丹江口水库马口鱼肠道寄生蠕虫群落结构

从2004年8月到2005年11月在丹江口水库调查的847尾马口鱼(Opsariichthys bidens)肠道内共检得寄生蠕虫14种,其中线虫7种,复殖吸虫4种,棘头虫2种,绦虫1种。该寄生蠕虫群落以广谱性寄生虫为主。杜父鱼驼形线虫(Camallanus cotti)、头槽绦虫(Bothriocephalus acheilognathi)、卡斯杆咽线虫(Rhabdochona cascadilla)和木村小棘吻虫(Micracanthorhynchina motomurai)为群落的核心种。研究结果

野生与豢养长江江豚血清氨基酸含量比较

应用高效液相色谱(HPLC)技术,首次测定了湖北石首长江天鹅州白豚自然保护区野生长江江豚(Neopho-caena phocaenoides asiaeorientalis)和中国科学院水生生物研究所白豚馆人工饲养的长江江豚血清中17种氨基酸的含量。结果表明,除了脯氨酸Pro、蛋氨酸Met和组氨酸His外,人工饲养江豚血清中其余14种氨基酸(天门冬氨酸Asp、谷氨酸Glu、丝氨酸Ser、精氨酸Arg、甘氨酸Gly、苏氨酸Thr、丙氨酸Ala、异亮氨酸Ile、亮氨酸Leu、苯丙氨酸Phe、缬氨酸Val、赖氨

集胞藻PCC6803铜离子诱导表达平台的构建

在集胞藻PCC6803中,基因敲除是研究基因功能的最直接有效的方法,但是对于某些生存必需的基因则无法通过这种方法获得突变株。为研究集胞藻PCC6803中此类基因的功能,在其基因组中构建了一个petE基因启动子(PpetE)控制的铜离子诱导表达的平台。将集胞藻PpetE装配在lacZ报告基因的上游,通过同源双交换整合到这种蓝藻的基因组中。通过调节培养基中铜离子的浓度发现,lacZ的表达能够人为控制。特别是当铜离子浓度在6—400nmol/L范围时,LacZ活力随铜离子浓度增加呈S型增长关系。利用这个铜离子诱

鲤鱼(Cyprinus carpio L．)GH受体的分子克隆及其两种转录子的发现

应用反转录-PCR及RACE技术,从二龄鲤鱼肝组织中克隆了生长激素受体(GHR)的全长基因,其开放阅读框编码602个氨基酸,其中包括244个氨基酸的胞外激素结合结构域,24个氨基酸的跨膜区域和334个氨基酸的胞内信号传导区域．序列分析表明：无论在基因水平还是蛋白质水平,鲤鱼GHR与鲫鱼GHR均具有较高的同源性．用一对基因特异性引物在研究二龄鲤鱼GHR的组织分布时发现：肝与其他组织的扩增产物大小不一致(肝组织中的约小100 bp),测序结果以及基因组PCR表明这是由于一个97 bp的内含子选择性剪切造成的．

江苏奥杜藻属一新变种

本文记述了产自华东地区江苏徐州的一个新变种徐州奥杜藻AudouinellachalybeaBoryvar.xuzhouensisHuaetXie .它与原变种的主要区别在于其植物体高达 1 0～ 2 0mm ;叶绿体不规则片状 ,周生 ;单孢子囊常产生于繁殖枝的内侧。

湖北土荆芥挥发油化学成分研究

用色谱－质谱联用技术对湖北产土荆芥挥发油的化学成分进行了分析。鉴定了８０种组分。其中主要组分是：薄荷醇（３１．３３１％）、α－松油烯（１３．２１０％）、香芹艹孟烯醇（８．５２６％）、对伞花烃（８．３４３％）、１，８－桉叶油素（７．４１７％）等５种化合物。被鉴定的８０种成分，共占挥发油总含量的９９．１１２％。

水库鱼体汞积累的预测

回归分析表明，在所研究的长江流域的12个水库中，水库与河流鲤鱼汞含量的比值F与水库集水面积A和径流量Q的比值呈显著的负相关：F＝2．5096－0．48047A／Q（r＝0．795，n＝12）凤滩水库调查结果证实了此回归方程的可靠性。实测的F值与预测值比较，相对误差为23．1％。用此模型预测三峡大坝建成蓄水后将加剧鱼体对汞的生物富集作用，局部水域存在鱼体汞含量超过我国食品汞含量标准的可能性。本文讨论了河流与水库中鱼体对砷、汞、硒、铅和镉元素积累的特点。比较其富集系数指出，在同一水系中，河流的鲤鱼对砷和硒的富

似鮈类鱼类的系统发育研究（鲤形目：鲤科）

本文通过对似类８属１３种和外类群７属１０种鱼类的比较研究，选取３７个骨骼及外部特征，运用外类群比较法进行特征分析，根据分支系统学原理重建了似类的系统发育。特征分析和系统发育分析表明似类是具有许多共同离征的单系群，朝着流水性底栖生活和刮食性的主干方向发展；其中以似属最原始，胡属最特化构成７对姐妹群。蛇属是较早分化出的相对特化的类群，棒花鱼属和小鳔属的关系相对较远。

武汉东湖磷含量的变动及其分布

本文总结了武汉东湖水体中磷含量(均以PO_4计算)的周年逐月季节和年际变动及其分布上的差异(1973—1985年)。按面积加权法计算总磷的平均含量为0.244毫克/升(1983—1985年),总溶解磷和溶解活性磷的平均含量分别为0.121毫克/升和0.051毫克/升(1981—1984年)。总磷和总溶解磷周年中出现两次高峰含量,即春季(3—5月)和夏末秋初(8—9月)。低含量出现在水温最低的冬季(12—2月)。周年中溶解活性磷高峰含量出现在冬末春初(1—3月),低含量多数出现在春末夏初(5—7月)。东湖水

杭州西湖水生植被恢复的途径与水质净化问题

<正> 我国著名的风景湖泊——杭州西湖、南京玄武湖、北京昆明湖、武汉东湖和昆明滇池等,由于人类经济活动的影响,特别是由于生活污水的大量排人和渔业生产的影响,致使湖泊富营养化问题越来越严重,不仅降低了旅游价值,而且有害于沿湖居民的生活和健康,因此引起人们的极大关注。杭州西湖富营养化程度相当严重,尽管在五十年代采取了挖泥疏浚的措施,

Aerobic biodegradation of hexachlorobenzene by an acclimated microbial community

The aerobic degradation of hexachlorobenzene (HCB) by an acclimated microbial community which isolated from a contaminated site and acclimated in our laboratory was investigated. The enriched microbial community was capable of biodegrading HCB when cultivated in minimal salts medium and supplied HCB as the sole carbon source. The efficiencies of microbial community in the degradation of HCB under different pH and temperatures were examined. The phylogenetic analysis for the nearly complete sequences of 16S rDNA demonstrated that the bacteria assemblage in the microbial community was dominated by Azospirillum and Alcaligenes groups.

Oligochaete assemblages associated with macrophytes in the Liangzi Lake District, China

The assemblage of oligochaetes in the Liangzi Lake District, located in middle reaches of the Changjiang River, was studied from May to August, 2001. To establish species composition, richness, and abundance and detect the influence of environmental variables on oligochaete distributional patterns, 45 localities were sampled. All total, 20 species belonging to the families Naididae (eight species), Tubificidae (11 species), and Lumbriculidae (one species) were found. Branchiura sowerbyi, Tubifex sp. 1, and Aulodrilus pluriseta were the dominant species and contributed nearly 70% of the total abundance. The 45 sampling sites were separated into three groups based on composition and relative abundance of benthic oligochaete communities using two-way indictor species analysis associated with detrended correspondence analysis. Canonical correspondence analysis indicated that two plant variables (total plant cover and total submersed macrophyte biomass) were strongly correlated with the faunal gradient (p < 0.05). Other predicator variables were water depth and total nitrogen.

Investigations into the perplexing interrelationship of the Genus Takifugu Abe, 1949 (Tetraodontiformes, Tetraodontidae)

The phylogenetic relationships within the genus Takifugu Abe, 1949 (Tetraodontiformes, Tetraodontidae) remain unresolved. Because of the use of Takifugu as model organisms, the resolution of these relationships is crucial for the interpretation of evolutionary trends in biology. Pufferfishes of this genus are comprised of a comparatively small number of species and are mainly distributed along the coastal region of the western part of the Sea of Japan and the coastline of China. Mitochondrial gene sequences were employed to test the phylogenetic hypotheses within the genus. Seventeen species of the genus were examined. Molecular phylogenetic trees were constructed using the maximum parsimony, neighbor-joining, maximum likelihood and Bayesian methods. Our hypothesis of internal relationships within the genus differs from previous hypotheses. Our results indicate that (1) the genus Takifugu is a monophyletic assemblage; (2) the genus is divided into 6 subgroups based on the molecular data; and (3) there is low genetic diversity among the species within this genus. In addition, speciation within Takifugu appears to be driven by hybridization and isolation by distribution. Our results also suggested that the taxonomy in the genus should be clarified based on both molecular and morphological data.

Floral survey of the diatom genera Cymbella and Gomphonema (Cymbellales, Bacillariophyta) from the Jolmolungma mountain region of China

We report on taxa from the diatom genera Gomphonema and Cymbella (Cymbellales, Bacillariophyta) found in the Jolmolungma Mountain region of China. This region is unique for its diversity of habitats, which include rivers, springs, moist soil, snowfields, swamps and lakes. We re-examine diatom taxa found in samples first documented in 1973 (Jao et A, 1973) and incorporate recent taxonomic revisions from the literature. In the genera Gomphonema and Cymbella we report 113 species and varieties. Of these 113 taxa, 59 are new record for China; 1 new combination, Encyonema jolmolungmensis, is made. Morphometric data and habitat features are reported for each taxon. Their distribution is strongly correlated to their microhabitats.