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1.
荣成俚岛和胶南斋堂岛斑头鱼渔业生物学特征的比较研究   总被引:1,自引:0,他引:1  
对2010年10月采自荣成俚岛和胶南斋堂岛近海的斑头鱼(Hexagrammos agrammus)繁殖群体生物学特征进行了比较分析.研究结果表明:两个群体斑头鱼的体长组成和体质量组成差异不显著,优势体长组均为100~150mm,优势体质量组分别为20.0~50.0g和30.0~70.0 g;体长与体质量关系分别为W=2.0×10-5L3.0.257(R2=0.968 7)和W=1.0×10 5L3.0805(R2=0.943 8),肥满度指数(K)分别为1.83±0.19和2.08±0.20.荣成俚岛斑头鱼较胶南斋堂岛群体的生长速度慢、肥满度指数低,但卵径大、性成熟较早.斑头鱼雌雄个体的性腺成熟度和性成熟系数均与体长呈正相关关系;肝脏指数和肥满度指数变化可作为判定斑头鱼繁殖时期的重要依据.水温不同造成2个群体繁殖期差异,胶南斋堂岛群体繁殖时间相对滞后.  相似文献   

2.
淀山湖主要放流鱼种鲢和鳙生长的研究   总被引:1,自引:0,他引:1  
本文根据2006-2008年淀山湖鲢鳙标记回捕数据以及刺网调查数据,研究了淀山湖鲢鳙的生长,根据鱼类体长推算公式分别推算出鲢鳙的生长指标;并计算出淀山湖鲢鳙的体长体重关系和肥满度.体长和体重关系分别为鲢:W=6×10-5 L2.8371,(n=216,R2=0.8886);鳙:W=5×10-5L2.5609,(n=55...  相似文献   

3.
根据2014年5月、9~11月在威海市中心渔港拖网渔获物中采集的白姑鱼(Pennahia argentata)样本,利用一种稳健的贝叶斯方法研究了白姑鱼体长(全长、标准体长)与体重的关系。为得到可靠的参数估计值,将体长与体重关系式转化为线性模型,利用t分布建立参数的似然函数,通过数据标准化方法得到白姑鱼体长与体重关系式参数的后验概率分布。结果显示,本文方法可以较好估计白姑鱼体长与体重关系式参数的后验概率分布,由标准化数据计算的斜率和截距间不存在相关关系。t分布参数ν的估计值随体长与体重数据而发生变化,其分布范围为27.87~56.5。春季、秋季和全年白姑鱼的全长与体重关系式分别为W=2.540×10~(-3) TL~(3.4662)、W=4.308×10~(-3) TL~(3.3223)和W=3.963×10~(-3)TL~(3.3406),标准体长与体重关系式分别为W=1.083×10~(-2)SL~(3.2051)、W=1.498×10~(-2)SL~(3.1201)和W=1.403×10~(-2)SL~(3.1347)。春季与秋季白姑鱼的全长与体重关系、标准体长与体重关系存在显著性差异,春季白姑鱼参数b大于秋季,参数a小于秋季。威海近海白姑鱼属正异速生长种类,雌、雄群体的全长与体重关系和标准体长与体重关系均不存在显著性差异。黄海白姑鱼参数b的值与东海和南海北部白姑鱼b的值可能存在显著差异。本文的贝叶斯方法可用于估计鱼类体长与体重关系式参数及其不确定性。  相似文献   

4.
湖北道观河水库青梢鲌(Culter dabryi)的个体生殖力   总被引:8,自引:1,他引:8  
于2001年4、5月份,从道观河水库中随机采集青梢鲌成熟雌体53尾,用鳞片鉴定年龄(A),测量了体长(L)、体重(W)、净体重和性腺重(Wo)等形态学指标,计数个体绝对生殖力(F),并计算出青梢鲌的体长相对生殖力(FL)、相重相对生殖力(FW)、肥满度(CF)和成熟系数(GSI)等,用8种数学模式及多元回归方程拟合了青梢鲌个体生殖力与形态学指标间的关系。结果表明,青梢鲌样本由1 —4 龄鱼组成;其个体绝对生殖力与体长、体重和年龄分别呈抛物线、幂函数和幂函数相关,相关式分别为:F=-1.032 0.00754L2(n=53,R2=0.6920,P<0.01),F=0.0287W0.911(n=53,R2=0.7315,P<0.01),F=0.339A1.489(n=53,R2=0.6211,P<0.01);体长相对生殖力与体长、体重和年龄分别呈对数函数、对数函数和直线相关,相关式分别为:FL=-4995.579 2001.462lnL(R2=0.7315,n=53,P<0.01),FL=-1869.419 622.496lnW(R2=0.7315,n=53,P<0.01),FL=-71.679 6323.410A(R2=0.7315,n=53,P<0.01);体重相对生殖力均值约219粒/g,变幅主要为150—300粒/g;多元逐步回归分析其绝对生殖力和体长相对生殖力均与多个指标密切相关,相关式分别为:F=-1.248 0.070GSI 0.0571L×W(n=53,R2=0.8212,P<0.01),FL=-1050.940-26.756W 46.031Wo 97.941L×W(n=53,R2=0.7243,P<0.01);而体重相对生殖力仅与成熟系数有相关性:FW=144.186 8.222GSI(n=53,R2=0.3246,P<0.01)。  相似文献   

5.
细鳞鯻年龄与生长的研究   总被引:2,自引:0,他引:2  
选用胸鳍覆盖处的鳞片作为细鳞(鱼剌)(Therapon jarbua(Forssk(a)l))的年龄鉴定材料,其年轮形成时期主要在2~4月.体长与鳞径呈线性关系.体长-体重关系为W=3.8891×10-2L2.8761.vonBertalanffy生长方程适合描述其体长和体重的生长,生长参数为L∞=35.9cm,W∞=1153.7g,k=0.2376,t0=-0.2115.体重生长在4.41a具一拐点,此时体重生长速度达到最大.  相似文献   

6.
网箱养殖大黄鱼生长特性的研究   总被引:1,自引:0,他引:1  
对宁德地区网箱养殖大黄鱼(Pseudosciaena crocea)生长特性进行了研究。测定了780尾大黄鱼25个月龄的各项生长数据,体长变幅为20.5~320.0 mm,体质量变动范围为0.281~555.5 g;生长指标显示,体长生长指标为0.208~2.123,体质量生长指标为0.529~47.579;肥满度波动范围为1.74%~2.37%;肝指数变动范围为0.92%~2.07%;鳔生长指数为1.08%~1.85%;雌鱼性腺成熟系数为0~10.04%,而雄鱼则为0~2.27%。以Keys氏公式W=aLb,拟合25月龄养殖大黄鱼的体长(L)与体质量(W)的关系式为:W=0.0195 L 2.9775(R2=0.9959),其中b≈3,即此生长阶段的网箱养殖大黄鱼生长均匀,为等速生长类型;体质量生长呈幂函数生长,其回归方程为:y=1.8617x1.8099(R2=0.9931)。体长Y(cm)与养殖时间X(月龄)的生长呈二次多项式关系,其回归方程为:y=?0.0259x2+1.7125x+4.1534(R2=0.989)。  相似文献   

7.
根据2011年海州湾及邻近海域的底拖网调查资料,对大泷六线鱼(Hexagrammos otakii)的群体结构、体长-体重关系、生长、死亡和资源利用状况进行初步研究。结果表明:大泷六线鱼渔获群体体长范围为44~292mm,优势体长组为54~74mm,平均体长为88mm;体重范围为0.35~574.3g,优势体重组为10g,平均体重为17.94g;体长-体重关系为W=4.23×10-6 L3.31(R2=0.978 6,n=1 514)。应用FiSATⅡ软件中的ELEFANⅠ方法估算的von Bertalanffy生长方程参数L∞、K和t0分别为328mm、0.36a-1和-0.43a;应用FiSAT软件中变换体长渔获曲线法求得总死亡系数Z为2.06,自然死亡系数M和捕捞死亡系数F分别为0.62和1.44,开发率E为0.70。Beverton-Holt单位补充量渔获量模型分析表明,在现行捕捞死亡系数F=1.44、YW/R取最大值时对应的开捕年龄为1.83a。现阶段大泷六线鱼资源已处于过度开发状态,考虑拐点年龄、临界年龄、繁殖和经济效益等综合因素,建议将海州湾大泷六线鱼最适开捕规格定为体长191mm。  相似文献   

8.
青岛近海许氏平鲉年龄与生长特性的研究   总被引:1,自引:0,他引:1  
2004年3月—2005年1月逐月在青岛近海采集许氏平鲉(Sebastes schlegelii)样本共计147尾,以矢耳石为年龄鉴定材料对其年龄和生长特性进行了研究。耳石边缘增长率分析表明,许氏平鲉耳石年轮形成的周期为1年,6~7月是年轮形成高峰期。协方差分析和残差平方和分析表明,许氏平鲉的体长与体重、年龄与生长关系在雌雄性别间无显著性差异(P0.05),其体长(L)与体重(W)的关系式为W=1.750×10-5×L3.084(r2=0.990,P0.05);使用年龄和体长的实测值拟合其生长,Von-Bertalanffy体长生长方程为Lt=367.211×(1-e-0.576×(t-0.399))(r2=0.943,P0.05)。分析表明,在耳石形态与重量各测量参数中,耳石重量(Wotolith)与年龄(t)的线性相关性最密切(r2=0.942),其关系式为Wotolith=-0.023+0.035 t。平均百分比误差指数(IAPE)结果显示,耳石重量可以作为青岛近海许氏平鲉年龄鉴定的有力手段(IAPE=8.3%)。与1980年代相比,青岛近海许氏平鲉生长加快,显示出资源进一步衰退的迹象。  相似文献   

9.
池养乌苏里拟鲿雌雄鱼生长及周年性激素与性腺发育研究   总被引:2,自引:0,他引:2  
乌苏里拟鲿(Pseudobagrus ussuriensis)的种质资源保护和商品鱼养殖正在我国悄然兴起。本文首次研究了乌苏里拟鲿雌、雄鱼在池塘养殖条件下的生长规律以及性成熟鱼周年性腺发育与性激素变化特性。研究结果表明,乌苏里拟鲿随着年龄的增长,雌鱼和雄鱼之间的体质量、体长差异逐渐明显,雌鱼体长与体质量的关系式为:W=0.182 5L1.964 6(R2=0.944 5);雄鱼体长与体质量的关系式为:W=0.188 1L2.0059(R2=0.961 8)。在12月份(2龄鱼)至翌年10月份(3龄鱼)期间,雌、雄鱼丰满度呈下降趋势,成熟度、血清雌二醇(E2)和睾酮(T)水平均呈先升高后下降的变化规律。雌鱼的E2和T在5月份达到最高值,分别为(1 624.23±331.4)pg/mL和(1 320.85±279.12)pg/mL;雄鱼的E2在5月份达到最高值(323.17±147.36)pg/mL,而T的最高值则出现在4月份,为(758.33±100.47)pg/mL。雌、雄鱼性腺发育和成熟度基本同步,从外观和组织学观察对性腺的分期显示,2龄乌苏里拟鲿在12月份的精巢和卵巢已发育至第Ⅲ期,在次年6月份均达到第Ⅴ期。  相似文献   

10.
牙鲆年龄和生长的研究   总被引:6,自引:1,他引:6  
本文根据1980—1986年间连续逐月牙鲆生物学测定和耳石观察资料,确认其年轮形成期在3—5月,主要在4月。经标准von Bertalanffy生长方程拟合,鱼体体长(mm)年间生长规律为: ♀:L_t=800.10[1-e~(-0.2323(t-0.0254))] (?):L_t=690.62[1-e~(-0.2557(t+0.1211))]依体长与体重间相关关系计算渐近体重和最大生长速度,雌鱼分别为8370.43g和865g/a;雄鱼分别为4867.15g和554g/a。对低龄鱼(0—Ⅲ)生长特征模拟结果表明,雄鱼体长生长的季节变动幅度(C=1.07,k=0.5925)明显大于雌鱼;当年生雄鱼在7—9月的生长速度为年内最大。  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.
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.
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   

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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.
Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.  相似文献   

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《海洋学报(英文版)》2014,(8):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   

20.
This article presents a methodology developed to evaluate the instability of submarine slopes that extend over a large area. Special attention was paid to (1) the complex geometry (bathymetry) and the expanse of the slope, (2) the heterogeneity of the sediment, and (3) the distribution of the pore pressure. The safety factor was considered as a spatially varying quantity. The General Formulation (GLE, Fredlund and Krahn 1977), which fully satisfies equilibrium conditions, was used for evaluating the stability of the marine slope. The submarine slope failure, which occurred on 16 October 1979 during the construction of the new Nice airport, was studied in order to test the developed model. Geotechnical parameters were taken from experimental tests carried out by IFREMER on 19 cores extracted at different depths (from 27 m to 1300 m) (Cochonat, Bourillet, and Savoye, 1993; Mulder et al., 1994). Many scenarios were proposed in order to explain the cause of the Nice slope failure (Habib, 1994). In this article, two of those scenarios were tested. Simulation results are presented and discussed.  相似文献   

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