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潮间带沙井水养殖杂交鲟试验 总被引:1,自引:0,他引:1
杂交鲟(达氏鳇Huso dauricus♀×史氏鲟Acipenser schrenckii♂)具有生长速度快、适应力强等优点,已成为我国重要的鲟类养殖对象。由于其父母本均具有一定的洄游习性,对盐度变化具有较高的忍耐力,适合在淡水和咸淡水中生活,这为拓展杂交鲟的养殖范围、丰富鲟鱼的养殖模式提供了契机。浙江省南麂岛潮间带沙井水丰富,盐度范围在5~12之间,适合于杂交鲟生长。为了充分利用当地的水资源及丰富养殖品种,笔者自2005年至2006年在南麂岛开展了杂交鲟潮间带沙井水养殖试验,现报告如下: 相似文献
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俄罗斯鲟苗种培育技术 总被引:3,自引:0,他引:3
俄罗斯鲟原产于前苏联,主要栖息在里海和亚连海——黑海水系内。属洄游性鱼类,涸游到伏尔加河产卵。1993年俄罗斯鲟引进我国大连,并养殖成功。俄罗斯鲟个体大,生长速度快,抗病力强,经人工驯化,成为工厂化、池塘、水库养殖优良品种。近几年,我国养殖俄罗斯鲟技术不断完善,特别是饲料的研究,取得了突破性的进展。仔、幼及成鱼系列配方的使用和鱼病防治技术的提高,加速了鲟鱼养殖规模化的进程。利用饲料培育俄罗斯鲟苗种,成活率可达60%-96%,投喂一个月体重可达3g,2个月可达209。笔者把俄罗斯鲟苗种培育技术措施… 相似文献
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史氏鲟、杂交鲟温流水小水体养殖对比试验 总被引:1,自引:0,他引:1
鲟鱼类是大型的重要经济鱼类,也是极珍贵的鱼种,目前全世界已发现鲟鱼25种,其中有8种鲟鱼分布在我国的长江、黑龙江等水系,人工养殖的品种主要有俄罗斯鲟、史氏鲟、杂交鲟、中华鲟、匙吻鲟等。史氏鲟在近3000千米的黑龙江干流均有栖息,多数为定居型种类,有部分为半洄游性鱼类,一般认为其生存温度为1~26℃,但黑龙江鱼类研究所和广东少数单位的养殖驯化表明,史氏鲟在0~33℃仍能存活,摄食水温范围4~31℃〖1〗。每年的5~6月份为史氏鲟的产卵季节,产卵水温为18~26℃。史氏鲟初次性成熟年龄:雌鲟为9~1… 相似文献
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关键种对生态系统结构和功能发挥了重要作用,其变化可以引起群落结构振荡和演替,导致生态系统功能紊乱乃至崩溃,因此,了解生态关键种的长期变化有助于解析整个生态系统演替过程。本研究基于莱州湾1959年、1982年、1993年、2003年和2015年春季(5月)底拖网渔业资源调查数据,构建了莱州湾春季鱼类群落食物网拓扑结构,分析了其关键种的长期变化。1959~2015年莱州湾鱼类食物网包含物种21~46个,摄食关系范围70~296个,食物网拓扑结构密度范围为0.155~0.300,种间关联度0.140~0.182,符合自然条件下群落种间摄食关系。1959~2015年莱州湾鱼类群落关键种如下:1959年为六丝矛尾虾虎鱼(Amblychaeturichthys hexanema)、花鲈(Lateolabrax japonicus)、蓝点马鲛(Scomberomorus niphonius)和黄(Lophius litulon),1982年为鳀(Engraulis japonicus)、黄和小黄鱼(Larimichthys polyactis),1993年为带鱼(Trichiurus lepturus)、鳀和蓝点马鲛,2003年为细纹狮子鱼(Liparis tanakae)、鳀和黄,2015年为细纹狮子鱼、大泷六线鱼(Hexagrammos otakii)和六丝矛尾虾虎鱼;关键种由经济价值较高的花鲈、小黄鱼和蓝点马鲛等演变为细纹狮子鱼、鳀和六丝矛尾虾虎鱼等经济价值较低的种类;同时,关键种的栖息环境也由中上层与底层生境(蓝点马鲛、花鲈、鳀等)演变为底层单一生境(细纹狮子鱼、大泷六线鱼和六丝矛尾虾虎鱼);关键种的这种更替导致食物网拓扑结构向简单化发展,在某种程度上也增加了鱼类群落结构脆弱性。 相似文献
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20 0 1年我们与河北水利厅合作 ,特聘请上海水产大学的专家对我们这里的三座水库进行资源调查 ,专家们认为小海子水库是天然的养蟹基地。这是一个浅碟型平原型水库 ,库底平坦 ,水草丰茂 ,枯水季节生长的水草可达水面 70 %左右 ,底部腐植淤泥层厚 15cm左右 ,水色呈绿褐色 ,透明度在5 0~ 80cm ,日照时间长 ,日照数波动在 12 2 7~2 74 8h ,年平均气温为 13 5℃ ,日平均气温变动在 - 4 7~ 2 8 2℃之间 ,库区最高气温 39 8℃ ,最低 - 13 8℃ ,月平均水温变化为 2 4~ 2 2 9℃之间 ,月平均最高水温在 7月和 8月 ,最低在 12月和 1月。由于水… 相似文献
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C.D. de Silva 《Aquaculture International》1997,5(4):339-349
An electrophoretic analysis of six populations of Oreochromis mossambicus (Peters) and four populations of O. niloticus (L.) from several rivers and a fish hatchery in Sri Lanka was conducted to determine the degree of mixing within and between stocks. Genetic characterization of the O. mossambicus stocks showed that some degree of mixing with O. niloticus occurred in all but two of the populations examined, while in the case of the O. niloticus, all the populations had some degree of mixing of O. mossambicus alleles. Genetic identity calculated using Nei's coefficient gave values ranging from 0.9484 to 0.9895 for O. niloticus populations and 1.0 to 0.9940 for O. mossambicus populations, while interspecies comparisons ranged from 0.7531 to 0.9002. The implications of these results for fisheries management and aquaculture are discussed. 相似文献
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M. W. APRAHAMIAN P. HICKLEY B. A. SHIELDS G. W. MAWLE 《Fisheries Management and Ecology》2010,17(2):93-105
Abstract Inland fisheries in England and Wales have high economic and social values. Managing participation to maximise fishery performance is key to maintaining this status. The capital value of fishing rights for migratory salmonid fisheries is €165 million. Coarse fisheries contribute €1030 million to the economy. The central tenet to increasing participation in recreational salmonid fisheries is that an increase in stock size will result in more anglers accessing the fishery. This was examined for salmon on the rivers Usk and Lune where exploitation restrictions increased the number of salmon available to anglers. On the River Lune, the number of salmon available post‐intervention increased by 66%. There was no significant increase in catch while the number of anglers decreased by 16.3%. On the River Usk, the closure of the net fishery potentially resulted in an additional ~1200 salmon being available. Following closure, there was no significant change in rod catch or in the number of anglers. Increased participation is dependent less upon stock manipulation for coarse fisheries and more upon facilitating the activity. In recent years, urban fishery development programmes have provided improved access to local fishing opportunity. Also, new anglers have been targeted through campaigns such as Get Hooked on Fishing and the Scout Angler Badge. 相似文献
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为研究斑海豹生长规律,达到科学饲养的目的,对大连圣亚旅游控股股份有限公司豢养斑海豹进行体检,获取动物性别、年龄、体质量和体长等信息;通过SPSS 13.0软件对动物的生长曲线、体长-体质量关系和雌雄间生长差异进行分析。试验共获得30头豢养斑海豹的体检数据,雌性11头,雄性19头。统计分析发现:logistic、Gompertz和von Bertalanffy三种模型回归的斑海豹最大体长、体质量依次为167、170、171 cm和153、175、191 kg ;体质量-体长关系为(r2=0.908);研究还发现体长-年龄、体质量-体长间的相关关系模型能够较准确的反映斑海豹的生长规律,而体质量年龄模型准确度较差。控制年龄的协方差分析未发现雌雄斑海豹生长规律间的差异(体长:P >0.05;体质量:P >0.05)。 相似文献
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To validate the involvement of meiobenthos in cellulose breakdown in wetlands, meiobenthos were collected from sediments of
Lake Furen and the Biwase River in Hokkaido Prefecture, the Kako River in Hyogo Prefecture, and the Chinai River in Shiga
Prefecture. Cellulase activities of the meiobenthos were measured by cellulose zymographic analysis using sodium dodecyl sulfate
polyacrylamide gel electrophoresis (SDS-PAGE) gels containing 0.5% carboxymethyl cellulose. The results showed that most of
the Turbellaria, Nematoda, Harpacticoida, and Oligochaeta species exhibited cellulase activity. The molecular sizes of the
cellulase-active bands of the sediments in Lake Furen, the Biwase River, and the Chinai River coincided with those of meiobenthos.
The findings suggest that meiobenthos might play a major function in cellulose breakdown in these wetlands. This paper is
the first to report cellulase activity in meiobenthos and that they are possibly involved in the breakdown of cellulose in
wetlands. 相似文献
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