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1.
报道采自山东沿海贝类鳃表及外套腔中寄生 /共栖的 3种吻毛类纤毛虫 :原生钩毛虫(Ancistrocoma primigenius)、派氏钩毛虫 (Ancistrocoma pelseneeri)及威海下毛虫 (Hypocomidesweihaiensis)。作者依据活体观察、蛋白银和银浸法染色对其活体形态学、纤毛图式及银线系进行了综合描述。该研究系钩毛虫属纤毛虫在我国的首次报道。  相似文献   

2.
报道山东沿海贝类鳃表及外套腔中共栖的 3种触毛亚目盾纤类纤毛虫 :厚鱼钩虫(Ancistrum crassum)、日本鱼钩虫 (Ancistrum jap onicum)及亚桶形后口虫 (Boveriasubcylindrica)。文中依据活体观察、蛋白银及银浸法染色对其活体形态学、纤毛图式及银线结构进行了综合描述 ,对采自 4种不同宿主的厚鱼钩虫种群进行了比较研究。该文系后口虫属纤毛虫在我国的首次报道。  相似文献   

3.
报道山东沿海贝类鳃表及外套腔中共栖的 2种盾纤类纤毛虫 ,含 1新种 :大粘叶虫(Myxophyllum magnum n.sp.)及 1种国内新记录 :双壳吸触虫 (Thigmophrya bivalviorum)。作者依据活体观察及蛋白银染色对其活体形态学、纤毛图式进行了综合描述 ,并对粘叶虫属和吸触虫属属的定义做了新的修订。  相似文献   

4.
报导了从中国对虾(Penaeus orientalis Kishnouye)越冬亲虾血淋巴内分离的盾纤毛目纤毛虫一新亚种,隶属于嗜污科(Philasteridae)拟阿脑虫属(Paranophrys),系蟹栖拟阿脑虫(Paranophrys carcini)一新地理亚种,定名为旋毛蟹栖拟阿脑虫,新亚种(Paranophrys carcini spiralis subsp.nov.)。本工作对该亚种做了蛋白银染色、银浸法、孚尔根染色,以显示其银线系、纤毛下器及细胞核器,并结合扫描电镜对虫体形态作了观察与鉴定。文内对该亚种的形态学作了描述并列表比较了所在属诸种主要性状特征以及本新亚种与相似种在形态特征上的主要差别,以确定新亚种的成立。  相似文献   

5.
利用活体观察、蛋白银染色技术对淡水腹毛目纤毛虫—锈色尖毛虫 (Oxytricha ferrug-inea Stein,185 9)的青岛种群之活体形态学及纤毛图式做了研究。其特征如下 :虫体浅黄褐色 ;表膜下颗粒为铁锈色 ,聚合成组并作纵向不规则排列。口围带平均小膜数为 35。额、腹、横棘毛为典型8∶ 5∶ 5方式排布 ;尾棘毛恒为 1根。背触毛 5列 ,其中 4列完整 ,1列不完整。伸缩泡位于体左侧前1/ 3处 ,具两根收集管。与相近种比较表明 ,O.ferruginea与前人所报道的另一淡水种 O.aerugi-nosa极可能是同一种 ,因此本文建议将两者合并。  相似文献   

6.
利用活体观察和蛋白银染色技术对鬃异源棘尾虫(Tetmemena pustulata(Müller,1786)Eigner,1999)漠河种群的形态学及细胞发生学进行了详尽的研究。研究表明:本种群与其他种群在活体形态和纤毛图式特征方面十分吻合。无性生殖期间细胞发生学表现出的主要特征如下:1)老口围带为前仔虫所继承,老波动膜仅在前部发生更新;2)后仔虫口原基为表层独立发生;3)老棘毛II/2、III/2与IV/3、IV/2、V/4分别参与前、后仔虫额-腹-横棘毛原基的构建;4)前、后仔虫额-腹-横棘毛原基I-VI以“1∶3∶3∶3∶4∶4”的方式分化形成棘毛;5)前、后仔虫的缘棘毛原基分别由老结构反分化形成;6)背触毛发生为尖毛虫模式,但2列背缘触毛原基源于右缘棘毛原基前端断裂。本研究为该种背缘触毛原基起源的首次揭示。  相似文献   

7.
报道了6种采自青岛地区的土壤纤毛虫,包括两种国内新纪录:尖顶管叶虫,苔藓长颈虫。文中对所涉种类的活体形态、银线系和纤毛下器等做了详细描述。  相似文献   

8.
报道了采自青岛胶州湾的菲律宾蛤仔鳃丝上寄生的一种触毛类纤毛虫,经鉴定为厚鱼钩虫(AncistrumcrassumFenchel,1965)。本文运用活体观察和蛋白银法对其活体形态及纤毛图式进行了详细描述。此为我国新记录,同时也是触毛亚目纤毛虫在我国的首次报道。  相似文献   

9.
研究扇贝外套腔内栖生的纤毛虫一蠕状康纤虫Cohnilembusverminus(Muller,1786)的形态、核器及纤毛图式。结果显示其口器结构为;M1呈单列结构,约占体长的1/2,M2由4组毛基粒构成,PM起自M2末端,Sc约由5个毛基粒构成。此外,还列表比较了不同作者报导的C.verminus种群及其它6种已知的康纤虫的主要性状特征。  相似文献   

10.
依据干银法和蛋白银染色法研究了山东沿海养殖鱼类的4种寄生车轮虫属纤毛虫: 直钩车轮虫、杜氏车轮虫、日本车轮虫及小袖车轮虫, 其中直钩车轮虫为我国的新记录.作者对采自不同宿主的直钩车轮虫种群的形态学特征进行了比较描述, 对所涉车轮虫的形态学、宿主、分布、流行情况及危害程度等做了综合报道.  相似文献   

11.
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.
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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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