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1.
研究了不同饵料种类(小沙丁鱼肉-NSF,鳗鱼配合饲料-CEFF,海水鱼配合饲料-CMFF)和摄食水平(从饥饿至饱食)对军曹鱼 Rachycentron canadum 幼鱼(平均初始体重约28g)生长和氮收支的影响,并建立了不同饵料种类时的生长-摄食关系和氮排泄-摄食关系.结果表明,投喂3种不同饵料的军曹鱼幼鱼湿重、干重和氮特定生长率均随摄食水平的增加呈显著增长趋势,其中,投喂NSF和CEFF组的特定生长率与摄食水平之间表现为减速增长曲线,投喂CMFF组的表现为直线;饱食时,投喂NSF和CEFF组的特定生长率接近而明显高于投喂CMFF组.投喂NSF和CEFF组的食物转化效率随摄食水平的增加而增长或呈先增长后下降的趋势,在饱食或次饱食(约为饱食量的70%)摄食水平组有最大值,而投喂CMFF组的食物转化效率随摄食水平的增加而持续增长,在饱食摄食水平时有最大值;除食物湿重转化效率外,投喂NSF组的食物转化效率最高,其次为投喂CEFF组,而两者均明显高于投喂CMFF组.3个饵料组的军曹鱼幼鱼摄食氮、排粪氮、生长氮和排泄氮均随摄食水平的增加呈显著增长趋势;投喂NSF和CEFF组的摄食氮、生长氮和排泄氮明显高于投喂CMFF组,而投喂CMFF组的排粪氮最高,其次为投喂CEFF组,且两者明显高于投喂NSF组.军曹鱼幼鱼投喂NSF、CEFF和CMFF时饱食和次饱食摄食水平的氮收支方程分别为:100CN=1.1(0.9)FN+27.0(29.3)GN+71.9(69.8)UN、100CN=5.2(4.3)FN+27.0(28.7)GN+67.8(67.0)UN和100CN=9.9(8.4)FN+21.6(10.1)GN+68.5(81.5)UN(氮收支方程括号中的为次饱食数据);3个饵料组军曹鱼幼鱼饱时和次饱食时摄食氮中用于排粪的比例较小且变化不大,投喂NSF和CEFF组次饱食时摄食氮中用于生长的比例较饱食时略大而用于排泄的比例较饱食时略小,但投喂CMFF组饱食时摄食氮中用于生长的比例明显高于而用于排泄的比例明显低于次饱食摄食水平时.因此,军曹鱼幼鱼的氮排泄和氮收支方程受摄食水平和饵料种类双重因素的影响,但不管投喂何种饵料,摄食氮增大是导致鱼类氮排泄增加的主要原因.综合考虑生长、食物转化效率、氮排泄和氮收支方程各因素,军曹鱼由幼鱼优先选择投喂的饵料为NSF,其次为CEFF,在本实验的生长阶段,两者的适宜投喂水平以占饱食量的70%-100%为佳. 相似文献
2.
报道用室内实验方法对鲢鱼摄食强度和摄食节律的研究结果,探讨了影响它们的因子。提出鲢鱼在不同水温、不同花粉密度及不同鱼规格下的摄食量的统计分析。指出:食粒密度和水温与摄食量正相关,而鱼规格与摄食量负相关;食粒密度对摄食量影响最大(P<0.01),其次为水温;水温和食粒密度在影响摄食量的过程中可能有一定的交互作用。鲢鱼摄食强度在室内条件下也具明显的昼夜节律。在食粒规格较小、密度较低且溶氧充足条件下,鲢鱼夜晚非但不停食且出现摄食率次高峰。在本实验条件下,鲢鱼的日摄食节律与水温和光照无关,可能受饵料可得性和自身的生物钟节律等制约。 相似文献
3.
漠斑牙鲆早期发育阶段的摄食与生长特性 总被引：1，自引：0，他引：1
2006年12月至2007年2月,在漳州市东山县华涛水产综合养殖场,采用生态学方法对人工培育的漠斑牙鲆仔、稚、幼鱼的摄食习性与生长特性进行了分析.结果表明,在水温为18.1～23℃时,仔鱼在孵出第6天开口摄食,开口饵料为褶皱臂尾轮虫(Bruchionus plicatilis),以后随着鱼体的生长,开始投喂卤虫无节幼体.对288尾仔、稚、幼鱼观察结果表明,其摄食率达83.0%,消化道饱满系数波动在0.9%～6.6%之间,日摄食指数在6.8%～29.6%;摄食具有明显的昼夜节律,一昼夜中仔鱼出现两个摄食高峰,分别出现在12:00和翌日08:00,稚鱼摄食高峰出现在10:00～14:00,幼鱼摄食高峰出现在12:00,但12:00～20:00均保持较高的摄食水平.仔、稚鱼夜间基本不摄食,幼鱼夜间有少量摄食.摄食量(y)与体重(W)的关系式为y=0.030 7W 0.050 5,全长(LT)与日龄(D)的关系式为LT=2.666 1e0.043 3D,体重(W)与日龄(D)的关系式为W=0.065e0.169 3D,全长(LT)与体重(W)的回归方程为W=0.001 8LT3.689 4. 相似文献
4.
军曹鱼人工育苗饵料投喂技术的初步研究 总被引：1，自引：0，他引：1
研究了军曹鱼Rachycentron canadum幼鱼(初始体重10g左右)的日摄食节律及不同摄食水平条件下鱼体的化学组成、特定生长率和食物转换率,以此确立人工育苗过程中军曹鱼幼鱼的适宜投饵时间和和投饵水平。研究结果表明,军曹鱼幼鱼具有明显的昼夜摄食节律,摄食主要在白天进行,以早晨(06:00—08:00)和傍晚(18:00—20:00)最为活跃,形成一天中的2个摄食高峰,夜间基本不摄食。由此可见军曹鱼幼鱼的摄食节律属白天摄食偏晨昏性类型。在饥饿、3%、6%、9%和饱食(指日投饵干重占试验鱼初始体重的百分比)摄食水平条件下,军曹鱼幼鱼鱼体蛋白质和脂肪含量随摄食水平的增加呈增长趋势,在6%摄食水平组脂肪含量出现大幅下降,在3%—饱食摄食水平时蛋白质含量变化不明显。军曹鱼幼鱼的湿重、干重和蛋白质特定生长率均随摄食水平的增加呈减速增长趋势,两者间的关系表现为对数函数形式:SGRw=3.876 ln(RL 1)-3.716,SGRd=5.107 ln(RL 1)-5.24,SGRp=5.561 ln(RL 1)-5.609,9%和饱食摄食水平组特定生长率无显著差异;脂肪特定生长率随摄食水平的增加而线性增长:SGRL=1.731RL-7.702。食物湿重、干重、蛋白质和脂肪转换率随摄食水平的增加均呈先升后降的变化趋势,9%摄食水平组有最大值,约为最大摄食水平的70%。因此,军曹鱼幼鱼投饵应在白天进行,适宜投饵时间为早晨和傍晚2个摄食高峰期,这个生长阶段的军曹鱼幼鱼当投喂鳗鱼配合饲料时其适宜投饵水平约为最大摄食水平的70%。 相似文献
5.
在人工培育条件下,采用实验生态学方法,对绿鳍马面鲀(Thamnaconus modestus)仔、稚、幼鱼生长、发育与摄食特性的变化进行了研究。结果表明,绿鳍马面鲀仔、稚、幼鱼的各生长指标可拟合为具有1~2个生长转折点的2~3段直线,其中全长、体长、体质量、肛前长、头长、吻长和体高可拟合为3段直线,眼径可拟合为2段直线。头长在第一转折点后的生长速率显著高于其他指标,除头长和体高在第二个生长转折点后生长速率减慢外,其余各项生长指标生长速度均逐渐加快。3~4日龄“开口期”前后的仔鱼,摄食发生率和饱食率均较低,随后逐渐升高。摄食发生率在12日龄后达到100%,饱食率在25日龄后达到100%(消化道充塞度为3~4级)。绿鳍马面鲀仔、稚、幼鱼均为白天摄食类型,白天摄食量占全天摄食量的71.6%以上。随日龄增长,鱼苗饱食时间呈下降趋势,消化时间则呈上升趋势。了解绿鳍马面鲀早期的生长发育与摄食特性,可为人工育苗管理提供参考,以促进鱼苗生长,提高成活率。 相似文献
6.
研究了不同摄食水平(从饥饿至饱食)和温度(21℃、27℃和33℃)对军曹鱼幼鱼(平均初始体重约10g)生长和氮收支的影响,并建立了生长-摄食/温度关系和不同摄食水平和温度条件下的氮收支方程。结果表明,在实验的温度范围内,军曹鱼幼鱼特定生长率均随摄食水平的增加呈显著增长趋势,生长-摄食关系在33℃时表现为线性相关,在27℃和21℃时表现为减速增长趋势,采用对数函数定量描述;在实验的摄食范围内(饥饿组除外),军曹鱼特定生长率随温度增加呈增长或先升后降的变化趋势,两者间的关系均采用二次函数定量描述。在实验的温度范围内,随摄食水平增加,军曹鱼幼鱼食物转化效率在水温33℃和21℃时呈增长趋势,在水温27℃时呈先升后降的变化趋势;在实验的摄食范围内(饥饿组除外),军曹鱼幼鱼食物转化效率随温度增加呈增长或先升后降的变化趋势,饱食时虽然食物转化效率最大值出现在33℃时,但方差分析显示33℃和27℃之间无显著性差异,其他摄食水平组在27℃时有最大值。在实验的摄食水平和温度范围内,军曹鱼幼鱼的排泄氮随摄食水平和温度的增加均呈显著增长趋势。 相似文献
7.
《海洋科学》2010,(1)
作者对鮸鱼(Miichthys miiuy)的早期发育(从受精卵到45日龄幼鱼)形态特征及生态习性进行了描述。鮸鱼的受精卵在水温21.4℃~22.0℃,盐度25.7条件下,经过29 h30 min仔鱼孵出。从受精卵到仔鱼出膜可分为卵裂期、囊胚期、原肠期、胚体形成期等4个主要时期,然后进入胚后发育阶段。孵出后的3日龄仔鱼已能在水体中平游,极少数个体可开口摄食轮虫。4日龄仔鱼全部开口摄食,并对光反应敏感,出现明显的集群现象。22日龄的后期仔鱼各鳍鳍条发育形成,鳞片开始出现,进入到稚鱼期。39日龄后,鮸鱼全身披满细小的鳞片,全部分布于育苗池的底部,开始进入到幼鱼发育阶段。根据仔、稚、幼鱼形态特征和生活习性对鮸鱼的分类进行了探讨。 相似文献
8.
黄鳍刺(鱼叚)虎鱼(Acanthogobius flavimanu)前期幼鱼摄食习性和摄食率的初步研究 总被引：1，自引：0，他引：1
对 1997年 5月莱州湾潍河口采集的黄鳍刺虎鱼前期幼鱼进行消化道内含物分析。结果表明黄鳍刺虎鱼前期幼鱼为浮游动物食性 ,主要摄食镖蚤类、短尾类幼体、猛蚤类和甲壳类的六肢幼体。摄食有明显的节律 ,清晨消化道内含物最多 ,傍晚最少。摄食的种类随昼夜不同时间有一定的变化。摄食率 :C=9.2 52 8g/ (10 0 g· BW· d) ;日摄食量 :FD=0 .0 0 4 7g/ d。 相似文献
9.
在水温(22±2)℃条件下,采用周期性停食胁迫方法研究鱼幼鱼摄食、生长和消化酶的变化情况。结果表明,饥饿组与对照组的特殊生长率差异性显著(P<0.05);不同停食时间胁迫下,试验组的摄食率和特殊生长率与对照组差异极显著(P<0.01),停食3天鱼幼鱼的食物转化率比对照组高,表明鱼幼鱼具有部分补偿能力;消化酶在不同的组织中变化情况各不相同,饥饿开始后各器官中的蛋白酶、脂肪酶和淀粉酶均下降。随饥饿时间延长,蛋白酶、脂肪酶和淀粉酶出现上升现象,但上升程度各不相同。恢复投喂后各组织中的蛋白酶、脂肪酶和淀粉酶均上升;随恢复投喂时间延长,各试验组中鱼幼鱼各器官组织中的消化酶变化情况也各不相同。 相似文献
10.
秋季黄海中南部鱼类群落对饵料生物的摄食量 总被引：8，自引：0，他引：8
研究鱼类与饵料生物之间食物定量关系进而为多鱼种资源评估提供依据,2000~2002年秋季(10~11月)在黄海中南部海域进行了定点底拖网调查,应用Eggers模型,计算了带鱼(Trichiurus lepturus)、小黄鱼(Pseudosciaena polyactis)、黄(Lophius litulon)、细纹狮子鱼(Liparis tanakae)等23种鱼类在秋季对饵料生物的摄食量。结果表明:黄海中南部23种鱼类在秋季对饵料生物的总摄食量约为309万t,其中,鱼(Engraulis japonicus)的摄食量最高(在250万t以上),占总摄食量的80.9%。中上层和底层鱼类对饵料生物的摄食量分别为262万t和47万t左右,占总摄食量的84.7%和15.3%,鱼和细纹狮子鱼分别是中上层和底层鱼类中最主要的捕食者。磷虾类是中上层鱼类最主要的食物来源,其次是桡足类、端足类和毛颚类;虾类和鱼类是底层鱼类最主要的食物来源,其次是磷虾类。太平洋磷虾(Euphausia pacifica)、中华哲水蚤(Calanus sinicus)、细长脚虫戎(Themisto gracilipes)、脊腹褐虾(Crangon affinis)和鱼同时是黄海中南部被摄食量最高的5种饵料生物,它们被摄食的生物量之和约为233万t,占总摄食量的75.5%。 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.
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
13.
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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16.
Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans 总被引：1，自引：0，他引：1
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level. 相似文献
17.
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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Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges. 相似文献