共查询到20条相似文献，搜索用时 144 毫秒
1.
本文根据2014年至2017年在厦门文昌鱼保护区黄厝、南线十八线、鳄鱼屿和小嶝岛四处潮下带以及参照点白城潮下带获得的大型底栖动物和沉积物粒径数据,探讨底质细化对厦门潮下带文昌鱼栖息地大型底栖动物群落的影响。聚类分析表明个别黏土含量较高的取样站没有发现文昌鱼且大型底栖动物种数少。单因素方差分析表明,厦门潮下带部分大型底栖动物群落参数和优势种数量存在显著差异。底质粒径分析表明, 2017年9月,鳄鱼屿和白城潮下带黏土和粉砂含量高于黄厝、南线十八线和小嶝岛潮下带的黏土和粉砂含量。2016年夏季黄厝、南线十八线潮下带黏土和粉砂含量明显高于2014年夏季的黏土和粉砂含量。相关分析表明,5个大型底栖动物群落参数如物种数、栖息密度、生物量、多样性指数(H′)和丰度指数(d), 7个常见种的栖息密度和生物量与粉砂和黏土含量呈显著正相关,均匀度指数(J)和4种常见种的数量与粉砂和黏土含量无显著相关,白氏文昌鱼(Branchiostoma belcheri)的栖息密度和生物量与粉砂和黏土含量呈显著负相关。上述结果证实,黏土含量增加到15%和粉砂含量增加到60%有利于多数大型底栖动物栖息密度和生物量的增加,但导致白氏文昌鱼栖息密度和生物量的减少,而红角沙蚕(Ceratonereiserythraeenis)、滑指矶沙蚕(Eunice indica)、光滑倍棘蛇尾(Amphioplus laevis)受底质细化的影响较小。 相似文献
2.
渤海大型底栖动物种类组成与群落结构研究 总被引：1，自引：1，他引：0
本文利用2008年8月在渤海23个站位采集的样品对大型底栖动物的丰度、生物量、群落结构及其与环境因子的关系进行了研究。共鉴定出大型底栖动物300种,主要类群包括环节动物多毛类、节肢动物甲壳类、软体动物、棘皮动物等。研究海域大型底栖动物的平均丰度为1 094.7ind/m2,平均生物量为11.78g/m2,其中丰度最高区位于辽东湾,最低区位于渤海湾;生物量最高区位于渤海中部,最低区出现在渤海海峡湾口处。依据丰度和生物量进行了CLUSTER聚类和MDS标序图分析,结果可将研究站位划分为6个站组,均与沉积物底质类型密切相关。所研究海域底质类型包括黏土质粉砂、砂、砂质粉砂、粉砂质砂、砂-粉砂-黏土5种。通过BIOENV分析,发现影响大型底栖动物群落结构和分布的主要环境因子有水深、黏土粉砂含量、脱镁叶绿酸含量、叶绿素含量等。与20世纪90年代历史数据的对比发现,本次研究大型底栖动物的物种数目明显减少,平均丰度也减少,特别是优势物种表现出了小型化趋势,传统的大型种类,如心形海胆、双壳类等,被小个体的多毛类和甲壳类所取代。本研究表明渤海近年来受人类活动影响,出现了不同程度的污染,导致大型底栖动物群落结构发生了变化。 相似文献
3.
2012年9月对辽东湾西部倾倒区海域的大型底栖动物进行了调查。调查海域共发现底栖动物54种,包括多毛类35种,甲壳类10种,软体动物6种,棘皮动物1种,其他2种。底栖动物丰度平均为1 140.8个/m2,生物量为11.02 g/m2,多样性指数平均为3.39。丰度、生物量比较结果显示,调查海域大型底栖动物群落受到中度干扰,调查海域底栖动物群落可分为以对照组为主的群落和倾倒区群落。海洋倾倒导致倾倒区内大型底栖动物的种类数量、丰度、生物量和多样性水平下降,群落特征种受倾倒的影响较明显。底栖动物与重金属含量之间无显著相关关系,掩埋是辽东湾西部倾倒活动主要的影响方式。 相似文献
4.
2009-12对辽东湾西部海域进行5条断面15个站位的大型底栖动物调查。共鉴定出大型底栖动物69种,其中纽形动物1种,多毛类31种,软体动物11种,甲壳类25种,棘皮动物1种。优势种有长尾亮钩虾(Photis longicaudata)、日本浪漂水虱(Cirolana japonensis)和长吻沙蚕(Glycera chirori)等。调查海域大型底栖动物平均丰度为955个/m~2,平均生物量为14.0g/m~2。丰度和生物量分布整体呈现离河口越远越高的趋势。在25%相似度尺度上,该海域大型底栖动物可划分为4个群落,各群落受到不同程度扰动。检验得出,底层水环境因子不足以影响大型底栖动物群落结构。 相似文献
5.
西门岛红树林区大型底栖动物的群落结构 总被引：20，自引：0，他引：20
浙南乐清湾西门岛红树林区是中国红树林的最北分布地,为研究该区红树林与底栖动物的生态关系,于2004年5月和8月对红树林区大型底栖动物进行现场采样,共发现大型底栖动物42种,其中软体动物20种、甲壳类11种、多毛类5种、其它类6种。平均生物量和平均栖息密度分别为74.26g/m2和340个/m2,软体动物和其它类动物分别占总生物量的43%和39%,它们的栖息密度分别占动物总栖息密度的66%和30%。红树林区底栖动物的特征种为可口革囊星虫Phascolosomaesculenta,在中潮区其生物量和栖息密度分别高达84.33g/m2和304个/m2。该红树林区底栖动物群落结构的分析结果表明:底栖动物种类与红树林发育状况呈负相关、底栖动物生物量与红树林发育状况呈正相关,红树林主分布区(中潮区)底内群落结构较低潮区简单、生物量高、物种多样性低,而无红树林的低潮区则与之相反,生物量低、种间分布均匀、多样性高。多样性指数低潮区(2.44)>中潮区(1.21)>高潮区(1.0);均匀度指数为0.30～0.73,中潮区为最低。 相似文献
6.
《海洋湖沼通报》2016,(3)
2013年5月对浙江省温州市瓯江口和飞云江口附近海域7个海岛的7条潮间带断面进行了大型底栖动物群落结构调查。共鉴定出大型底栖动物120种,其中软体动物44种,甲壳类33种,多毛类31种,腔肠动物6种,其它动物6种。优势种东方小藤壶(Chthamalus challengeri)是北方海域的典型优势种,首次在调查海域乃至浙南海域占据优势地位。潮间带大型底栖动物的平均生物量和平均栖息密度分别为539.14g/m2和4945个/m2。各断面的Shannon-Wiener(H′)多样性指数、Margalef丰富度指数(d)和Pielou evenness均匀度指数(J)分别为0.496-2.720、1.946-4.071和0.117-0.508,平均值分别是1.923、2.756和0.403。灵昆泥相潮间带的ABC曲线表明该断面大型底栖动物受到严重的扰动。岩相潮间带数据与历史数据比较发现大型底栖动物趋向小型化,机会种逐渐取代敏感种的优势地位,生态系统功能呈现退化趋势。 相似文献
7.
2013—2014年在大连凌水湾海域进行了大型底栖动物月份调查。调查共采得大型底栖动物54种,包括环节动物门26种、软体动物门12种、节肢动物门类8种、棘皮动物门2种、纽形动物门1种、腔肠动物门2种、腕足动物1种。其中多毛类种类最多,共26种,占总种数的48.1%;其次是软体动物门12种,占总种数的22.2%;再次是甲壳类8种,占总种数的14.8%。除去个别大密度和大个体生物影响,2013—2014年大型底栖动物种类、栖息密度以及生物量,都呈现上升趋势,由多样性指数、优势度、均匀度、健康度等指数所表示的群落结构生态学特征显示,大型底栖动物群落结构较健康。 相似文献
8.
海州湾潮间带大型底栖动物的分布特征 总被引：2，自引：0，他引：2
于2002年6月对海州湾3种底质的潮间带底栖动物进行了采样分析.结果显示,该区被鉴定出的大型底栖动物共有98种,其中多毛类为13种、软体动物为53种、甲壳类为25种、棘皮动物为2种、其它类动物为5种,软体动物和甲壳类的种类可占80%;该区潮间带大型底栖动物的平均生物量和平均栖息密度分别为257.30 g/m2和953个/m2,软体动物生物量(201.19 g/m2)和栖息密度(727 个/m2)分别占总数的78%和76%.经底栖动物种类相似性聚类分析和多维尺度排序,可将该区潮间带大型底栖动物划分为岩礁、沙滩和泥沙滩3个群落.通过对3个底栖动物群落的生态特征及相关环境因子分析得出:对于种类,泥沙滩群落 > 岩礁群落 > 沙滩群落;对于生物量、息栖密度、多样性指数和均匀度指数,岩礁群落 > 泥沙滩群落 > 沙滩群落;泥沙滩群落中的TE断面优势种分布显著而使多样性指数和均匀度指数明显低于其它两条泥沙滩断面.沙滩群落和岩礁群落的底栖动物分布分别与海水浴场和货运码头较多的人为活动影响有关,而泥沙滩群落的分布差异主要与海岸开敞度、海流潮汐作用、滩涂贝类养殖及优势种分布影响有关.泥沙滩是该区经济贝类的重要养殖场所,为使养殖种类健康生长,建议对沿岸排污口水质及养殖区沉积物环境质量进行定期监测. 相似文献
9.
为了解洞头列岛及邻近海域大型底栖动物的群落结构特征,于2015年4月在该海域布设35个站位进行大型底栖动物调查采样,并获取相关环境资料,分析了该海域大型底栖动物的群落结构及其与环境因子的关系。共鉴定出大型底栖动物122种,其中多毛类57种,甲壳动物34种,软体动物19种,棘皮动物5种,其它类动物7种。各调查站位大型底栖动物物种数目在1~22种之间,瓯江口附近站位物种数较少。大型底栖动物平均生物量为3.35 g/m2,平均栖息密度为321个/m2。多毛类具有种数上的优势,软体动物具有生物量和密度上的优势。Shannon-Wiener多样性指数、Margalef丰富度指数和Pielou均匀度指数的平均值分别为1.29、2.45和0.66。通过聚类分析和多维尺度排序分析将该海域大型底栖动物划分为3个群落:异蚓虫-薄云母蛤-绒毛细足蟹-不倒翁虫群落(群落Ⅰ),薄云母蛤-异蚓虫-双鳃内卷齿蚕-不倒翁虫群落(群落Ⅱ)和其他群落(群落Ⅲ)。典范对应分析表明,影响大型底栖动物群落的主要环境因子有底层海水的温度、盐度、活性磷酸盐、活性硅酸盐、溶解性无机氮、化学需氧量以及表层沉积物中的总有机碳等。ABC曲线分析结果表明,大型底栖动物群落受到了一定程度的扰动,但基本稳定。与历史资料相比,大型底栖动物的栖息密度和生物量均无明显变化,种类组成由以多毛类和软体动物为主转变为以多毛类和甲壳动物为主,且个体较大的棒锥螺大量死亡。 相似文献
10.
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
14.
15.
《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
17.
18.
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
19.
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
20.
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