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胶州湾鱼卵、仔鱼和稚鱼的分布 总被引：7，自引：0，他引：7
2003年1月-2004年1月在胶州湾海域逐月进行连续13个航次的调查,对胶州湾鱼卵、仔鱼和稚鱼的种类组成、丰度和主要种类的分布进行了研究。结果表明,采集到的鱼卵均为浮性鱼卵。鱼卵丰度最高值出现在8月(5.02粒/m3),次之为5月(4.97粒/m3)。共采集到仔、稚鱼10种,隶属9科10属,优势种为刺鱼叚虎鱼、斑鱼祭和玉筋鱼。根据出现的季节和出现时间的长短,将仔、稚鱼分为暖季类群、暖季短时类群和冷季类群三种类群。暖季类群较冷季类群占有明显的优势。暖季短时类群的种数、丰度和站位出现率都比较低。仔、稚鱼的丰度、种数的季节变化显著,最大值均出现在6月份,丰度是16.34尾/m3,种数为7种,与海水月平均温度的季节变化节律基本一致。 相似文献
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Seasonal differences in catches of leptocephali in the East China Sea and Suruga Bay, Japan 总被引：2，自引：0，他引：2
Gen Minagawa Michael J. Miller Yobuo Kimura Shun Watanabe Akira Shinoda Jun Aoyama Katsumi Tsukamoto 《Estuarine, Coastal and Shelf Science》2007,71(3-4):730-740
The species composition, distribution, and size of eel larvae, or leptocephali, caught near the continental shelf in subtropical and temperate regions of East Asia were compared between two seasons (May–Jun and Oct–Dec) to learn about the seasonality of reproduction of marine eels. There was greater species richness and evidence of spawning by more species of marine eels during the late autumn surveys in both the East China Sea (ECS) and in Suruga Bay along the east coast of Japan. Small leptocephali <10 mm TL and a wide range of sizes of various taxa were collected during both seasons along the outer edge of the continental shelf in the ECS, indicating that some marine eels may spawn there all year. The lack of small leptocephali during the spring survey in Suruga Bay suggested that most eels have a clear seasonal cycle of summer or autumn spawning at the higher latitudes of coastal Japan where there is much greater fluctuation of water temperature throughout the year than in the ECS. At lower latitudes such as in the ECS, and in tropical areas where water temperatures are higher and more constant, some marine eels may spawn all year round. 相似文献
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鱼类生长激素的异源表达、应用及安全性评价 总被引：3，自引：0，他引：3
鱼类生长激素对鱼的生长发育起着重要的调节作用，能促进鱼体快速生长，提高饵料转化率，在水产养殖业中具有重大应用价值。转生长激素基因鱼具有快速生长效应，可以缩短养殖周期，降低养殖成本和风险。鱼类生长激素基因异源表达体系的建立和发展，使获得大量廉价的鱼类生长激素产品成为可能，为鱼类养殖业新型饵料添加剂的研制开辟了新的途径。本文综述了转生长激素基因鱼和鱼类生长激素基因的异源表达两方面的研究及其安全性评价。 相似文献
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Ichthyoplankton in a southern african surf zone: Nursery area for the postlarvae of estuarine associated fish species? 总被引：1，自引：0，他引：1
The surf zone ichthyoplankton of Swartvlei Bay was studied between February 1986 and June 1987, with particular emphasis on its potential role as a nursery area for estuarine associated marine fish species. Larvae and/or postlarvae of 16 families were identified from the surf zone, with the Gobiidae, Soleidae, Sparidae and Mugilidae comprising 85·7% of all teleosts sampled. The postlarvae of several taxa (including the six most common species), which utilize the Swartvlei estuary as a juvenile nursery area, were abundant in the surf zone. Conversely, species which are common in nearshore marine waters as juveniles and adults, but seldom enter estuaries, totalled less than 8% of the surf zone ichthyoplankton assemblage.Larval and postlarval densities peaked during summer when water temperatures exceeded 19°C and the estuary mouth was open. Concentrations of ichthyoplankton were highest at those sampling stations closest to the estuary mouth during the summer period. Diel changes in total catches revealed no significant difference between day and night densities; but of the four major taxa, the Mugilidae and Sparidae tended to be more abundant during the day, the Gobiidae at night and the Soleidae showed no distinct pattern. Results from a 24 h sampling session indicated that tidal phase may also be important in governing ichthyoplankton abundance in the surf zone. 相似文献
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Mnica Susana Hoffmeyer Menndez María Clara Biancalana Florencia Nizovoy Alicia Mabel Torres Eduardo Ramn 《Estuarine, Coastal and Shelf Science》2009,84(3):181-392
This study focuses on the composition, abundance and distribution of ichthyoplankton in the inner shelf area off Bahía Blanca Estuary on the SW Atlantic Ocean during late spring. Eggs and larvae of Brevoortia aurea, Engraulis anchoita, Parona signata, Sciaenidae spp. – such as Cynoscion guatucupa and Micropogonias furnieri –, and Odontesthes argentinensis were found. Species richness was low probably as a result of season and shallow depths. Ichthyoplankton abundance reached values close to 10 000 per 10 m−3 (eggs) and 4000 per 10 m−3 (larvae) and displayed a spatial distribution pattern with maximum abundance values restricted to a band parallel to the coast. Differences between egg and larval patterns, probably derived from a different displacement and hydrodynamic behavior, were observed. Egg and larvae distribution patterns were found related with spawning areas and to directly depend on salinity and mesozooplankton. The larvae distribution pattern, in particular, was found to inversely depend on particulate organic carbon. In addition, the geographic location of egg and larvae maxima strongly coincided with a saline front reported for this area in springtime, thus suggesting a direct relationship with it. 相似文献
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Surveys were conducted in four seasons in the eastern Beibu Gulf from July 2006 to November 2007,to determine the ichthyoplankton composition,abundance,as well as environmental factors impacted on their spatiotemporal distributions.The fish eggs and larvae were sorted from 303 zooplankton quantitative samples,in which at least 1 order,60 families,31 genera and 61 species of fish eggs and larvae were identified.The species number was highest in summer whereas lowest in winter.With the most abundant fish egg (the average density was 2.41 ind./m 3),spring was the main spawning season,while the greatest mean density of fish larva was 1.35 ind./m 3 in summer.In the whole year around,fish eggs had the trends to aggregate in the nearshore of Guangxi coast,fish larvae were more abundant in the northern water.Relationships between fish eggs and larvae abundance and environmental factors were analyzed by using the Yield-Density model.The spatiotemporal distribution of ichthyoplankton in eastern Beibu Gulf was closely related to the Chl a concentration,and the optimal temperature,salinity and Chl a were 19.4-21.7 C,31.8-33.1 and 1.5-4.8 mg/m 3,respectively.Additionally,the distribution of fish larvae could be effected by ocean currents in summer and autumn. 相似文献
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