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细基江蓠及其繁枝变种的RAPD和ITS分析 总被引：4，自引：2，他引：4
对细基江蓠及其繁枝变种各12个个体进行随机扩增多态性(RAPD)DNA分析,对比多态位点比例、平均杂合度以及遗传距离,并构建UPGMA聚类图;通过PCR扩增出核糖体RNA基因(rDNA)转录间隔区(ITS),纯化后直接测序,利用生物信息学方法进行序列分析和核苷酸变异研究.比较分析结果表明,细基江蓠的杂合度和多态位点比例均高于细基江蓠繁枝变种,其遗传多样性相对较丰富;实验中8条随机引物扩增出特异的RAPD带,可用做细基江蓠及其繁枝变种的分子鉴定标记;ITS序列在这两种海藻中变异极小;RAPD和ITS聚类分析研究结果表明,细基江蓠及其繁枝变种均聚集为一枝,与同属不同种的龙须菜和真江蓠分开,提示细基江蓠和及其繁枝变种为同一个种,从而在DNA水平上支持了传统形态分类的观点. 相似文献
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细基江蓠繁枝变种和细基江蓠营养成分的比较研究 总被引：4，自引：0，他引：4
近年来 ,随着我国南方九孔鲍养殖业的发展 ,细基江蓠繁枝变种 (Ｇｒａｃｉｌａｒｉａｔｅｎｕｉｓｔｉｐｉｔａｔａｖａｒ．Ｌｉｕｉ)的人工栽培在我国东南、华南沿海地区蓬勃兴起 ;为此作者于１９９９年元月在广东、海南、广西采集细基江蓠繁枝变种和细基江蓠 (Ｇｒａｃｉｌａｒｉａｔｅｎｕｉｓｔｉｐｉｔａｔａ) ,应用ＨＰＬＣ、原子吸收等分析手段 ,测定其营养成分（主要包括蛋白质、氨基酸、脂肪、粗纤维、灰分、矿物质及微量元素等） ,并与其他几种大型藻类比较 ,综合评价细基江蓠和细基江蓠繁枝变种的营养价值。１材料与方法１．１材… 相似文献
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温度和盐度对几种大型海藻生长率和NH4-N吸收的影响 总被引：19，自引：3，他引：19
温度和盐度对细基江蓠繁枝变型(Gracilaria tenuistipitata var.liui)、孔石莼(Ulva pertusa)和蜈蚣藻(Grateloupia filicina)生长率及细基江蓠繁枝变型NH4-N吸收的影响进行了实验研究.结果表明,温度和盐度对上述3种海藻生长率及NH4-N吸收均有显著影响.3种海藻的生长适宜温度和盐度范围分别为细基江蓠繁枝变型20～30℃,15～30,孔石莼15～25℃,15～40,蜈蚣藻20～25℃,25～35;最大日特定生长率(SGR)分别为8.66%,12.28%,2.24%;N饥饿细基江蓠繁枝变型对NH4-N的吸收存在短期的快吸收.细基江蓠繁枝变型NH4-N吸收的最适温度和盐度范围分别为15～25℃,10～25.生长率及NH4-N吸收速率与温度和盐度之间分别存在以下关系:SGRG.t.=0.873(S-5.487)(T-9.007)e(-0.0708S-0.0745T);SGRU.p.=0.222(S-2.665)e-0.047S(T-9.98)e-0.00057(T-9.98)2.7;SGRG.f.=2.6×10-4(S-10.856)(T-11.704)e0.156T-3.36×10-6STe0.219T;Vupt=11.812(S-4.081)(T-9.221)e-0.1S-0.148T. 相似文献
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在2011~2013年间对粤东地区进行了20余次野外大型海藻资源调查,采集了大量标本。利用形态特征,对部分标本进行了分类学研究。经鉴定,标本中包含江蓠属5个种及变种,即芋根江蓠Gracilaria blodgettii Harvey、异枝江蓠G.bailinae Chang et Xia、细基江蓠G.tenuistipitata Chang et Xia、细基江蓠繁枝变种G.tenuistipitata var.liui Zhang et Xia、长喙江蓠G.longirostris Zhang et Wang。它们的主要鉴定特征分别为:芋根江蓠的分枝基部明显缢缩;异枝江蓠的藻体暗绿色,初级分枝围绕主轴互生、偏生或叉分;细基江蓠的藻体主轴基部纤细,分枝简单;细基江蓠繁枝变种的藻体纤细,分枝繁多;长喙江蓠的囊果具有明显的长喙状突起。其中,芋根江蓠和异枝江蓠在粤东地区属首次报道,文章对其进行了较详细的介绍。该研究结果丰富了粤东江蓠属的物种多样性,为粤东地区江蓠属物种资源的保护和利用提供了分类学依据。 相似文献
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我国的江蓠约有２０多种。已深入研究过的有：真江蓠、细基江蓠、龙须菜、芋根江蓠、海南江蓠、节江蓠、绳江蓠、缢江蓠、凤尾菜和扁江蓠等［１－３］。近年来，在我国养殖数量最大的一种是细基江蓠繁枝变型（Ｇｒａｃｉｌａｒｉａｔｅｎｕｉｓｔｉｐｉｔａｔａ（ＣｈａｎｇｅｔＸｉａｆ．ＬｉｕｉＺｈａｎｇｅｔＸｉａ）。该种江蓠比较容易养，故在海南、广东和广西沿海地区养殖较多，成为目前南方琼胶厂使用较多的一种原料。但对这种江蓠所含琼胶的性质和组成尚未研究过，故笔者对此进行了全面的研究。１材料与方法１．１材料细基江蓠繁枝… 相似文献
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以海水工厂化养殖排出的废水养殖双齿围沙蚕(Perinereis aibuhitensis)、菲律宾蛤仔(Ruditapes phi-lippinarum)、长牡蛎(Crassostreagigas)和细基江蓠(Gracilariatenuistipitata).结果表明:双齿围沙蚕耐污染能力最强;细基江蓠和双齿围沙蚕具有较强的净化水质能力.养殖废水经7 d处理后,NH4+-N、NoO3--N、NO2--N、PO43--P、COD和底质有机物分别下降至处理前的11.20%、23.69%、27.50%、14.6%、3.2%和0.32%,且沙蚕和江蓠平均日生长率分别为2.30 mg/g·d和80 mg/g·d.该方法不但能净化水质,还能实现养殖废水的循环利用. 相似文献
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通过静态模拟实验,比较研究了6个硝态氮(NO3--N)摩尔浓度水平(0,10,20,40,60,80μmol/L)下培养的细基江蓠繁枝变型(Gracilariatenuistipitatavar.liuiZhangetXia)的丙二醛(MDA)、游离脯氨酸含量以及硝酸还原酶(NR)、超氧化物酶歧化酶(SOD)、过氧化物酶(POD)活性的变化。结果表明,随着水体NO3--N摩尔浓度的逐渐增加,细基江蓠繁枝变型NR、SOD和POD的活性均呈现先增加后下降的显著变化(P<0.05),膜脂过氧化产物MDA含量随水体NO3--N摩尔浓度的变化则呈相反的趋势(P<0.05);游离脯氨酸含量则与水体NO3--N摩尔浓度呈正相关(r=0.9161)。综合分析结果认为,单独以硝态氮为氮源时,20μmol/L的供氮水平能使细基江蓠繁枝变型处于相对最佳的生理状态。 相似文献
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光照和温度对细基江蓠繁枝变型的生长及生化组成影响 总被引：3，自引：1，他引：3
实验研究光照、温度对细基江蓠的生长率及生化组成等指标的影响。结果表明 ,光照、温度及其相互作用均显著影响以上指标。在该实验条件下 ( 15～ 30℃ ,12 0 0～ 12 0 0 0 lx) ,细基江蓠繁枝变型 ( Gracilaria tenuistipitata var.liui)在光照为 10 0 0 0 lx,温度为 2 5℃时生长率最大 ,光照对生长的影响大于温度 ,而且在适宜的温度范围内 ,随着温度的升高 ,细基江蓠繁枝变型生长的光饱和点也增高。光强是影响藻红素、叶绿素 a及碳水化合物 /蛋白质比率的主要环境因子 ,它与藻红素、叶绿素 a含量负相关 ,与碳水化合物 /蛋白质比率正相关。温度则是调节蛋白质及藻红素 /叶绿素 a比率的主要因素 ,它与蛋白质的含量负相关 ,与藻红素 /叶绿素 a比值正相关。温度和光照对碳水化合物的含量影响不明显 相似文献
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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
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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
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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
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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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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
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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
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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