Antialgal and Antilarval Activities of Bioactive Compounds Extracted from the Marine Dinoflagellate Amphidinium carterae

With the global ban on the application of organotin-based marine coatings by the International Maritime Organization, the development of environmentally friendly, low-toxic and nontoxic antifouling compounds for marine industries has become an urgent need. Marine microorganisms have been considered as a potential source of natural antifoulants. In this study, the antifouling potential of marine dinoflagellate Amphidinium carterae, the toxic and red-tide microalgae, was investigated. We performed a series of operations to extract the bioactive substances from Amphidinium carterae and tested their antialgal and antilarval activities. The crude extract of Amphidinium carterae showed significant antialgal activity and the EC50 value against Skeletonema costatum was 55.4 μg m L~(-1). After purification, the isolated bioactive substances(the organic extract C) exhibited much higher antialgal and antilarval activities with EC50 of 12.9 μg m L~(-1) against Skeletonema costatum and LC50 of 15.1 μg m L~(-1) against Amphibalanus amphitrite larvae. Subsequently, IR, Q-TOFMS, and GC-MS were utilized for the structural elucidation of the bioactive compounds, and a series of unsaturated and saturated 16- to 22-carbon fatty acids were detected. The data suggested the bioactive compounds isolated from Amphidinium carterae exhibited a significant inhibiting effect against the diatom Skeletonema costatum and Amphibalanus amphitrite larvae, and could be substitutes for persistent, toxic antifouling compounds.     

荧光分光光度法测定海洋贝类体总石油烃的方法研究

研究和建立了一种测定海洋贝类体中总石油烃的改进方法 ,即控温强碱直接皂化、乙醚萃取、正己烷溶解、荧光分光光度仪测定法。该方法的最低检测限为 0 .1 2 mg/kg(大港原油当量 ) ,变异系数( CV) 3 .2 %～ 4 .6% ,相对误差 ( RE) -4 .0 %～ 1 .8% ,具有简便、快速、准确、灵敏度高和费用低廉等特点。     

海洋渔业全要素生产率的变动轨迹及其收敛性分析

基于中国11个沿海省市区1990-2014年海洋渔业投入和产出数据,先运用Malmquist指数法计算了沿海省市区整体以及各个沿海省市区的海洋渔业全要素生产率及其各个分解指数,再运用σ收敛法检验了海洋渔业全要素生产率在考察期间的敛散性。结果表明:海洋渔业全要素生产率对中国海水产品产量的增长起到了很大的推动作用,规模效率指数超过了纯技术效率指数,海洋渔业全要素生产率的地区差异未呈现持续收敛的格局。     

辽宁海洋国土资源开发与海洋经济可持续发展

海洋是人类生存环境的重要组成部分,被人们誉为生命的摇篮、资源的宝库,是全球生命支持系统的组成部分,与人类的生存、发展有着极为密切的关系.海洋可为我国国民经济实现持续、快速、健康的发展提供巨大的资源潜力.目前,我国的经济发展正处在工业化的高速起步时期,但同其他国家相比,面临着人口众多、人均资源量贫乏等严重问题,而海洋可为上述问题提供一条重要的解决途径.     

基于海洋产业结构理论的海域资源配置分析

基于海洋产业结构理论,总结了我国海洋产业结构的发展趋向,分析了海域资源配置与海洋产业结构的关联,以及海洋产业结构对海域资源配置的影响。研究表明,我国海洋产业结构相对协调,但海洋传统产业占海洋产业的比重较高。在海域资源配置的过程中,应在发挥传统海洋产业优势的同时,积极引导新兴海洋产业的发展。     

长岛北四岛海洋牧场海域环境适宜性分析

对长岛北四岛海洋牧场海域101个表层沉积物和102个表层海水样进行取样调查,开展表层沉积物类型、粒度、表层沉积物和海水重金属等指标分析测试,采用单因子污染指数法、富集系数法和潜在生态危害指数法评价该区表层沉积物潜在生态风险,采用海水水质分类和单因子污染指数法评价表层海水污染情况。表层沉积物结果表明：沉积物为泥质砂质砾、砾质泥质砂、砾质泥、含砾泥质砂、砂、粉砂质砂和砂质粉砂,平均粒径介于2.44~5.44Ф;Hg、Cu、Zn、Pb、Cd、As、Cr、硫化物和石油类都符合第一类标准,属于清洁沉积物;Cr、Cu、Pb、Zn、Cd、Hg和As富集系数均＜1,处于低度污染水平;Cr、Cu、Pb、Zn、Cd、Hg和As单项潜在生态危害系数Eir介于0.56~30.71之间,RI均值为66.27,远低于低度生态危害的划分标准值。表层海水结果表明：21个站位受到Hg污染,略高于第一类标准,满足第二类标准,主要位于研究区西北部、西中部和东北部海域,其余指标均符合规定第一类标准;Hg、Cu和Zn含量处于较清洁环境范围内,As、COD、石油类、Pb、Cr和Cd含量处于自然本底环境。根据海底沉积物和海水分析结果得出,长岛北四岛海域海洋牧场规划区底质和水质环境适宜建设海洋牧场。     

Cyclic Shearing Deformation Behavior of Saturated Clays

The apparatus for static and dynamic universal triaxial and torsional shear soil testing is employed to perform stress-controlled cyclic single-direction torsional shear tests and two-direction coupled shear tests under unconsolidated-undrained conditions. Through a series of tests on saturated clay, the effects of initial shear stress and stress reversal on the clay’s strain-stress behavior are examined, and the behavior of pore water pressure is studied. The experimental results indicate that the patterns of stress-strain relations are distinctly influenced by the initial shear stress in the cyclic single-direction shear tests. When the initial shear stress is large and no stress reversal occurs, the predominant deformation behavior is characterized by an accumulative effect. When the initial shear stress is zero and symmetrical cyclic stress occurs, the predominant deformation behavior is characterized by a cyclic effect. The pore water pressure fluctuates around the confining pressure with the increase of cycle number. It seems that the fluctuating amplitude increases with the increase of the cyclic stress. But a buildup of pore water pressure does not occur. The de- formations of clay samples under the complex initial and the cyclic coupled stress conditions include the normal deviatoric deforma- tion and horizontal shear deformation, the average deformation and cyclic deformation. A general strain failure criterion taking into account these deformations is recommended and is proved more stable and suitable compared to the strain failure criteria currently used.     

从海洋生物多样性保护看我国海洋管理体制之完善

我国海洋管理体制存在着中立综合协调部门缺位、政府职责不明确、海洋保护与经济发展割裂、协调机制缺乏、对管理机构不履行法定职责的责任追究机制缺乏、公众参与无法体现等缺陷,要完善我国海洋管理体制,必须确立中立综合协调部门的地位,明确政府职责,融合海洋保护和经济发展,建立相应的行政协助制度和追究机制,落实公众参与等完善措施,实现海洋生物多样性保护。     

我国海洋遥感应用的进展

本文就我国20余年的海洋遥感应用历程,以三个阶段,4种类型信息源的分析及其相关手段和理论基础,按时间前后,着重阐述了所取得的成果,并展示我国海洋遥感技术未来发展的机遇与挑战.     

A Minireview of Marine Algal Virus-Coccolithoviruses

Coccolithophorid is unicellular marine microalgae with a global distribution in temperate and sub-temperate oceanic regions and has the ability to produce ‘the coccoliths'. It is considered to be the second most productive calcifying organism on earth and becoming an important factor in the global carbonate cycle. Emiliania huxleyi is one of the only two bloom-forming coccolithophores and becomes a species crucial to the study of global biogeochemical cycles and climate modeling. Coccolithoviruse is a recently discovered group of viruses infecting the marine coccolithophorid E. huxleyi. They are a major cause of coccolithophore bloom termination, and DMSP concentration is increasing in the process of viral lysis. Phylogenetic evidences support that some genes are functional both in E. huxleyi and its virus(Eh V). Horizontal gene transfer(HGT) of multiple functionally coupled enzymes occurs in E. huxleyi and its DNA virus Eh V has been confirmed, which contributes to the diversification and adaptation of plankton in the oceans and also critically regulates virus-host infection by allowing viruses to control host metabolic pathways for their replication. Therefore, it is of particular interest to understand this host-virus interaction. On this issue, we have made a minireview of coccolithoviruses focusing on the basic characteristics, phylogenesis, horizontal gene transfer and the interaction between the host and its viruses, as well as its important role in global biogeochemical cycling.     

论我国海洋牧场建设的文化逻辑

海洋牧场建设如今已成为海洋经济新的增长点与重要战略。从文化逻辑来看,海洋牧场在我国的推广和建设首先缘于中国近海渔业资源的日渐枯竭,契合了二战后全球兴起的生态整体主义文化思潮,另一方面又顺应中国传统"以海为田"的农业型海洋观,二者合力推动海洋牧场成为我国传统渔业转型升级的新思路。     

京族海洋文化遗产保护

京族是我国的海洋民族,海洋文化遗产形态丰富,具有处环北部湾区的文化特质。京族海洋文化遗产正得到从政府到民间的保护,京族地区可以率先设立“海洋文化遗产日”,塑造海洋文化品牌,构建海洋文化交流媒介,把海洋文化保护工作推向更高的阶段。     

环境信息学在循环经济系统中的应用

本文分析循环经济模式的物质循环和信息流的特点,尤其是循环经济活动对环境的作用以及在信息流方面的表现,讨论正在发展中的环境信息学理论与方法及其发展趋势,在此基础上,具体分析面向循环经济系统的环境信息学的特点,可能发挥的作用以及环境信息学在循环经济模式下如何开展研究和需要重点关注的问题。     

海洋渔业资源时空动态研究

本文结合海洋渔业的应用 ,基于 GIS理论、方法重点探讨了 GIS在海洋渔业中的时空动态、模糊性和不确定性以及社会经济文化等方面问题 :(1)针对海洋渔业时空动态 ,利用面向对象技术构造了适合于多维时空数据存储、计算、分析的概念模型--基于特征的时空层次模型 ,并设计了在现有数据库系统中实现的路线 ,从而构建了基于 client/server结构的海洋渔业数据仓库平台。在构建的数据仓库平台上 ,从11年的 40多万个数据中寻找东海渔场的分布模式及其与非生物环境的关系 ,对东海鱼类资源在空间、时间上的变化进行了深入的分析 :1分析表明 ,东海区渔场分布呈团状和条带状不均匀分布。     

Purification and Characterization of 2-Haloacid Dehalogenasefrom Marine Bacterium Paracoccus sp. DEH99, Isolatedfrom Marine Sponge Hymeniacidonperlevis

2-haloacid dehalogenases constitute a group of dehalogenases which are capable of dehalogenating the halogenatedorganic compounds. So far, the 2-haloacid dehalogenases have been found in many bacteria, but not in Paracoccus genus. In thepresent study, one enzyme 2-haloacid dehalogenase （designated as Deh99）, induced by DL-2-chloropropionate （DL-2-CPA）, waspurified from the marine bacterium Paracoccus sp. DEH99, isolated from marine sponge Hymeniacidon perlevis. The enzyme ofDeh99 was purified to homogeneity by ammonium sulfate precipitation, ion exchange chromatography （Q-Sepharose HP）, and Su-perdex 200 gel filtration chromatography. The molecular weight of Deh99 was estimated to be 25.0 kDa by sodium dodecyl sul-fate-polyacrylamide gel electrophoresis （SDS-PAGE）, and 50.0 kDa natively by gel filtration chromatography. The enzyme of Deh99stereospecifically dehalogenated L-2-CPA to produce D-lactate, with an apparent Michaelis-Menten constant （Kin） value of0（21 mmolL-1 for L-2-CPA. The optimal pH and temperature for Deh99 activity were 10.0 and 40°C, respectively. The enzyme ofDeh99 acted on short-carbon-chain 2-haloacids, with the highest activity towards monochloroacetate. The activity of Deh99 wasslightly affected by DTT and EDTA, but strongly inhibited by Cu2＋ and Zn2＋. The enzyme of Deh99 shows unique substrate specific-ity and inhibitor sensitivities compared to previously characterized 2-haloacid dehalogenases and is the reported one about purified 2-haloacid dehalogenase isolated from the bacteria of Paracoccus genus.     

海上拖缆随机采样抗混叠机理分析

目前海上拖缆地震采集只有道间距满足采样条件,而炮间距、炮线距和缆间距都不能满足采样条件,造成了地震数据的采样不足,导致频谱产生混叠效应。近年来发展了海上拖缆随机采集技术,为了分析该采集技术抗假频特性,以简谐信号和合成地震记录为研究对象,在空间规则采样的条件下,分别分析了充足采样和不充足采样情况下的频谱特征,分析了空间假频产生的原因。同时,在规则采样分析的基础上,对简谐信号和合成地震记录进行了随机抽样和频谱分析,研究了随机采样对空间假频的压制作用,数据分析结果表明海上拖缆地震随机采样可以降低频谱的混叠效应。      

A Review of Microplastics in China Marine Waters

Microplastics(<5 mm) are ubiquitous in the environment and can pose potential danger to the ecosystem and even human health. As the sink of microplastics, the ocean, especially the densely populated coastal area, has become a hotspot for research on microplastic pollution. In the last decade, the research of marine microplastics has been rapidly increasing in China. This review summarized the microplastic research conducted in China marine waters so far, and introduced the trends and progress...     

Cyclic load testing of pre-stressed rock anchors for slope stabilization

The objective of this research was to assess the characteristics of seismic induced damage and the deformation patterns of pre-stressed cement-grouted cables that are used for rock slope stabilization projects subjected to quasi-static cyclic loading. The experimental configuration includes the installation of 15 pre-stressed cables in a slope model made of concrete blocks (theoretically rigid rock mass) on top of a pre-existing sliding surface. The study showed that: (i) The pre-stressed cables exhibited great seismic performance. Rapid displacement of the model blocks was observed after the complete loss of the initial pre-stress load under continued applied cyclic loads and exceedance of the state of equilibrium, which implies the higher the initial pre-stress load, the better the seismic performance of the rock anchor; (ii) The failure of the pre-stressed cables was due to fracture at the connection of the tendons and cable heads under cyclic loading. The sequence of failure had a distinct pattern. Failure was first observed at the upper row of cables, which experienced the most severe damage, including the ejection of cable heads. No evidence of de-bonding was observed during the cyclic loading; (iii) The stress distribution of the bond length for pre-stressed cables was highly non-uniform. High stress concentrations were observed at both the fixed end and the free end of the bond length both before and immediately after the state of equilibrium is exceeded. The results obtained can be used to evaluate the overall performance of pre-stressed rock anchors subject to seismic loading and their potential as rockfall prevention and stabilization measures.