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1.
根据2006年夏季正值8号超强台风"桑美"影响后大渔湾海域范围内15个取样站采集的大型底栖动物样本,分析研究了大渔湾海域大型底栖动物在台风影响后的分布状况.结果表明,在54种大型底栖动物中,多毛类为22种,软体动物为22种,甲壳类为5种,棘皮动物为3种,其它类为2种.站位大型底栖动物种数分布都在5～20种,其中S6站种类出现最多,达20种.大渔湾大型底栖动物平均生物量为18.6 g/m2,平均栖息密度为349个/m2.通过种类相似性聚类分析得出,该区大型底栖生物可划分为3个群落:群落Ⅰ为西格织纹螺-小头虫-小荚蛏群落;群落Ⅱ为奇异稚齿虫-不倒翁虫-西格织纹螺群落;群落Ⅲ为西格织纹螺-圆筒原盒螺群落;群落间的种类和数量呈明显差异.本次调查分析得到的该海域大型底栖动物种类数及数量值与1980年和1982年调查得到的结果相比,均有所增加,增加的原因可能是由于陆源营养物质的输入,使该海域的大型底栖动物得到较好的生长.尽管本次调查的大型底栖动物种类及数量与以前调查的有所差异,但构成该海域大型底栖动物种类的主要成分还是多毛类和软体动物. 相似文献
2.
胶州湾浮游藻类生态现象 总被引：23，自引：0，他引：23
胶州湾位于北纬35°55′～36°18′,东经120°04′～120°23′,面积为390km2,平均水深为7m ,是一个半封闭型海湾,良好的自然条件,滋润着丰富多样的生物群落。胶州湾浮游植物已鉴定的种类约175种,近年初级生产力(以C计)平均为503mg/(m2·d),浮游动物生物量约100mg/m3,已鉴定种类为110种,底栖动物平均生物量为73.6g/m2,栖息度为203.6个/m2,产量最高的经济底栖动物是菲律宾蛤仔[1]。此外,胶州湾是多种经济鱼、虾、蟹类的繁殖、发育和索饵场所,也是对虾、扇贝、海带等经济物种的养殖基地。胶州湾周围为青岛、胶州、胶南等城市所环抱,形成了高度… 相似文献
3.
为了解桑沟湾大型底栖动物多样性现状,作者于2009年7月和12月对桑沟湾9个站位进行2个航次的采样,以种类组成、生物量和栖息密度为基础,采用物种多样性指数(Shannon-Wiener index)、物种丰富度指数(Species richnessindex)以及物种均匀度指数(Species evenness index)对大型底栖动物多样性及其影响因子进行了分析。结果表明:共采到大型底栖动物83种,其中多毛类45种,占种类总数的54.22%,软体动物11种(占13.25%),甲壳类23种(占27.71%),其他4种(占4.82%)。各站获得平均种类数在2～28种之间,种类最少的出现在夏季的C8站,最多的出现在夏季的C4站。不同养殖区生物多样性指数差异也很大,物种多样性(H′)和物种丰富度指数(D)均以贝类养殖区最高,藻类养殖区最低,而物种均匀度指数(J′)以贝藻混养区最高,藻类养殖区最低。生物多样性除了受种的数量及其个体密度的影响外,还与多种环境因素有关,相关性分析结果表明:水温、盐度、沉积物类型和硫化物含量是影响桑沟湾大型底栖动物生物多样性的主要环境因子。 相似文献
4.
桑沟湾大型底栖动物生物多样性研究 总被引：3，自引：0，他引：3
为了解桑沟湾大型底柄动物多样性现状,作者于2009年7月和12月对桑沟湾9个站位进行2个航次的采样,以种类组成、生物量和柄息密度为基础,采用物种多样性指数(Shannon-Wiener index)、物种丰富度指数(Species richnessindex)以及物种均匀度指数(Species evenness index)对大型底栖动物多样性及其影响因子进行了分析.结果表明:共采到大型底栖动物83种,其中多毛类45种,占种类总数的54.22％,软体动物11种(占13.25％),甲壳类23种(占27.71％),其他4种(占4.82％).各站获得平均种类数在2～28种之间,种类最少的出现在夏季的C8站,最多的出现在夏季的C4站.不同养殖区生物多样性指数差异也很大,物种多样性(H′)和物种丰富度指数(D)均以贝类养殖区最高,藻类养殖区最低,而物种均匀度指数(J′)以贝藻混养区最高,藻类养殖区最低.生物多样性除了受种的数量及其个体密度的影响外,还与多种环境因素有关,相关性分析结果表明:水温、盐度、沉积物类型和硫化物含量是影响桑沟湾大型底栖动物生物多样性的主要环境因子. 相似文献
5.
为摸清福建兴化湾大型底栖动物的种类组成、生物多样性分布格局以及受扰动情况,于2013年7月、9月以及2014年2月、4月共四个航次进行了大型底栖动物调查。采用优势度指数、Shannon-Wiener多样性指数、Margalef’s丰富度指数和Pielou’s均匀度指数等方法,分析了该海域大型底栖动物的种类组成和生物多样性分布。结果表明,研究海域共鉴定出大型底栖动物132种,包括多毛类58种,甲壳类27种,软体动物33种,其他门类14种。四个季节的共同优势种均为多毛类,包括多鳃齿吻沙蚕(Nephtys polybranchia),寡鳃齿吻沙蚕(Nephtys oligobranchia),中蚓虫(Mediomastus californiensis)和异足索沙蚕(Lumbrineris heteropoda)。研究海域大型底栖动物的平均生物量为39.42g/m~2;平均栖息密度为311.67个/m~2;栖息密度和生物量平均值2014年4月最高(398个/m2,63.23g/m~2),2013年7月航次最低(252个/m2,7.77g/m~2)。不同站位,栖息密度和生物量不同。栖息密度最大值出现在1号站位(738个/m~2),最低值为12号站位(90个/m~2)。而生物量平均最大值出现在15号站位(108.17g/m~2),最低值出现在22号站位(8.72g/m~2)。丰富度指数、均匀度指数、Shannon-Wiener多样性指数的平均值分别为2.81、0.87和2.73,这三个指数,9月份均为最大,分别为3.20、0.93、3.12,4月份最小,分别为2.09、0.78、2.05。生物多样性指数和丰富度指数均表明福建兴化湾大型底栖动物群落受到一定的扰动。 相似文献
6.
本研究根据2017年8月和2018年8月在东海北部杭州湾和三门湾大型底栖动物的拖网采集资料,对这两个海域的大型底栖动物群落结构和多样性进行了研究。杭州湾的10个站位和三门湾的6个站位共获得61种大型底栖动物,其中甲壳动物最多(22种),其次是鱼类(20种)、软体动物(14种)、棘皮动物(2种)、刺胞动物(2种),多毛类最少(1种)。杭州湾大型底栖动物优势种出现3种,三门湾出现8种,脊尾白虾Palaemoncarinicauda是两个海域唯一的共同优势种。相比2017年,杭州湾和三门湾在2018年鱼类的种类和数量都有明显的增长。根据大型底栖群落的多样性指数,杭州湾不同区域的生物多样性差异较大,而三门湾则较为平均。对杭州湾和三门湾大型底栖动物进行聚类分析和nMDS排序分析,结果表明,杭州湾不同站位大型底栖动物相似度低,Q8、Q9、Q10站位群落结构与三门湾的站位更为接近,三门湾的底栖群落在2017年和2018年存在较大差异。杭州湾和三门湾大型底栖动物群落的变化可能与环境因子、人类活动、厄尔尼诺事件等的变化相关。 相似文献
7.
乐清湾大型底栖动物种类和数量组成特征及变化 总被引：2，自引：0，他引：2
为了解和掌握乐清湾大型底栖动物种类和数量组成特征及变化情况,本研究于2015年1月、3月、5月、8月和10月进行5个航次的大型底栖动物调查。结果表明,乐清湾共有大型底栖动物116种,环节动物为主要优势类群;种类组成、栖息密度和生物量在不同航次之间均存在较大幅度的波动;相同航次之间的种类组成、栖息密度和生物量在空间分布也存在明显斑块化。通过对比分析历史研究数据发现乐清湾的大型底栖动物种类和数量组成变化明显,其中小个体环节动物的种类数和栖息密度明显升高,而大个体软体动物和棘皮动物的种类数和栖息密度则下降明显。这说明乐清湾底栖生境处于不稳定状态,需要在长期稳定的生境中生长的大个体动物不能得到充分的生长,取而代之的是出生率高,生长周期短的小个体r-对策者的快速繁殖。 相似文献
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作者对秦山核电站邻近水域进行了春、夏、秋、冬(1989年4月～1990年1月)四个航次的综合调查。结果表明,该区域大型底栖动物的生物量和个体数量极为贫瘠(分别为0.03g/m~2和2.0个/m~2),生物种类组成简单,经鉴定有33个种类,并有明显的季节变化。底栖动物群落结构表现出鲜明的河口或近岸性广温低盐的生态特点。属杭州湾的白虾—长臂虾群落,夏季棘头梅童鱼Collichthys lucidus占绝对优势。水动力因子、沉积作用和盐度是决定调查区域底栖动物种类、数量和分布的关键因子,而季节变化则主要受温度所控制。 相似文献
10.
南麂列岛海域微小型底栖藻类生态研究 总被引：6，自引：0，他引：6
本文首次报道南麂列岛海域沉积物中的微型（２～２０μｍ）、小型（２０～２００μｍ）藻类组成、数量分布及其与环境因子的关系。经初步鉴定，沉积物中共有微小型藻类２４属７１种，其中小型的底栖圆筛藻属Ｃｏｓｃｉｎｏｄｉｓｃｕｓｓｐｐ．为２１种，广布于整个海区，春季平均细胞密度为（１０．４±３．６）×１０３个／ｃｍ２，占总密度的６５．４％；微型藻以中肋骨条藻Ｓｋｅｌｅｔｏｎｅｍａｃｏｓｔａｔｕｍ占优势，秋季平均细胞密度为（４２６２．８±１１９２８．２）×１０３个／ｃｍ２，占总细胞密度的９８．９％，主要分布在沿岸区。对０～１２ｃｍ柱状样品中细胞密度分层分析结果表明，０～２ｃｍ层的细胞密度大于２～５ｃｍ层大于５～１２ｃｍ层。沿岸区（１，２，５，６，７，８，９站）的种类和细胞密度高于岙口（３站）、远岸（１０站）及水道区（４站）。根据微小型底栖藻类组成特点，可划分为三个生态类群：广布性类群、暖水性类群和温带性类群。微小型底栖藻类密度与营养盐浓度的季节变化密切相关，秋季高于春季。 相似文献
11.
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
12.
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
13.
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,(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
16.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included. 相似文献
19.
Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
20.
Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献