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1.
将南海北部花斑蛇鲻分成南海北部大陆架和北部湾两个不同海域群体,计算花斑蛇鲻的生长与死亡参数。得到的Von Bertalanffy生长方程的相关参数为:南海北部大陆架L∞=45.5cm,K=0.28,t0=-0.460;北部湾L∞=40.0cm,K=0.30,t0=-0.443。计算自然死亡系数得南海北部大陆架为0.63;北部湾为0.67;捕捞死亡系数南海北部大陆架为0.79,北部湾为1.11。据等渔获量曲线建议南海北部大陆架花斑蛇鲻开捕体长由13.3cm增加至20.0cm,同时,捕捞死亡系数可由当前的0.79放宽至1.0;北部湾花斑蛇鲻开捕体长由13.5cm增加至19.0cm的同时,捕捞死亡系数可由当前的1.11放宽至1.5。  相似文献   

2.
【目的】研究南海北部湾海域秋季蓝圆鲹与竹筴鱼的摄食生态特征和种间食物竞争。【方法】采用胃含物分析法,对2017年10月北部湾底拖网调查和港口随机取样收集的119尾蓝圆鲹(Decapterusmaruadsi)和198尾竹筴鱼(Trachurus japonicus)胃含物样品进行分析,通过肉眼直接观察或显微镜间接观察胃中残留的饵料,饵料种类鉴定、计数、称重等对食性做定量分析,以估算两种鱼类的营养级和生态位宽度,并利用生态位重叠研究两种鱼类的食物竞争关系。【结果与结论】蓝圆鲹的饵料种类19种(属),以桡足类和小型鱼类为主,优势饵料生物为布氏半棱鳀(Encrasicholinapunctifer);竹筴鱼的饵料种类18种(属),以小型鱼类和浮游甲壳类为主,优势饵料为中国毛虾(Acetes chinensis)。两种鱼类均为游泳动物食性,均存在摄食转换,随着叉长的增长,蓝圆鲹的饵料生物由小型浮游动物为主转变为小型鱼类为主,竹筴鱼的饵料生物由小型鱼类为主转变为以樱虾类和较大鱼类为主。蓝圆鲹和竹筴鱼的空胃率、竹筴鱼的平均胃饱满指数均随个体生长呈显著变化(P<0.05),但蓝圆鲹的平均胃饱满指数随个体生长无显著变化(P>0.05)。蓝圆鲹和竹筴鱼的营养级分别为3.63和3.40,营养生态位宽度分别为1.70和1.24,生态位重叠系数0.56,表明两种鱼类之间存在一定的食物竞争。  相似文献   

3.
南海北部花斑蛇鲻生长死亡参数估计及开捕规格   总被引:1,自引:0,他引:1  
将南海北部花斑蛇鲻分成南海北部大陆架和北部湾两个不同海域群体 ,计算花斑蛇鲻的生长与死亡参数。得到的VonBertalanffy生长方程的相关参数为 :南海北部大陆架L∞ =4 5.5cm ,K =0 .2 8,t0 =- 0 .4 6 0 ;北部湾L∞ =4 0 .0cm ,K =0 .30 ,t0 =- 0 .4 43。计算自然死亡系数得南海北部大陆架为 0 .6 3;北部湾为 0 .6 7;捕捞死亡系数南海北部大陆架为 0 .79,北部湾为 1.11。据等渔获量曲线建议南海北部大陆架花斑蛇鲻开捕体长由 13.3cm增加至 2 0 .0cm ,同时 ,捕捞死亡系数可由当前的 0 .79放宽至 1.0 ;北部湾花斑蛇鲻开捕体长由 13.5cm增加至 19.0cm的同时 ,捕捞死亡系数可由当前的 1.11放宽至 1.5。  相似文献   

4.
南海北部大陆架短尾大眼鲷生长和死亡参数估计   总被引:2,自引:0,他引:2  
根据20世纪90年代及60年代的生物学资料,运用体长频率分析法估算短尾大眼鲷的生长和死亡参数.von Bertalanffy生长方程的主要参数L∞=31.5 cm,K=0.60,t0= -0.44 ;体重的生长拐点为1.39龄;瞬时总死亡率(Z)、瞬时自然死亡率(M)和瞬时捕捞死亡率(F)分别为2.94,1.07和1.87.当前开发率为0.64,处于资源过度利用状态.  相似文献   

5.
【目的】调查闽江口龙头鱼资源,估算其生物学参数。【方法】于2015年1月、5月、8月、11月在福建闽江口11个采样点(25.85°―26.29°N,119.65°―119.87°E)采集龙头鱼3 770尾,测量其体长、体质量,用Fi SATⅡ软件中的ELEFAN I方法,估算龙头鱼的生长、死亡参数及其开捕体长和单位补充量渔获量。【结果】闽江口渔场龙头鱼体长(L)体质量(m)关系为:m=0.000 7 L~(3.804 2) (R~2=0.961 1);龙头鱼Von Bertalanffy生长方程估算的生长参数K、L_∞、m_∞、t_0分别为0.52、28.7 cm、246.1 g和-0.317龄;由生长方程推算出龙头鱼的拐点年龄约为2.252龄,拐点体长约为21.2 cm,拐点体质量约为77.1 g;根据长度变换渔获曲线法估算龙头鱼的总死亡系数为1.67,由Pauly经验公式估算自然死亡系数为1.04,捕捞死亡系数为0.63,开发率为0.377;由动态综合模型估算出龙头鱼的开捕年龄为0.712龄,对应开捕体长为11.9 cm。【结论】闽江口龙头鱼资源处未过度开发状态。  相似文献   

6.
根据20世纪90年代及60年代的生物学资料,运用体长频率分析法估算短尾大眼鲷的生长和死亡参数。von Bertalanffy生长方程的主要参数L∞=31.5cm,K=0.60,t0=0.44;体重的生长拐点为1.39龄;瞬时总死亡率(Z)、瞬时自然死亡率(M)和瞬时捕捞死亡率(F)分别为2.94,1.07和1.87。当前开发率为0.64,处于资源过度利用状态。  相似文献   

7.
北部湾二长棘鲷生长、死亡及其群体组成   总被引:6,自引:1,他引:5  
利用2006年7月至2008年3月北部湾渔业商业捕捞底拖网和刺网渔获物中采集的样本,对北部湾二长棘鲷的生长、死亡及其群体组成进行了初步研究。结果表明,北部湾二长棘鲷优势体长70~140 mm,占82.2%;优势体重为20~60 g,占54.29%;ARSS分析表明雌雄生长不存在显著性差异(P>0.05),繁殖期性比为1.21∶1;von Bertalanffy生长方程的主要参数分别为:L∞=292.8 mm,K=0.167,t0=-1.116;体重的生长拐点为5.463龄;总死亡系数、自然死亡系数和捕捞死亡系数分别为1.041 4、0.282 8和0.752 6,当前开发率为0.728。  相似文献   

8.
用SAS统计软件拟合了大鳍的体长生长方程和体重生长方程:Lt=79.5(1-e-0.0533(t+2.0982)),W=3370(1-e-0.0533(t+2.0982))2.7744,并估算了其自然死亡系数M、捕捞死亡系数F。应用Beverton-Holt模式,研究了嘉陵江水系大鳍的资源状况,为开发利用提供科学依据。  相似文献   

9.
根据2012年5~7月东南太平洋秘鲁外海(探捕海域在83°W~87°W、10°S~14°S)鲯鳅资源的探捕调查资料,对其生物学特性作了初步分析。结果表明:秘鲁外海鲯鳅的叉长范围为31~121cm,优势叉长为30~50cm,占57.4%;在个体大小的空间分布上,探捕海域北部比南部个体略微偏大;雌性叉长(l)与体质量(m)关系式为m=5×10-4·l2.236 2(R2=0.940 5;n=104 9),雄性为m=5×10-4l2.209 6(R2=0.958 0,n=851);雌性鲯鳅比例稍高,占55.2%。探捕海域鲯鳅鱼资源密度较高,CPUE值范围为2~23.6 kg/(人·h),平均为11.6 kg/(人·h);不同区域资源密度有所差异,其中CPUE最高的区域在84°W~86°W、12°30′S~13°30′S附近;探捕期间6月份的最高平均CPUE为16.37 kg/(人·h)。  相似文献   

10.
养殖条件下倒刺鲃的年龄与生长   总被引:1,自引:0,他引:1  
研究了倒刺的年龄与生长规律 ,结果表明 :倒刺鳞片年轮特征主要为疏密切割型。体长与鳞长之间的直线相关L =2 .0 85 4+2 .36 2 0R和幂函数相关L =2 .85 12R0 .952 9中 ,以幂函数相关性密切 ;体重与体长呈指数函数相关W =2 .4 984× 10 - 2 L2 .9936 。 4龄以前生长较快 ,生长指标高 ,体长指标高 ,体长和体重的相对增长率大 ,其生长规律可用VonBertalanffy方程表达 :Lt=[1-e- 0 .132 5(t+ 0 .2 0 95) ],Wt=132 76 .4 0 [1-e- 0 .132 4 (t+ 0 .2 0 95) ]3。体重生长曲线的拐点位于t =8.0 9龄、W8.0 9=3933.6 1g ,即Wt=0 .2 96W∞ 处。倒刺雌性一般在 5龄性成熟 ,雄鱼 3~ 4龄时性成熟。建议江河捕捞对象应为 5 + 龄以上的个体。  相似文献   

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12.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

13.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

14.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

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16.
《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.  相似文献   

17.
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by  相似文献   

18.
Using the NCEP/NCAR reanalysis monthly 500 hPa height data on a 2.5 latitude-longitude grid and 1°×1° sea ice data,the polar vortex area,intensity index and arctic sea ice area index are calculated respectively,and the meridional distribution,period variation and the abrupts in the long range trend are analyzed to study their relationship.The results show that the meridional distribution of sea ice and polar vortex h-ave distinctive difference,the relative positions of them are different in the eastern and western hemispheres,and exept they have periods of 4 months,quasi half year,quasi year,4-5 years and 10 years commonly,and each of them has its own respective variation as well.The sea ice area is decreasing apparently since 1980's,so is the polar vortex area,but their abrupt changge time are different totally.The area of sea ice and polar vortex has prominent positive correlation,but the relationship of sea ice intensity,polar vortex intensity,polar vortex area is complicated.  相似文献   

19.
The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.  相似文献   

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