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1.
鲍苗硅藻饵料培养池中的危害性纤毛虫及其优势种群研究 总被引：4，自引：0，他引：4
应用纤毛虫的定性和定量方法,研究了规模化鲍苗硅藻饵料培养池中危害性纤毛虫的种类组成和各种类的种群变化过程,共观察到纤毛虫33种,斯坦盾纤虫Aspidiscasteini和三齿盾纤虫Aspidisca tridentata为优势种,在藻类培养过程中,危害性纤毛虫种类数量呈先增加后减少,最后时有25种,随着培养的藻类数量增加,纤毛虫数量也有所增加,在培养的第13天达到数量的最大值,其最大总密度可达21．28和21．55个.cm^-2,优势种斯坦盾纤虫和三齿盾纤虫最大密度达到5．3－7．2个.cm^-2,此外,大突口虫Condylostomamagnum,扇形游仆虫Euplotes vannus,具棘旋毛虫Dysteriaspinifera和双眉虫属Diophrys在数量上具有较高的比例,与藻类不同的是,纤毛虫的密度在达到最大后逐渐下降。 相似文献
2.
应用纤毛虫的定性和定量方法 ,研究了规模化鲍苗硅藻饵料培养池中危害性纤毛虫的种类组成和各种类的种群变化过程。共观察到纤毛虫 33种 ,斯坦盾纤虫Aspidiscasteini和三齿盾纤虫Aspidiscatridentata为优势种。在藻类培养过程中 ,危害性纤毛虫种类数量呈先增加后减少 ,最多时有 2 5种。随着培养的藻类数量增加 ,纤毛虫数量也有所增加 ,在培养的第 1 3天达到数量的最大值。其最大总密度可达 2 1 2 8和 2 1 55个·cm- 2 。优势种斯坦盾纤虫和三齿盾纤虫最大密度达到 5 3— 7 2个·cm- 2 。此外 ,大突口虫Condylostomamagnum ,扇形游仆虫Euplotesvannus,具棘旋毛虫Dysteriaspinifera和双眉虫属Diophrys在数量上具有较高的比例。与藻类不同的是 ,纤毛虫的密度在达到最大后逐渐下降 相似文献
3.
在使用表层海水作养殖水的杂色鲍(Haliotis diversicolor)养成池,整个养成阶段共检测到浮游纤毛虫33种,其中寡毛目(Oligotrichida)的种类最多,为14种。在一个使用沙井水作养殖水的杂色鲍养成池周年研究中,共观察到浮游纤毛虫24种。2类养成池的纤毛虫优势种都是尾丝虫(Uronema sp．)、钟虫(Vorticella sp．)和具沟急游虫(Strombidium sulcatum)。虽然后者养殖用水为沙井水,但养殖密度较大,水体交换量稍低,养殖水体中有机质含量高,嗜污性纤毛虫得以大量繁殖,其密度较前者高一倍。在养殖用水取水海区——红海湾近岸表层海水中,共检测到浮游纤毛虫27种,其中砂壳亚目(Tintinnina)纤毛虫16种。受水环境中二氧化碳浓度变化影响,养成池与取水海区砂壳虫的种类组成和密度有较大区别。 相似文献
4.
鲍人工养成阶段养殖环境中的周丛纤毛虫 总被引：2，自引：1，他引：2
应用定性和定量方法,研究了人工养成阶段杂色鲍Haliotis diversicolor外壳的周丛纤毛虫的种类组成和优势类群演变。共观察到3纲9目35属58种纤毛虫,缘毛类Peritrichida的种类最多,有23种。在养成阶段的早期,周丛纤毛虫的优势类群为钟虫类;在养成阶段的中、后期,周丛纤毛虫的优势类群演变为聚缩虫类,其中交替聚缩虫Zoothamnium alternans占绝对优势;文中还对各种环境因子对养殖环境中的周丛纤毛虫的影响进行了分析。 相似文献
5.
研究了杂色鲍(Haliotisdiversicolor)越冬期养殖环境中的浮游动物种类组成和密度变化。共检测到浮游动物33种,其中纤毛虫(Ciliata)23种,鞭毛虫(Mastigophora)5种,轮虫(Rotatoria)4种,桡足类(Copepoda)1种。优势种是奇异猛水蚤(Miraciaefferata)和海洋尾丝虫(Uromenamarinam);钩状狭甲轮虫(Colurellauncinata)和偏体虫(Dysterialancolata)为常见种。砂井水养殖可以减少养殖环境中原生动物以外的各种浮游动物种类。 相似文献
6.
热带西太平洋浮游纤毛虫的垂直分布 总被引：3，自引：2，他引：1
于2014年12月至2015年1月在热带西太平洋沿台湾南部到雅浦海山一个断面和雅浦海山海区研究了浮游纤毛虫丰度和生物量的垂直分布。浮游纤毛虫丰度变化范围为0—635ind./L,生物量范围为0—1.53μg C/L,丰度和生物量高值分布于200m以浅,其中,砂壳纤毛虫丰度为0—45ind./L,占总纤毛虫丰度的比例在0—14.62%之间。浮游纤毛虫丰度垂直分布均呈现"双峰型"模式:在表层和叶绿素极大值层(DCM)出现高值。共鉴定出砂壳纤毛虫33属76种。雅浦海山海区优势种为纤弱细瓮虫、卢氏真铃虫、管状真铃虫、膨大波膜虫,西太平洋海区优势种为纤弱细瓮虫、海勒斯真铃虫、酒杯类管虫、尖锐号角虫。有些种类分布在100m以浅,有的种类分布在100m以深,说明砂壳纤毛虫在100m水深左右种类发生变化。 相似文献
7.
夏季南海北部沙壳纤毛虫种类组成及空间分布 总被引：1，自引：0，他引：1
2007年8月夏季中国科学院南海海洋研究所南海北部开放航次期间,在北纬18°-22°,东经107°-122°范围内使用＂实验三号＂科考船进行了水体中沙壳纤毛虫的采样研究,探讨了沙壳纤毛虫的空间分布和种类组成。在36个站位中共鉴定出24属44种沙壳纤毛虫,其中优势种为长形旋口虫Helicostomella longa和根突拟铃虫Tintinnopsis radix,沙壳纤毛虫丰度变化范围为0–2200cell/L,平均丰度为221cell/L,从沿岸向外海方向,沙壳纤毛虫种类和丰度逐渐减少,其中A1站丰度最高（2200cell/L）,种类数最多（10）。夏季南海北部沙壳纤毛虫丰度与叶绿素a呈显著正相关,而与温度相关性不明显。夏季南海北部的上升流和珠江冲淡水携带的营养盐刺激了浮游植物的生长,影响着南海北部沙壳纤毛虫的种类组成和空间分布。 相似文献
8.
于2012年11月18日至12月21日,在黄、东海沿从南向北(26~36°N)一个断面24个站采样调查了表层(4 m)砂壳纤毛虫群落。共发现砂壳纤毛虫17属,32种。各站砂壳纤毛虫种丰富度为2~15种,砂壳纤毛虫总丰度为2 478~88 550个/m3。整个断面优势种为筒状拟铃虫、白领细壳虫、小领细壳虫和钝囊坎虫。巴西拟铃虫仅出现在青岛近岸(24号站),但丰度很高(10 960个/m3)。砂壳纤毛虫种类多样性从南向北降低,从近岸向远岸增加,黏着壳的比例在近岸水浅处较多,在水深大于50 m的站位,透明壳所占比例大大增加。不同种类的砂壳纤毛虫有着不同的分布区域,根据分布区域的不同,可分为南方种,北方种和广布种等。聚类分析结果显示,调查区的砂壳纤毛虫可以分为3个群落。 相似文献
9.
报道了2009年夏季北部湾A、B两个断面浮游纤毛虫的丰度和生物量。纤毛虫的平均丰度为521±369个·L-1,平均生物量(以碳为单位)为0.63±0.54μg·L-1。表层纤毛虫丰度和生物量的水平分布格局基本一致,高值主要位于湾的北部近岸、西南部近岸及湾中部A5站。两个断面纤毛虫丰度和生物量的垂直分布特点不同,纤毛虫在A断面水体中的垂直分布较均匀,在B断面主要分布在15m层以浅。共鉴定出砂壳纤毛虫13属20种,其中较为优势的种类为原始筒壳虫Tintinnidium primitivum、薄壳真铃虫Eutintinnus tenuis、三亚条纹虫Rhabdonella sanyahensis、未定种砂壳纤毛虫和斯氏拟铃虫Tintinnopsis schotti,且表现出不同的水平分布和垂直分布规律。 相似文献
10.
《热带海洋学报》2016,(3)
根据2014年春季(4月)白沙湾海域3个功能区域(鱼类网箱养殖区、贝藻混养区、非养殖区)13个站位生物和环境的调查资料,对浮游纤毛虫的群落特征进行分析,并且探讨了影响浮游纤毛虫群落变动的主要环境因素。结果表明:共检出19种纤毛虫,隶属于6目11属;纤毛虫丰度范围为80~3740个×L~(-1),平均丰度为995.4±123.1个×L~(-1),以环毛目(Cyclotrichida)、急游目(Stombidiida)和砂壳目(Tintinnida)为主;优势种包括红色中缢虫(Mesodinium rubrum)、锥形急游虫(Strombidium conicum)、百乐拟铃虫(Tintinnopsis beroidea)、球形急游虫(Strombidium globosaneum)、小拟铃虫(Tintinnopsis minuta)和锥形旋曳尾虫(Spirotontonia turbinata)。纤毛虫群落结构存在显著的空间差异,种类数及丰度呈现鱼类网箱养殖区偏低,而贝类混养区和对照区较高的特征。通过冗余分析(redundancy analysis,RDA)多元分析发现,白沙湾浮游纤毛虫群落结构差异主要与水体营养盐水平和叶绿素a浓度有关。 相似文献
11.
Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
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. 相似文献
12.
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
13.
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
14.
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. 相似文献
15.
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
16.
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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Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations. 相似文献
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《海洋学报(英文版)》2014,(9):F0003-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