化率４６．０－９０．０％。人工育苗在室外土池进行，最高成活率１１．７％。初孵仔鱼全长３．５３－     

红鳍东方Tun人工育苗技术的初步研究

１９９６年从日本引进３ｋｇ红鲁东方Ｔｕｎ受精卵，在福建省宁德市进行人工育苗技术研究，孵出仔鱼７０万尾，孵化率３８．９％，培育出平均全长２．９９ｃｍ的幼鱼１８．５万尾，育苗成活率２６．４％，并对人工育苗的关键技术进行了探讨。     

鲻鱼人工繁殖研究

本文报道了１９９１￣１９９５年间鲻鱼人工繁殖的研究结果。池养亲鱼经注射ＬＲＨ－Ａ及ＨＣＧ诱导能顺利排卵，亲鱼成熟率６２．７％￣９０％，产卵率６２．５％￣１００％，受精率２０％￣７５％；受精卵浮性，卵径８４０￣９２０μｍ，在水温１９￣２０℃、盐度２６．６￣２８．０、ｐＨ值７．９１￣８．２５的条件下，一般经４９￣５３ｈ孵出仔鱼，孵化率４８％￣７３％，１９９１￣１９９５年度分别孵出仔鱼１０．０、８４．１     

红鳍东方鲀人工育苗技术的初步研究

1996年从日本引进3kg（约180万粒）红鳍东方受精卵，在福建省宁德市进行人工育苗技术研究。孵出仔鱼70万尾，孵化率38．9％，培育出平均全长2．99cm的幼鱼18．5万尾，育苗成活率26．4％，并对人工育苗的关键技术进行了探讨。     

利用单胞藻培养池进行真鲷育苗技术

１９９３年，于文登市小观海珍品育苗养殖场，在海湾扇贝和对虾育苗结束后，利用其配套的单胞藻培养地进行真鲷育苗，利用对虾育苗池和卤虫孵化池培养轮虫。在不增加任何设备的前提下，育成全长３．０１～６．５０ｃｍ，平均全长３．４４ｃｍ的真鲷商品鱼种１６１１１６尾，从仔鱼培育到商品苗种的成活率达到２４．７２％，平均单位水体出苗量达到２６８５尾，１９９３年７月１９日通过了文登市科委组织的验收。正材料和方法１．１育苗设施亲鱼产卵池（１个）和鱼苗培育池（６个）皆用单胞藻培养池（规格为３．８ｍ×３．７ｍ×０．８ｍ，水…     

Mian状黄姑鱼早期发育阶段的摄食与生长特性

１９９７年４－５月,在集美大学水产学院海水育苗试验场。采用生态学方法对人工培育的Ｍｉａｎ状黄姑鱼仔、稚、幼鱼的摄食和生长特性进行分析。结果表明,在人工培育条件下,仔、稚、幼鱼的摄食率达９７．９％,摄食量占体重的１．４－２３．４％,日摄食量占体重的３６．４７－６５．１９％;摄食具明显的昼夜节律,黄昏和早晨为摄食高峰;对较大个体的饵料生物有明显的选择性;饵料密度对摄食量有一定影响。摄食量与体重的关系式     

罗氏沼虾育苗用水中Mg2+与Ca2+含量及Mg2+/Ca2+对出苗率的影响

１９９１年３－６月和１９９２年３－６月在南汇县东海水产养殖公司对罗氏沼虾育苗用水调配原则与不同基础水的调配方法进行试验研究。结果表明，育苗用水中Ｍｇ＾２＋与Ｃａ＾２＋含量及Ｍｇ＾２＋／Ｃａ＾２＋必须达到一定的范围，这是调配的基本原则。以鱼塘水作基础水时，需添加６种化学药品，其中Ｍｇ＾２＋与Ｃａ＾２＋含量可适范围分别为３００．０－４４０．０ｍｇ／Ｌ与１７０．０－２４４．０ｍｇ／Ｌ，Ｍｇ＾２＋／Ｃａ＾     

鲢鱼幼鱼对盐、碱耐受性的研究

利用盐碱地区氯化物型地下水进行了鲢鱼幼鱼（Ｌ＝５．４～８．２ｃｍ）对盐度（ｐＨ＝８．６０±０．１８）、碱度（ｐＨ＝８．７４±０．３４）及盐碱混合的急性毒性试验。研究结果表明：鲢鱼幼鱼对盐度的２４、４８、７２和９６ｈ的半致死浓度（ＬＣ５０）分别为：１１．２,９．０,８．６和８．２ｇ·Ｌ－１;对碱度的相应ＬＣ５０值分别为５１．４、２７．１、２３．７和１５．７ｍｍｏｌ·Ｌ－１。盐碱混合的正交试验表明盐度和碱度在致毒过程中作用显著;２４ｈＬＣ５０碱度（Ａｌｋ,ｍｍｏｌ·Ｌ－１）及盐度（Ｓ,ｇ·Ｌ－１）的关系为：Ａｌｋ＝３４．１７－１．７８Ｓ。     

磁化水在栉孔扇贝人工育苗上的应用研究

本实验以栉孔扇贝为材料，对栉孔扇贝亲贝、幼虫，进行０．０５～０．９Ｔ不同磁场强度的磁化水培育试验．实验结果表明：磁化水对亲贝蓄养有明显促进性腺发育成熟的作用；磁化水组性腺指数比对照组提高３．５×１０－２．孵化率也大大提高，比对照组提高１６×１０－２．对扇贝幼虫生长发育的影响，在０．３～０．７Ｔ的磁化水范围内，幼虫生长较快，成活率最高，其中０．６Ｔ最好。然后又进行０．６Ｔ生产性应用试验，通过３ａ应用，磁化水组比对照组幼虫成活率可提高１８×１０－２，附着变态率比对照组提高２７×１０－２，单位水体出苗量比对照组提高５０×１０－２左右。另外，磁化水也有明显改善育苗木质的作用，从而保证了扇贝育苗稳产高产。     

日粮水平对黑鲷幼鱼氮收支的影响

于１９９４年８－１１月进行４次黑鲷幼鱼摄食－生长实验,平均水温２６．８,２４．４,２０．１和１４．８℃,生次实验分４个日粮水平,分别对单位体重日摄取、粪便氮、氮排泄和氮生长进行测定和估计。     

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.     

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.     

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.     

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.