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4种单胞藻同化速率与温度关系的实验研究 总被引：4，自引：0，他引：4
本文采用~(14)C示踪法,实验研究了温度对小球藻、牟氏角毛藻、聚生角毛藻和钙质角毛藻同化速率的影响,发现这4种藻类的同化速率随温度呈非线性函数变化,并从理论上阐述了藻类生长过程中对温度的要求和适应,以及这4种藻类光合过程的平均活化能。 相似文献
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于2006年5-11月对东海泉州湾赤潮监控区四个监测站位开展赤潮常规监测。根据监测结果,分别以各站位23项水质理化生物环境因子指标为自变量,相应赤潮藻类优势种的细胞密度为因变量,进行多元逐步回归分析,建立了各站位优势种中肋骨条藻(Skeletonema costatum)、太平洋海链藻(Thalassiosira pacifica)、微小原甲藻(Prorocentrum minimum)、尖刺拟菱形藻(Pseudo-nitzschia pungens)、丹麦细柱藻(Leptocylindrus danicus)和旋链角毛藻(Chaetoceros curvisetus)等的细胞密度多参量回归方程。结果表明,所有回归方程的复相关系数都接近于1,方差分析的结果均为回归极显著,表明所建立的回归方程可作为相应赤潮优势种细胞密度预报方程的高度有效性,将对今后泉州湾的赤潮预报提供良好的指导作用。 相似文献
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于2006年5—11月对东海泉州湾赤潮监控区设定4个采样站位,进行赤潮常规监测。结果表明,泉州湾藻类优势种由中肋骨条藻(Skeletonema costatum)、太平洋海链藻(Thalassiosira pacifica)、微小原甲藻(Prorocentrum minimum)、尖刺拟菱形藻(Pseudo-nitzschia pungens)、丹麦细柱藻(Leptocylindrus danicus)及旋链角毛藻(Chaetoceros curvisetus)等赤潮生物组成,虽然中肋骨条藻为最主要的优势种,但有3个站位出现了上述优势种的演替。通过深入分析该海域水质营养盐含量及组成结构的动态变化对赤潮藻类优势种演替的影响,发现由于不同的赤潮藻类种群具有各自的生态习性及适应环境的生长增殖策略,海域水质营养盐含量和组成结构的变化,会引起赤潮藻类种群增殖竞争力间强弱的相对变化,而种群增殖竞争力强的种类有可能迅速增殖取代原有的优势种而演替为新的优势种,这是一个动态的过程。 相似文献
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收集统计了2008—2017年的福州沿海赤潮记录历史资料,对近十年福州沿海赤潮的基本特征进行综合分析,结果表明:(1)2012年赤潮发生的次数最多,2010年赤潮发生的面积最大。近五年(2013—2017年)与之前五年(2008—2012年)相比,赤潮的年发生次数、持续天数和发生面积都呈明显减少的趋势;(2)赤潮的发生期为3—9月,高发期为5—6月;(3)赤潮主要发生在黄岐半岛沿海、闽江口沿海、长乐沿海、福清湾-海坛海峡海域和罗源湾海域,大部分发生在黄岐半岛沿海。封闭型和半封闭型海域发生的赤潮较多,不同藻类的空间分布存在较明显的区域特征;(4)引发福州沿海赤潮的藻种有8种,分别是东海原甲藻、中肋骨条藻、米氏凯伦藻、夜光藻、柔弱拟菱形藻、圆海链藻、刚毛根管藻和丹麦细柱藻,其中前3者为主要影响种,作为其中唯一的有毒藻种,米氏凯伦藻虽然在发生次数、持续天数和发生面积上占比均不大,但是近十年福州沿海几乎所有由赤潮灾害导致的重大渔业经济损失均与其有关。 相似文献
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鲜藻类饵料在传统上一直是对虾幼体培养中所需要的营养源。在对虾育苗场广泛使用的藻类品种有:骨条藻(Skeletonema costatum)、角毛藻(Chaetoceros calcitrans)和扁藻(Tetraselmis sp.)。而角毛藻是斑节对虾(Penaeus monodon)使用最早的鲜活饵料。从1986～1988年,东南亚渔业发展中心(SEAFDEC)藻类实验室生产的6个品种中,角毛藻占总生产量的34％。同其他5种藻类相比较,角毛藻饵料对斑节对虾的生长和存活率是最高的。 相似文献
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大亚湾澳头海域硅藻、甲藻的数量变动及其与环境因子的关系 总被引：12，自引：1，他引：11
于1997年7月-1998年6月采集大亚湾澳头海域水样,根据《海洋监测规范》分析调查方法,研究了硅藻和甲藻的数量变动及其与环境因子之间的关系,共鉴定出浮游植物198种,其中硅藻98种,甲藻83种。结果表明,大亚湾浮游植物细胞密度较高,年平均细胞密度为424．7cells／ml,最高细胞密度为6689．8cells／ml,硅藻为浮游植物的主要类群。调查期间共发生藻类水华7次,硅藻可在全年各季节发生水华,而甲藻水华仅在春季发生。硅藻水华的消退与N的大量消耗有关,而甲藻水华对P消耗较大。结果表明,大亚湾合适的温度、盐度、气象条件、丰富的硅酸盐含量及N、P等营养盐的及时补充是大亚湾浮游植物数量高和水华频繁发生的主要原因,同时风、流等物理因素对藻类的聚积作用对水华的发生也有一定的促进作用。 相似文献
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据2007年春季在南海西北部陆架区海域进行的网采浮游植物调查数据,分析了浮游植物群落的结构特征．此次共鉴定出浮游植物4门318种,其中硅藻类183种,甲藻类128种,蓝藻类5种,金藻类2种．大部分海域浮游植物种类数在40～70种之间,外海区域的种类数稍高于沿岸．浮游植物密度的变化范围为0．22×10。～3683．85×10。eells／m’,平均值（标准偏差）为97．49×10。（±437．38×10。）cel｜s／m。．其高值区主要位于粤西近岸海域,向外海呈递减趋势．调查海域硅藻类的平均密度（标准偏差）最高,为93．82×10。（±434．34×10。）cells／m’;甲藻类的次之,为3．65×10。（±9．08×10。）cells／m’．浮游植物优势种主要有拟旋链角毛藻（Chaetocerospseudocurvisetus）、细弱海链藻（Thalassiosirasubtilis）、中肋骨条藻（Skeletonemacostatum）、劳氏角毛藻（Chaetocerosloren—zianus）和菱形海线藻（Thalassionemanitzschioides）．该调查海域浮游植物多样性指数的变化范围为1．48～6．23,平均值（标准偏差）为4．70（±1．03）,其分布趋势与浮游植物密度的分布趋势大致相反．将站位依等深线划分为粤西近岸海区、琼东南近岸海区和外海海区,应用非度量多维标度（nMDS）和聚类分析法分析这3个海区的浮游植物群落结构差异,并通过ANOSIM和SIMPER进行检验．结果表明3个海区之间浮游植物群落结构具有显著性差异,且粤西近岸海区与外海海区之间差异性较高．近岸种拟旋链角毛藻和中肋骨条藻在粤西近岸海区为最主要的优势种,而外海海区优势种较多,且大部分为大洋暖水性种类． 相似文献
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Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
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. 相似文献
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G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
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. 相似文献
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Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
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. 相似文献
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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。 相似文献
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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. 相似文献
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Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
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. 相似文献
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《海洋学报(英文版)》2014,(11):161-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献