中国鱼类名录Ⅸ——Yu亚目、马Ba亚目、鲈亚目（部分）   总被引：1，自引：0，他引：1  

李明德  罗阳等 《海洋通报》2003,22(2):69-75

Yu亚目1科1属11种，马Ba亚目1科2属5种。鲈亚目（部分）记述23科。  相似文献   

中国多金属结核开辟区仔稚鱼的分布特征     

王春生  何宗玉  何德华  高爱根  杨俊毅 《海洋学研究》2002,20(2):31-39

利用 1 997年～ 1 999年“大洋一号”调查船在中国多金属结核开辟区用邦哥网所采集的样品 ,对仔稚鱼的种类组成、密度的平面分布和年间变化及其与环境因子的关系进行了研究。结果表明 :中国开辟区共有 2 2科 6 1种仔稚鱼 ,其中大洋性发光鱼类灯笼鱼科的种类最多 ,达1 7种 ,约占总种类数的 2 8% ,其次是钻光鱼科 (6种 )、金枪鱼科 (6种 )和拟白鲑科 (5种 ) ,分别约占总种类数的 1 0 %、 1 0 %和 8%。东、西两区的种类组成有较大的差异 ,共有种仅为 1 7种 ,东区种类数 (48种 )明显多于西区种类数 (3 0种 )。仔稚鱼的密度有明显的空间和时间变化 ,东区仔稚鱼的密度高于西区 ,东区 1 999年仔稚鱼的密度约为 1 997年的 5倍 ,西区 1 999年仔稚鱼的密度约为 1 998年的 3倍。仔稚鱼密度的年间变化可能与 El Nino事件有关  相似文献   

闽东北外海渔场捕捞中上层鱼类的渔具,渔法研究     

王芳灿 《台湾海峡》1995,14(4):413-417

本文分析了闽东北外海渔场资源特点，并就不同类型的拖网、围网渔具的适渔性对比试验进行了研究，认为以主机功率330.75kw及以上的拖网渔船，使用四片式疏目拖网和以主机功率183．75kw及以上的围网渔船，使用250m×150m的无囊灯光围网，于春、夏汛时在该渔场100m等深线附近海域能较有效地捕捞鲐鲹等中上层鱼类。  相似文献   

商事委托合同任意解除权的思考     

余珺 《成都信息工程学院学报》2008,23(3):340-344

中国现行合同法没有区别民事委托合同与商事委托合同,而统一赋予两者任意解除权,导致实践中商事委托合同因任意解除权的行使而产生了大量的纠纷。对赋予商事委托合同提出质疑,并从委托合同任意解除权之法理,委托合同之发展演变,商事委托合同之博弈性,商事委托合同之经济性以及商事委托合同任意解除权行使与权利滥用等诸多角度论述了赋予商事委托合同任意解除权的不合理性。  相似文献   

ELECTRON MICROSCOPE EVIDENCE OF VIRUS INFECTION IN CULTURED MARINE FISH     

孙修勤  张进兴  曲凌云 《中国海洋湖沼学报》2000,18(3):280-282

ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｒｅｃｅｎｔｙｅａｒｓ’ｒａｐｉｄｄｅｖｅｌｏｐｍｅｎｔｏｆｔｈｅｍａｒｉｎｅｆｉｓｈｃｕｌｔｕｒｅｉｎｄｕｓｔｒｙｉｎＣｈｉｎａｈａｓｂｒｏｕｇｈｔａｂｏｕｔｐｒｏｌｉｆｅｒａｔｉｏｎｏｆｖｉｒａｌｄｉｓｅａｓｅｓｉｎｔｈｅｉｎｄｕｓｔｒｙａｓｓｈｏｗｎｂｙｔｈｅｎｏｔａｂｌｙｆｒｅｑｕｅｎｔｏｃｃｕｒｒｅｎｃｅｏｆｄｉｓｅａｓｅｓｏｒｄｅａｔｈｓｏｆｔｈｅｍａｒｉｃｕｌｔｕｒｅｄｆｉｓｈ .Ｅｌｅｃｔｒｏｎｍｉｃｒｏｓｃｏｐｅｅｘａｍｉｎａｔｉｏｎｏｆｔｈｅａｆｆ…  相似文献   

电子商务产生和发展的理论思考     

杨羽 《成都信息工程学院学报》2000,15(4):279-284

分析了电子商务产生和发展的条件 ;提出在实践中发展电子商务时 ,世界范围内及我国尚需解决的问题 ;并从理论与实践两方面论证电子商务具有广阔前景。  相似文献   

Nocturnal fish utilization of a subtropical mangrove‐seagrass ecotone     

Neil Hammerschlag  Joseph E. Serafy 《Marine Ecology》2010,31(2):364-374

Whereas diel fish migration between mangrove and seagrass habitats has been recognized for decades, quantitative studies have focused mainly on diurnal patterns of fish distribution and abundance. In general, previous studies have shown that fish abundances decline with increasing distance from mangroves; however, evidence for such a pattern at night, when many fishes are actively feeding, is scarce. The present study is the first to report nocturnal fish abundances along a continuous distance gradient from mangroves across adjacent seagrass habitat (0–120 m). Here, we used nocturnal seine sampling to test the null hypothesis (based on diurnal studies and limited nocturnal work) that fish abundance would decrease with increasing distance from shoreline. We focused on species and life‐stage‐specific abundance patterns of Lutjanus griseus, Sphyraena barracuda, Archosargus rhomboidalis, and Haemulon sciurus. Results indicated that assemblage composition and structure differed significantly by season, likely influenced by temperature. However, within each season, the fish habitat use pattern at both the assemblage and species‐specific level generally failed to support our working null hypothesis. Species‐specific analyses revealed that, for most species and life‐stages examined, nocturnal abundance either did not change with distance or increased with distance from the mangrove‐seagrass ecotone. Our results suggest that analyses where taxa are grouped to report overall patterns may have the potential to overlook significant species‐ and stage‐specific variation. For fishes known to make nocturnal migrations, we recommend nocturnal sampling to determine habitat utilization patterns, especially when inferring nursery value of multiple habitats or when estimating fish production.  相似文献   

In two waters: contemporary evolution of lagoonal and marine white seabream (Diplodus sargus) populations     

Mercedes González-Wangüemert  Ángel Pérez-Ruzafa 《Marine Ecology》2012,33(3):337-349

Brackish water ecosystems are often exposed to wide variations in environmental variables, including temperature and salinity, which may cause strong selective pressures on organisms modifying the genetic patterns of species. The aim of this work was to test whether there is a ‘divergence-with-gene flow’ in coastal lagoon populations of white seabream (Diplodus sargus) (Ria Formosa, S Portugal and Mar Menor, SE Spain) respect to four marine populations, by using partial sequences of cyt b mitochondrial gene and information from nine microsatellite loci. Genetic diversity was highest in both coastal lagoons (Mar Menor and Ria Formosa) considering mitochondrial and nuclear markers. Although some of F_ST population pairwise comparisons were not significant, analyses of molecular variance (AMOVAs) detected differences between groups (coastal lagoon and marine) close to significance. Also, only two haplotypes (Cytb-17 and Cytb-18) were detected in both coastal lagoon sampling sites and these localities (Mar Menor and Ria Formosa) showed the highest number of singletons, some of them with a high number of mutations, as has been already described for other Mar Menor populations (Pomatochistus marmoratus and Holothuria polii). Also, several tests detected significant positive and balancing selection considering mtDNA and microsatellite data. These data support the hypothesis of selection as one of the drivers of the genetic differences found between coastal lagoon and marine populations. The life strategy adopted by Diplodus sargus in coastal lagoons allows it to decrease its mortality rate and improve the heritability of its genes. Also, the increase time spent in coastal lagoons with different temperatures and salinities favours the fitness selection and the maintenance of exclusive haplotypes and genotypes in coastal lagoon inhabitants favouring the ‘divergence-with-gene-flow’.  相似文献   

Skin toxins in coral‐associated Gobiodon species (Teleostei: Gobiidae) affect predator preference and prey survival          下载免费PDF全文

Barbara Gratzer  Eva Millesi  Manfred Walzl  Juergen Herler 《Marine Ecology》2015,36(1):67-76

Predation risk is high for the many small coral reef fishes, requiring successful sheltering or other predator defence mechanisms. Coral‐dwelling gobies of the genus Gobiodon live in close association with scleractinian corals of the genus Acropora. Earlier studies indicated that the low movement frequency of adult fishes and the development of skin toxins (crinotoxicity) are predation avoidance mechanisms. Although past experiments showed that predators refuse food prepared with goby skin mucus, direct predator–prey interactions have not been studied. The present study compares the toxicity levels of two crinotoxic coral gobies – Gobiodon histrio, representative of a conspicuously coloured species, and Gobiodon sp.3 with cryptic coloration – using a standard bioassay method. The results show that toxin levels of both species differ significantly shortly after mucus release but become similar over time. Predator preferences were tested experimentally in an aquarium in which the two gobies and a juvenile damselfish Chromis viridis were exposed to the small grouper Epinephelus fasciatus. Video‐analysis revealed that although coral gobies are potential prey, E. fasciatus clearly preferred the non‐toxic control fish (C. viridis) over Gobiodon. When targeting a goby, the predator did not prefer one species over the other. Contrary to our expectations that toxic gobies are generally avoided, gobies were often captured, but they were expelled quickly, repeatedly and alive. This unusual post‐capture avoidance confirms that these gobies have a very good chance of surviving attacks in the field due to their skin toxins. Nonetheless, some gobies were consumed: the coral shelter may therefore also provide additional protection, with toxins protecting them mainly during movement between corals. In summary, chemical deterrence by crinotoxic fishes seems to be far more efficient in predation avoidance than in physical deterrence involving body squamation and/or strong fin spines.  相似文献   

Temporal partitioning of microhabitat use among four juvenile fish species of the genus Diplodus (Pisces: Perciformes,Sparidae)          下载免费PDF全文

Daniele Ventura  Giovanna Jona Lasinio  Giandomenico Ardizzone 《Marine Ecology》2015,36(4):1013-1032

Timing, microhabitat selection and behavior from the onset of settlement to recruitment to the adult population of juvenile fishes of the genus Diplodus (Pisces: Sparidae) were investigated along a rocky coastline in the Central Mediterranean Sea. The settlement periods in Diplodus sargus and Diplodus annularis were concentrated in spring, between late May and early June, and the recruits leave the nursery grounds in late September–October. Juvenile fishes of Diplodus puntazzo and Diplodus vulgaris showed a partial time overlapping, sharing the same zones in winter and early spring, from February to May. Multiple correspondence analysis showed that sea breams settle in well‐defined habitats. The smallest juveniles of D. sargus and D. puntazzo settled primarily in the shallowest sheltered pebbly areas, located in sciaphilous crannies covered by red algae. Diplodus vulgaris settlers were observed on a wider range of substrata: rock on sand, gravel and pebbles without algal cover or large boulders, generally in deeper waters. The intermediate‐size juveniles of D. sargus, D. puntazzo and D. vulgaris showed a preference for rocky substrata with substantial algal cover, with arborescent structures (Phaeophyceae). Diplodus annularis juveniles showed high fidelity to seagrass beds (Posidonia oceanica). The home range increased over time in all species, highlighting a loss of substrate specificity: larger juveniles were even observed in deeper and different microhabitats outside nursery grounds. This study suggests that shallow infra‐littoral rocky communities with photophilic algae play a key role in recruitment of sparid fishes, affecting the distribution and abundance of juvenile fishes and therefore determining the renewal of populations and the structure of adult assemblages.  相似文献