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1.
许多海洋无脊椎动物在变成附着成体之前,有一个浮游幼体阶段。幼体的浮游生活短则几分钟。长达数月。一般来说,海洋无脊椎动物幼体的附着变态主要由外界环境因子和内源性因子控制,特别是外界环境因子对许多海洋无脊椎动物的幼体附着和变态起着极为重要的作用。  相似文献   

2.
中华绒螯蟹幼体资源生态及养殖生态学研究   总被引:2,自引:0,他引:2  
黄勃  堵南山  赖伟 《海洋科学》1999,23(1):39-40
中华绒螯蟹(Eriocheir sinensis)俗称河蟹,属短尾类十足目甲类动物[1],其幼体广泛分布于我国河口地区,主要生活在河口半咸水和海水中。亲蟹在河口区产卵,孵化后幼体营浮游生活,具有强烈的趋光性,并且表现为群聚特征,易被径流带离河口区。幼体发育到后期已基本到陆架区,大眼幼体变态为一期仔蟹后营底栖生活。营底栖生活的仔蟹背离陆架区往河口区移动而完成幼体的生长发育[2]。中华绒螯蟹在自然海域资源补充过程中主要采取r-对策,一只亲蟹一般可产卵5~90000粒,由于营浮游生活的幼体易被其他海洋…  相似文献   

3.
中国海多毛类动物区系研究的初步报告   总被引:1,自引:0,他引:1  
多毛类动物是海洋无脊椎动物中最大的类群之一,并且有着很重要的经济意义。成虫绝大多数营底栖生活,很多种类在软相的底质上分布非常稠密,因此它们在底栖动物的生物量中占了相当重要的地位;幼体主要营浮游生活,在沿岸的浮游生物中常可见到大量的多毛类幼体,这时它们即成为浮游生物主要的成分之一。  相似文献   

4.
中国沿海中华白海豚种群的分布区   总被引:1,自引:0,他引:1  
中华白海豚Sousa chinensis(Osbeck,1765)首先在我国发现,是我国沿海仅有的定居性海洋鲸豚类.本文根据中华白海豚目击事件和研究报道,分析了中华白海豚在中国的分布、种群隔离及其差异.认为我国南方福建、广东以南沿海为中华白海豚种群的主要分布区,明确指出我国沿海存在5个主要的中华白海豚种群栖息地.通过分析,划分出中华白海豚活动的边缘区和栖息地两个部分.由于中华白海豚种群不断缩小,在保护中华白海豚栖息地的基础上,加强对中华白海豚栖息地外的边缘区的保护显得尤为重要.本文分析将为科学划定中华白海豚保护区提供依据.  相似文献   

5.
大角玻璃钩虾Hyale grandicornis是我国沿海潮间带常见的藻栖甲壳动物, 但目前关于其与栖息海藻的作用关系极少报道。2016年2—5月在大亚湾岩礁潮间带采集了石莼Ulva lactuca和半叶马尾藻变种Sargassum hemiphyllum var. chinense海藻, 结果显示大角玻璃钩虾在两种海藻丛中均有分布, 其中在石莼藻丛中分布的钩虾个体数量、平均体长和平均体重均大于在半叶马尾藻藻丛中。在半叶马尾藻藻丛中, 大角玻璃钩虾种群的性比、抱卵雌性比例和幼体比例相对较高, 而性成熟体长、抱卵雌性体长和卵粒体积则相对较小。研究表明, 大角玻璃钩虾在两种海藻中的种群分布与繁殖特征存在着差异, 可能受到栖息海藻形态结构及其生境等因素的影响。  相似文献   

6.
中国海域已报道的约90种对虾中,半数具有经济价值。其中中国对虾、墨吉对虾和长毛对虾无论在捕捞还是在养殖业上都具有十分重要的地位。由于3种虾的形态非常相近,特别是在早期生活史阶段,它们的幼体和仔虾很难区分,因而给对虾种群补充、预报和其它有关研究造成困难。尤其在热带海域,对虾生殖季节重叠,幼体和仔虾的鉴别更加重要,各期仔虾的数量统计需以严格的形态鉴别作为依据。作者对三种对虾的幼体的形态,区别已有专文报道(Liu and Liu,1994)。本文深入细致地研究了中国对虾、墨吉对虾和长毛对虾仔虾的发育形态学,并进行了比较,使3种对虾的仔虾得以区别,并为今后的对虾生态学研究及资源管理奠定基础,提供依据。  相似文献   

7.
对海南岛海岸澄迈角沙滩的3个断面进行了潮间带生态调查。初步鉴定无脊椎动物32种,其中软体动物8种,甲壳类14种,多毛类8种,其它动物2种。优势的大型底栖动物有端足类的肢突跳钩虾Talorchestia brito,等足类的日本异浪漂水虱Excirolana japonica和双壳类的等边浅蛤Gomphina aequilatera。垂直分布可分为:(1)钩虾带,以肢突跳钩虾为特征种;(2)等足类带,以日本异浪漂水虱为特征种;(3)蛤-螺带,以等边浅蛤-(虫昌)螺Umbonium vestiarium为特征种。研究表明,沙滩底栖动物垂直分布主要受潮汐、底质、盐度和波浪的影响。  相似文献   

8.
夏季大亚湾大型底栖动物群落结构   总被引:1,自引:0,他引:1  
利用2013年8月在大亚湾海域进行的海洋生态调查所采集的底栖动物样品及环境参数,研究了夏季大亚湾海域底栖动物种类组成、数量分布、群落结构及其环境影响因子。结果表明,调查共采集到大型底栖动物153种,其中环节动物81种、软体动物37种、甲壳动物25种、棘皮动物6种、其他类动物4种;环节动物种数占总种数的52.94%,是构成大亚湾大型底栖动物的主要类群。优势种类为短吻铲荚螠和波纹巴菲蛤。底栖动物平均丰度和平均生物量分别为410ind·m~(–2)和84.83g·m~(–2)。等级聚类分析(CLUSTER)将大亚湾的底栖动物分为5个群落。相关性分析表明,影响夏季大亚湾底栖动物群落结构的主要环境因子为沉积物石油类。BIOENV分析表明,底栖动物种类丰度与有机质和重金属的铅、铜和镉等环境因素密切相关。  相似文献   

9.
浮游端足类??亚目(Amphipoda-Hyperiidea)是海洋浮游甲壳动物中比较重要的类别之一,它们不但常见而且是经济鱼类的良好饵料。有关此类海洋浮游动物的垂直分布,国外学者有较多研究结果发表,如Thurston (1976)和Shulenberger (1977)曾经分别作过较为详细的报道;国内学者也曾作过零星报道(李冠国、黄世玫,1964;郑重、郑执中等,1965 ;陈清潮等,1978)。 本文研究材料是中国科学院海洋研究所1978年5月底至7月初在东海的几个断面上(123°一129°E,26°30′-32°30′N),用大型浮游生物网采得的78 号垂直分层(0一50m, 50-100m, 100-250m, 250-500m, 500-1000m, 1000-2000m)样品。作者对样品中的端足类??亚目逐层分类计数,初步分析了其种数、总量及主要种的垂直分布特征,为今后进行浮游生物生态研究提供必要的参考资料。  相似文献   

10.
本文主要取材于1985—1986年长江口渔业资源试捕调查资料。研究结果表明,分布在长江口海区的虾类,由于受长江冲淡水径流的影响,形成三种生态型:(1)河口半咸水类型,如两种白虾;(2)低盐水类型,如葛氏长臂虾;(3)外侧次高盐水类型,如鹰爪虾和两种仿对虾。代表各生态型虾类,一般具有繁殖期较长的特点,其生命周期可为一年或一年多。虾类体长分布较为复杂,在当年生的幼虾生长期间,秋冬季虾群中常有幼虾和成虾混栖。因而,种群体长分布有两组群体并存。  相似文献   

11.
回顾海洋浮游甲壳类系统学研究的基础上,综述了生化水平和DNA(mtDNA和核DNA)水平的分子系统学研究现状。分子标记中DNA序列分析最为常用,其次是RFLP和RAPD分析,mtDNA主要应用于分类学、群体遗传学、种间分子进化和系统发育重建研究,而核DNA则应用于科以上较高阶元的系统发育和种内、近缘种间的遗传结构和遗传分化研究。最后对存在的问题和应用前景进行了展望。  相似文献   

12.
Abstract

Plankton includes the primary producers and consumers that are critical for healthy ecosystem function in the marine realm. My objective was to identify the major contributions of the Leigh Marine Laboratory to our broader understanding of planktonic assemblages. Significant contributions were made prior to 1990 on the ecology of larval fishes. From the 1990s the focus changed to the sensory biology of larval invertebrates and fishes, with a strong emphasis given to the role of reef sound in attracting potential settlers. Both early and post 1980s research has been highly influential in a paradigm shift away from passively drifting larvae that have little control over their fate. Important contributions have also been made on the dynamics of nutrient–phytoplankton interactions, larval development and aquaculture. Opportunities abound for future research on the dynamics of planktonic assemblages in shelf waters and in changing seas.  相似文献   

13.
The level of parental investment for larval nutrition may determine the life cycle in marine invertebrate species laying egg masses or capsules, where the food available for enclosed individuals would determine time and developmental stage of hatching. Most species show a unique type of larval development. However, few species are poecilogonous and combine more than one development type. Poecilogony, although scarcely studied, allows comparing different patterns of parental reproductive investment, without the phylogenetic effect of the species ancestral modes of development (phylogenetic inertia), to help to understand the factors determining life strategy evolution in marine invertebrates. The poecilogonous polychaete worm Boccardia wellingtonensis encapsulates and incubates its offspring, which then hatches as either planktotrophic larvae or benthic juveniles; while Boccardia chilensis shows a non-poecilogonous reproductive type, producing only planktotrophic larvae. In this work, we estimated the bioenergetic and biochemical composition of brooding and non-brooding females of B. wellingtonensis and B. chilensis to compare the costs of reproduction in these two species. Results showed that glucose, protein, lipid, and energy content were significantly higher in non-brooding than in brooding females of B. wellingtonensis; but also contained significantly more glucose, protein, and lipid than females of B. chilensis (in absolute and relative dry weight values). The poecilogonous species showed higher energy content previous to laying offspring. Our results support the idea that the evolution of a certain reproductive and life history traits in marine invertebrates is related to adaptations in the female's reproductive investment.  相似文献   

14.
Similarities in the marine fauna found off the coasts of southern Madagascar and KwaZulu-Natal Province (KZN), South Africa, led to the development of the ‘suitcase project,’ with the aim of establishing whether eddies that form off southern Madagascar may package and transport biological material across the Mozambique Channel, facilitating connectivity and gene flow. Meroplankton (larval stages of fishes and benthic invertebrates) were collected on the Madagascan shelf and along a transect through a cyclonic eddy in the Mozambique Channel. The samples were analysed using microscopy and DNA barcoding, seeking to identify species known to be common to both the southeast coast of Madagascar and the east coast of South Africa and thereby to reveal potential indicators of connectivity between these regions. The greatest zooplankton biovolume in the upper 200 m occurred on the shelf, followed by in the western part of the eddy and in the region outside the eddy to the west, and was lowest in the region outside the eddy to the east. The meroplankton were dominated by taxa of coastal origin and these were also most abundant on the shelf and in the western part of the eddy, with the lowest abundances in the region outside the eddy to the east. The findings show greater zooplankton biovolumes and larval abundances and the presence of reef-associated larval assemblages on the Madagascan shelf and along the transect through the cyclonic eddy, providing support for the suitcase hypothesis that planktonic organisms are entrained within eddies as they propagate south-westwards of the Madagascan shelf.  相似文献   

15.
Parasites, in particular trematodes (Platyhelminthes: Digenea), play major roles in the population dynamics and community structure of invertebrates on soft‐sediment mudflats. Here, we provide a list of the 20 trematode species currently known to infect molluscs, crustaceans and polychaetes from Otago Harbour (New Zealand) soft‐sediment intertidal areas, as well as information on their transmission modes, life cycles, andknown ecological impacts. Several of the host‐parasite species combinations recorded here are reported for the first time. We also provide DNA barcodes, based on sequences of the cytochrome oxidase subunit l (CO1) gene, for 19 of the 20 trematode species, to facilitate future identification of these parasites in marine ecological studies.  相似文献   

16.
赵峰  王子涵  曹玲  曾聪 《海洋科学》2023,47(11):97-109
黄东海是太平洋重要的边缘海,拥有丰富的海洋生物多样性资源,但在气候变化及人类活动的双重胁迫下,黄东海面临生物多样性衰退等问题,亟需加强保护。保护区网络被认为可有效防止或减缓人类活动和气候变化对生物多样性的负面影响,但连通性作为保护区网络的重要参数却很难直接测量。因此,本研究希望通过梳理已发表的黄东海间遗传连通性文献来揭示黄东海区域内的保护区是否形成网络。通过搜集已发表的137篇文献,共获得175个研究案例。超过半数的案例(65.71%)认为黄东海之间具有显著的遗传分化,这也意味着跨生态区群体间具有较低的遗传连通性。在总结影响因素时发现长江冲淡水、生境异质性、空间距离、进化过程、生活史(较短的浮游幼体期)、洋流等6个因素阻碍了黄东海群体间的遗传连通性,而洋流、生活史(较长的浮游幼体期)等2个因素促进了遗传连通性。进一步分析发现黄东海群体间的遗传连通性与空间距离呈显著的负相关,而与浮游幼体期呈正相关。因此,根据本研究结果,建议未来保护区网络建设应针对黄、东海生态区分别构建网络,在网络设计时应考虑保护对象的扩散能力及保护区间的空间距离。本研究不仅为构建涵盖黄东海的海洋保护区网络提供理论基础,...  相似文献   

17.
Most marine organisms are characterized by at least one planktonic phase during their life history, potentially allowing interconnection of populations separated by several hundred kilometers. For many years, the idea that marine species are genetically homogenous throughout their range of distribution, due to passive larval transport, has been a paradigm. Nowadays, a growing number of studies underline the existence of boundaries in the marine realm and highlight how larval dispersal is a complex process depending on biotic as well as abiotic factors. Marine fragmented habitats, such as atolls, mangroves and estuaries, are optimal systems for investigating the marine dispersion process under a metapopulation approach, since populations can be geographically defined a priori as opposed to those occupying open marine environments. Within this frame, the present paper investigates the population genetic structure and the demographic history of the mangrove crab Neosarmatium meinerti within the western Indian Ocean by partial sequences of the mitochondrial DNA cytochrome oxidase subunit I. A total of 167 specimens were sampled from six mangrove sites distributed along the East African coast, from Kenya to South Africa, also including a mangrove forest located on Mahé Island, Seychelles. A sharp genetic break between the mainland and the Seychelles is recorded, revealing the existence of two historically distinct groups that can be defined as independent evolutionary units. Gene flow along the East African coast appears to be high enough to form a single metapopulation, probably by means of stepping stone populations. Otherwise, this mainland metapopulation is currently under expansion through a gradual moving front from the subtropical toward the equatorial populations.  相似文献   

18.
Fish larvae abundance and distribution in the coastal zone off Terminos Lagoon and their relation to the environmental features of the Lagoon inlets were analysed (1986–87). The sampling grid consisted of 24 stations extending between 0·5 and 10 km off the Lagoon, including both Terminos Lagoon Inlets; El Carmen and Puerto Real. A total of 23 families and 43 species were identified. Highest larval abundance was registered during the rainy period (July and September) when the fluvial discharges favoured the planktonic development. The lowest larval abundance was recorded in the period of northern cold wind (January–March) when the fluvial discharges decreased. Bray-Curtis index defined two groups of stations, corresponding to each of the lagoon inlets, persisting throughout the year. The first one, ‘ El Carmen ’, was characterized by larvae of Engraulidae and Gobiidae; estuarine-dependent inhabitants. This group could be considered as a functional extension of the Lagoon to the sea. The second group, ‘ Puerto Real ’, was characterized by highest larval abundance of marine dwellers (e.g.Opisthonema oglinumandHarengula jaguana). This situation suggests that the Puerto Real Inlet could be the main entrance of marine fishes into the Lagoon. These results indicate that the coastal zone off Terminos Lagoon constitutes an important nursery area both for species spending part of their life cycle linked to this estuarine system, and for marine species that migrate towards the Lagoon, carried by local currents.  相似文献   

19.
海水甲壳类寄生性甲藻Hematodinium spp.研究进展   总被引:1,自引:1,他引:0  
寄生性甲藻Hematodinium是一类危害海水甲壳类的致病性寄生性甲藻,在世界范围内严重威胁了多种重要经济甲壳类的渔业生产。近年来,Hematodinium先后在我国浙江、广东沿海的锯缘青蟹、三疣梭子蟹、脊尾白对虾等重要养殖甲壳类中报道发现, 并已确定该寄生甲藻是近年来引起当地养殖青蟹“黄水病”、三疣梭子蟹“牛奶病”和脊尾白对虾大规模死亡的主要病原之一。本文结合作者近年来Hematodinium的研究成果,系统综述了国内外该寄生性甲藻的研究进展,包括其系统分类、生活史、传播途径、发生机制等;并针对目前该寄生性甲藻研究中存在的关键问题,结合我国相关研究的现状做出了分析和展望,以期为我国海水甲壳类寄生性甲藻发生的预防与控制提供理论依据和技术支持。  相似文献   

20.
海洋浮游介形类(Ostracods)是一类分布较广的小型甲壳动物, 在海洋碳循环中起重要作用。目前国内海洋浮游动物采样常使用505μm网目孔径的浮游生物网, 从而导致个体较小的介形类被忽略。文章根据2006年7—8月(夏季)和2006年12月—2007年1月(冬季)在南海西北部海域分别使用网目孔径为505μm和160μm浮游生物网采集的样品, 比较不同网目所获浮游介形类种类和丰度的差异, 分析介形类种类和丰度的分布特征, 探讨环境因素对其时空分布的影响。160μm网目采集的浮游介形类种类和丰度均高于505μm。基于160μm网目数据分析浮游介形类群落结构: 1) 鉴定浮游介形类32种, 其种数由近岸向外海递增, 等深线100m以浅海域的种数显著高于100m以深海域(p<0.01); 2) 夏季浮游介形类的丰度高于冬季, 夏季丰度高值区主要出现在雷州半岛东部和琼东近岸, 显著高于外海(p<0.05), 冬季介形类丰度分布较为均匀; 3) 优势种针刺真浮萤(Euconchoecia aculeata)是近岸高丰度的主要贡献种; 4) 介形类种数与温度和水深呈显著正相关, 丰度与叶绿素a浓度呈正相关, 而与温度和盐度呈负相关。夏季琼东沿岸上升流和粤西沿岸流有助于浮游介形类在雷州半岛和海南岛东部近岸海域形成较高的丰度, 最高达1252个·m-3。同时, 建议今后研究浮游介形类采用网目孔径小的浮游生物网进行采集以便全面评估其群落结构特征。  相似文献   

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