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1.
于1987年及1988年冬季在长江,珠江,湖北武汉东湖、保安湖、洪湖、武黄湖,安徽太平湖,广东仙溪水库采集了草鱼、团头鲂和长春鳊,共328尾,测定了鱼体生化成分。结果表明:1.在同一水域、同一季节收集三种鱼的系列样品,鱼体的水分、蛋白质、脂肪的含量和能值与鱼体重关系显著,三种鱼体的灰分和无氮浸出物的含量与体重无明显关系;2.不同水域的三种鱼,湖泊鱼体的含脂量、能值、能量与蛋白质的比值均高于江中的同种、同龄体长接近的鱼,水分含量则低于江中的鱼,蛋白质、灰分和无氮浸出物差异不大;3.三种鱼的蛋白质均含有常见的17种氨基酸。  相似文献   

2.
李军 《海洋科学集刊》1997,(38):155-161
生物体的含能量及比能值(Q,指单位体重的含能量)是能量学研究的重要参数,蛋白质、脂肪和碳水化合物是生物体含能量的主要物质载体。在鱼体中,碳水化合物的含量约占0.5%,在鱼类能量学研究中一般忽略不计,生化组分决定鱼体的能量含量。在自然界中,鱼体的生化组成是变化的(Craig,1977),精确估计鱼体的含能量及生化组成是建立鱼类能量收支方程的必要条件,但同时也是深入开展能量学研究的主要困难之一。研究者发现,在各种条件下,鱼体各组分之间都有比较恒定的比例关系( Elliott,1976; Weatherly et al,1983),因此提出,如果以鱼体某个易于测定的指标(如含水量、体重等)作为自变量,建立起与含能量及化学组成较显著的相关关系,则可较方便地对有关指标进行间接估计。 1994年8-11月,作者在对黑鲷(Sparus macrocephalus B.,)进行能量学研究的同时,对其比能值及化学组成亦进行了测定,探讨了日粮水平(RI)对鱼体比能值及生化组成的影响,建立了干物质含量和比能值的预测模式以及含水量与比能值、蛋白质含量、脂肪含量的回归关系,以便对实验鱼类的比能值及化学组成进行间接估计。  相似文献   

3.
测定了中国团扇鳐和林氏团扇鳐肌肉中的水分含量、灰分含量及能值.中国团扇鳐肌肉水分含量为75.86%,灰分含量为5.15%,能值为21.49MJ/kg;林氏团扇鳐肌肉水分含量为76.66%,灰分含量为5.04%,能值为21.29MJ/kg.中国团扇鳐、林氏团扇鳐的体重与体长有显著的正相关关系;中国团扇鳐、林氏团扇鳐的水分含量随体重的增加而减小,能值随体重的增加而升高;中国团扇鳐肌肉的能值与水分含量之间具有一定的相关递减的趋势,林氏团扇鳐水分含量与灰分含量之间具有一定的相关递增的趋势.此外,中国团扇鳐、林氏团扇水分含量、灰分含量及能值随季节的变化而变化.这与鱼体自身的生物学特性有关。也受到环境因子变化的影响.  相似文献   

4.
眼斑拟石首鱼生长特性的初步研究   总被引:6,自引:0,他引:6  
王波  毛兴华 《海洋通报》1997,16(5):36-42
本文研究了眼斑拟石首鱼生长的特性以及外界因素对共生长的影响。未成熟鱼体重与体长关系为W=0.0123SL^3.0511,成熟鱼其关系为W=0.0042SL^3.2422;此鱼幼鱼全长与体长呈直线关系TL=1.1506SL+0.2866。在适宜的温度条件下鱼的生长快速,平均最大生长率达4.88g/d。在海水养殖中起鱼死亡的临界DO值为2.0mg/km^3左右。我国北方养殖一年鱼的体重可达500g,南  相似文献   

5.
肌肉生长抑制素(MSTN)基因对肌肉生长起负调控作用,在动物育种上具有潜在的应用前景.报道了眼斑拟石首鱼(Sciaenops ocellatus)的MSTN基因的序列结构特征及其组织特异性表达.MSTN基因具有3个外显子和2个内含子,编码376个氨基酸.在内含子Ⅰ和3'-UTR区内,分别发现了(TC)4CC(TC)4CT(TC)4和(AC)7微卫星序列.推断的眼斑拟石首鱼的MSTN氨基酸序列具很强的保守性,与石鼓鱼、金鲷、条纹石鮨、白鲈、金眼石鮨之间的相似性在90%以上.在结构上,眼斑拟石首鱼的MSTN包含N端信号序列(1~22氨基酸残基),TGF-β前肽域(41~256氨基酸残基),RXXR蛋白水解位点(264~267位的RARR)和TGF-β区域(282~376氨基酸残基).在检测的10种组织中,MSTN只在眼斑拟石首鱼的肌肉、脑和眼组织中表达,其中在肌肉表达最强.  相似文献   

6.
不同体重异育银鲫(Carassius auratus gibelio)的补偿生长   总被引:9,自引:0,他引:9  
在实验室内进行了8周实验以确定不同体重的异育银鲫的补偿生长。按初始体重将实验鱼分为L[(8·7±0·0)g]、M[(5·3±0·1)g]和S[(3·2±0·0)g]三个规格,每个规格的鱼或在第1—2周停食,在第3—8周按饱食投喂(停食鱼)或始终按饱食投喂(对照鱼)。结果表明,第2周结束时,停食鱼体重、全鱼脂肪与蛋白质含量明显低于同规格的对照鱼,而全鱼灰分和水分含量高于后者。第3—8周内停食鱼摄食率和特定生长率(SGR)明显高于同规格对照鱼,但饲料效率与后者无明显差异。第8周结束时,停食的M鱼体重与同规格对照鱼无显著差异,停食的L和S鱼体重仍明显小于同规格对照鱼,表明恢复投喂后停食的M鱼实现完全补偿,而L和S鱼为部分补偿。实验结束时停食的M鱼全鱼组成与同规格对照鱼无明显差异,但鱼躯干蛋白质含量和内脏团脂肪含量仍明显低于后者,内脏团蛋白质和灰分含量高于后者;停食的L鱼躯干鱼体组成与同规格的对照鱼无显著差异,但全鱼脂肪和蛋白质含量、内脏团脂肪含量仍明显低于后者;绝食的S鱼内脏团组成与同规格的对照鱼无显著差异,但全鱼脂肪含量以及鱼躯干脂肪和蛋白质含量明显低于后者。  相似文献   

7.
黄斑蓝子鱼幼鱼对蛋白质和脂肪适宜需要量的研究   总被引:3,自引:0,他引:3  
采用酪蛋白为蛋白源、鱼油为脂肪源,配制脂肪含量为8%而蛋白水平分别为24%、28%、32%、36%和40%,以及蛋白含量为32%而脂肪水平分别为3%、6%、9%和12%的9种配合饲料,对黄斑蓝子鱼(Siganus canaliculatus)幼鱼开展8周的生长试验,以研究其对蛋白质和脂肪的适宜需要量。结果显示,饲料中的蛋白质和脂肪含量对蓝子鱼的生长性能、饲料利用率及鱼体生化成分等都有一定的影响。蛋白水平过高(40%)或过低(24%)的饲料组鱼的生长效果较差;32%蛋白水平组鱼的增质量率和蛋白质效率最好、且显著高于其他各组,而饲料系数显著低于其他各组。鱼体的蛋白质含量随着饲料蛋白水平的增加而呈上升趋势,但水分、粗脂肪和灰分的含量不受影响。3%~9%脂肪水平组鱼的增质量率、饲料系数和蛋白质效率相互间无显著差异,但它们的增质量率及蛋白质效率显著高于12%脂肪水平组鱼,而饲料系数正好相反。肝体指数和鱼体脂肪含量随着饲料脂肪水平的增加而升高,但鱼体的蛋白质和水分含量受饲料脂肪水平的影响不大。3%脂肪水平组鱼的成活率较低。根据增质量率及蛋白质效率与饲料蛋白水平的二次回归分析,获得蓝子鱼幼鱼对蛋白质的适宜需要量为29.01%~34.37%;综合考虑上述指标,认为蓝子鱼幼鱼饲料中脂肪的适宜添加量为6%~9%。  相似文献   

8.
陈万青 《海洋世界》2009,(10):52-53
石首鱼是鲈行目,石首鱼科鱼类的统称。石首鱼体稍长,侧扁,口大。头骨具粘液腔,体被栉鳞。耳石很大,因而得名“石首”。鳔发达,多数石首鱼可通过鳔上肌肉的活动发出声音,鲽起到共鸣室的作用。石首鱼是底栖、肉食性鱼类,主要以软体动物为食。  相似文献   

9.
眼斑拟石首鱼的营养需求及环境因子对生长的影响   总被引:3,自引:1,他引:3  
王波  孙红英 《海洋通报》1996,15(6):82-87
综述发眼斑拟石首鱼对饵料营养的需求量,以及环境因子如水浊,盐度,溶解氧,氮化物,总硬度,氯化物等对其生长,生存的影响。  相似文献   

10.
美国红鱼海上网箱养殖技术研究   总被引:3,自引:0,他引:3  
美国红鱼属鲈形目,石首鱼科,拟石首鱼属,学名为Sciaenopsocellatus,中文直译名为眼斑拟石首鱼,在台湾等地又称红鱼、红姑鱼、斑尾鲈、黑斑红鲈等。体型与鮸鱼、大黄鱼近似,体色微红,尾鳍基部通常有1~4个黑色圆斑。美国红鱼原产墨西哥湾及美国西南部沿岸,是美国重要的商业养殖鱼类。1991年国家海洋局第一海洋研究所从美国引进该鱼的仔鱼进行入工养殖,对其在我国的生态、生长特性、养殖技术做了初步研究,并于1995年成功地培育出了第一代美国红鱼鱼苗[1~5]。美国红鱼具有生长快、适温广,能在海水…  相似文献   

11.
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.  相似文献   

12.
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   

13.
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   

14.
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   

15.
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   

16.
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.  相似文献   

17.
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   

18.
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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