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1.
大眼金枪鱼(Thunnus obesus)是世界最重要的渔业资源之一,经济价值较高,捕捞压力的加大使中部太平洋大眼金枪鱼过度捕捞程度愈发严重。开展种群遗传结构研究将为大眼金枪鱼资源的可持续利用与开发提供科学依据。本文以取自中西太平洋和中东太平洋共182尾大眼金枪鱼个体为研究对象,分析研究其线粒体DNA控制区第一个高变区(the first hypervariable region,HVR-1)457bp的序列,共发现115个变异位点,定义了178种单倍型。序列多样性分析结果显示:8个采样点核苷酸多样性在0.03074—0.04362之间,单倍型多样性在各个采样点都较高,变动范围在0.996—1.000之间;分子方差分析显示99.97%的遗传变异性来自于种群内;群体间的高基因交流值Nm和低分化指数Fst揭示中东太平洋与中西太平洋群体间基因交流频繁,不存在显著的遗传分化。 相似文献
2.
测定了福建近海鮐鱼(Scomber japonicus)2个群体共62尾个体的线粒体DNA(mtDNA)控制区序列,探讨了闽东、闽南群体的遗传结构和遗传多样性.获得长度为864 bp的控制区全序列,在所分析的62个样本中,共检测到35个变异位点,定义了36个单倍型,平均单倍型多样性(h)为0.960,核苷酸多样性(π)为0.009 85,核苷酸差异数(K)为8.508,提示鮐鱼是一个遗传多样性水平较高的稳定的大种群.构建的单倍型邻接关系树和单倍型网络图均没有表现出明显的地理分布特征.分子方差分析(AMOVA)表明,遗传变异全部存在于群体内个体间,2个群体间具有相似的遗传结构.群体间和群体内的Kimura双参数遗传距离均为0.01.Tajima’s D中性检验及核苷酸不配对分析暗示鮐鱼是一个平衡的大种群,mtDNA控制区符合中性理论进化.结果显示,福建近海鮐鱼遗传多样性较高,闽东、闽南群体间不存在显著的遗传分化.扩散能力、种群大小、栖息地环境和台湾海峡环流促进了鮐鱼2个群体间频繁的基因交流,可能是闽东群体和闽南群体具有相似遗传结构的重要原因. 相似文献
3.
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
4.
秋刀鱼主要分布在西北太平洋亚热带到温带水域中,是一种资源量较高的上层洄游性鱼类。为了对秋刀鱼的遗传结构进行研究,2016年6月-11月,在38°38′-44°31′N,146°36′-162°26′E海域随机取145条秋刀鱼,取其肌肉与DNA、PCR以及测序后获得421 bp基于线粒体细胞色素b (Cytb)基因的DNA序列。分析结果显示,145条序列中共发现了15个单倍型,单倍型多样性指数h=0.258±0.049,核苷酸多样性π=0.000 87±0.007 56。计算得出Tajima′s D与Fu′s Fs均呈负值并且绘制的核苷酸不配对曲线呈现单峰,可得出秋刀鱼群体经历了种群扩张。Nm值表明4个采样点的秋刀鱼群体之间存在频繁的基因交流,AMOVA分析结果显示97.22%的遗传变异来自群体内,结合遗传分化系数Fst得出群体遗传分化水平较低。单倍型网络图呈现星状拓扑结构、系统发育树分枝不明显均显示地域性差异不显著。研究发现秋刀鱼群体遗传多样性较低,需对其进行合理保护。 相似文献
5.
为了探究球状伪镖水蚤群体的遗传多样性及其遗传结构，本研究以线粒体细胞色素氧化酶Ⅰ（mtCOⅠ）基因作为分子标记，提取了中国东南沿海地区5个采样点135只球状伪镖水蚤个体的基因组DNA并进行分析。结果表明：在获得的580bp的COⅠ基因序列中，碱基A+T的平均含量为63.4%，明显高于G+C的含量（36.6%），显示出较强的AT偏好性。5个采样群体共检测到49个多态位点和38个单倍型，单倍型多样性指数（h：0.6285—0.9214）和核苷酸多样性指数（π：0.00766—0.02010）均处于较高水平，各群体之间遗传距离为0.009—0.031。系统进化树和单倍型网络图显示：5个采样群体聚成多个支系；除广州与顺德、上海与无锡以外，其他各采样群体之间均具有显著遗传分化；5个采样群体可以划分为3个种群。中性检验和核苷酸不配对分布显示，各种群均未经历过种群扩张事件。 相似文献
6.
为了解南海北部蓝圆鲹(Decapterus maruadsi)的群体遗传变异特征,本研究利用线粒体DNA Cyt b基因部分序列对9个群体共203个个体进行群体遗传多样性和遗传结构分析.结果显示:在722 bp长的Cyt b部分序列中,共检测出52个多态位点,定义25个单倍型;群体的单倍型多样性(h)为0.577±0.036,核苷酸多样性(π)为0.001 55±0.001 12,整体遗传多样性呈中等偏低水平,其中雷州半岛和海南岛以东5个群体的遗传多样性水平明显高于以西的4个北部湾群体.单倍型系统发育树和网络图均未表现出与地理位置相对应的谱系结构,单倍型网络图呈以主体单倍型为中心的星状结构.群体间的Fst值为-0.077~0.018,且统计检验均不显著(p0.05).分子方差分析(AMOVA)表明,遗传变异全部来源于群体内个体间.Tajima's D值和Fu's Fs值均为显著负值,核苷酸不配对分布呈明显的单峰分布.南海北部蓝圆鲹群体约在29 000a前可能发生过扩张事件,导致遗传多样性呈现高h、低π模式;9个群体间的遗传分化并不显著,符合是一个随机交配种群的假设,但9个群体的遗传多样性水平却表现出明显的地理趋势,提示将南海北部蓝圆鲹作为单一种群进行渔业管理需持谨慎态度. 相似文献
7.
《应用海洋学学报》2015,(3)
通过对印度尼西亚蓝碧海峡3个澄黄滨珊瑚(Porites lutea)地理群体(YM、YN、YS)的79个样本核糖体RNA转录单元内间隔区ITS基因(包括ITS1区和ITS2区)片段进行克隆、测序,探讨澄黄滨珊瑚的群体遗传多样性和遗传分化.结果表明:79条序列共获得63个单倍型,3个群体呈现出高的单倍型多样性(Hd=0.991 56)和高的核苷酸多样性(Pi=0.026 81).Tajima'D检验、Fu's Fs检验和岐点分布检验(mismatch analysis)推测种群经历了群体扩张事件.单倍型邻接关系树和单倍型网络图表明澄黄滨珊瑚群体没有明显的地理谱系结构.分子方差分析(AMOVA)表明群体间遗传变异占1.22%,群体内遗传变异占98.78%.群体间固定指数(Fst)的绝对值为0.012 2,表明群体间遗传分化较弱.各群体间的基因流值均大于4,说明澄黄滨珊瑚在当地群体间随机交配,基因交流十分充沛,各珊瑚群体间没有地理隔离,可以互相作为造礁珊瑚修复用的来源补充地. 相似文献
8.
为了解长江口及其邻近海域鮸鱼(Miichthys miiuy)的群体遗传多样性,采用线粒体COⅠ基因测序,对长江口(崇明)及邻近海域(舟山)2个鮸鱼群体的遗传变异进行了分析。结果表明,599 bp的COⅠ序列中包含22个变异位点,其中简约信息位点7个。60个个体中,共定义了20个单倍型,平均单倍型多样性指数(Hd)为0.676 8±0.069,核苷酸多样性指数(Pi)为0.002 29±0.000 37,表现为高单倍型多样性和低核苷酸多样性。分子方差分析(AMOVA)表明99.12%的遗传变异出现在种群内,仅有0.88%出现在种群间。群体间的遗传分化系数为FST=0.008 83(P0.05),2个群体间无显著遗传分化。NJ系统树显示,2个地理来源的单倍型没有明显的地理群聚和谱系结构。中性检验和碱基岐点分布(Mismatch distribution)分析结果表明鮸鱼群体可能发生过种群扩张事件。研究结果可为鮸鱼渔业资源的合理开发和利用提供必要的参考。 相似文献
9.
为研究洪泽湖河蚬种群遗传多样性及其遗传结构, 采用线粒体细胞色素氧化酶Ⅰ基因(COI) 作为分子标记, 采用PCR 扩增洪泽湖4 个河蚬群体(顾勒河GLH、临淮LH、蒋坝JB 和高良涧GLJ) 的COI 基因片段并进行了序列测定和分析。结果表明, 614bp 长度的核苷酸片段中, 碱基A+T 的平 均含量为65.0%, 明显高于G+C 的含量(35.0%).共检测到73 个多态位点, 多态位点比例为11.9%, 77 个个体中共获22 个单倍型(GenBank 登录号: KM659000-KM659021), 其中包括3 个共享单倍型, 4 个群体的平均单倍型多样性指数h 为0.889, 平均核苷酸多样性指数π 为0.04499, 平均核苷酸差异 数K 为27.622, 其中蒋坝群体的遗传多样性最高, 顾勒河群体的遗传多样性最低。22 个单倍型间的 Kimura 2-paramter 遗传距离为0.002-0.100, 平均遗传距离为0.0514.NJ 法构建的分子系统树显示 22 个单倍型聚为2 个分支。4 个群体间的遗传距离达0.03729-0.04969, 基于群体间遗传距离构建的 NJ 系统树中, 高良涧群体和顾勒河群体聚为一支, 蒋坝群体和临淮群体聚集为一支。AMOVA 分析 表明, 洪泽湖河蚬四群体间总遗传分化系数Fst 为0.06325(P>0.05), 93.67%遗传变异存在于群体内部, 6.33%变异存在于群体间。中性检验结果和歧点分布图显示, 洪泽湖河蚬种群大小保持稳定, 未经历 明显的种群扩张。 相似文献
10.
花斑蛇鲻(Saurida undosquamis)是一种重要的底层经济鱼类, 本研究利用线粒体控制区(D-loop区)序列分析了中国近海分布的花斑蛇鲻的遗传结构和遗传多样性, 一共测定了6个地理群体129尾样本的D-loop区全序列。结果显示, 全长为921bp的序列包含71个多态性位点, 共检测到101个单倍型。花斑蛇鲻总体呈现很高的单倍型多样性(0.9873 ± 0.0048)和较低的核苷酸多样性(0.0132 ± 0.0067)的特征。基于邻接法构建的单倍型系统发育树的拓扑结构很浅, 没有形成分化明显的支系。单倍型在各个地理群体中的分布呈分散交叉状态, 表明地理群体间没有显著的遗传分化。6个群体的分子方差分析显示, 花斑蛇鲻绝大部分的遗传变异(99.87%)来源于群体内的个体之间, 而群体间的变异仅占0.13%。大部分地理群体之间的遗传分化指数(FST)均很小, 揭示了群体间的基因交流很频繁, 存在高度的遗传同质性。这些研究结果表明中国近海的花斑蛇鲻遗传多样性丰富, 没有明显的遗传分化, 是一个随机交配群, 可以作为同一个渔业单元来管理。 相似文献
11.
Quentin Hanich 《Marine Policy》2012,36(2):327-332
The Western and Central Pacific Ocean is home to the world's most productive tuna fisheries, with the majority of tuna catches occurring inside the exclusive economic zones (EEZs) of the region's developing coastal States. It is important that these fisheries are managed effectively throughout their range, both within and between EEZs and on the high seas. Unrestrained exploitation in a particular EEZ or on the high seas has the potential to significantly impact on catches elsewhere with potentially devastating consequences for developing coastal States, some of which have few alternate resources. The Western and Central Pacific Fisheries Commission (WCPFC) was established in 2004 to manage the region's highly migratory tuna fisheries. However, the WCPFC has since repeatedly failed to adopt conservation and management measures that are sufficient to meet the WCPFC's conservation and sustainable use objectives. This paper analyses catch data from the WCPFC and suggests that the weak position of bigeye (in a strategic political context), the unwillingness of members to compromise their interests and the lack of a transparent framework for distributing the burden of conservation are key factors in the WCPFC's failure to adopt sufficiently strong conservation and management measures. 相似文献
12.
On 1 December 2007, eight ‘Small Island Developing States’ in the Western and Central Pacific Ocean implemented a management regime restricting the total number of days fished by tuna purse seine vessels within their waters, commonly referred to as the Vessel Day Scheme (VDS). The VDS is seen as one component of management arrangements to reduce fishing mortality on bigeye and yellowfin tuna, constrain fishing effort, and increase the rate of return from access fees by Distant Water Fishing Nations. 相似文献
13.
印度洋中西部大眼金枪鱼年龄与鱼体脂肪含量的关系 总被引：2，自引：0，他引：2
本文根据2012年10月—2013年3月在印度洋中西部海域金枪鱼延绳钓渔业调查所获得的样本,利用其脊椎骨鉴定了334尾大眼金枪鱼(Thunnus obesus)的年龄,并利用鱼类脂肪含量仪测定了其肌肉的脂肪含量,进而对年龄与脂肪含量的关系进行了研究。结果表明样本金枪鱼的特征如下:(1)年龄组成为1—9龄,其中4—6龄比例最大,约占样本总数的66.4%;(2)脂肪含量范围为3.1%—29.8%,平均为13.4%,优势范围在7.0%—17.0%之间,其中13.0%—17.0%的比例最高达51.4%;(3)通过比较不同年龄组的脂肪含量发现,鱼体脂肪含量1—3龄随年龄增加而下降。4—5龄脂肪含量较高,6龄急剧下降到最低,7—9龄又呈升高的趋势;(4)雌性和雄性大眼金枪鱼的新陈代谢变化无明显差异,雌性比雄性的性成熟年龄要早1年左右,雌性3—4龄时性成熟,而雄性为4—5龄时性成熟;(5)脂肪含量的变化可能与大眼金枪鱼生长、繁殖、衰老等过程中的新陈代谢变化相吻合。 相似文献
14.
中西太平洋延绳钓黄鳍金枪鱼渔场时空分布与温跃层关系 总被引：3，自引：2，他引：1
为了解热带中西太平洋延绳钓黄鳍金枪鱼(Thunnus albacares)适宜的温跃层参数分布区间,采用Argo浮标温度信息和中西太平洋渔业委员会(The Western and Central Pacific Fisheries Commission,WCPFC)的黄鳍金枪鱼延绳钓渔获数据,绘制了热带中西太平洋月平均温跃层特征参数和月平均CPUE的空间叠加图,用于分析热带中西太平洋黄鳍金枪鱼中心渔场时空分布和温跃层特征参数间的关系。分析结果表明:热带中西太平洋温跃层上界深度、温度具有明显的季节性变化,而温跃层下界深度、温度季节性变化不明显,黄鳍金枪鱼中心渔场分布和温跃层季节性变化有关。全年中心渔场的位置分布在温跃层上界深度高值区域,随温跃层上界深度高值区域季节性南北移动。在新几内亚以东纬向区域(5°N~10°S,150°E~170°W)上界深度值全年都在70~100m之间,全年都是延绳钓黄鳍金枪鱼中心渔场。中心渔场上界温度多在26℃以上,但是在上界温度超过30℃区域,CPUE值较小。中心渔场主要分布在温跃层下界深度两条高值带之间区域,在温跃层下界深度超过300m和小于150m区域,CPUE值均偏低。中心渔场主要分布在下界温度低于13℃区域,下界温度超过17℃难以形成中心渔场。频次分析和经验累积分布函数计算其适宜温跃层特征参数分布,得出中西太平洋黄鳍金枪鱼适宜的温跃层上界温度和深度分别是27~29.9℃和70~109m;适宜的温跃层下界温度和深度分别是11~13.9℃和250~299m。文章初步得出中西太平洋黄鳍金枪鱼中心渔场温跃层各特征参数的适宜分布区间及季节变化特征,为我国金枪鱼实际生产作业提供技术支持。 相似文献
15.
Adam Langley Andrew Wright Glenn Hurry John Hampton Transform Aqorua Len Rodwell 《Marine Policy》2009
Today, the tuna fishery of the western and central Pacific is one of the world's largest fisheries. Annual catches exceed 2 million mt—approximately 50% of the global tuna catch—with an estimated landed value of USD 3 billion (in 2005). The fishery expanded rapidly from the mid 1980s, following the development of the purse-seine fishery. From the mid 1990s, it was recognised that a Regional Fisheries Management Organisation was required to facilitate cooperation in the management of the resource. Following almost a decade of negotiations and planning, the Western and Central Pacific Fishery Commission (WCPFC) was established in 2004. During the interim period, stock assessments for the key tuna species were developed and revealed that for two species (yellowfin and bigeye tuna) there was concern regarding the increased levels of fishing mortality. However, declarations and resolutions calling for restraint in the expansion of fishing effort were largely unheeded over the last decade and, to date, the WCPFC has been unable to introduce any measures to effectively reduce (or limit) the level of fishing mortality on yellowfin and bigeye tuna. This paper proposes a number of mechanisms for improving the performance of the WCPFC with respect to meeting the conservation and management objectives of the commission and argues that Pacific Island nations need to collectively take the lead to ensure the effective management of the resource. 相似文献
16.
《Marine Policy》2014
Tuna fisheries in the Western and Central Pacific Ocean are among the most valuable resources in the region. These fisheries, worth an estimated $4.1 billion each year, play a pivotal role in supporting incomes and development goals in the region. However, due to the twin, and potentially inter-related effects of harmful fishing practices such as the use of fish aggregating devices, overcapacity, and fisheries subsidies, many of these tuna fisheries are currently at risk of over-exploitation—putting the livelihoods of countless local fishers at risk. This study finds that government fisheries subsidies in the region represent 37% of the ex-vessel value of tuna fisheries in the region. Fuel subsidies are estimated at US$ 335 million and non-fuel subsidies are estimated at US$ 1.2 billion for the year 2009. Developed countries are responsible for more than half of the subsidies spent in the predominantly developing region, underlying the fact that the majority of tuna value extracted from the national waters of developing countries in the region benefit larger, developed countries. The total resource rent, or return to society, from tuna fisheries, once adjusted for subsidies is a net negative US$750 million in 2009. Fisheries subsidies are enabling foreign fleets to operate at sub-market rates, putting local fleets out of competition for their own fishery resources. 相似文献
17.
The Western and Central Pacific Ocean (WCPO) tuna fishery is an important global food resource, and the economies of many Pacific Islands Countries (PICs) rely heavily on tuna industries. This paper proposes that governance by PICs is the key to improving the sustainability and profitability of tuna industries in the region. ‘Governance’ is usually used to refer to corruption, but here is interpreted more broadly to encompass the whole process by which decisions regarding public life are made and enacted, by government and also civil society. Argument is supported by empirical material from an interview study with stakeholders and a survey of reports. 相似文献
18.
鲣Katsuwonus pelamis广泛分布于各大洋热带和亚热带海域,其中以中西太平洋资源量最为丰富。综合评价环境因子对鲣鱼资源量的影响,构建科学的资源预报模型可为我国可持续合理开发该鱼种提供参考。本研究利用1998—2013年中西太平洋渔获量数据,以单位捕捞努力量渔获量(CPUE)为资源相对丰度指标,利用灰色关联方法分析鲣鱼资源相对丰度与环境因子之间的关联度,选取合适的环境因子,并基于不同环境因子构建不同的灰色预测模型对鲣鱼资源相对丰度进行预测,比较选择最优模型。结果表明, 中西太平洋鲣鱼的产量逐年递增,而CPUE在年间有着较大的波动。灰色关联分析认为,海表面温度与CPUE的平均关联度最大,其次为Nino3.4区海表温度距平值,其他的环境因子与CPUE的关联度较小。基于多环境因子的预测模型中,包含所有因子(海表面温度、海表面高度、叶绿素质量浓度a和Nino3.4区海表温度距平值)的模型M1有着最佳的拟合效果,实际值与预测值的相对误差为6.475 2,相关系数为0.687 4;而基于单一环境因子的预测模型中,去除11月SST数据的模型S2有着最佳的拟合效果,实际值与预测值的相对误差为7.419 2,相关系数为0.791 0。相比多环境因子的预测模型,单一环境因子预测模型有着较高的稳定性,实际值与预测值直接相关性也较高,可以作为中西太平洋鲣鱼资源相对丰度预报的最优模型。 相似文献
19.
Previous work on identifying opportunities for Pacific Island countries to improve the economic returns from their tuna resources in the Western and Central Pacific Ocean (WCPO) has not generally included articulation of aspirations from Islanders themselves. However, generating such an understanding is increasingly important as these countries assert their positions in regional fisheries policy making. This study analyses the self-identified aspirations of industry and government representatives from six Pacific Island countries and finds a wider diversity of attitudes, strategies and success than is generally recognised. Implications for negotiations in the WCPFC are then discussed. 相似文献
20.
In order to improve the forecasting ability of the fishery forecast model for the longline bigeye tuna (Thunnus obesus), we proposed a marine environment feature extraction method based on deep convolutional embedded clustering (DCEC), combined with generalized additive model (GAM) for forecasting the longline bigeye tuna fishing grounds in the Southwest Indian Ocean. We used the MODIS-Aqua and MODIS-Terra sea surface temperature (SST) three-level inversion image data (in days) from January to December in 2018 at 0.041 6°×0.041 6° to construct a DCEC model, determined the optimal number of clusters based on the Davies-Bouldi index (DBI), and extracted the category feature value (FM) of each month’s sea surface temperature (SST); we used monthly 1°×1° bigeye tuna longline fishery data from January to December in 2018 generated from the Indian Ocean Tuna Commission (IOTC), and calculated the catch per unit effort (CPUE); we matched the monthly category feature value FM and the monthly average value of Chl a concentration with the CPUE data to construct an improved GAM; we matched the monthly average SST, the monthly average Chl a concentration and CPUE data to build a basic GAM; we used the joint hypothesis test (F test) to verify the influence of model explanatory variables; we used akaike information criterion (AIC), mean square error (MSE), and draw the frequency distribution diagrams and box diagrams of measured and predicted values, etc., to analysis the improvement effect of the improved GAM compared to the basic GAM. The results showed that: (1) the category feature value (FM) extracted based on the DCEC model could better reflect the temporal and spatial dynamic characteristics of SST in the Southwest Indian Ocean, and was related with the climatic conditions, monsoon conditions, and hydrological characteristics in the Southwest Indian Ocean; (2) the factor interpretation of FM was higher than that of the monthly average SST in GAM, which means FM had more significant impact on the CPUE of bigeye tuna. The high catch rate was concentrated in the areas where the FM category was 2, 10, 24 with intersections between the warm and cold currents; (3) the AIC of the improved GAM was reduced by 9.17% than that of the basic GAM and MSE of the improved GAM was reduced by 26.7% than that of the basic GAM; the frequency distribution of the CPUE logarithmic value predicted by the improved GAM was closer to the normal distribution, and the high frequency distribution interval was closer to that of the measured value; the scatter plot showed that the CPUE predicted by the improved GAM had a significant correlation with the measured CPUE, with r equaled to 0.60. This study proves the effectiveness of the DCEC model in extracting marine environmental features, and can provide a reference for the further study on the bigeye tuna fishery forecast. 相似文献