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中国鲎胚胎发育过程主要生化成分分析 总被引:5,自引:1,他引:4
中国鲎 (Tachypleustridentatus)隶属于节肢动物门 ,素有活化石之称。从鲎的胚胎发育过程看 ,其幼虫与寒武纪以前即已发生的三叶虫极为相似。因此 ,它在研究节肢动物的系统发生上具有重要意义。 2 0世纪 40年代OKA就采用活体染色法观察了美洲鲎胚胎发育的变化[1] ,对鲎的胚胎发育有了一定的了解。之后 ,日本学者关口晃一[2 ] 和我国学者王渊源[3 ] 、蔡心一[4 ] 、吴翊钦[5] 、廖永岩[6] 和王军[7] 等对中国鲎胚胎发育做了进一步的观察。而有关中国鲎发育过程中各发育期胚胎生化成分的变化迄今尚未见有公开报道。本… 相似文献
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鲎(Tachypleus tridentatusLeach),属节肢动物门、有螯肢亚门、肢口纲、剑尾目。有4亿多年的历史,俗有“活化石”之称,目前世界上主要有4种:东方鲎,美洲鲎,马来鲎,圆尾鲎。东方鲎主要分布于日本海以西,中国长江口以南,中南半岛以东一带沿海。它的血液呈蓝色,经加工后目前市场价格为6万美元/加仑,具有较高的医学和科学研究价值。 相似文献
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鲎,英文别名马蹄蟹(Horseshoe crab),隶属节肢动物门、肢口纲、剑尾目、鲎科。目前全世界现存的鲎分为2亚科3属4种,美洲鲎亚科(Subfamily Limulinae)仅1属1种即美洲鲎(Limuluspoly phemus);鲎亚科(Subfamily Tachypleinae)分为蝎鲎属和鲎属,由3种亚洲鲎组成,分别为蝎鲎属的圆尾蝎鲎(Carcinoscorpius rotundicauda)和鲎属的中国鲎(Tachypleus tridentatus)与南方鲎(Tachypleus gigas)。2019年3月世界自然联盟(IUCN)正式宣布中国鲎在红色名录中的等级从原来的数据缺乏(DD)变更为濒危(EN)。 相似文献
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长江河口锋区桡足类优势种聚集特征的研究↑(*) 总被引:4,自引:0,他引:4
对长江河口锋区桡足类优势种的聚集强度测度进行了分析。本文选择优势度Y≥0.1的桡足类为本水域优势种,丰水期优势种有:中华哲水蚤(Calanus sinicus)、真刺唇角水蚤(Labidocera euchaeta)、背针胸刺水蚤(Centropages dorsispinatus)、太平洋纺锤水蚤(Acartia pacifica)、火腿许水蚤(Schmackeria poplesia);枯水期有:中华哲水蚤、真刺唇角水蚤、虫肢歪水蚤(Tortanus vermiculus)、汤匙华哲水蚤(Sinocalanustenellus)、亚强真哲水蚤(Eucalanus subcrassus)。运用聚集强度指标,通过对这些优势种在长江口锋区空间分布特征的研究,发现长江河口锋区桡足类聚集强度丰水期高于枯水期;河口半咸 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