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1.
鳚亚目4科33属95种,鰕虎鱼亚目5科98属259种,刺尾鱼亚目5科11属65种,鲈形目19亚目104科535属1799种。  相似文献   

2.
隆头鱼亚目5科63属316种,鰧鱼亚目8科19属53种,绵鳚亚日3科7属8种,玉筋鱼亚目1科3属3种。  相似文献   

3.
鳚亚目 4 科 33 属 95 种,鰕虎鱼亚目 5 科 98 属 259 种,刺尾鱼亚目 5 科 11 属 65 种,鲈形目 19亚目 104 科 535 属 1799 种。  相似文献   

4.
中国鱼类名录Ⅸ--魣亚目、马鲅亚目、鲈亚目(部分)   总被引:2,自引:0,他引:2  
魣亚目1科1属11种,马鲅亚目1科2属5种.鲈亚目(部分)记述23科.  相似文献   

5.
鲈亚目 3 总科 53 科 239 属 840 种。  相似文献   

6.
中国近海共有枝鳃亚目、蓑海牛亚目软体动物40种,隶属于16科30属,主要分布在浙江以南的热带、亚热带海区,有些种类向北可以分布到达黄、渤海,部分种类仅分布于黄、渤海。区系性质属于印度,西太平洋区的中国,日本亚区。  相似文献   

7.
鲈亚目3总科53科239属840种.  相似文献   

8.
鲽形目3亚目8科51属142种。鲀形目2亚目9科57属143种。海蛾鱼目1科2属3种,鮟鱇目3亚目11科23属41种。  相似文献   

9.
甲壳类蔓足亚纲(Subclass Cirripedia) 围胸目(Order Thoracica) 现今分为4亚目:茗荷亚目Lepadomorpha; 短茗荷亚目Brachylepadomorpha, 花笼亚目Verrucomorpha和藤壶亚目Balanomorpha。茗荷亚目是有柄蔓足类,为最原始的亚目。它的躯体分为头部和柄部。软体部分包在头部由外套膜和壳板(或无壳板)围成的腔内。柄部有肌肉层,用以附着于其他物体(或动物)上。茗荷亚目的种栖息于潮间带、潮下带至深海底,绝大多数附着于岩石、底栖动物(贝壳、水螅、珊瑚、海胆、十足甲壳类等)或其他物体上,少数种(如茗荷科Lepadidae 的一些种)附着于木材、船底、漂浮及游泳动物(如鲸类、海垫、海龟等),营漂游生活。搞清这类动物的种类对于潮间带生物群落的分析、底栖生物生态的研究及附着生物的防除等工作都具有重要意义。 茗荷亚目在国内仅有零星报道,尚缺乏系统研究。作者整理了中国科学院海洋研究所历年来采集收藏的标本,其中大部分为1975 一1978年东海大陆架海洋调查获得,少部分为全国海洋综合调查和潮间带及沿岸调查所采集。经鉴定共有55种,分隶于3总和7科26属,其中一种为新种,24种为我国首次记录。 在我国近海发现的有柄蔓足类,除少数种,如茗荷Lepas anatifera anatifera, 蟹板茗荷Octolasmis neptuni等在各海区广布外,大部分种仅出现在南海和东海,属于印度西太平洋区的暖水种,少数温带种分布范围仅限于渤海和黄海,有的也在东海出现,如朝鲜弱铠茗荷Abathescalpellum koreanum和中直铠茗荷Litoscalpellum intermedium等。 就世界范围而言,有柄蔓足类资料比较分散;其形态变异较大,不易鉴定;有的种仅在个别地点发现,或获得标本很少,种的正确鉴定存在一定困难;因而同物异名较多。本文对一些种进行了必要的修订。  相似文献   

10.
藤壶亚目是目前为止海洋生物群落中种类最丰富和最重要的类群之一,也是海洋污损生物的重要组成部分,主要分布于岩石潮间带栖息地、深海热液口,有的物种会附着在红树林植物、动物和人工构筑物上。文章综述了藤壶亚目的起源以及分类系统的建立和发展,认为藤壶亚目在下白垩纪从有柄目分化而来,其中篱藤壶科(小藤壶总科)是最早分化出的一支,而后逐渐分化为星板藤壶总科、厚藤壶总科、鲸藤壶总科、笠藤壶总科、小藤壶总科和藤壶总科6支;总结了国内藤壶亚目的研究进展;比较了藤壶亚目系统发育学的研究方法;展望了未来的研究方向,即结合形态学方法与分子系统学方法研究藤壶亚目物种的系统发育关系,为今后研究藤壶亚目物种的分类及防治等工作提供借鉴和帮助。  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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