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对多齿围沙蚕(Perinereis nuntia Savigny)亲体的培养条件进行了研究.结果表明:多齿围沙蚕的适宜培养温度为16～32℃,盐度为25～32.培养时以粉末饵料为佳,16～32℃摄食活泼,摄食时间为15～20min,16℃以下摄食量减少,12℃以下基本不摄食.在19～20℃、保持潮湿条件下,可存活28 d.异沙蚕体形成与温度有关,特别是在经历了一定的低温期(2～4℃)后,再提高温度至18～25℃,可以有效地促进异沙蚕体形成.在人工养殖情况下,异沙蚕体的形成及群浮并未出现半月相型规律,成熟后只要有微弱的光照,任何时间加水覆盖水槽均可见到异沙蚕体群浮. 相似文献
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通过生态学及组织学方法对人工养殖条件下多齿围沙蚕(Perinereis nuntia Savigny)亲体培育条件及繁殖生物学进行了研究.结果表明,多齿围沙蚕雌雄异体,非成熟季节外观上无法辨别雌雄,性成熟时,雌(异沙蚕体)灰绿色,雄(异沙蚕体)红白色.生殖细胞起源于体腔膜上皮,不久就释放到体腔中,在体腔内卵原细胞和精原细胞http://ebook/成都,今夜请将我遗忘/index.htm分裂增殖形成卵原细胞群和精原细胞群,体腔中充满了外形不规则或近圆形的滋养细胞,细胞内可见嗜伊红颗粒,滋养细胞之间可见发达的微血管.卵原细胞群不断增殖发育,至初级卵母细胞后游离至体腔中继续发育为次级卵母细胞和成熟卵子;精原细胞群形成精子合胞体(syncytium),各级精母细胞在合胞体内发育,直至形成成熟精子时才分散游离.水温18℃以上,多齿围沙蚕的生长体经培育才可能形成异沙蚕体.特别是在经历了一定的低温期后,再提高温度可以有效的促进异沙蚕体形成.胚胎发育的适宜温度为18～25℃;适宜盐度为25～32.胚胎发育过程经历卵裂期、囊胚期、原肠期、担轮幼虫期、后担轮幼虫期、膜内游毛幼虫期等阶段,在水温25℃、盐度30条件下,从受精至孵出3刚节幼虫约需65 h.3刚节游毛幼虫至10刚节幼体约需28 d. 相似文献
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双齿围沙蚕对潮汐更替的行为响应 总被引：1，自引：0，他引：1
潮汐更替对潮间带生物的生理和行为影响显著,底内动物可以通过行为过程建立适宜的微环境适应潮间带环境变化。本实验运用行为学观测装置研究了双齿围沙蚕对潮汐更替的行为响应特征。实验设置3个温度梯度（15℃、20℃和25℃）和4个时间段（T1: 退潮前、T2: 退潮后、T3: 涨潮30 min内和T4: 涨潮30 min后）,每个处理组设6个重复。结果显示,在同一时间段内,随着温度的升高,双齿围沙蚕的径向起伏频率、径向起伏泵水速率、轴向爬行速度和头尾对调次数呈增大的趋势,头尾对调一次的时间逐渐缩短。同一温度下,双齿围沙蚕在T3时间段内的径向起伏频率、轴向爬行速度、径向起伏泵水速率、径向起伏泵水效率、轴向爬行时间和头尾对调次数均高于其他时间段,头尾对调一次的时间均有短于其他时间段的趋势;T1和T4时间段内的所有运动指标均无显著差异（p>0.05）。20℃时,双齿围沙蚕在T3时间段比T1时间段的径向起伏频率和泵水速率的增幅均高于15℃和25℃时。同一时间段内,双齿围沙蚕径向起伏时间的最大值和轴向爬行时间的最小值均出现在20℃。15℃和20℃时,双齿围沙蚕在T1和T3时间段内的轴向爬行速度均无显著差异（p>0.05）。但是在25℃时,T3时间段内双齿围沙蚕的轴向爬行速度显著高于T1时间段（p<0.05）。结果表明,双齿围沙蚕的运动强度随温度升高而增强,在水温为20℃时,其在沉积物中的运动状态较佳。退潮后双齿围沙蚕轴向爬行运动较为缓慢;刚涨潮时,双齿围沙蚕的运动强度显著增加;涨潮30 min后,双齿围沙蚕的运动逐渐恢复到与退潮前相近的状态。双齿围沙蚕可以通过一系列运动行为应对潮汐更替产生的不利条件。 相似文献
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日本刺沙蚕的性信息素研究 总被引：2，自引：0，他引：2
日本刺沙蚕（Ｎｅｒｅｉｓ ｊａｐｏｎｉｃａ）广泛分布于中国沿海，是鱼、虾的优良饵料，冬末春初敏殖时离开河口向盐较高的海区移动。与多齿围沙蚕，褐片阔沙蚕等其它沙蚕不同，日本刺沙蚕在繁殖过程中不出现完全变态，但是与其它沙蚕一样，其繁殖过程也受一组性信息素控制。从雌性熟的日本刺沙蚕体腔液中提取并鉴定出一种有生物活性的挥发性物质－辛二烯－［３，５］－酮－［２］，这种化合物可以增加群浮个体在配子释放之前婚舞 相似文献
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日本刺沙蚕（Ｎｅｒｅｉｓｊａｐｏｎｉｃａ）广泛分布于中国沿海，是鱼、虾的优良饵料，冬末春初繁殖时离开河口向盐度较高的海区移动。与多齿围沙蚕，褐片阔沙蚕等其它沙蚕不同，日本刺沙蚕在繁殖过程中不出现完全变态，但是与其它沙蚕一样，其繁殖过程也受一组性信息素控制。从雌性成熟的日本刺沙蚕体腔液中提取并鉴定出一种有生物活性的挥发性物质──辛二烯－［３，５］－酮－［２］，这种化合物可以增加群浮个体在配子释放之前婚舞时的游动速度．但不诱导配子释放。在许多沙蚕中有着性信息素作用的５－甲基－３－庚酮，在日本刺沙蚕体腔液中没有发现，也没有性信息素作用。 相似文献
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双齿围沙蚕对温度、盐度和干露的耐受性研究 总被引：1，自引：0，他引：1
本论文主要研究双齿围沙蚕(Perinereis aibuhitensis)对盐度突变、温度突变和盐度渐变、温度渐变及干露的耐受性。实验结果表明:双齿围沙蚕耐受盐度的范围比较广泛,为5~45,适宜的盐度范围为20~30,求得双齿围沙蚕96 h半致死盐度上限为33.1。适宜温度范围为20~30℃,对低温有很强的耐受力。双齿围沙蚕在低温保湿干露10 d未发生死亡,大量死亡集中在13~14 d。本研究结果表明:双齿围沙蚕对环境的适应性较强,耐温、耐盐范围较广,且具有很强的耐干露能力。 相似文献
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沙蚕科性信息素的种间作用 总被引：2，自引：0，他引：2
本文对海洋多毛类沙蚕科4属7种沙蚕:褐片阔沙蚕(Platynereis dumerilii)、双管阔沙蚕(P.bicanaliculata)、日本刺沙蚕(Neanthes japonica)、琥珀刺沙蚕(N.succinea)、多齿围沙蚕(Perinereis nuntia)、绿沙蚕(Nereis virens)和涂沙蚕(N.fucata)性信息素的种间作用进行了电生理和行为反应的研究.结果表明,同属的双管阔沙蚕和褐片阔沙蚕及日本刺沙蚕和琥珀刺沙蚕的异沙蚕体的体腔液可以互相诱导异性的异沙蚕体发生婚舞(naptial dance)和释放配子;雌性或雄性的多齿围沙蚕、雄性的绿沙蚕和涂沙蚕的异沙蚕体体腔液分别可以诱导异性褐片阔沙蚕异沙蚕体发生婚舞并释放配子;但雌性或雄性褐片阔沙蚕、雄性的日本利沙蚕、琥珀刺沙蚕和涂沙蚕的异沙蚕体的体腔液却不能诱导异性多齿围沙的异沙蚕体发生婚舞或释放配子.不过,雌性褐片阔沙蚕异沙蚕体的体腔液能引起雄性多齿围沙蚕异沙蚕体脑电活性的增强. 相似文献
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本文对福建近海天然与养殖的双齿围沙蚕(Perinereis aibuhitensis)进行基本成分、氨基酸、脂肪酸、矿物元素以及沙蚕毒素进行测定.结果表明,不论是天然或是养殖的,双齿围沙蚕均富含粗蛋白质(60%,干基)和氨基酸(TAA∶54.27%~56.80%);必需氨基酸(EAA/TAA约37%,EAA/NEAA≥0.58)基本符合联合国粮农组织(FAO)、世界卫生组织(WHO)推荐的理想蛋白模式;呈味氨基酸所占的比例(FAA/TAA约45%)也较高.其油脂含量为9.9%~12.5%,且脂肪酸中富含n-3 PUFAs.双齿围沙蚕体所含的必需矿物元素种类齐全,Fe、Zn、I、Se等含量丰富;而有毒元素(Pb、Hg、Cd、总As与无机砷)的含量却较其它海洋水产动物低.沙蚕毒素的分析结果表明,新鲜的双齿围沙蚕均含有沙蚕毒素(1.68~2.42 mg/kg),而经80℃以上烘干或煮熟后的NTX为未检出.因此,不论是天然的还是养殖的双齿围沙蚕均属于高蛋白质,且富含n-3 PUFAs和微量必需. 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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Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
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
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G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
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
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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
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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
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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,(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