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深海原生动物多样性研究进展 总被引：2，自引：0，他引：2
<正>1引言原生动物是一大类单细胞真核生物的统称,其中自由生活的主要类群包括异养鞭毛虫、纤毛虫和肉足虫(有孔虫和放射虫为代表);它们是生物圈中数量最为庞大的吞噬营养类群,部分种类具有内共生藻类或功能性叶绿体而进行兼性营养。在水环境中,不论是浮游或是底栖生活的原生动物,其生命过程与水体和底质的环境存在着密切的联系;并且通过各种营养关系与其他生物共同联结成为一个有机整体。同时,原生动物的基础研究也为探索真核生 相似文献
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呼吸速率是动物代谢生理中的一个重要指标。研究生态系统中的能量转移、生物群落的功能和结构、环境对动物生命活动的影响等,都要进行耗氧量的测定。如浮游动物的呼吸速率与天然栖息处迁移的关系,浮游动物中桡足类(Copepoda)的呼吸速率与年龄以及区域和季节变异的关系,哲水溞(Diaptomus)在不同温度时的呼吸作用,原生动物的不同个体大小、重量和耗氧量的关系等等。此外,还有不少学者进行了污染水体中有毒物质对微小水生动物致毒作用的研究,如重金属离子对原生动物半致死浓度的测定,其目的是用它作为指示生物。在污染水体和污水的生物处理过程中,都有原生 相似文献
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胶州湾浮游原生生物时空分布特征——丰度周年变化及与环境因子间的关系 总被引：2，自引：0，他引：2
为了解胶州湾浮游原生生物时空分布特征及与环境因子间的关系,自2007年6月～2008年5月,对青岛胶州湾内5个站点表层水的浮游原生生物丰度及环境因子进行了累计24次的周年采样调查及定性、定量分析.结果显示:(1) 浮游原生生物周年变动具有2个高峰,分别出现在4月和8月;(2) 浮游硅藻、鞭毛藻和纤毛虫的丰度周年变动均为双峰型:春节(4月)高峰、秋节(8月)高峰;(3) 浮游原生生物丰度与叶绿素a和溶解氧呈显著性相关,而其群落结构的变化与盐度、溶解氧、硝态氮和亚硝态氮的组合呈显著性相关.本工作为进一步探讨富营养化的内湾型近岸水体内原生生物生态学结构与功能提供了一份必要的基础资讯. 相似文献
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近些年来，夏季黄海浒苔大规模暴发，并在青岛近岸海域大面积聚集，引起了广泛的关注。本文基于在夏季和冬季所获得的多学科调查资料，重点研究了青岛近海的水文-生物地球化学过程及其生态影响，阐明了该海域物理-化学-生物等多参数之间的耦合响应。研究显示，夏季黄海冷水团的边界可扩展至青岛近岸海域，并在局部涌升至上层水体，形成沿岸上升流；该上升流可对上层营养盐产生一定的补充，进而促进浮游植物的繁殖，并于底层海域对应形成溶解氧（DO）和pH的低值。夏季青岛近海的上升流可能还有利于随南风漂移至此的浒苔的生长，并在一定程度上引起浒苔的局地旺发；同时，夏季该海域特定的锋面系统对浒苔聚集的影响也不容忽视。冬季黄海暖流在苏北浅滩外侧向山东半岛南部海域延伸，扩展至青岛近海的暖水舌与近岸低温水之间的锋面特征明显，而且在向岸暖水与近岸冷水间还对应形成了明显的营养盐和叶绿素（Chl-a）锋面。该项研究从多学科交叉的视角，增进了对青岛近海物理、化学和生物过程之间耦合关系的认识。 相似文献
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作者等曾于1978—1980年在西湖进行过治理前浮游动物的调查研究。从1981年开始,有关部门对污染严重的西湖水体进行了全面的综合治理。其主要措施有:整修湖岸,制止陆地的污物、尘土随雨水流入湖中;截污、环湖埋设近10公里的污水截流管道,使沿湖的生产和生活污水不再排入西湖;疏浚、清除湖底污泥五万立方米,增大蓄水量两倍多;打捞湖面废弃物,平均每天打捞废弃物200余公斤,减少了污物的沉积;改用直流电机游船,代替柴油机动游船,防止油垢污染;引流,从钱塘江引2000万吨清水入湖。由于采取上述治理措施,特别是引流的结果,近年来已逐渐降低了西湖水体的富营养化程度。治理后,西湖浮游动物有何变化,亦是各方关注的一个问题。为此,作者于1984年1—12月再度进行了西湖浮游动物的调查。按钱塘江水流入湖后的水路方向,布设了四个采样点,即小南湖和西里湖点(进水区)、湖中心点(敞水区)和少年宫点(出水区)。 相似文献
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蚌、鱼养殖模式对水体富营养化控制作用的研究 总被引：11，自引：0，他引：11
为了探索控制水体富营养化的新方法．在5～9月长江中下游地区水体富营养的发展期，通过野外规模性试验，即水体吊养珍珠蚌并搭养少量鱼类，然后定期测定4个主要富营养化指标，观察水生生物种群和数量。结果表明，养蚌育珠并搭养适量鱼类可以使20～40cm的水层形成附着丝状藻类、原生动物、腔肠动物、多孔动物和苔藓动物等多种附着生物，使N，P，COD和BOD5含量分别下降67．3％，73．2％，38．1％和15．5％，起到了明显控制富营养化的作用，同时还能收获珍珠、蚌肉和贝壳等产品。比其他控制方法具有更好的实际应用性。 相似文献
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目前,由中国科学院海洋研究所实验海洋生物学开放研究实验室、中国海洋湖沼学会与日本通商产业省工业技术院大阪国立研究所、日本贸易振兴会共同在青岛举办的“中日藻类基因工程及生物反应器学术讨论会”,吸引了中日30余家高校和科研单位的110余名专家学者与会。 会间笔者采访了出席中日藻类基因工程及生物反应器学术讨论会的中日有关科学家。 相似文献
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根据2006年5月～2007年5月逐月采集青岛沙子口近海作业的定置网具渔获物的分析与测定,记述了该海区出现的98种渔业生物,并进行了定置网渔获物组成的分析,分析了种类组成特点及生物多样性的季节变化情况.结果表明,本调查区域渔获物以小型低值鱼类、经济无脊椎动物和经济幼鱼为主,渔获个体偏小.据此提出了保护近海生物多样性与合理利用近海渔业资源的一些建议. 相似文献
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西湖水域初级生产力和富营养化的调查研究 总被引：3，自引：0，他引：3
1985年2月至1986年2月,对杭州西湖水域微生物现存量和初级生产力进行了逐月调查研究。结果表明,用细胞数和叶绿素a所表征的浮游藻类的生物量,用ATP所表征的活生物碳量及用测氧法和~(14)C同位素示踪法所测得的光合作用速率均为岳湖>西里湖>小南湖>外西湖>北里湖>>三潭内湖。文章评价了近几年对西湖治理的效果,即富营养化的发展得到一定控制,但目前仍属于重富养化生态系统。文章还提出了导致富营养化的关键营养元素之一磷与光合作用速率、透明度等的定量关系,并通过西湖的年初级生产量(5334.2吨有机碳)换算出年潜在鱼产最(约50万公斤)。文章指出,放养摄食浮游藻类的鱼类是减轻湖泊营养负荷的重要途径之一。 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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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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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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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. 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