三唑磷对四种水生生物的毒性及安全评价研究

本文研究了三唑磷对小球藻、卤虫、南美白对虾、泥蚶四种水生生物的急性毒性作用，结果显示，三唑磷对小球藻的48h的EC50为24μg/dm^3,72h的EC50为15μg/km^3；对卤虫的24hLC50为1．64mg／dm^3，48hLC50为0．8mg／dm^3；对南美白对虾仔虾的48hLG0为3．2μg／dm^3，96hLC50为1．1μg/dm^3。；对泥蚶的48hLC50为21．0mg／dm^3，96hLC50为10．2mg／dm^3。三唑磷对小球藻、卤虫、南美白对虾为高毒农药，泥蚶对三唑磷有很强的耐受力。     

秦皇岛海域“褐潮”海水对卤虫、轮虫存活和摄食的影响研究

为评价秦皇岛褐潮现场海水的毒性,作者利用HPLC技术及CHEMTAX,分析了2013年7月2日采自秦皇岛褐潮高峰期微型及微微型浮游植物的色素组成及群落结构;测定了卤虫(Artemia salina)、轮虫(Brachionus plicatilis)存活率和摄食量。研究表明,褐潮海水微型及微微型浮游植物中,海金藻(Pelagophyceae)占主要优势,其生物量占总生物量的72.6%。褐潮海水抑制卤虫存活,卤虫48 h存活率降至77%;对轮虫24 h存活没有显著效应。此外,褐潮海水抑制卤虫、轮虫的摄食,卤虫、轮虫8 h内摄食量分别由(5.5±0.4)ng/个降至(2.4±0.4)ng/个、由(1.5±0.2)ng/个下降至(0.9±0.1)ng/个。该结果与美国的3株褐潮藻的毒性进行了比较。CCMP 1507对卤虫存活有显著抑制作用,其他两株没有显著效应;3株褐潮藻对轮虫24 h存活都没有显著影响。暴露于3株褐潮藻中,卤虫的摄食量均显著较低;其中CCMP 1507在混合饵料中还抑制卤虫、轮虫对其他藻的摄食。对CCMP 1507各组分分析发现,该藻的毒性主要来源于藻细胞。结合现场试验与室内试验结果分析表明,秦皇岛褐潮对卤虫、轮虫有一定的毒性,其毒性与CCMP 1507的毒性相当。     

人工培育脊尾白虾蚤状幼体的饵料基础研究

通过脊尾白虾蚤状幼体饵料种类、饵料组合和食物密度的比较试验 ,研究了脊尾白虾育苗的适宜开口饵料和育苗期饵料组合 ,测定了不同时期蚤状幼体的捕食率及其日粮。结果表明 :饵料种类对脊尾白虾蚤状幼体 期 (Z1)至 期 (Z2 )的变态率和变态所需时间没有明显影响 ,Z1可以不投饵 ,但适量投喂单胞藻或轮虫 ,能明显提高 Z2 活力和 Z2 至 Z3 的变态率。人工培育脊尾白虾蚤状幼体的适宜饵料是卤虫无节幼体 ,在幼体培育前期 (Z1)投喂单胞藻、轮虫 ,后期 (Z3 以后 )添加鱼糜效果也很好。蚤状幼体对卤虫无节幼体的捕食率和日粮随幼体发育而明显增加 ,同一发育时期则随饵料密度的增大而增加 ,但达到一定密度后 ,捕食率增幅明显下降。根据幼体日粮难以确定育苗期间卤虫无节幼体的最佳投喂方案     

几种饵料浮游动物脂肪酸组成分析及营养效果评价

本文采用气相色谱分析法对海水鱼类育苗常用的4种饵料浮游动物的脂肪酸组成和含量进行了测定分析.结果表明卤虫无节幼虫、皱褶臂尾轮虫、蒙古裸腹溞和太平洋纺锤水蚤的粗脂肪含量分别占其体重的21.54％、9.70％、6.67％和4.66％.单不饱和脂肪酸的含量排序分别为蒙古裸腹溞＞纺锤水蚤＞轮虫＞卤虫；多不饱和脂肪酸含量则为卤虫＞裸腹溞＞轮虫＞纺锤水蚤.此外，太平洋纺锤水蚤尚含有C226(DHA)高不饱和脂肪酸，这在其它饵料生物中并未检出.卤虫无节幼虫和褶皱臂尾轮虫的脂肪酸组成中，油酸(C181)、亚油酸(C182)和亚麻酸(C183)占有较大比例，而二十碳以上的不饱和脂肪酸含量很低.文中讨论了脂肪酸组成和含量与营养效果的关系.     

三种重金属离子对卤虫的急性毒性研究（英文）

以卤虫无节幼体(36h)和成虫(16d)为例,在温度为15±3℃、盐度为30的条件下,通过单因子静态急性毒性试验方法,分别研究了Cu~(2+)、Mn~(2+)和Zn~(2+)对卤虫的无节幼体和成虫的单一毒性效应;在此基础上,以卤虫卤虫无节幼体(36h)为例,在相同试验条件下,通过等毒性溶液法,研究了Cu~(2+)、Mn~(2+)和Zn~(2+)对卤虫的联合毒性效应。试验结果表明:卤虫无节幼体对三种金属离子的耐受能力均高于成虫,Cu~(2+)﹑Mn~(2+)和Zn~(2+)的48h LC_(50)分别是4.0、27.19和115.95 mg/L,而成虫Cu~(2+)﹑Mn~(2+)和Zn~(2+)的48h LC_(50)仅为1.31、6.86和34.23 mg/L;且对两个时期的卤虫,三种金属离子毒性由强至弱均为Cu~(2+) Mn~(2+)Zn~(2+);三种重金属对卤虫无节幼体和成虫的安全浓度(SC)分别是0.4、2.72、11.6、0.13、0.69和3.42 mg/L。联合毒性试验结果表明Cu-Mn、Cu-Zn和Mn-Zn均对卤虫无节幼体表现为拮抗作用。     

饵料影响锯缘青蟹幼体干重及化学元素(C、H、N)含量的实验研究

对喂食不同饵料的锯缘青蟹各期幼体的干重及化学元素(C、H、N)含量进行逐日测定,结果表明:在Ⅱ期,一直喂食轮虫的青蟹幼体,其干重及C、H、N含量与从该期起以卤虫无节幼体替代轮虫喂养的幼体相比较,二者相差不大;但进入Ⅲ后,却明显低于在溞Ⅱ或溞Ⅲ以卤虫无节幼体替代轮虫喂养的幼体;且差距随幼体发育不断地增大,至变态为大眼幼体时,其干重及C、H、N含量仅为在溞Ⅱ或溞Ⅲ起改喂卤虫的60%～70%.虽然不同喂食条件的青蟹幼体其C、H、N绝对含量相差很大,但其各自占干重的百分比却相对稳定,一直喂食轮虫的幼体只稍低。元素比与喂食条件无明显关系。青蟹溞状幼体各发育期间的生长呈指数式,期内生长呈幂函数式。大眼幼体期内的生长亦呈幂函数式。     

人工培育脊尾白虾蚤状幼体的饵料基础研究

通过脊尾白虾蚤状幼体饵料种类，饵料组合和食物密度的比较试验，研究了脊尾白虾育苗的适宜开口饵料和育苗期饵料组合，测定了不同时期蚤状幼体的捕食率及其日粮。结果表明：饵料种类对脊尾白虾蚤状幼体Ⅰ期（Z1)至Ⅱ期（Z2）的变态率和变态所需时间没有明显影响，Z1可以不投饵，但适量投喂单胞藻或轮虫，能明显提高Z2活力和Z2至Z3的变态率。人工培育脊尾白虾蚤状幼体的适宜饵料是卤虫无节幼体，在幼体培育前期（Z1）投喂单胞藻，轮虫，后期（Z3以后）添加鱼糜效果也很好。蚤状幼体对卤虫无节幼体的捕食率和日粮随幼体发育而明显增加，同一发育时期则随饵料密度的增大而增加，但达到一定密度后，捕食率增幅明显下降。根据幼体日粮难以确定育苗期间卤虫无节幼体的最佳投喂方案。     

三唑磷对泥蚶急性毒性及血清SOD,CAT酶活性的影响

三唑磷对泥蚶(Tegillarca granosa)的48h LC50为21．0mg／L,96h LC50为10．2mg／L,依此设计三唑磷对泥蚶的胁迫质量浓度(1．1,2．2,4．4,22mg／L),分别于胁迫后第0．5,1,2,4,8天及解除胁迫后第4天采样,研究三唑磷胁迫后泥蚶血清超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性的变化情况。结果表明,随三唑磷胁迫浓度和时间的不同,泥蚶血清蛋白质质量浓度无显著性差异;在0.5,1d时各处理组的SOD无显著影响,从第2天起,SOD活性显著下降,48h的LC50为3．62mg／L;CAT的活性在第1天显著升高,而后逐渐降低。三唑磷胁迫下,SOD,CAT活性呈现一定的剂量效应与时间效应。胁迫解除后,蛋白质、SOD和CAT均得到不同程度的恢复,表明泥蚶具有一定的生理调节机能。     

高密度轮虫对点带石斑鱼早期仔鱼培育影响的研究

本试验在水体为1000dm^3、仔鱼密度为15ind．／dm^3条件下，研究不同轮虫密度(10、25、40、70、100ind．／cm^3)对点带石斑鱼早期仔鱼摄食和生长的影响．至仔鱼12日龄的培育试验结果表明，在点带石斑鱼早期仔鱼的培育过程中，投放轮虫对水质有影响，特别是在2～6日龄间，DO值和pH值都有一降低过程，但随后即回升并相对稳定；轮虫密度越高则pH值越低，pH值最低出现在4～6日龄，4日龄时10ind．／cm^3组的pH值比100ind．／cm^3组高0．32．在10～100ind．／cm^3的轮虫密度范围内，较低的轮虫密度对仔鱼的生长有利，12日龄10ind．／cm。组仔鱼的全长比100ind．／cm^3组高31．83％，但100ind．／cm^3组仔鱼的成活率比10ind．／cm^3组的高出近一倍；不同轮虫密度下仔鱼摄食轮虫数量的差异并不明显；但9日龄以后，过高的轮虫密度100ind．／cm^3下仔鱼生长速度显著降低．     

几种卤素类消毒剂对刺参幼参的急性毒性作用

在水温18.5~20℃的静水条件下,用4种卤素类消毒剂对刺参幼参进行了急性毒性试验。结果表明,三氯异氰尿酸(trichloroisocyanuric acid,简称TCCA)对刺参幼参的24 h LC50、48 h LC50和安全质量浓度(Cs)分别为33.22、25.32、4.41 mg/L,二溴海因(dibromo dimethyl hydantoin,简称DBDMH)的24 h LC50、48 h LC50和Cs分别为371.17、339.65、85.32 mg/L,聚维酮碘(povidone-iodine,简称PVP-I)的24 h LC50、48 h LC50和Cs分别为3.14、1.450、.09 mg/L,季铵盐络合碘(quaternary ammonium salt-iodine,简称QASI)的24 h LC50、48 h LC50和Cs分别为4.24、2.02、0.14 mg/L。研究表明,4种消毒剂对幼参的毒性大小依次为聚维酮碘>季铵盐络合碘>三氯异氰尿酸>二溴海因。     

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.     

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.