Applications of stable isotope techniques in aquatic ecological studies

稳定同位素作为一种天然的示踪物,应用十分广泛,其在水域生态学中的应用也日益受到重视。生物同位素组成总是与其食物同位素组成相一致,能随食物的改变而相应地发生改变,是生物生存状况的理想指示物,为水域生态系统食物网结构与功能、物质流与能量流的研究提供了有力的技术支撑。在综评稳定同位素技术原理与方法的基础上,较为详细地对其应用于水域生态研究的理论基础与进展进行了总结。该方法的应用以水域中生产者同位素组成差异为前提,主要涉及确定食物来源、食物的贡献比例、营养级的确定、食物网结构的构建及鱼类等水生生物的洄游及迁移路线等方面,这些研究对了解生态系统的动态变化与外界环境对其影响具有重要意义。并对我国此类研究的前景和存在问题进行了探讨。Stable isotopes have been used in many research areas as natural labels and are becoming an important tool in aquatic ecological research.The theoretical basis and application of stable isotope analysis in aquatic ecology as well as its principle and method are reviewed in this paper.An organism's stable isotope ratios(δ()~(15)N and δ()~(13)C etc.) are an integration of the isotopic signatures of prey items that have been assimilated through time,the organism will come into isotopic equilibrium with its diet with the time to equilibrium depending on growth and tissue turnover rates.Stable nitrogen isotope ratios increase with trophic level by approximately 3‰ to 4‰;this provides a powerful analytical tool to quantify relative trophic position.In contrast,stable carbon isotope ratio changes very little with trophic level(0 to 1‰ enrichment per trophic level).Instead,stable carbon isotope values of organisms reflect the average δ()~(13)C of their diets.When an organism moves to a different habitat,its stable isotope ratios will change.From the stable ratios of the different habitats and the organism,we can judge the migration routine of the organism.Stable isotopes are often used to quantify the contributions of multiple sources to an organism.In general,the proportional contributions of n+1 different sources can be uniquely determined by the use of n isotope groups with linear mixing models based on mass balance equations.When there are n isotope groups and >n+1 sources,all possible combinations of each sources contribution can be obtained by a computer program(IsoSource),but the proportional contributions aren't unique.The above two cases presume that the proportional contribution of a source to an organism is the same for all isotope elements,while not all cases are so.An isotope element concentration-weighted linear mixing model was developed,whose quantified results are more reasonable,but only determined the proportional contributions of n+1 sources with n isotope groups.Prey sources,trophic level and prey proportional contributions etc.are basic information needed to construct aquatic ecosystem food web patterns and functions and material and energy flows,which are fundamental to understand the dynamic of ecosystems and effects of environment to the ecosystems.The prospect of such studies in China and some existing problems are also discussed国家自然科学基金重大资助项目(30490233)~

黄海带鱼、小带鱼RAPD和线粒体16S rRNA基因序列变异分析

对黄海带鱼、小带鱼各12个个体进行随机扩增多态DNA(RAPD)分析,对比多态位点比例、遗传多态度以及遗传距离,并构建Neighbor-joining系统树;通过PCR扩增出线粒体16SrRNA基因,纯化后直接测序,利用生物信息学方法进行序列分析和核苷酸变异比较,结合GenBank上大西洋叉尾带鱼同源序列构建UPGMA系统树.分析结果表明:(1)RAPD技术研究黄海带鱼和小带鱼的遗传多样性具有较高的灵敏度和检出率,带鱼的多态比例和遗传多态度均较小带鱼的低;(2)线粒体16S rRNA基因序列在分析这两物种遗传变异时表现出保守和变异的双重特性,种内变异极小而种间较大;(3)5个随机引物扩增出种特异的RAPD带,可作为种间分子鉴定标记;(4)研究证实带鱼和小带鱼是不同属的两个种,从而在基因水平上支持了Nelson分类系统的观点.国家重点基础研究发展规划资助项目(批准号:G19990437

基于线粒体Cytb基因的黄海、东海小黄鱼(Larimichthyspolyactis)群体遗传结构

采用线粒体dnA细胞色素b基因全序列分析技术研究了黄海、东海小黄鱼(lArIMICH-THyS POlyACTIS)的群体遗传结构.在所分析的9个取样点177个个体中,共检测到137个单倍型.9个群体呈现出高的单倍型多样性(H=0.956-1.00)和低的核苷酸多样性(π=0.0037-0.0058).单倍型邻接关系树的拓扑结构比较简单,没有明显的地理谱系结构.分子方差分析和fST显示小黄鱼的遗传变异均来自群体内个体间,而群体间无显著遗传分化.EXACT检验表明单倍型在两两群体间分布频率的差异是不显著的.中性检验和核苷酸不配对分析均表明黄海、东海的小黄鱼经历了群体扩张,扩张时间约为78—138kA前.研究结果表明,黄海、东海小黄鱼群体间具有高度的基因交流,是一个随机交配的群体.较强的扩散能力,黄海、东海的海洋环流以及近期的群体扩张可能是造成黄海、东海小黄鱼群体间遗传同质性较高的原因.国家自然科学基金(批准号:40776097);国家高技术研究发展计划(批准号:2009AA09Z401);青岛市科技计划(批准号:08-1-3-25-jch);中央级公益性科研院所基本科研业务费专项(批准号:2007-gy-06)资助项

中国海洋生物研究70年

随着中国"海洋强国"战略的提出,加快建设海洋类学科的发展成为历史必然,海洋生物是海洋不可分割的一部分,海洋环境和生物相互依存,相互作用,海洋生物研究重要性日益凸显。为纪念中国科学家在海洋生物领域的突出贡献,本文回顾了建国以来中国海洋生物相关的重要研究进展,梳理了中国科学家在海洋生物领域的突出贡献,系统总结并讨论了未来研究方向,抛砖引玉,希望籍此助推中国海洋生物研究的新高潮。国家自然科学基金项目(41876134,41876171)中国大洋矿产资源研究开发协会专项项目(DY135-E2-5-03)教育部长江学者特聘教授项目(T2014253

Feeding habit study of Anchovy(Engraulis japonicus)in the central and southern part of the Huanghai Sea with stable isotope techniques

根据2005年4~5月在黄海和长江口海域进行的春季底拖网调查,应用稳定同位素方法研究了黄海中南部鳀鱼(Engraulis japonicus)及其可能摄食饵料的碳氮稳定同位素比值,结果表明:(1)黄海中南部鳀鱼的食物组成为不同粒径的浮游动物、太平洋磷虾(Euphausia pacifica)和仔稚鱼,其中以粒径为500~900μm的浮游动物为主,贡献比例占61%~84%;仔稚鱼贡献比例占16%~21%,较传统胃含物方法分析的结果小;(2)黄海中部海域鳀鱼的碳氮稳定同位素比值平均值较南部海域高,原因可能与各海域的能量来源不同或存在微食物环有关,也可能与不同海域鳀鱼的能量转换途径不一样,即与食物链长短不一有关.Stable isotope techniques are commonly used to represent the trophic structure of aquatic systems.Based on the bottom trawl surveys in the central and southern part of the Huanghai Sea and adjacent sea area of Changjing River Estuary during the spawning season of Spring in 2005,we mainly focus on the stable carbon(13C/12C) and nitrogen isotope(15N/14N) ratios of anchovy and its potential food,such as zooplankton,Euphausia pacifica,larvae and juvenile fish,Leptochela gracilis,Loligo beka in order to acknowledge the feeding habit of anchovy.Application of δ13C and δ15N in dietary study depends upon the differentiation in the isotopic composition of various food sources.The δ13C and δ15N values of anchovy and its potential food indicated that its food sources in these areas were composed of zooplankton,Euphausia pacifica,fish larvae and juvenile fish.Especially,500~900 μm zooplankton was the most important dietary component for anchovy,accounting for 61%~84% of the total food by weight,the food proportion of the fish larvae and juvenile fish was 16%~21%,which was less than the results with the method of stomach content analysis;the variations in δ13C and δ15N values of anchovy in the central of the Huanghai Sea were higher than the area of southern part of the Huanghai Sea and adjacent sea of Changjing River Estuary,the reason were likely to difference between the sources of Anchovy energy or the length of the food chain in the different areas of the central and southern of Huanghai Sea and adjacent sea area of Changjiang River Estuary.Stable isotope analysis(δ13C and δ15N) can be a powerful tool in both identifying the source of organic matter that supports fish production and investigating food web remains untested using traditional dietary methods in the modern ecology.国家自然科学基金重大项目(30490233);; 国家自然科学基金项目(3037110430570293)资

Food competition of Engraulis japonicus and Thrissa kammalensis from the southern Yellow Sea in spring

根据南黄海鳀(Engraulis japonicus)和赤鼻棱鳀(Thrissa kammalensis)及其饵料的碳氮稳定同位素比值,采用IsoSource软件计算了两者饵料的质量贡献比。发现二者食物来源较为一致,其中仔稚鱼对鳀和赤鼻棱鳀的质量贡献率分别为42%~50%和53%~70%,是两者的首要能量与营养源。在获得食物贡献比的基础上,分别采用食物重叠指数法、聚类分析法和稳定同位素法3种方法,针对5种不同的摄食条件,依次对鳀与赤鼻棱鳀的食物重叠度进行计算。其中在饵料平均贡献比条件下,3种方法的计算结果相差不大,都在70%左右,计算偏差≤5%。研究结果表明,两者的食物竞争主要是针对仔稚鱼展开的,两者间存在显著的食物竞争关系。Stable isotopes have been used in many research fields as natural labels,and are becoming more and more appropriate option for aquatic ecological studies.An organism's stable isotope ratios(δ15N and δ13C,etc) are an integration of the isotopic signatures of preys that have been assimilated through time,the organism will come into isotopic equilibrium with its diets depending on growth and tissue turnover rates,the ratios can change with different food,are good labels of organism living conditions.According to the stable isotope ratio of an organism and its preys,we can judge its food composition.On the basis of the prey proportions of the Engraulis japonicus and Thrissa kammalensis determined by stable isotope technology.The proportions of all food sources showed that larvae and juvenile fish were the most important prey to E.japonicus and T.kammalensis,whose proportions were 42%-50% and 53%-70%,respectively.On the basis of food proportions,we calculated the prey overlap between the two fish species with three methods,diet overlap index,Cluster analysis and stable isotope technology,respectively.The mean result of each method was about 70%.There no significant difference among results of the three methods,with calculate error less than 5%.From the results of the research,we speculated that the larva and juvenile had the highest proportion,which was the main energy and trophic source of the two fish species.From the result of the research,we speculated the nitrogen stable isotope can used to calculate the food overlap of species.国家自然科学基金重大项目(30490233);; 国家自然科学基金面上项目(30570293);; 黄海水产科学研究所博士生启动基金(61200603

Genetic diversity in small yellow croaker (Pseudosciaena polyactis) by RAPD analysis

小黄鱼 (Pseudosciaenapolyactis)是我国近海重要经济鱼类之一。本文分析了采自黄海和东海 5个海区共计4 8个个体小黄鱼的随机扩增DNA多态性 (RAPD)。从 4 0个 10bp引物中选取 2 0个用于群体遗传多样性分析 ,共检测出 14 5个位点 ,其中 132个 (91.0 3% )显多态性。用Shannon多样性指数量化的平均遗传多态度为 1.93(1.5 0～ 2 .4 4 ) ,群体内和群体间的遗传变异比例分别为 6 9%和 31% ;群体间的平均遗传相似度和遗传距离分别为 0 .9139和 0 .0 86 1。用非加权配对算数平均法 (UPGMA)聚类分析的结果表明 ,所分析的 5个群体可分为 3个地理群系 ,从分子水平上支持了过去有关学者把黄海和东海的小黄鱼划分为北、中、南 3个地理群系的观点Pseudosciaena polyactis is a commercially important fish species which is widely distributed in the Bohai Sea, the Yellow Sea and the northern part of the East China Sea. Forty eight individuals of P. polyactis from five sampling areas in the Yellow Sea and the East China Sea were analyzed by random amplified polymorphic DNA (RAPD) markers to determine the genetic variation among and within the stocks. A total of 145 loci were amplified using 20 random primers, of which 132 loci (91.03%) were polymorphic. Genetic diversity quantified by Shannon index varied from 1.50 to 2.44 with an average of 1.93. Partition of genetic variation indicated that 69% was distributed within stocks and 31% among stocks. The average genetic similarity and genetic distance were 0.9139 and 0.0861, respectively. Cluster analysis by UPGMA indicated that these five stocks might be divided into three groups. Results of RAPD analysis suggested extensive genetic diversity exists in this species and the genetic divergence among stocks is relatively high. The UPGMA dendrogram showed that there existed three geographic populations of P. polyactis in the Yellow Sea and the East China Sea, which supports previous conclusions based on morphological and ecological methods.国家重点基础研究专项资助项目 (G19990 43 7

中国近海8种石首鱼类的线粒体16S rRNA基因序列变异及其分子系统进化

通过PCR扩增出中国近海石首鱼科(Sciaenidae)6属8个代表种的线粒体16S rRNA基因,纯化后直接测序.利用多个生物软件对序列变异和碱基组成进行分析,计算Kimura 2-parameter遗传距离、平均核苷酸变异数、平均每位点核苷酸替代数等遗传信息指数,并结合GenBank上大斑石鲈(Pomadasys maculates)同源序列构建UPGMA,NJ,ME和MP系统树.结果表明,叫姑鱼(Johnius belengerii)为最早分化的一枝,其次为黄姑鱼(Nibea albiflora)和白姑鱼(Argyrosomus ar-gentatus),而黄鱼亚科(包括大黄鱼(Pseudosciaena crocea)、小黄鱼(Pseudosciaena polyactis)、棘头梅童鱼(Collichthys lucids)、黑鳃梅童鱼(Collichthys niveatus)和鲵鱼(Miichthys miiuy))分化最晚,这支持了形态学得出的结论.在分子水平上明确了叫姑鱼亚科和黄鱼亚科的系统进化地位,并得出黄姑鱼比白姑鱼更早分化的新推论,但对于形态学上将白姑鱼和黄姑鱼归属于同一个亚科的结论还有待使用多个不同进化速率的基因加以分析考证.为探讨中国石首鱼类分子系统进化做了尝试,并就线粒体16S rRNA基因在该科鱼类系统进化研究的应用潜力进行了剖析.国家重点基础研究发展规划(批准号:G19990437);; 国家自然科学基金(批准号:30271027)资助项

Feeding habit of Erisphex potti from Changjiang Estuary and adjacent sea in spring

采用碳氮稳定同位素技术和聚类分析法对春季长江口及其邻近海域虻(Erisphex potti)的饵料组成、摄食随体长的变化进行研究,结果表明:(1)虻的食物由大于900μm的浮游动物、细螯虾(Leptochela gracilis)、太平洋褶柔鱼(Todarodes pacificus)、双喙耳乌贼(Sepiola birostrata)、火枪乌贼(Loligo beka)、日本枪乌贼(Loligojaponica)、脊腹褐虾(Crangon affinis)和仔稚鱼组成,优势饵料为浮游动物,其重量贡献率为69%~75%。(2)虻的食物组成及摄食量在体长为60mm时发生较大变化,脊腹褐虾、仔稚鱼及软体动物等饵料对体长大于60 mm的虻的贡献率增大,增幅为1%~12%。In order to assess the relative trophic importance of the spotted velvetfish in Changjiang Estuary and adjacent sea in summer,carbon(δ~(13)C) and nitrogen(δ~(15)N) stable isotope ratios were determined in spotted velvetfish and its potential food sources.Based on an organism's stable isotope ratios are an integration of the isotopic signatures of food sources that have been assimilated through time.The δ~(13)C and δ~(15)N values showed that the spotted velvetfish's food sources were composed of plankton >900 μm,Leptochela gracilis,common squid,Lantern cuttlefish,Beka squid, Common Japanese squid,larvae and juvenile and Japanese sand shrimp.plankton >900 μm was the most important food source,accounting for 69%-75% of the total food by weight.Food proportion of the spotted velvetfish varied among different classes of sizes.Cluster analysis dived the body lengths of the spotted velvetfish into two groups according to stable isotope ratios,>60 mm and 900 μm was 68%-87% to 75%-88% for the > 60 mm to 900 μm was the most important prey,while others were eaten occasionally by the spotted velvetfish.If the production of plankton >900 μm decrease in some cases,the spotted velvetfish would increase the other food proportion,sharing the large size food with other organisms,which would decrease the production of high trophic level organisms or shorten the length of food chain.国家自然科学基金重大项目(30490233);; 国家自然科学基金面上项目(30570293