首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
闽-粤东族大黄鱼生长性状的相关与通径分析   总被引:11,自引:0,他引:11  
研究大黄鱼各形态性状对体重的影响,测定了272尾7月龄闽-粤东族大黄鱼的全长(x1)、体长(x2)、头长(x3)、眼后头长(x4)、躯干长 (x5)、体高(x6)、尾柄长(x7)、尾柄高(x8)和体重(y),计算相关系数,采用通径分析方法计算了以体重(y)为依变量、其它性状为自变量的通径系数和决定系数.结果表明:全长、体长、头长、眼后头长、躯干长、体高、尾柄长、尾柄高和体重两两之间的相关系数均达到极显著水平(P<0.01);头长对体重的直接影响(0.429)最大,其次分别为体长(0.242)、躯干长(0.136)、体高(0.113)和尾柄高(0.079),全长、眼后头长和尾柄长对体重的直接影响不显著(P>0.05).剔除直接影响不显著的自变量建立的以体重为依变量的多元线性回归方程为(y)=-4.676 0.374×2 2.270×3 0.503×5 0 .519×6 1.254×8,其决定的数为0.940.  相似文献   

2.
星斑川鲽形态特征及相关参数的观测   总被引:2,自引:0,他引:2       下载免费PDF全文
为了给星斑川鲽的分类和种质鉴定提供基础资料,采用传统的形态学和解剖学方法,对人工养殖星斑川鲽的外部形态性状及内部组织器官系统地进行了观测和描述,采用生物统计法对星斑川鲽可量性状进行回归分析。星斑川鲽可量长度性状之间为线性关系,全长与体长回归方程为lt=1.386 4lb-0.303 5;体重与可量长度性状之间为乘幂函数关系,体重与体长回归方程为m=0.033 9lb3.060 6。结果表明不同地方种群间存在明显的形态差异。星斑川鲽的头颅骨骼特征具有鲽形目鱼类的共同特征,在筛骨区和眼区骨骼向有眼侧偏移,尾舌骨呈弓形。左右下咽骨前半部分愈合在一起,下咽齿小;具一对较薄的耳石,有5~6个乳状突。星斑川鲽属"I"型胃,幽门垂有2~4个;解剖的左眼型星斑川鲽肝脏全部在有眼侧,而右眼型星斑川鲽肝脏多在无眼侧,部分在有眼侧。  相似文献   

3.
角木叶鲽(Pleuronichthys cornutus)是中国近海重要的经济鱼类,本研究基于线粒体DNA控制区第一高变区部分序列,对采自青岛和舟山近海的角木叶鲽群体进行遗传多样性研究。线粒体DNA控制区序列分析显示:舟山和青岛两群体均呈现较高的单倍型多样度和较低的核苷酸多样度;单倍型邻接关系树与最小跨度树均显示青岛、舟山两个群体个体相互混杂,无显著的分支;群体间遗传分化指数(F_(ST)=0.027 6;P=0.030 3)揭示了两群体之间存在微弱的遗传分化;TaJima’s D中性检验和贝叶斯天际线分析的结果显示角木叶鲽群体可能经历过近期扩张事件。基础形态学特征测量结果表明,舟山群体的可量性状比值,如体长/尾柄高、体长/头长、体长/有(无)眼侧胸鳍长等均略高于青岛群体,其中体长/有(无)眼侧胸鳍长差异显著。  相似文献   

4.
花鲈形态性状对体质量的影响效果   总被引:2,自引:0,他引:2  
为深入了解花鲈(Lateolabrax maculatus)形态性状对体质量的影响效果,本研究测量了105条2龄花鲈的眼间距(X_1)、体宽(X_2)、吻长(X_3)、头长(X_4)、躯干长(X_5)、尾柄长(X_6)、头高(X_7)、体高(X_8)、尾柄高(X_9)、体长(X_(10))、全长(X_(11))和体质量(Y)这12个形态学指标。通过模型拟合筛选,获得能够反映各形态性状与体质量关系的最佳模型;运用相关分析、通径分析和多元回归分析,计算了主要形态性状的相关系数、通径系数、决定系数及相关指数,确定了影响体质量的主要形态性状,建立了最优回归方程,定量分析花鲈形态性状对体质量的影响效果。模型拟合结果显示,体宽、体高、体长、全长与体质量的最优模型决定系数R~20.85,方程分别为:y=0.045x~(2.459)、y=-1 059.959+20.392x、y=4.8×10~(-5)x~(2.785)、y=8.42×10~(-5)x~(2.616),初步得出各形态性状与体质量的关系。通径分析结果表明,体质量变异系数最大(19.770%),各形态性状与体质量的相关性均达到了极显著水平(P0.01)。通径分析中,剔除与全长存在多重共线性的头高、体高、体长及回归方程中不显著的眼间距、吻长、躯干长和尾柄长,保留了体宽、头长、全长和尾柄高4个形态性状,其中体宽对体质量的直接影响最大(P2=0.547)。所选4个性状与体质量的相关指数R~2=0.954,说明这些性状是影响体质量的主要形态参数。采用逐步多元回归方法建立的回归方程为:Y=-906.939+16.033 X_2+2.199 X_4+0.773 X_(11)+6.127 X_9。研究结果表明,在花鲈的选育过程中,其体宽、头长、全长和尾柄高可作为重要的测量指标,为花鲈选种提供依据,保证选育效果。  相似文献   

5.
为全面了解■属鱼类表型性状的种间差异,描述了我国养殖的黄条■(Seriola lalandi)、高体■(Seriola dumerili)和五条■(Seriola quinqueradiata)的形态学特征,测量了群体的表型数据,通过单因素方差分析、通径分析、主成分分析、判别分析和聚类分析等多元统计方法,对3种■鱼共计190尾样品的形态种质特征和可量可数性状进行了比较研究。单因素方差分析显示,除叉长/体长(FL/SL)、体长/尾柄长SL/PL)、头长/眼间距(HL/ID)和下颌长/上颌长(LJL/UJL)外,其余9个指标均存在显著性差异(P<0.05)。通径分析显示,黄条■的体长(SL)、体高(BH)、尾柄长(PL)和尾柄高(PD)是主要影响其体质量的4个表型性状;高体■的体长(SL)、体高(BH)、眼间距(ID)、下颌长(LJL)和眼后头长(POL)是主要影响其体质量的5个表型性状;五条■的体高(BH)、下颌长(LJL)和全长(TL)是主要影响其体质量的3个表型性状。主成分分析构建了4个主成分,其中第一项主成分贡献率为34.974%,其他3个主成分的贡献率依次为23.897%、...  相似文献   

6.
在人工养殖的条件下(自然光照,水温为11~16.3℃),对初始平均体质量为29.64g±5.98g的条斑星鲽(Verasper moseriJordan et Gilbert)幼鱼1周年的生长和生态转化效率进行定期测定。结果显示:条斑星鲽的体长和体高在实验期间皆呈直线增长;体质量的增长可以分为两个阶段:前期呈指数生长,后期为直线增长。体长和体质量呈指数函数关系:W=10-5L3.0226,r=0.9893。条斑星鲽幼鱼周年的生长率和生态转化效率都较高,属于高生长类型鱼类;生态转化效率周年波动范围是34.16%~91.07%,特定生长率的周年波动范围是0.170~1.527。  相似文献   

7.
为了研究野生小黄鱼(Pseudosciaena polyactis)繁殖后代的形态性状对体质量的影响作用,以随机采集的729尾4.5月龄小黄鱼为研究对象,对每尾个体的体质量(g)和8个形态性状(cm):全长(X1)、体长(X2)、头长(X3)、躯干长(X4)、尾部长(X5)、尾柄长(X6)、尾柄高(X7)和体高(X8)进行准确测定,运用相关分析、多元回归分析和通径分析方法,分别计算性状间的相关系数、构建形态性状与体质量的多元回归方程,获得了通径系数和决定系数,进行了养殖小黄鱼的形态性状对体质量的影响研究。结果显示,8个形态性状与体质量的相关系数均达到极显著水平(P0.01);通径分析中,4个形态性状对体质量的通径系数达到极显著水平(P0.01),它们是影响体质量的重要指标,其中体长(通径系数:0.589)对体质量的直接影响最大。应用逐步多元回归分析建立了以体质量为因变量(Y),体长(X2)、躯干长(X4)、尾柄高(X7)和体高(X8)为自变量的回归方程:Y=–32.377+3.064X2–1.511X4+14.285X7+4.438X8。模型等式中形态性状与体质量的相关指数R2=0.927,说明所选性状是影响体质量的主要形态性状。以上分析结果为小黄鱼的选育测量指标的确定提供了理论依据。  相似文献   

8.
采用相关分析、通径分析、决定分析和多元线性回归分析方法,对不同年龄组梭鱼外部形态性状对体重的影响效果进行了分析研究。结果表明,体长、体高是影响各年龄组梭鱼体重的共同性状,在0、1、3、5龄组,体长对体重的作用最大;在2、4龄组,体高对体重的作用最大。尾柄高是除3龄组外影响梭鱼体重的重点性状。头长、尾柄长对体重直接作用相...  相似文献   

9.
为了研究雷州半岛红树林短吻鲾(Leiognathusbrevirostris)各个形态特征与体质量的相关性,对随机选取的153尾短吻鲾的全长(X1)、体长(X2)、头长(X3)、体高(X4)、眼径(X5)、眼间距(X6)、吻长(X7)、尾柄长(X8)、尾柄高(X9)、吻端至第一背鳍起点(X10)、吻端至胸鳍起点(X11)、吻端至腹鳍起点(X12)、吻端至臀鳍起点(X13)等13个指标和体质量(Y)进行逐一测量,根据所得数据整理出各个性状的表型参数,计算各个指标与体质量以及不同指标两两之间的相关系数,并分别求出以体质量(Y)为因变量、其他性状(Xi)为自变量的通径系数以及决定系数。结果表明,短吻鲾的13个形态性状对体质量的相关系数皆达极显著水平(P<0.01);在通径分析中,短吻鲾仅体长(X2)、吻长(X7)、全长(X1)3个形态性状对体质量数据的通径系数达到极显著水平(P<0.01),可将其确定为影响体质量的主要性状,其中体长对体质量的直接影响最大(P2=0.570);通过逐步线性回归分析,确定回归方程为:Y=–8.366+0.570X2+0.148X7+0.266X1。决定系数显示,体长对体质量的决定系数最大,达到32.5%。各共同决定系数的总和∑d为0.908,大于0.85,表明本研究中已经将影响短吻鲾体质量的主要形态性状全部纳入。此研究有助于确定并量化短吻鲾不同性状间的关系。  相似文献   

10.
为研究东北七鳃鳗和日本七鳃鳗形态性状对体质量的影响,测量314尾东北七鳃鳗和302尾日本七鳃鳗成体的体质量(Y)和全长(X_1)、躯干长(X_2)、尾长(X_3)、头长(X_4)、吻长(X_5)、眼径(X_6)、背鳍前长(X_7)、眼后头长(X_8)8个形态性状,运用相关分析、通径分析和回归分析方法,确定影响体质量的主要形态性状,建立体质量和形态性状的多元回归方程。分析结果显示:东北七鳃鳗和日本七鳃鳗体质量服从正态分布,体质量的变异系数最大,全长、躯干长、尾长、头长、吻长、眼径、背鳍前长和眼后头长8个形态性状均与体质量呈正相关(P0.01)。经偏回归系数检验,东北七鳃鳗全长、头长、眼径和眼后头长呈显著性水平(P0.05),其通径系数分别为0.636、0.202、0.060和0.105;日本七鳃鳗全长、吻长和眼后头长呈极显著性水平(P0.01),其通径系数分别为0.730、0.098和0.153。单个性状对体质量的决定系数中,东北七鳃鳗和日本七鳃鳗全长对体质量的决定系数最大。东北七鳃鳗和日本七鳃鳗形态性状的单独决定系数和两个共同决定系数的总和分别为0.855和0.857。建立以东北七鳃鳗全长、头长、眼径和眼后头长4个形态性状为自变量,体质量为因变量的多元回归方程:Y=1.502X_1+2.699X_4+8.554X_6+1.915X_8-41.547;日本七鳃鳗全长、吻长和眼后头长3个形态性状为自变量,体质量为因变量的多元回归方程:Y=4.895X_1+9.688X_5+6.973 X_8-157.460。东北七鳃鳗和日本七鳃鳗成体形态性状对体质量的分析为七鳃鳗优良亲本的人工选育以及其形态学研究提供参考依据。  相似文献   

11.
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.
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.
Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding.  相似文献   

15.
16.
《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   

17.
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors.  相似文献   

18.
This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake.  相似文献   

19.
This study tests the hypothesis that the in situ void ratio of surficial marine sediments may be predicted from shear wave velocity-depth data with a reliability equal to that of other methods currently available. Shear wave velocity is fundamentally controlled by the number of grain-to-grain contacts per unit volume of material and by the effective stress across those contacts. In this study, three previously established empirical formulae are used to predict void ratio from velocity-depth data. Field data were acquired along a transect off the northern Californian coast across which water depth increased from 35 to 70 m and seafloor sediment type varied from sand to silty-sand, respectively. A towed seafloor sled device was used to collect shear wave refraction data, and a marked, systematic decrease in velocity was observed along the line, ranging from 35-70 m/s for the coarse, near-shore material to 25-40 m/s for the finer, offshore deposits. Void ratios predicted from these velocities were compared with data measured directly from box-core samples. Of the formulae used for prediction, two agree remarkably well with the control data. Both predicted and control values increase from 0.6-0.8 for the sandy material to 1.1-1.5 for the silty-sand. Thus, this study does not disprove the hypothesis set and demonstrates the potential of field shear wave velocity-depth data as a means of delineating spatial variation in void ratio for surficial marine sediments in a remote, nondestructive manner.  相似文献   

20.
Particulate samples were collected from the Changjiang river system during a flood period, in May 1997, and POC, stable isotope and lipids associated with particles were examined. Results showed the decrease (0.84% ~ 1.88%) of organic carbon content from the upper reaches to the estuary.δ13C values of particulate organic carbon was in the range of -24.9×10-3 to -26.6×10-3, which were close to the isotopic signature of continental C3 vegetation. Total particulate n-alkanes concentrations varied from 1.4 to 10.1μg/dm3,or from 23.7 to 107μg/g of total suspended matter. Fatty acids were present in all the samples, from 1.4 to 5.4μg/dm3, with saturated and unsaturated straight-chain and branched compounds in the carbon number range from C12 to C30. Both δ13C and the ratio of carbon content to nitrogen content indicate the predominance of terrestrial inputs (soil organic matter) among the particles. The biomarker approach has been used to identify the relative portion of terrigenous and autochthonous fraction in the particulate samples. The distribution of fatty acids suggests a striking phytoplanktonic and microbial signal in most particle samples. The terrestrial alkanes are used to estimate the contribution of terrestrial inputs along the mainstream.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号