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1.
中国近海带鱼种群生化遗传结构及其鉴别的研究   总被引:18,自引:1,他引:18  
用淀粉胶和聚丙酰胺凝胶电泳,分析了中国近海带鱼9个取样群体472尾鱼的11种同工酶,并对它们进行了生化遗传分析,共记录出24个基因座位。各取样群体遗传相似度和遗传距离的计算表明,中国近海的带鱼不是过去认为的一个种,3-5个种群,而是存在3个不同的种8个种群。  相似文献   

2.
南海北部带鱼生长死亡与参数动态综合模式   总被引:9,自引:1,他引:9  
根据我国近海带鱼分种研究结果,利用南海北部底拖网调查收集的带鱼属3鱼种的生物学资料,运用长度频率法估算了3鱼种的生长和死亡参数.带鱼、南海带鱼和短带鱼von Bertalanffy生长方程的渐近肛长分别为70.0,54.5和48.0 cm;生长系数分别为0.27,0.27和0.17;理论生长起点年龄分别为-0.60,-0.68和-1.10龄.用长度变换渔获曲线法估算的3鱼种总死亡系数分别为3.02,0.80和2.43;用经验公式估算的自然死亡系数分别为0.39,0.58和0.44;捕捞死亡系数分别为2.63,0.22和1.99.动态综合模式的分析结果表明,3鱼种都能承受较大的捕捞压力,资源利用的不合理之处是大量捕捞1龄以内的幼鱼;在最适利用状态下,带鱼、南海带鱼和短带鱼的开捕年龄分别应为3.0,2.0和2.7龄,对应的肛长分别为44,28和23 cm.  相似文献   

3.
中国近海带鱼种群生化遗传结构及其鉴别的研究   总被引:19,自引:2,他引:17       下载免费PDF全文
用淀粉胶和聚丙烯酰胺凝胶电泳,分析了中国近海带鱼(Trichiurus)9个取样群体472尾鱼的11种同工酶.并对它们进行了生化遗传分析,共记录出24个基因座位.各取样群体遗传相似度和遗传距离的计算表明,中国近海的带鱼不是过去认为的一个种、3~5个种群,而是存在3个不同的种8个种群.  相似文献   

4.
圆筛藻属的种类是南海近岸浮游植物中的优势种或习见种,又是海洋动物的直接或间接食物。近年来随着石油工业的迅速发展,发现在油田岩心样品中也保存着一些圆筛藻,因此有必要了解我国圆筛藻的种类和分布,供作我国资源开发的参考。关于南海圆筛藻的分类研究,金德祥等报告过14种1变种。郭玉洁报告过圆筛藻属的5个新种。郭玉洁等报告过采自西沙群岛和中沙群岛及其附近海域的圆筛藻9种。本文主要报告采自广东省近海和北部湾东部的圆筛藻13种7变种,其中4种6变种在我国是首次记录,1种和1变种是世界新记录。到目前为止,在南海已记录圆筛藻24种7变种。本文除对产自我国南海的圆筛藻的壳面特征进行绘图、描述和拍照外,并对其环面也进行了详细描述和绘图,以补充以往文献的不足。对于在西沙和中沙群岛及其附近海域已作过详细形态描述的种类如高圆筛藻(Coscinodiscus nobilis Gruu.)等,在此则不再重复。各种名下仅列出其原始定名文献和国内资料,对国外的一般性文献则从略。本文绝大部分种类的学名均根据科学出版社出版的《藻类名词及名称》(1979)。  相似文献   

5.
中国近海带鱼分种的研究   总被引:6,自引:2,他引:4       下载免费PDF全文
1976~1992年,主要用生化遗传方法并辅之以形态学资料,共分析了中国近海的1 400余尾带鱼的样品.生化遗传资料分析了11种同工酶,共记录出24个基因座位,其中4种酶9个基因座位具有种的特异性.结果表明中国近海带鱼存在3个种,它们之间的遗传距离在0.2230~0.3822之间.形态学资料与生化资料的结果是一致的,也表明中国近海带鱼存在3个种,它们之间存在着明显的不连续的差异.3种带鱼中有2个新种,分别命名为南海带鱼Trichiurus nanhaiensis Wanget Xusp. nov.和短带鱼Trichiurus brevis Wanget You sp.nov.  相似文献   

6.
带鱼(Trichiurusjaponicus)是广泛分布于东亚大陆架海域的暖温性近底层经济鱼类,也是东海区最重要的海洋渔业捕捞对象。然而,目前的研究报道对东海近岸带鱼群体遗传变异特性认识不足,不利于其种群的遗传资源保护和管理。本研究利用线粒体控制区序列对东海近岸带鱼6个群体191个个体的遗传多样性、遗传分化和历史动态进行分析。在577 bp长的控制区序列中共检测到70个多态位点,定义了121个单倍型。群体总的单倍型多样性较高(0.9911),但总的核苷酸多样性较低(0.0092),群体间遗传多样性水平差异较小。单倍型遗传学关系、Fst值和分子方差分析结果均表明群体间的遗传分化不显著,存在广泛的基因交流。历史动态分析结果表明东海近岸带鱼群体在更新世中晚期可能经历了瓶颈效应和随后的群体快速扩张,这是导致群体遗传多样性较低的主要原因。带鱼较强的扩散能力、洄游行为、海洋环流以及近期的群体扩张可能是造成东海近岸带鱼缺乏显著的系统地理种群结构的原因。研究结果提示,在线粒体DNA水平上,东海近岸带鱼群体是一个随机交配的种群,在遗传资源管理上可作为一个单元进行管理。  相似文献   

7.
8.
关于带鱼Trichiurus haumela(Forskal)形态学的研究,迄今仅在消化器官和骨骼系统方面有过记载,实际上形态研究对了解鱼类分类位置等有关问题极有参考价值.作者本着上述认识对带鱼的内脏器官进行了较系统的观察,并在此基础上,从形态特征,结构功能与生活习性间的关系方面对带鱼的,分类提出了讨论。  相似文献   

9.
南海海底地势复杂,海域内跃层分布有其特殊性,研究声速跃层分布形态对海上军事活动和海洋战场建设有重要影响。利用50a(1958~2007年)SODA(simpleoceandataassimilation)月平均资料,采用垂直梯度法分别求得3种类型声速跃层的特征值。结果表明:冬季,3种类型声速跃层范围全年最小,厚度最薄,强度最弱;夏季,主跃层、双跃层范围全年最大,厚度最厚,深度大都较浅,强度最强。春秋季跃层的示性特征介于冬夏之间,秋季比春季变化明显。  相似文献   

10.
张仁斋  陈士群 《台湾海峡》1991,10(4):373-379
本文观察了太平深海带鱼早期发育形态,主要特征是背鳍第一棘延长呈鞭状,向后可达体长的1/2以后,随着鱼体的长大,延长的鳍棘退化。到后期仔鱼,腹鳍和臀鳍分别生有刺和棘,形状尖利。发育到稚鱼期臀鳍第二棘长大,似蝉翼状。随着鱼体长成幼鱼时,腹鳍刺和臀鳍棘相继退化。  相似文献   

11.
This study analyzed the factors structuring demersal fish community in a tropical bay in southeastern Brazil. The results were used to quantify the partitioning of ecological variation among the environmental, spatial and temporal components molding the fish community. Three bay zones (inner, middle and outer) were defined according to depth and salinity gradient. Monthly samplings were conducted by bottom trawl tows during daylight hours, between October 1998 and September 1999. In each zone, three replicate samples were taken. Ninety-three fish species from 73 genera and 37 families were recorded in the 108 samples. Two demersal fish assemblages were evidenced, one in the inner and the other in the outer zone. These assemblages were characterized by changes in species composition and relative abundance. Depth, followed by transparency and salinity, influenced spatial pattern of fish assemblages. The largest part of the explained variation occurred as a result of the spatial structure of environmental variables, which means that both species and environmental variables presented similar spatial structure. The spatial effect, not the seasonal, explained the highest part of species variations. The amount of unexplained variation was relatively high (76%), even assuming that part of it is due to nondeterministic fluctuation, which could be due to local effects of unmeasured (biotic and abiotic) controlling variables. Knowing the relative importance of these factors can be of decisive importance when applying casual hypotheses in the framework of some precise ecological theory and should facilitate management, planning, and usage of bay resources.  相似文献   

12.
采用聚丙烯酰胺梯度凝胶垂直平板电泳对湛江、北海和汕尾三地翡翠贻贝(Perna viridis)野生群体10种同工酶21个的位点的生化遗传特性进行分析.分析结果表明8个位点(Alp-1, Alp-2, G6pdh-1, Me-1, Me-2, Sdh-1, α-Est-5, β-Est-2)具有多态性.湛江、北海、汕尾群体的多态位点比例分别为0.381,0.286,0.381,平均期望杂合度分别为0.6 097, 0.5 407和 0.6 893.群体内杂合度较高,遗传多样性较丰富.群体间的基因分化系数在 0.0 140 ~ 0.0 389 范围内,北海和湛江群体间,湛江和汕尾群体间以及北海和汕尾群体间的遗传相似性分别为0.9 838,0.9 861 和 0.9 630; 聚类分析表明湛江和汕尾群体遗传距离极小,而与北海群体分歧稍明显.上述的结果表明,翡翠贻贝 3 个群体种质资源遗传多样性依然处于良好状态.  相似文献   

13.
鲈鱼群体生化遗传研究Ⅱ.种群生化遗传结构及变异   总被引:12,自引:0,他引:12  
1995年6月-1996年5月分别在汕头及青岛收集共100尾鲈鱼生化样品,采用淀粉胶及聚丙烯酰胺凝胶电泳分析了鲈鱼17种同工酶,记录了31个基因座位,统计卫基因频率,结果表明,2群体间遗传相似度和遗传距离分别0.9920和0.0080,作者初步认为中国近海鲈鱼为1个种,分南,北2个种群,汕头种群多态座位比例为22.6%,青岛种群为25.8%,x^2检测表明,2个群体多态座位等位基因频率除汕头的Est-4外均符合Hardy-Weinberg平衡,汕头与青岛种群平均杂合度分别为0.079和0.099,表明目前鲈鱼种质资源状况尚好,但当前捕捞鲈鱼苗的压力过大,应严格控制鲈鱼苗的捕捞,以免因滥捕仔稚幼鱼而导致资源衰竭。  相似文献   

14.
    
Fish assemblages in an insular (preserved) and a continental (disturbed) sandy beach were compared to assess any changes that could be attributed to anthropogenic influences and/or the proximity of the fish spawning grounds. We expected that the closer geographical position to the spawning grounds and the small amount of anthropogenic disturbance on the insular beach would be likely to provide more suitable conditions for early fish development compared with the continental beach. A total of 192 samples (96 in each beach) were taken, yielding 68 fish species, mostly young‐of‐the‐year. Fish assemblage structure differed significantly between the two beaches. Moreover, the insular beach had higher number of species, number of individuals and biomass compared with the continental beach. The commercially important Clupeiformes Harengula clupeola, Anchoa tricolor and Anchoa januaria, Perciformes Micropogonias furnieri and Mugiliformes Mugil liza were typical species on the insular beach, partitioning the seasonal use of the beach. On the other hand, a few abundant non‐commercial species, mainly the Atheriniformes Atherinella brasiliensis and the Perciformes Eucinostomus argenteus and Diapterus rhombeus, occurred all year round at the continental beach. The high fish richness and abundance and the more conspicuous species turnover across seasons on the insular beach are probable indications of more complex and dynamic organization of the communities favored by better geographical position and less anthropogenic disturbance in the area.  相似文献   

15.
一个皱纹盘鲍人工群体内个体大小遗传变异的RAPD分析   总被引:11,自引:1,他引:11  
从以日本野生皱纹盘鲍(Haliotis discus hannui Ino)为亲本进行群体繁殖所得人工群体的子1代中分别选择大(BI)、中(ME)、小(SM)等3个子群体各20个个体,进行RAPD分析。用11条随机引物及7个双引物组合共扩增出153条DNA片段,其中总群体多态性片段数为110条,多态性片段的比例为72.37%。根据扩增片段的共享度用TFPGA软件进行计算,结果表明:(1)SM与ME的遗传距离较近,而与BI的遗传距离相差较大;(2)子群体间遗传分化系数为7.64%,表明各个子群体间在遗传上存在一定的差异,对子群体进行选择将有一定的意义;(3)各子群体表现出了丰富的遗传变异,子群体BI、ME、SM的遗传多样性分别为0.2063、0.2358和0.2363,表明BI子群体具有相对较高的纯合度,在选择育种中有较高价值。  相似文献   

16.
坛紫菜品系间遗传差异的RAPD分析   总被引:9,自引:1,他引:9  
利用RAPD技术对六个坛紫菜品系进行了研究,从107条随机引 物中筛选10条随机引物,一共扩增出93条可重现的片段。经统计分析,六个品系间的遗传相 似系数在0.246~0.636之间。其中浙江北部沿海栽培品系间的相似系数最高为0.636.地 域间品系的遗传相似系数最低为0.246。六个品系用UPGMA方法得到的聚类关系符合传统的地 域和表型关系。通过对照品系间有稳定差异的DNA条带,表明RAPD标记是坛紫菜品系鉴定和 遗传多样性分析的有效手段。  相似文献   

17.
The evaluation and management of fisheries resources requires knowledge of spatial and temporal changes in the habitat-associations of fishes. However, most studies concerning habitat associations of small fishes in the shallow regions of estuaries have been limited to daytime sampling strategies. Diel changes were investigated in assemblages of fishes associated with shallow seagrass (Zostera capricorni) and bare sand in two estuaries in south-eastern Australia. Habitat-related differences in assemblages were strong day and night, and were greater than diel changes in assemblages. The seagrass-associated assemblages remained similar day and night and consistently differed from those associated with bare sand. In contrast, the assemblages over sand varied on a diel basis as larger individuals of several species (e.g.Gerres subfasciatus,Platycephalus fuscus) that resided over other (deeper) habitats during the day were caught over shallow sand at night. Further, some species (e.g.Ambassis jacksoniensis) that resided in seagrass during the day occurred over sand at night. Both habitats were utilized by newly recruited juveniles of economically important species and the habitat-associations of these species generally did not differ on a diel basis. Therefore, both habitats are considered important to the fisheries resources of south-eastern Australia. Inclusion of night-time sampling provided a greater understanding and appreciation of the use of the unvegetated habitat by fishes than has previously been acknowledged from studies based solely on daytime sampling. This study indicates that greater consideration of temporal changes in habitat associations of fishes is required in other geographic regions.  相似文献   

18.
采用聚丙烯酰胺凝胶电泳技术对半滑舌鳎野生和养殖4个群体的遗传结构进行了比较研究.结果表明,半滑舌鳎养殖群体遗传变异水平低于野生群体,两个野生群体的多态位点百分数、观察杂合度、期望杂合度、平均有效等位基因数的平均值(分别为21.275%、0.1177、0.0854和1.1499)分别高于两个养殖群体的平均值(分别为18....  相似文献   

19.
    
The knowledge of prey small ?sh stock, distribution and abundance is necessary to guide stocking of piscivorous ?sh for the biomanipulation in domestic tap water lakes. This study describes the current status of small ?sh community in Kuilei Lake(China), and examines the spatial and seasonal variations of the community in relation to key environmental factors. Based on submerged macrophyte cover and water depth, the lake was divided into ?ve major habitats:(1) macrophyte covered shallow habitat of water depth< 2.00 m,(2) uncovered or less-covered shallow habitat(2.00 m–3.50 m),(3) uncovered medium shallow habitat(3.50 m–5.00 m),(4) uncovered medium deep habitat(5.00 m–6.50 m) and(5) uncovered deep habitat(6.50 m–8.50 m). The abundance and composition of small ?sh were monitored by benthic fykenet sampling from April 2013 to January 2014. A total of 2881 individuals belonging to 5 families and 21 species were collected. Based on their abundance(accounted for 88.96% of the total) and occurrence(more than 33.33%), Acheilognathus chankaensis, Acheilognathus macropterus, Microphysogobio microstomus,Pseudorasbora parva and Rhinogobius giurinus were recognized as dominant small ?sh species. The results of correlation analysis identi?ed that species richness( Sr), Shannon-Wiener diversity index( H′)and Margalef′s richness index( D) were signi?cantly negatively correlated with water depth, but positively correlated with biomass of submerged macrophytes.Redundancy analysis(RDA) revealed that the spatial distributions of most small ?shes were negatively associated with water depth. The details of these ?ndings are bene?cial to understanding the adaptation of the small ?shes in degraded environments, and to developing suitable biomanipulation strategies for the management of ?sh resources and water quality in the lakes along the lower reach of the Changjiang(Yangtze) River basin.  相似文献   

20.
用同工酶谱法发现中华乌塘鳢Bostrichthy sinensis四个群体的遗传变异水平很低,在所检测的30个基因座位中,多态座位比例只有0—10%,平均杂合度仅为0.2—0.5%,物种的平均杂合度为0.33±0.10%。四个群体共享常见的等位基因。虽然其中三个群体拥有特有的等位基因,但其基因频率都未超过5%。四个群体的Nei氏遗传距只有1.68—12.13×10~(-5)。据分析,近交可能是遗传变异水平低和形态特征分化差的主要原因。种苗生产上应注意广泛采集不同地理群体的鱼作亲鱼,以丰富养殖群体的基因库。  相似文献   

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