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连江西牛鱼道运行效果的初步研究 总被引：5，自引：0，他引：5
鱼道建设被认为是有效缓解水坝阻隔鱼类洄游的重要方法之一,而鱼道效果监测是评价其功能的重要环节。连江西牛鱼道是广东省第一座建立在水坝主体上的过鱼通道,为了解其运行效果,采用张网法和截堵法,２０１２年３－８月共６次对西牛鱼道的过鱼效果进行监测。研究表明,西牛鱼道共监测到鱼类３目、８科、３０属、３８种,以银鮈（Squalidus argentatus）、乐山小鳔鮈（Microphysogobio kiatingensis）、子陵吻鰕虎（Rhinogobit giurinus）等小型鱼类为优势类群。进入鱼道的鱼类呈现昼夜差异,上午集鱼效果要显著优于其他时间段;不同季节集鱼的种类和数量呈现较大差别,３－８月集鱼数量逐渐减少,集鱼种类数以５月最多。与国内外其他鱼道的过鱼效果比较,西牛鱼道能较好地发挥其功能。 相似文献
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鱼道是解决拦河筑坝阻隔鱼类洄游的重要手段之一。为了满足兴建峡江水利枢纽工程后洄游鱼类上溯的要求,保护赣江水生生态环境的完整性,减缓工程对鱼类种群遗传交流的影响,针对峡江水利枢纽实际情况制定了鱼道过鱼方式。鱼道采用垂直竖缝式结构设计,由上游鱼道(出口段)、坝体过鱼孔口、下游主、副鱼道(进口段)、集鱼系统及连接段组成,设计主要过鱼季节为4-7月,流速0.7~1.2 m/s。采用仪器监测与人工观察相结合的方式对峡江鱼道过鱼效果进行了初步监测。监测结果显示:2017年监测到过鱼总数67.8万尾,其中上行占41.67%;期间共监测到22种鱼类,共计4目、7科、18属,以小型鱼类为主,如贝氏(Hemiculter bleekeri)、三角鲂( Megalobrama terminalis)、银鲴(Xenocypris argentea)、银鮈(Squalidus argentatus);不同季节过鱼数量不同,其中以二季度最多,占总数49.17%,过鱼数量以7月最多;过鱼数量昼夜差别大,以上午10:00至下午16:00是过鱼数量最多;与国内其他鱼道相比,峡江鱼道过鱼数量较多,过鱼效果显著。 相似文献
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为检验流溪河水厂坝建立的丹尼尔式鱼道试点工程效果,在2015-2016年鱼道主要过鱼时段4-10月,利用张网法逐日监测。结果显示,鱼道取样共采集鱼类906尾,隶属于3目、8科、32属、34种,体长范围5～74cm,优势种为尼罗罗非鱼(Tilapia niloticus)(数量比51.10%)、歺又鱼(Hemiculter leucisculus)(16.23%)、唇鱼骨(Hemibarbus labeo)(8.17%)、银鮈(Squalidus argentatus)(6.73%)、东方墨头鱼(Garra orientalis)(1.55%),以定居型鱼类为主,未见河口洄游性鱼类。水温与上游水位是影响鱼类种类时间分布的主要环境因素。聚类分析表明,6月过鱼群体的种类和数量独成一类,与其他月份鱼类群体最不相似。虽然Shannon多样性指数在5月和6月分别为2.068和1.719,但总体偏低(1.451±0.535),而Margalef丰富度指数差别较小,表明不同鱼类对鱼道入口的感应存在种间差异,推测是由工程全段翻滚闸门下泄水流导致鱼道入口不易发现所致。研究表明,丹尼尔式鱼道试点工程效果较好,为该河段的绝大部分鱼类提供了上溯通道,对流溪河构建整体过鱼设施体系起到了良好的示范作用,有助于流溪河生态系统的健康与恢复。 相似文献
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鲢幼鱼游泳能力及游泳行为的试验研究 总被引：1，自引：0，他引：1
为了探究四大家鱼的游泳能力,指导鱼道水力学设计,提高鱼道过鱼成功率,增殖鱼类资源总量,以四大家鱼之一的鲢(Hypophthalmichthys molitrix)为试验对象,研究其游泳能力及游泳行为。在(30±1)℃水温下,采用流速递增法,鲢的体长7.3~16.8 cm,体重6.10~66.50 g,按体长将鲢分为(8.17±0.59)cm、(10.09±0.53)cm、(11.84±0.67)cm、(13.94±0.68)cm、(15.90±0.64)cm共计5个试验组。结果表明,鲢的临界游泳速度为52~100 cm/s,相对临界游泳速度为5.90~7.14 BL/s,摆尾频率为98.7~432.2次/min。鲢的临界游泳速度随体长增加而增大,其线性拟合方程为Ucrit=4.908L+17.63(R2=0.998);其相对临界游泳速度随体长增加而减小,线性拟合方程为U'crit=-0.130L+8.025(R2=0.979);在整个试验过程中,根据鱼类对水流速度的游泳行为响应,鲢摆尾频率随水流速度的增大而增加,两者呈线性关系;在相同流速下,较长个体鲢的摆尾频率显著小于较小的个体。 相似文献
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西江肇庆段鱼苗群落结构组成及其周年变化研究 总被引：1，自引：0，他引：1
2006年1-12月对西江肇庆江段的鱼苗进行了周年采集,目前已鉴别的鱼苗达40种（属）,隶属于7个目14个科,其优势种类为主要优势种为鲴类（33.9%）、广东鲂（29.1%）、赤眼鳟（11.6%）、鲮（9.1%）、 条（6.1%）、鳊（2.9%）等,四大家鱼（青鱼、草鱼、鲢、鳙）的比例总共仅4.01%,鱼苗的季节分布上主要集中在4~9月,其它月份鱼苗种类及数量都很少。与历史资料相比,西江鱼苗群落结构已有显著性改变,其中四大家鱼资源已严重衰退,应该加强西江四大家鱼产卵场的监测与保护,并同时在增殖放流中增加其鱼苗比例。另外,本文也分析了西江中23种常见鱼苗的丰富度与水温、断面流量的相关关系,以期为以生态保护为目的的水文节律人为调节提供基础性数据。 相似文献
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浅议我国鱼道运行管理存在的问题及对策-以洣水洋塘鱼道为例 总被引：1，自引：0，他引：1
鱼道作为能够有效联通闸、坝上下游水流,为鱼类提供上溯、下行通道的有效途径,一直以来被作为水利水电工程建设鱼类保护的重要措施采用,但由于认识、经费、运行管理等多方面因素,其过鱼效果及发挥的作用难以被肯定。本文在综述国内外鱼道运行管理体制现状基础上,以洣水洋塘鱼道为例,分析总结了该鱼道兴衰历程,提出我国鱼道运行管理应提升对过鱼设施建设必要性的认知度、捋顺管理机制体制、建立生态补偿机制的对策与建议,力求能够为鱼道这项鱼类保护措施的建设与发展提供支持。 相似文献
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西江肇庆江段渔业资源现状及其变化 总被引：7，自引：0，他引：7
2006～2007年的4～6月对西江肇庆江段渔业资源进行调查.西江渔民主要以三层流刺网、抛网为主要作业网具.调查共采集鱼类75种,隶属23科、65属.与历史资料对照,目前西江肇庆江段鱼类的种类组成与结构已发生较大变化.捕捞种类主要为广东鲂、赤眼鳟、鲮、鯿、海南红鲌、花(鱼祭)、黄尾鲴、鲤、鲢、草鱼等.中华鲟、鲥鱼、三线舌鳎等已经在渔获物中消失、鳗鲡、花鳗鲡、卷口鱼、大眼红鲌等重要经济鱼类甚为少见.四大家鱼的资源量日趋衰竭,其中鳙的数量相对出现较多,而青鱼和草鱼产量极少.不同种类的渔获物在不同江段的分布具有明显差异性,广东鲂在产卵场江段有明显的集群现象.广东鲂、鲮、鳊和花(鱼祭)等捕获规格有所下降,可能是捕捞压力过大导致,而赤眼鳟、黄尾鲴的捕获规格有所增加,资源种群状况比历史上的好. 相似文献
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亚马逊流域玛代拉河Santo Antonio 鱼道设计与建设的启示 总被引：1，自引：0，他引：1
Santo Antonio过鱼设施位于亚马逊河最大支流玛代拉河下游,其设计规模宏大,在世界范围内鲜有,并且工程建设地所在区域水文环境和鱼类生物学特征等与我国长江较为类似,通过分析该过鱼设施,得出启示主要包括：（1）过鱼设施是为生物对象设计的水利工程,其设计和建设过程中必须由工程师和生物学家紧密合作;（2）吸引水流对过鱼设施的成败起关键性作用,虽然吸引水流系统需要加大投资并且运行过程中会损失大量的水能,但从确保过鱼设施效果而言是非常必要的;（3）物理模型对于鱼道进口位置,鱼道内部水力学特征的确定等具有重要参考价值,尤其在1:1局部模型内开展的生物学实验是细化和优化鱼道内部结构细节的有效方法;（4）卵石框(石笼）隔板的水池分隔方法兼具水池式鱼道与仿自然通道的双重特征,并且完工后还可以根据鱼道的运行情况灵活调整,非常方便;（5）进口处采用较高的人字闸门,即可适应尾水变化,又可与吸引水流系统相配合,创造出有效的吸引水流,一举多得;（6）全部采用大功率灯泡式水轮机是保护下行鱼类的有效措施;（7）监测系统和公众教育等配套设施的建设非常必要,有利于改进鱼道运行方式和提高过鱼效率。 相似文献
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为了解鱼类克服流速的能力，确定鱼道过鱼孔口流速，对鲤、鲫、鲢、草鱼、梭鱼、团头鲂、鲌、乌鳢、鲶等鱼进行试验。各种鱼类的感应流速多在0．2米／秒左右，适应流速是0.3米/秒，到0．8米，秒之间，极限流速的差别较大。以适应流速的上限值作为确定鱼道过鱼孔口的选定值是适宜的。试验结果还表明，鱼类克服流速能力，受其体型、体长、水温和所处环境条件等影响。从本试验结果及已建鱼道的观察资料分析，不同鱼类各体长组所能克服流速值的增长率是有差异的．选用时可按经验公式：V=(1．19—1．66)L1/2，进行推算。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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