聚类分析法在浅海水团分析中的应用及黄、东海变性水团的分析

本文引入变性水团概念,用聚类分析确定黄、东海浅海海域变性水团的边界及其变化。根据给定的标准进行聚类,确定了水团的个数、边界及混合区。 由聚类方法所得结果看出,在该海区中有八个变性水团。根据温、盐相对指标,将这些水团分为九种不同的特征。也可以把这些水团划分为三种盐度类型。在温—盐点聚图上,不同变性水团的温盐点,分布于一条曲线附近,它体现出逐级变性的特点。各变性水团的变化范围都很大,这说明该海区中水团变性强烈。在暖季中的增温降盐和冷季中的降温增盐,可认为是整个黄海和东海水体变性的特征。所有季节性水团都经历一个形成与消亡的过程。 文中讨论了变性水团和海洋环境的相互关系。水团变性是热力因素和动力因素共同作用而产生的。通过变性水团的分析,作者认为,在该海区水团的变性中,热力因素起着主要作用。变性水团界线的舌状分布与流向之间的关系是很明显的,可作为分析环流的旁证。最后描述了变性水团和底层中心渔场之间的关系。     

A reliable and sensitive closing gear

The model QQC_(2-2) plankton net closing gear is a device designed to control the stratifiedsampling of the plankton net by means of a messenger. The device in its fie1d use has met with98% success in 766 times of strtified sampling of plankton at 157 stations during separatesurveys of Fujian coast zone, the Taiwan Strait, and the central section of the South China Sea,     

利用牙鲆鳃细胞系分离和培养淋巴囊肿病毒

本文利用牙鲆鳃细胞系进行了养殖牙鲆淋巴囊肿病毒的分离及培养 ,并通过电镜对培养细胞中淋巴囊肿病毒的形态及感染循环进行了初步研究。将病鱼的淋巴囊肿组织无菌滤液接种牙鲆细胞系 ,细胞出现了明显的细胞病变 ( Cytopathic effect,CPE)。电镜观察在培养细胞的胞质中有病毒的包涵体 ,胞质中散在 6角形、5角形或圆形的病毒粒子 ,大小为 10 0～ 140 nm之间。在感染细胞的线粒体中也存在大量的病毒颗粒。     

利用RAPD和AFLP标记初步构建太平洋牡蛎的遗传连锁图谱

利用RAPD和AFLP标记 ,以一回交家系 [(Miyagi×Hiroshima)×Miyagi]为作图群体 ,构建了太平洋牡蛎的遗传连锁图谱。用经过筛选的 3 3个RAPD引物和 1 1个AFLP引物组合 ,对父母本和 80个子代个体进行了遗传分析。共得到母本分离标记 1 93个 ,其中 1 44个符合1∶1孟德尔分离规律。父本分离标记 1 5 6个 ,其中 1 1 1个符合 1∶1孟德尔分离规律。雌性框架图包括 99个遗传标记 ,定位在 1 2个连锁群中 ,覆盖 985 2cM ,标记间平均间隔 1 1 3cM。另外有 3个三联体 ,7个连锁对 ,图谱共覆盖 1 1 6 5 7cM。雄性框架图包括 72个遗传标记 ,分布在 8个连锁群 ,覆盖 81 1cM ,标记间平均间隔 1 2 7cM。另外有 4个三联体 ,3个连锁对 ,图谱共覆盖93 1 8cM。     

Diagnosis of iridovirus in large yellow croaker by PCR

A rapid and sensitive PCR-based method for the detection of the large yellow croaker iridovirus(LYCIV) is described,which involves the amplification of a 295 bp fragment of the LYCIV ATPase gene from DNA isolated from naturally infected fish spleen.Sequencing of LYCIV ATPase gene fragment showed it shared 100% nucleotide sequence homology with the corresponding region of the ATPase gene of red sea bream iridovirus(RSIV) and sea bass iridovirus(SBIV),suggesting that LYCIV was homologous with RSIV and SBIV at least in part of the gemone.The specificity and sensitivity of the PCR procedure were tested on the iridovirus-infected fishes,the expected fragment was detected from spleen DNA samples of infected fishes,whereas no fragments were amplified from healthy fish spleen DNA,white spot syndrome baculoviruses(WSBV) DNA and pseudorabies virus(PRV) DNA.Detection limit of this method was 10^-7 ng positive plasmid DNA containing target sequence,equal to about 100 virions.In the infected experiment,first positive detection(1/4) appeared at Day 3 post-infection,all fish(4/4) tested positive at Day 7,however obvious symptoms were observed at Day 8,so LYCIV infection could be detected prior to the appearance of obvious symptoms.These results indicate that this PCR method could be used for early,rapid and specific detection of LYCIV infection.     

雌雄比对海带雌配子体发育的影响

本实验进行了不同雌雄比对海带雌配子体发育的影响。结果表明：雌雄比(鲜重)为1：1及2：1，实验组出现排卵时间最早，且发育率高，实验第20天，发育率超过70％，孢子体正常。5：1，10：1，20：1实验组随着雄性比例的减少，发育率逐渐降低，随着培养天数的增加，三个实验组均出现未受精卵及畸形孢子体，雌雄比越大，未受精卵数目越多。     

In-Situ Observation of Fluid Mud in the North Passage of Yangtze Estuary, China

Observations of fluid mud were made in the lower North Passage of the Yangtze Estuary in February 2000, on 10 -11 August 2000, on 30 - 31 August 2000 (after two strong typhoons), on 21 - 24 August 2000 (neap tide) and on 3 -6 September 2000 (mean tide) respectively. In situ data show that the fluid mud in this area consists of fine cohesive sediment (median size 7.23 μm). The formation and movement of fluid mud varied during the neap-spring and flood-ebb tidal cycle. Observations suggest that fluid mud phenomena in this area may be categorised in a three-fold manner as slack water, storm and saltwedge features. The thickness of the fluid mud layer of slack water during the neap tide ranged from 0.2 to 0.96 m, whereas during the mean tide, the thickness ranged from 0.17 to 0.73 m, and the thickness of the fluid mud layer was larger during slack water than at the flood peak. Shoals cover an area of 800 km^2 with a water depth smaller than 5 m. Erosion of these extensive intertidal mudflats due to storm action provides an abundant sediment source. This is particularly significant in this estuary when the tidal level is lower than 5 m. The lower North Passage is a typical zone of saltwater wedging, so the saltwedge fluid mud has the most extensive spatial range in the estuary.     

Sediment transport pattern at the Barra Nova inlet, south Portugal: a conceptual model

The Barra Nova inlet, in south Portugal, is known to migrate progressively southeastwards under wave action. The morphodynamics of this system during a representative year suggests that this long-term evolution is dependent on a seasonal behavior of the tidal inlet which can be described through a three-stage model of post-storm, transition and extended fair-weather conditions. Processes involved in this evolution indicate that the historical migration of the Barra Nova is not dependent on the longshore drift forcing constricting the channel on the updrift coast, but rather on the adjustment of the system to a major erosion of the downdrift coast during short storm events.     

耳鲍(Haliotis asinina)核糖体小亚基(18S rRNA)编码基因的克隆与序列分析

采用分子生物学的方法,对南海不同海区的两个地理群体耳鲍(Haliotis asinina)18S rRNA基因全长进行了克隆和序列分析,并将耳鲍18S rRNA基因的序列与NCBI数据库中已收录鲍的18SrRNA基因进行了比较。结果发现,南海耳鲍核糖体18S rRNA基因与耳鲍H.asinina isolate H11核糖体18S rRNA基因序列的相同率高达98%;同一地理群体内耳鲍核糖体18S rRNA基因序列完全一致;不同地理群体间耳鲍核糖体18S rRNA基因在碱基组成上的相似率为99%,仅在某些位点处发生了碱基替换,即腺嘌呤(T)被鸟嘌呤(G)替换;同时,将这两个不同群体中耳鲍的18S rRNA基因与泰国耳鲍18S rRNA基因序列进行比较分析发现,它们之间也只是发生了碱基替换。