杭州湾海水密度研究

用磁力浮沉子密度测量装置,在１５ ～２５ ℃之间的三个温度下测定了杭州湾３０ 个水样的密度。结果表明,测定值皆高于相应条件下国际标准海水状态方程的计算值,在海水盐度范围５．５６～２６ ．４ ,密度平均偏差值为２８ ．２ ～１２０ ．５ ×１０－ ３ｋｇ／ｍ３ 。测定密度和计算密度的偏差随盐度的降低而增大,与盐度的变化成直线相关;与（Ｃａ２ ＋ ）／Ｓ和比碱度之间皆呈指数曲线相关。杭州湾海水枯水期和丰水期水样的（Ｃａ２ ＋ ）／Ｃｌ 比平均值分别超出大洋水平均值２８ ．８％ 和２０ ．６％ ;杭州湾海水枯水期和丰水期的比碱度平均值分别超出大洋水平均值６０ ．３ ％ 和３０２ ％ ;（Ｍｇ２ ＋ ）／Ｃｌ 比、枯水期水样ＳＯ２ －４ ／Ｃｌ 比及Ｓｒ２ ＋ ／Ｃｌ 比与大洋水平均值相同或相近,丰水期水样ＳＯ２ －４ ／Ｃｌ 高出大洋水平均值７ ．１ ％ ;结合主要离子在湾内平面分布图,得出杭州湾海水高的Ｃａ２ ＋ ／Ｃｌ 比、比碱度和ＳＯ２ －４ ／Ｃｌ 比,除了受江水输入影响以外,主要还是受湾北岸工业区废水排放的影响。并首次给出了杭州湾海水的密度公式。     

长江三角洲地区晚第四纪古土壤地球化学特征

首次研究长江三角洲地区晚第四纪古土壤的地球化学特征。本区第一“暗绿色硬粘土层”的硅铝率在２．８０～３．３７之间,说明该层已经发生了较强的土壤化作用,可以确定为古土壤。古土壤层土体样品与胶体样品的化学全量分析结果之间有很大的差异,只能用胶体样品来研究古土壤特征。在古土壤中,ＳｉＯ２、Ａｌ２Ｏ３、ＭｇＯ、ＴｉＯ２、Ｋ２Ｏ相对积聚,而Ｆｅ２Ｏ３、ＣａＯ、ＭｎＯ、Ｎａ２Ｏ、Ｐ２Ｏ５相对淋溶。在剖面上,ＳｉＯ２／（ＭｇＯ＋ＣａＯ）的分子比值变化规律表明气候逐渐湿润     

掺Eu~(2+)的卤磷酸盐的发光特性和内部能量传递

探讨Ｂａ２＋离子搀杂对（Ｃａ０．５Ｓｒ０．５）５（ＰＯ４）３Ｃｌ：Ｅｕ２＋和（Ｃａ０．４Ｓｒ０．６）５（ＰＯ４）３Ｃｌ：Ｅｕ２＋量子发光效率的影响。当用Ｂａ２＋离子代替Ｃａ２＋或Ｓｒ２＋离子进入晶体时，Ｅｕ２＋离子的发光特性发生改变：发射峰的峰值降低，热猝灭的温度升高。并采用位型坐标理论给予解释。根据晶体的结构特征，对占据两个不等当晶体学位置的Ｅｕ２＋离子发光中心之间的能量传递进行了探讨     

珠江口表层水中主要常量离子的研究

９９４年９月采集了珠江口表层海水水样,并对其溶解态的Ｋ＋、Ｎａ＋、Ｃａ２＋、Ｍｇ２＋、ＳＯ２－４、Ｃｌ等化学要素进行了测定。结果表明,珠江口调查海域表层水中溶解态的Ｋ＋、Ｎａ＋、Ｃａ２＋、Ｍｇ２＋、ＳＯ２－４主要受陆源淡水与外海水物理混合稀释的影响,与Ｃｌ具有良好的直线正相关;Ｃａ２＋／Ｃｌ、ＳＯ２－４／Ｃｌ明显高于大洋水相应比值,Ｎａ＋／Ｃｌ、Ｍｇ２＋／Ｃｌ略高,而Ｋ＋／Ｃｌ比大洋比值低;在与中国其它各主要河口表层水对应Ｃｌ比较中,珠江口的ＳＯ２－４／Ｃｌ较高,而Ｃａ２＋／Ｃｌ,Ｍｇ２＋／Ｃｌ比值居低;上述各主要常量离子和Ｃｌ的等值线均沿自北向南走向递增。     

改性膨润土对赤潮落种及海水中DRP,COD的去除效应

实验室研究了不同条件制备的改性膨润土对赤潮生物及海水中ＤＲＰ,ＣＯＤ的去除效应,结果表明,改性膨润土有效Ａｌ为１．５％时去除效应最好,经Ｎａ２ＳＯ４,Ａｌ２（ＳＯ４）３改性的膨润土在ｐＨ＝５．５时去除效应最佳,改性膨润土的去除效率随Ａｌ／ＳＯ４比值增加而增加,改性膨润土添加絮凝剂醋甲壳质和Ｃａ（ＯＨ）２提高了去除功效。     

Ca2+对罗非鱼嗅电图的影响

将４种不同浓度的Ｃａ＾２＋溶液灌注罗非鱼嗅上皮,观测其对罗非鱼嗅电图（ｅｌｅｃｔｒｏｏｌｔａｃｔｏｇｒａｍ,简称ＥＯＧ）电位幅值的影响,结果表明：Ｃａ＾２＋对罗非鱼ＥＯＧ具双重效应,在一定浓度范围（１～４ｍｍｏｌ／ｄｍ＾３）内,随着Ｃａ＾２＋对ＥＯＧ的效应由抑制逐渐转向促进,表现为反应的增大与Ｃａ＾２＋浓度的提高呈正相关。但当Ｃａ＾２＋浓度进一步提高到８ｍｍｏｌ／ｄｍ＾３时,ＥＯＧ反映减小,呈现抑制效应,本文探讨了Ｃａ＾２＋影响ＥＯＧ的可能机制。     

台湾海峡西部海域水体中的二氧化碳体系

据１９８４年５月至１９８５年２月的调查资料，计算了该水体中二氧化碳体系各要素的统计值，着重研究了它们的季节变化及其与水文，化学和生物因子的关系。结果表明该水体中ＰＣＯ２，ＣＯ２（Ｔ），ＣＯ＾２＾－３，ＨＣＯ３，∑ＣＯ２，ＣＯ＾２＾－３／∑ＣＯ２，ＨＣＯ３／∑ＣＯ２，ＨＣＯ２，ＣＯ２（Ｔ），ＣＯ＾２＾－３，∑ＣＯ２／Ｃｌ，Ωｃ，Ωａ和Ｃ：Ｎ：Ｐ平均值依次分别为２５１ｄＰａ，８．４３μｍｏｌ／ｄｍ×３     

冲绳海槽晚更新世以来环境演变的矿物-地球化学记录

国家自然科学基金资助项目（Ｎｏ．４９６７６２９０,１９９７～１９９９）“冲绳海槽晚更新世以来环境演变的矿物 地球化学记录” ,根据表层和柱状样品的成因矿物学和地球化学研究 ,重建了冲绳海槽中部自晚更新世以来的环境演变历史。沉积物的ＴｉＯ２ （ＴＦｅ２Ｏ３ ＭｇＯ）,Ｋ２Ｏ／Ｎａ２Ｏ （ＴＦｅ２Ｏ３ （ＴＦｅ２Ｏ３ ＭｇＯ）,Ａｌ／（Ａｌ Ｍｎ Ｆｅ）,Ｌａ／Ｙｂ ＲＥＥ,ＬＲＥＥ／ＨＲＥＥ（平均８．６９） ,δＥｕ（平均０．６０）和轻稀土型配分类型特征判明为活动大陆边缘 大陆岛弧型沉积环境 ,沉积物具有典型…     

九龙江口生物可利用磷的行为与人海通量

于１９９５年３、５月在九江口进行两个航次的现场调查,研究不同形态磷的河口行为,并估算生物可利用磷的入海通量。结果表明,在Ｓ〈２０区域内,溶解活性磷（ＤＲＰ）的行为受控于“缓冲机制”,其含量在８－１０μｇ／ｄｍ＾３水平上下波动。颗粒磷中ＭｇＣｌ２可提取磷（ＭｇＣｌ２－Ｐ）含量随盐度增大而增大,并与叶绿素ａ以及悬浮物Ｆｅ、Ｍｎ、Ａｌ含量呈正相关关系。ＮａＯＨ／ＮａＣｌ可提取磷（ＮａＯＨ／ＮａＣｌ－Ｐ）     

珠江口海水密度的研究

用磁力浮沉子密度测量装置,在１５ ～２５ ℃之间的三个温度下测定了珠江口２０ 个水样的密度。结果表明,测定值皆高于相应条件下国际标准海水状态方程的计算值,在海水盐度范围０．０８～３３ ．４４６ ,密度平均偏差范围为２ ．４ ～５４．０ ×１０ － ３ｋｇ／ｍ３ 。测定密度和计算密度的偏差随盐度的降低而增大,与盐度的变化成直线相关：与（Ｃａ２ ＋ ）／Ｓ、ＳＯ４２ － ／Ｓ比和比碱度之间皆呈指数曲线相关。珠江口水样（Ｃａ２ ＋ ）／Ｃ１ 、ＳＯ４２ － ／Ｃ１ 和比碱度平均值分别超出大洋水平均值１７ ．８ ％ 、８ ．２１ ％ 和１５２ ％ ,其余的Ｎａ ＋ ／Ｃ１、Ｋ＋ ／Ｃ１ 和Ｓｒ２ ＋ ／Ｃ１ 比值与大洋水无明显差别,基本类同。珠江口海水的高碱度、高（Ｃａ２ ＋ ）／Ｃ１ 和高ＳＯ４２ － ／Ｃ１ 是造成其海水密度正偏差的主要因素。经计算机拟合,首次导出了珠江口海水密度的状态方程,该方程计算值与实验值的平均标准偏差为±２．５×１０－ ３ｋｇ／ｍ３ 。     

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.     

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.     

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。     

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.     

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.     

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.