首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
台湾海峡中北部海洋线虫群落的种类组成及分布   总被引:3,自引:0,他引:3  
1998年2月对台湾海峡中北部3个断面13个取样站进行了自由生活海洋线虫调查,获得了海洋线虫100种,隶属于3目28科91属,其中密度较高的种有萨巴线虫(Sabatieria sp.1)、变异矛咽线虫(Dorylaimopsis variabilis)、Vasostoma sp.、花斑线虫(Spilophorella sp.)、吞咽线虫(Daptonema sp.)、Linhystera sp.1、吸咽线虫(Halalaimus sp.1)和(Filoncholaimus sp.)等。虽然这些海洋线虫绝大多数只鉴定江口外海降低。从优势种分布看,不同取样站其密度差异很大。海洋线虫的取食类型以选择性食沉积物者(1A)占优,有38种,但刮食性种类(2A)和非选择性食沉积物者(1B)也分别为29种和25种,表明了台湾海峡中北部海洋吸虫取食类型的复杂性。文中还探讨了海洋线虫分布与海流等环境因子的关系。  相似文献   

2.
2002年6月30日和7月1日在厦门海域2个采样点取样,对厦门东西海域自由生活海洋线虫的群落结构进行了初步比较研究.结果显示:2个站位共鉴定自由生活海洋线虫53种,西海域37种,东海域31种,其中优势种是茅咽线虫Dorylaimopsis variabilis.、萨巴线虫Sabaticria sp.、霍帕线虫Hoppcria sp.、海洋拟齿线虫Parodontophora marina 和星火线虫Marylymnia sp.;对海洋线虫群落结构和生物多样性指数的比较表明,2个站位的群落多样性指数和优势种基本一致,但优势种的优势度有一定差异.西海域站位出现的种类多,但种类分布不均匀;东海域出现的种类少,但种类分布较均匀.非选择性沉积食性者(即1B型)和底上硅藻食性者(即2A型)是该海域两个站位的优势摄食类群.从优势种和摄食类群方面来看,厦门海域与台湾海峡南部、黄河口站位海洋线虫群落有一定的相似性.  相似文献   

3.
宋慧丽  慕芳红  孙燕  华尔 《海洋学报》2021,43(8):139-151
本研究于2015年12月在濒临渤海的大连夏家河子沙滩和濒临黄海的大连金沙滩采集海洋线虫样品,对两处砂质潮间带海洋线虫群落结构及多样性特征进行了研究。研究结果表明,两处砂质潮间带海洋线虫丰度、优势种、摄食结构及多样性差异显著。夏家河子海洋线虫平均丰度为(592.0±318.9) ind./(10 cm2),金沙滩海洋线虫平均丰度为(54.6±53.8) ind./(10 cm2),显著低于夏家河子。共鉴定海洋线虫43种,共有种13个。夏家河子沙滩海洋线虫优势种为Daptonema sp.1、Daptonema sp.2、Theristus sp.1、Setosabatieria sp.1、Prochromadorella sp.1、Daptonema sp.3、Paracyatholaimus sp.1、Sabatieria breviseta,以非选择性沉积食性线虫为主;金沙滩海洋线虫优势种为Oncholaimus sp.1、Chromadorita sp.1、Theristus sp.2, Neochromadora sp.1、Enoplus sp.1、Prochromadorella sp.1,以杂食性或捕食性线虫为主。两处砂质潮间带海洋线虫种数S、丰富度指数d和香农?威纳多样性指数H'存在极显著的差异,其值均表现为夏家河子显著高于金沙滩。相似性分析结果显示,两处沙滩的海洋线虫群落结构存在显著差异。间隙水pH、沉积物有机质含量及中值粒径是引起海洋线虫群落结构及多样性差异的主要因子,其中,沉积物中值粒径对线虫群落特征的影响最为突出。就两处沙滩潮区差异而言,受沉积物粒径特征及pH的影响,夏家河子海洋线虫群落特征在不同潮区之间也存在差异,其低潮带海洋线虫多样性高于高、中潮带,杂食者和捕食者丰度高,反映其海洋线虫群落结构较复杂。金沙滩不同潮区的环境因子无显著差异,线虫群落结构及多样性潮区差异不显著,较为均一。此外,水动力对海洋线虫群落结构沙滩差异和潮区差异也产生重要影响。一方面,水动力通过影响不同粒径沉积物的沉积影响海洋线虫群落特征;另一方面,水动力可影响线虫的分散性,进而对其潮区分布产生影响。  相似文献   

4.
分别于2013年7月(夏季)、2013年10月(秋季)、和2014年1月(冬季)在深圳福田红树林保护区选取沙嘴码头(S)、凤塘河口(F)、观鸟屋(G)和基围鱼塘(Y)四个采样区10个采样站点采集样品,探讨海洋线虫在该红树林保护区的丰度、群落结构及其时空变化规律。结果表明,福田红树林保护区海洋线虫群落平均丰度为(1 591.4±84.8) ind./10 cm~2,丰度变化范围与中国其他红树林生境基本一致。海洋线虫群落以轴线虫科(Axonolaimidae)和条线虫科(Linhomoeidae)为优势科,假拟齿线虫属(Pseudolella)、拟齿线虫属(Parodontophora)、微口线虫属(Terschellingia)、吞咽线虫属(Daptonema)、亚囊咽线虫属(Subsphaerolaimus)、后线形线虫属(Metalinhomoeus)等为优势属,刮食者(2A型)为优势摄食类型。优势属组成与中国各地红树林生境相似,表明海洋线虫群落种类组成相似。但是,仍有部分属或种的优势度仅在福田红树林生境较高,具有典型的地方性分布特点。福田红树林线虫群落结构和丰度具有显著的空间差异和季节性变化特征。季节动态主要表现为夏季丰度极高,秋冬季丰度低,三个季节种类组成区分度明显。线虫群落结构和丰度的空间差异主要表现为区域差异显著,而潮带差异不显著,表明同一区域线虫群落结构基本一致。区域差异表现为S区线虫丰度最高,F区丰度最低;线虫种类组成在Y区、S区和F区之间存在显著差异。从摄食结构而言,Y区以非选择性沉积食性线虫为优势,其他三区以刮食者为优势摄食类型。相关性分析结果显示,间隙水温度、盐度、沉积物粉砂黏土含量或中值粒径、脱镁叶绿酸、有机质含量等与线虫群落结构和丰度显著相关。植被类型差异、沉积物粒度特征的差异和有机质含量代表的食物资源差异是引起线虫群落空间差异的主要原因,间隙水温度、盐度、沉积物粒度特征的变化是引起季节差异的主要因素。海洋线虫群落的空间差异和季节性动态也是对变化中的红树林环境特征的响应。  相似文献   

5.
南黄海冬季自由生活海洋线虫群落结构的研究   总被引:7,自引:0,他引:7       下载免费PDF全文
采用现场调查和室内分析方法,对2003年1月南黄海鳀鱼越冬场调查航次中22个站位所取得的小型底栖生物沉积物样品进行了分析研究。结果表明,自由生活海洋线虫是最优势类群,占整个小型底栖生物总丰度的87.1%。不同站位线虫的丰度从每10cm2505条到1272条不等[平均(831±247)×10-1ind/cm2]。其中80.1%的线虫分布在表层(0-2cm)沉积物中。共鉴定出线虫223种或分类实体,隶属于145属、32科、4目,主要优势种是Dorylaimopsis rabalaisi、Terschellingia longicaudata、Sphaerolaimus balticus、Quadricoma scanica、Paramonohystera riemanni、Vasostoma spiratum和Promonhystera faber等。营养结构中沉积食性者(1A 1B)占优势;线虫群落中幼龄个体一般占到线虫群落个体总数的60%以上;雌雄比例平均为1︰0.79。分析检验显示研究站位冬季线虫的种类组成应属于一个群落,两个亚群落,总体上属于潮下带泥质生境冷水性群落。相关分析表明线虫丰度与水温和盐度显著相关;种类组成和多样性与Chl-a和Pha-a显著相关。线虫的丰度和生物量均与Chl-a的含量显著相关;线虫的种类数与有机质含量、含砂量呈显著相关,与Chl-a和Chl-a Pha-a极显著相关。  相似文献   

6.
厦门凤林红树林湿地自由生活海洋线虫群落的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
郭玉清 《海洋学报》2008,30(4):147-153
2004年冬季在集美凤林类似底质类型、盐度和潮位的海湾地段4个断面,就不同红树植物林中的小型底栖动物数量和自由生活海洋线虫群落进行了研究。结果表明:海洋线虫是凤林红树林中小型底栖动物中的绝对优势类群,占到小型底栖动物的76.1%~96.3%;从丰度来看,旧区白骨壤(Avicennia marina)林中小型底栖动物的数量较少,有污水流过的光滩数量较大;4个断面共鉴定出海洋线虫37种(分类实体单元),其中新区秋茄(Kandelia candel)林中的生物多样性指数较低,旧区白骨壤林中群落具有较高的物种多样性;从出现的物种来看,新区秋茄林、旧区白骨壤林和光滩上出现的优势种和摄食功能群的类型各不相同。从4个断面13个站位进行的聚类分析和MDS标序分析结果推断自由生活海洋线虫的群落结构与不同的红树植物形成的沉积物有关。  相似文献   

7.
北黄海小型底栖生物丰度和生物量时空分布特征   总被引:1,自引:0,他引:1  
分别于2006年7月和2007年1,4和10月在北黄海陆架浅海水域进行小型底栖生物调查.结果表明,4个航次的小型底栖生物平均丰度分别为(1 099±634),(664±495),(1 601±837)和(524±378) ind·10 cm-2;平均生物量分别为(1 446.34±764.66),(428.63±294.84),(1 580.53±1 041.23)和(793.50±475.83) μg·dwt·10 cm-2.共鉴定出18个小型底栖生物类群,按丰度,自由生活海洋线虫为最优势类群,4个航次的优势度分别为72%,90%,85%和74%,其他优势类群依次是桡足类、多毛类、动吻类和介形类;按生物量依次是线虫、桡足类、多毛类、介形类和双壳类.97%的小型底栖生物分布在0~5 cm的表层沉积物内,线虫和桡足类分布在0~2 cm沉积物的比例分别为86%和87%.二因素方差分析(two-way ANOVA)表明:小型底栖生物丰度和生物量在由4个航次所代表的春、夏、秋、冬各季节之间存在显著差异(春、夏高于秋、冬),在4个航次的5个相同取样站位之间也有显著差异.小型底栖生物的丰度和生物量与水深和底盐呈负相关性.北黄海冷水团对小型底栖生物丰度和生物量时空分布有一定的影响.  相似文献   

8.
利用 1 998年“大洋一号”调查船 DY95 - 8航次在中国多金属结核开辟区东、西两小区用多管取样器采集的沉积物样品 ,对小型底栖动物的组成、分布及其与环境因子的关系进行了研究。结果表明 :(1 )东、西两小区共有 1 6个类群的小型底栖动物 ,其中线虫类占居显著优势 ,在东、西两小区各占总栖息密度的 71 %和 6 4 %,其次为猛水蚤类和蜱螨类。 (2 )东、西两小区小型底栖动物类群平均栖息密度分别为 3 2 .47ind/1 0 cm2 和 1 8.0 5 ind/1 0 cm2 ,东小区高于西小区。小区各站位间的栖息密度平面分布差异显著。 (3 )东、西两小区小型底栖动物类群栖息密度的垂直分布趋势明显 ,由表层向底层 ,栖息密度逐渐降低。 (4)东、西两小区小型底栖动物空间分布与底质沉积物、结核覆盖率和底层流等环境因子密切相关 ,底质较硬、结核覆盖率较高以及底层流较强都不利于小型底栖动物的栖息。  相似文献   

9.
台湾海峡地区雾形成的天气类型分析   总被引:1,自引:0,他引:1  
利用 1 980— 1 997年东亚逐日 0 8时地面天气图资料 ,归纳并分析了台湾海峡地区(2 0°— 2 7°N ,1 1 5°— 1 2 5°E)形成雾的 4种天气类型 ,它们分别是冷平流主导型、暖平流主导型、均压场型和台风外围型 ,为台湾海峡地区雾的预报提供天气学参考。  相似文献   

10.
台湾海峡西部海域软质海底多毛类的生态   总被引:2,自引:0,他引:2  
吴启泉 《台湾海峡》1993,12(4):324-334
本文根据1984-1985年4航次底栖生物调查资料,首次全面地研究了台湾海峡西部海域多毛类的种类组成,数量分布及其与环境因子的关系。结果表明,该海域多毛类404种,习见种191种,区系属亚热带性质;平均生物量4.33g/m^2,平均栖息密度68个/m^2;有沿岸性和外洋性两种明显不同的生态类型,前者位于沿岸水系常年控制海域,种类多,数量较大,后者位于南部粗粒沉积物分布区,种类较少;多毛类高数量区与  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
18.
19.
《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   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号