锯缘青蟹幼体饵料蛋白质的营养价值评价

本文分析测定了锯缘青蟹幼体从刚孵化至大眼幼体各发育阶段及其饵料轮虫和卤虫无节幼体的氨基酸组成，并使用必需氨基酸指数(EAAI)来评价饵料蛋白质的质量.结果表明，青蟹各期幼体的氨基酸组成基本趋于一致，且与饵料转换不存在明显的相关性.对于各期幼体，饵料轮虫和卤虫无节幼体的必需氨基酸指数均大于90，可以认为，轮虫和卤虫无节幼体能够满足锯缘青蟹幼体对饵料中必需氨基酸的营养需求.     

黄、东海精致真刺水蚤种群遗传结构研究

采用等位酶技术分析了黄海中南部、东海陆架区3个站住的精致真剌水蚤(Euchaeta concinna)的苹果酸脱氢酶(MDH)、苹果酸酶(ME)和山梨醇脱氢酶(SDH)3个酶4个多态住点。生化遗传结构和遗传分化分析表明，3个站住样品的MDH基因型差异明显，不同站住间精致真刺水蚤平均遗传距离(D）为0．0768，平均遗传相似性（I)为0.9259。黄海南部(E3站住)和东海陆架区(E7站位)的精致真刺水蚤之间的D为0.0791；黄海中部(E2站位)与南部(E3站位)之间的D为0.067l。由此推论栖息于黄海和东海的精致真刺水蚤种群之间存在一定程度的遗传分化。     

海洋浮游甲壳类分子系统学研究进展

回顾海洋浮游甲壳类系统学研究的基础上，综述了生化水平和DNA(mtDNA和核DNA)水平的分子系统学研究现状。分子标记中DNA序列分析最为常用，其次是RFLP和RAPD分析，mtDNA主要应用于分类学、群体遗传学、种间分子进化和系统发育重建研究，而核DNA则应用于科以上较高阶元的系统发育和种内、近缘种间的遗传结构和遗传分化研究。最后对存在的问题和应用前景进行了展望。     

海洋浮游生物斑块分布的研究

斑块分布(patchy distribution)是海洋浮游生物空间分布的一个常见现象,遍及世界各海区。早在1893年,Haeckel已提出浮游生物分布的不均匀性。但对这个现象的深入观察和具体分析,则是从Hardy(1936)开始。他在一篇题为“海洋浮游生物不连续分布的观察”论文中指出,浮游生物的空间分布不是过去所想象的那样均匀,而是不均匀的、不连续的,常密集成块。之后,有关这方面的论著与日俱增,特别是Steele主编的《浮游生物群落     

锯缘青蟹视神经节免疫细胞化学研究

采用兔抗哺乳类血清,应用链霉菌抗生物素蛋白-过氧化物酶免疫细胞化学技术,观察了锯缘青蟹视神经节中5羟色胺、胰高血糖素、神经肽Y和生长抑素免疫阳性细胞和神经纤维的形态和分布,结果发现,视神经节的4个神经髓均有5羟色胺免疫阳性细胞,除X器检出1个较大型阳性细胞外,其余均为小型细胞.视外髓、视内髓和视端髓都具有胰高血糖素免疫阳性细胞,视端髓的神经髓质阳性染色深,X器中阳性细胞成群分布,窦腺免疫阳性反应强.神经肽Y免疫阳性细胞在视神经层和视外髓为小型阳性细胞,在视内髓和视端髓检出较大型阳性细胞,另有小型阳性细胞散布于X器中.生长抑素免疫阳性细胞分布于4个神经髓,数量少.4种免疫阳性物的特异性分布模式,可为其不同的神经生理作用提供形态学证据.     

The progress in the study of Arctic pack ice ecology

The sea ice community plays an important role in the Arctic marine ecosystem. Because of the predicted environmental changes in the Arctic environment and specifically related to sea ice, the Arctic pack ice biota has received more attention in recent years using modem ice-breaking research vessels. Studies show that the Arctic pack ice contains a diverse biota and besides ice algae, the bacterial and protozoan biomasses can be high. Surprisingly high primary production values were observed in the pack ice of the central Arctic Ocean. Occasionally biomass maximum were discovered in the interior of the ice floes, a habitat that had been ignored in most Arctic studies. Many scientific questions, which deserve special attention, remained unsolved due to logistic limitations and the sea ice characteristics. Little is know about the pack ice community in the central Arctic Ocean. Almost no data exists from the pack ice zone for the winter season. Concerning the abundance of bacteria and protozoa, more studies are needed to understand the microbial network within the ice and its role in material and energy flows. The response of the sea ice biota to global change will impact the entire Arctic marine ecosystem and a long-term monitoring program is needed. The techniques, that are applied to study the sea ice biota and the sea ice ecology, should be improved.     

Toxicity and Accumulation of Selenite in Four Microalgae

The toxicity and bioaccumulation of selenite in four microalgae, Spirulina platensis,Dunaliella salina, DunalieUa bardawill and Phaeodactylum tricornutum cultured in the presence of selenite were investigated. Lower concentrations of selenite were generally nontoxic and frequently stimulated algal growth, while higher concentrations of selenite inhibited algal growth. Selenite was more toxic to D. salina and D. bardawill than to S. platensis and P. tricornutum. All algae cultured in selenite were able to incorporate Se to different degrees, which depended on algal species. The distributions of selenite among intracellular macromolecular compounds were different among algal species : most of the selenite was associated with proteins in S. platensis, D. salina and D. bardawill, while most of the selenite was associated with lipids in P. tricornutum, which reflected the physiological differences among the algae. These observations suggest that algae are able to accumulate selenite and bind it with intracell~ar macromolecular compounds when exposed to high concentration of selenite. This may represent a form of storage or detoxification of selenite by the algae.     

Abundance, biomass and composition of spring ice algal and phytoplankton communities of the Laptev Sea （Arctic）

Abundance,biomass and composition of the ice algal and phytoplank-ton communities were investigated in the southeastern Laptev Sea in spring 1999.Diatoms dominated the algal communities and pennate diatoms dominated the dia-tom population.12 dominant algal species occurred within sea ice and underlyingwater column,including Fragilariopsis oceanica,F.cylindrus,Nitzschiafrigida,N.promare,Achnanthes taeniata,Nitzschia neofrigida,Naviculapelagica,N.vanhoef fenii,N.septentrionalis,Melosira arctica,Clindrothecaclosterium and Pyrarnimonas sp.The algal abundance of bottom 10 cm sea icevaried between 14.6 and 1562.2×10~4 ceils l~(-1)with an average of 639.0×10~4cells l~(-1),and the algal biomass ranged from 7.89 to 2093.5μg C l~(-1)with an av-erage of 886.9μg C l~(-1),which were generally one order of magnitude higherthan those of sub-bottom ice and two orders of magnitude higher than those ofunderlying surface water.The integrated algal abundance and biomass of lower-most 20 cm ice column were averagely 7.7 and 12.2 times as those of upper 20 mwater column,respectively,suggesting that the ice algae might play an importantrole in maintaining the coastal marine ecosystem before the thawing of sea ice.Icealgae influenced the phytoplankton community of the underlying water column.However,the“seeding”of ice algae for phytoplankton bloom was negligible be-cause of the iow phytoplankton biomass within the underlying water column.     

Identification and distribution of gonadotropin-releasing hormone-like peptides in the brain of horseshoe crab Tachypleus tridentatus

Gonadotropin-releasing hormone(GnRH) is a crucial peptide for the regulation of reproduction.Using immunological techniques,we investigated the presence of GnRH in horseshoe crab Tachypleus tridentatus.Octopus GnRH-like immunoreactivity,tunicate GnRH-like immunoreactivity,and lamprey GnRH-like immunoreactivity were detected in the neurons and fibers of the protocerebrum.However,no mammal GnRH-like immunoreactivity or lamprey GnRH-Ш-like immunoreactivity was observed.Our results suggest that a GnRH-like factor,an ancient peptide,existed in the brain of T.tridentatus and may be involved in the reproductive endocrine system.     

南极海冰区冰藻类群及兴衰过程

本文总结了国际上对南极冰藻类群及其生理生态特性的多年研究成果 ,结合我国科学家在南极长城站以及在戴维斯和中山站的越冬研究 ,阐述了南极海冰区的冰藻类群及其形成机理 ,对冰藻的形成、存活、旺发和消亡过程进行讨论 ,并对大洋浮冰区和近岸固定冰区冰藻类群的生态特性进行对比 ,提出了今后有待进一步深入研究的领域