Acoustic and egg-production estimates of South African anchovy biomass over a decade: comparisons, accuracy, and utility     

Hampton  Ian 《ICES Journal of Marine Science》1996,53(2):493-500

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Sub-Lethal Effects of Elevated Concentration of CO<Subscript>2</Subscript> on Planktonic Copepods and Sea Urchins   总被引：2，自引：0，他引：2  

Haruko Kurihara  Shinji Shimode  Yoshihisa Shirayama 《Journal of Oceanography》2004,60(4):743-750

Data concerning the effects of high CO₂ concentrations on marine organisms are essential for both predicting future impacts of the increasing atmospheric CO₂ concentration and assessing the effects of deep-sea CO₂sequestration. Here we review our recent studies evaluating the effects of elevated CO₂ concentrations in seawater on the mortality and egg production of the marine planktonic copepod, Acartia steueri, and on the fertilization rate and larval morphology of sea urchin embryos, Hemicentrotus pulcherrimus and Echinometra mathaei. Under conditions of +10,000 ppm CO₂ in seawater (pH 6.8), the egg production rates of copepods decreased significantly. The survival rates of adult copepods were not affected when reared under increased CO₂ for 8 days, however longer exposure times could have revealed toxic effects of elevated CO₂ concentrations. The fertilization rate of sea urchin eggs of both species decreased with increasing CO₂ concentration. Furthermore, the size of pluteus larvae decreased with increasing CO₂ concentration and malformed skeletogenesis was observed in both larvae. This suggests that calcification is affected by elevated CO₂ in the seawater. From these results, we conclude that increased CO₂ concentration in seawater will chronically affect several marine organisms and we discuss the effects of increased CO₂ on the marine carbon cycle and marine ecosystem. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

An application of the annual egg production method to estimate the spawning biomass of cod (Gadus morhua L.), plaice (Pleuronectes platessa L.) and sole (Solea solea L.) in the Irish Sea   总被引：1，自引：0，他引：1  

Armstrong  M. J.; Connolly  P.; Nash  R. D. M.; Pawson  M. G.; Alesworth  E.; Coulahan  P. J.; Dickey-Collas  M.; Milligan  S. P.; O'Neill  M. F.; Witthames  P. R.; Woolner  L. 《ICES Journal of Marine Science》2001,58(1):183-203

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Fecundity variation in Icelandic summer-spawning herring and implications for reproductive potential   总被引：2，自引：0，他引：2  

Oskarsson  Guthmundur J.; Taggart  Christopher T. 《ICES Journal of Marine Science》2006,63(3):493-503

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几种动物精卵识别机制     

刘慧慧  李太武  苏秀榕 《海洋湖沼通报》2004,200(1):16-21

动物受精是指两性配子细胞相结合生成合子的过程,亲代通过受精将遗传物质传给子代,它是衔接亲代与子代的桥梁,保持了物种的延续.精卵识别是受精的起始步骤,是指配子细胞通过各自表面的受精蛋白--糖蛋白类物质的特异性相互作用识别并结合,完成受精过程.本文着重介绍目前研究比较清楚的小鼠、猪、海胆和鲍等的精卵识别机制,比较了哺乳动物和无脊椎动物之间的联系和差别,进一步说明不同动物通过各自性细胞表面的糖蛋白完成精卵识别过程,并由相应糖蛋白的不同组成和结构决定了该识别过程的特异性.  相似文献   

超远缘鱼类—斑马鱼和泥鳅—受精卵的激光融合   总被引：2，自引：0，他引：2  

张闻迪  赵白  姚纪花  邹建华  王秋 《中国海洋大学学报(自然科学版)》1992,(3)

利用激光诱导方法对不同科鱼类,鲤科(Cyprinidae)的斑马鱼(Brachydanio Rerio)和鳅科(Cobitidae)的大鳞副泥鳅(Paramisgurnus dabryanus Sauvage)受精卵进行的融合实验结果表明:不同科间的鱼类受精卵可以融合并继续存活发育,有的可发育至初孵仔鱼。但是,其融合、发育表现出与亲缘关系较近的鱼卵的融合、发育有较大的差异。  相似文献   

卵生型鱼类卵子发育潜能评估研究进展     

赵艳飞  马爱军  王新安  孙志宾  温海深 《海洋科学》2016,40(8):157-167

鱼类卵子发育潜能(即卵子质量)是繁育工作所用卵子好坏的直接体现。雌性亲鱼性成熟过程中,卵巢内卵母细胞营养物质的积累及其正常减数分裂过程极易受外界环境影响,进而使亲鱼所产卵子可发育能力往往有较大波动,故提前预测亲鱼所产卵子的发育潜能,将对苗种繁育的风险防范及育苗产业健康发展带来积极影响。文章叙述了卵子及其成分特征,从卵子外形、卵质脂肪酸、氨基酸、蛋白、酶活等生化组成以及母源性RNA等角度对卵子质量研究现状做了概括,并对各自研究中存在的问题进行探讨。综上所述,从形态、脂肪酸、遗传物质等综合方面对卵质进行分析并建立其多元回归模型,将有助于找出影响卵质因素的关键信息;同时将卵质研究与家系构建相结合,后续跟踪、统计仔稚鱼至商品鱼这一生长阶段的生长参数,进行遗传评估,并最终确立具有最大经济效益的卵子参数,才是目前经济鱼类卵质标准研究需加强的方向。该研究将为今后卵生型鱼类卵子发育潜能预测方法研究提供科学依据,同时为鱼类繁育工作风险预判提供具实践性的方法资料。  相似文献   

福建太姥山晶洞碱长花岗岩地貌特征   总被引：2，自引：0，他引：2  

梁诗经  文斐成 《福建地质》2010,29(4):334-346

太姥山是东南沿海低山丘陵唯一的花岗岩峰丛-石蛋地貌,燕山晚期"A"型晶洞碱长花岗岩是太姥山造景岩石,北东东、北北西向断裂、裂隙及节理是控制山峰形态和规模的主要构造,风化剥蚀、降水侵蚀和重力崩塌是地貌形成的主要外动力作用,目前该地貌演化处于壮年早期阶段。其构造位置特殊、成景岩性独特,地貌类型丰富,是东南沿海晶洞花岗岩山岳地貌的典型代表和宝贵的地质遗迹。  相似文献   

2009年葫芦岛附近海域鱼卵仔稚鱼种类组成与数量分布     

赵静  张秀梅  卞晓东  吴忠鑫  高天翔  张沛东 《中国海洋大学学报(自然科学版)》2011,41(11):34-42

2009年5、8、10和12月,利用浅水Ⅰ型浮游生物水平和垂直拖网对葫芦岛海域鱼卵、仔稚鱼种类组成与数量分布进行了4个季度的调查。调查结果表明:4个季度共采到鱼卵44粒,仔稚鱼79尾,共鉴定出13个种,隶属于6目10科11属,其中有2种舌鳎类的鱼卵未能鉴定到种。优势种为赤鼻棱鳀(Thrissa kammalensis)、沙氏下鱵鱼(Hyporhamphus sajo-ri)、绯(Callionymus beniteguri)。春季垂直拖网采集到5粒鱼卵、8尾仔稚鱼。鱼卵、仔稚鱼的出现频率分别为25%和33.33%,平均密度分别为24.272和38.835ind/100m3;夏季水平和垂直拖网分别采集31粒鱼卵、47尾仔稚鱼和5粒鱼卵、24尾仔稚鱼,鱼卵、仔稚鱼的出现频率分别为100%、66.67%和20%、73.33%,平均密度分别为4.463、6.767ind/100m2和17.934、86.083ind/100m3;秋季和冬季都仅在水平拖网采到鱼卵,出现频率分别为10%和25%,密度分别为0.259和0.324ind/100m2。分析结果表明:随着季节的变化,暖水种、暖温种、冷温种间出现交替。春、秋、冬季鱼卵、仔稚鱼群落Margalef丰富度指数(D)、Shannon-Wiener多样性指数(H′)和Pielou均匀度指数(J′)平均值均较低,且各值均低于夏季,说明夏季种类结构相对其余3季稳定,多样性指数高、种类组成复杂、种间分布较均匀。本研究结果与该海域1998年同期(5、8月)调查结果在数量分布上有明显差异,鱼卵、仔稚鱼的种类组成与数量分布发生了显著变化。  相似文献   

What do egg size distributions in marine invertebrates tell us about validity of fecundity‐time models?     

Elena K. Kupriyanova 《Marine Ecology》2014,35(2):249-253

An early mathematical model of egg size evolution in marine invertebrates (American Naturalist, 1973a, 107 , 353) traded fecundity against development time and resulted in a U‐shaped optimality curve suggesting that only extremes of egg sizes should be evolutionary stable. It was later suggested that the model predicts a bimodal distribution of egg sizes and therefore can be tested by examining histograms of egg sizes. More recent fecundity‐time models (American Naturalist, 1997, 150 , 48; American Naturalist, 2000, 156 , 175) came up with predictions of intermediate optimal egg sizes; however, comparisons of optimality curves with histograms of egg sizes remained central to model testing. Here the question whether the bimodality assumption has any basis has been addressed theoretically. Simulation modeling and analysis show that egg size distributions generally do not match the optimality curves produced by fecundity‐time models and that the shape of predicted frequency distributions depends on both the optimality curve and other model parameters. Therefore, egg size frequency distributions alone cannot be used for model testing.  相似文献