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1.
世界洋底约有15%的面积被多金属结核覆盖,其中太平洋约23×106平方千米、印度洋约15×106平方千米、大西洋约8×106平方千米,总储量约3万亿吨。根据世界大洋底的地貌特征和构造位置以及多金属结核丰度、成分、地球化学特征,将世界大洋划分为15个多金属结核富集区,其中太平洋8个  相似文献   

2.
基于Argo资料的世界大洋温度跃层的分布特征   总被引:3,自引:0,他引:3  
基于2002年至2007年Argo浮标温度剖面资料,计算温度跃层特征参数,判定跃层的类型。在此基础之上,绘制了世界大洋四季温度跃层特征分布图。分析结果初步揭示了世界大洋温度跃层深度和强度的分布规律及其冬、夏两季的变化规律。  相似文献   

3.
历经30年的发展,世界邮轮业现已成为旅游业中增长最快的部门,并呈现诸多趋势特征。目前,亚太地区正在成为世界邮轮市场开发新的焦点,一些国际邮轮公司开始将中国作为市场开发的‘处女地’,国内主要沿海港城正紧锣密鼓地建设邮轮母港和停靠港,试图紧抓这一难得发展机遇。文章基于世界邮轮业发展趋势特征的分析,从产业定义、产业体系构建、产业布局和产业政策等综合角度探讨我国邮轮业发展的未来,为其科学发展提供理论参考。  相似文献   

4.
新编竖版世界地势图摒弃以往的传统模式,采用全数字化高程数据计算生成陆地和海底地形,生动地表达了世界地势的总体地貌格局。讨论了浅海域在世界地势图上的表达方式,介绍了世界浅海域在新编世界地图上的表达特征,统计了世界主要浅海域的基本信息,并给出了"世界浅海域一览表"。  相似文献   

5.
通过对我国沿海多次野外实地考查以及文献报道,采用统计学的分析方法,研究了马尾藻属海藻资源的物种构成和区系分布特征.结果表明,马尾藻属种数在我国海域的水平分布呈现出北少南多的趋势,黄、东海仅17种,南海达到124种、占世界马尾藻总数的36.47%.其中,黄海西区、东海西区、南海北区和南海南区种数及小区单一分布种类数分别为10、13、82和61种及2、3、52和42种.我国特有种类为64种、占世界尾藻总数的18.82%.在我国沿海马尾藻的垂直分布特征为:高潮带2种,低潮带91种,潮下带78种.  相似文献   

6.
本文以世界海域头足类的28个科及其重要种类的分布为依据,结合生境、生态和捕获状况,探讨了头足类的分布特点、分布趋向和区系特征。  相似文献   

7.
本文综述了中国台湾地区及世界部分主要海水养殖国家和地区的水产养殖病害情况,对鱼虾贝类的病毒性疾病、细菌性疾病及其他病症的流行情况、防治方法、病原特征、宿主范围和组织病理学特征等进行了较详细的介绍。本综述对我国的海水养殖业和水产病害研究将有重要的指导作用  相似文献   

8.
青岛是世界上有名的海港城市,也是我国海洋科学研究的基地。海洋科技力量在全国占绝对优势,青岛的海洋工作是整个城市建设和发展的重要组成部分,应在对外开放中开创新局面。本文就青岛对外开放中海洋工作的现状和前景作些探讨。一、青岛沿海特征和海洋工作的现状 1.青岛的环境特征和海洋的开发  相似文献   

9.
张蕾 《海洋信息》2005,(4):7-7,10
在知识经济时代,高速信息网络已成为现代社会的标志特征之一,因特网以其快速的信息传递速度和丰富的信息资源已成为世界上规模最大、用户最多、影响最广的互联网络,档案部门也受到因特网的冲击.从我国的实际情况和世界各国的发展来看,因特网成为开发利用档案信息的有效途径.本文对档案信息化和网络化的重要性进行了初步分析及探讨.  相似文献   

10.
为促进我国新兴游艇旅游业的快速发展,文章总结游艇旅游业的概念和特征,分析世界游艇旅游业的发展现状和趋势,基于此提出对我国的启示。研究结果表明:游艇旅游业是包含多种产业活动的全产业链,具有产业集聚、租赁船队垄断、利基市场、商业模式多样和时节性等特征;目前世界游艇旅游业的发展呈欧美地区占主导、游艇租赁业蓬勃发展、游艇港口经营本地化以及跨区域管理制度待改进等状况,且具有集群化、本地化、多元化和智能化的发展趋势;未来我国应推进游艇租赁合法化,建设多层次游艇基础设施,加强游艇政策创新力度,丰富游艇旅游产品和培养游艇旅游业人才。  相似文献   

11.
RNA干扰,是1种由双链RNA引发的转录后基因沉默现象.作为1种有力的反向遗传学研究工具,RNA干扰被广泛用于阻断各种基因的表达.建立在RNA干扰技术基础上的基因治疗,被认为是治疗病毒性疾病的有效手段.在水产科学领域,RNA干扰在对虾病毒病控制上的应用近几年受到广泛的关注.病毒性疾病已经在世界范围内给对虾养殖业造成了严重的经济损失,目前还没有有效的控制手段.利用RNA干扰技术控制对虾病毒的侵染,是一个很有前途的方法.本文综述RNA干扰技术在对虾病毒病防治中的最新进展,并对RNA干扰技术控制病毒侵染的可能性进行探讨.  相似文献   

12.
龚梦馨  李明源 《海洋科学》2022,46(11):160-166
高密度、集约化水产养殖业的发展导致疾病不断发生并呈现日趋严重之势,同时,由于细菌对传统抗生素产生耐药性而使抗生素的使用受到越来越多的限制,世界各国科学家都在致力于研究替代抗生素的新疗法。噬菌体因为可以特异性地杀死某些细菌,对动、植物以及环境都没有副作用,因此,在水产养殖病害防治中呈现良好的应用前景。本文从噬菌体的特异性、安全性、赋形方法以及对环境的影响等方面对国内外水产养殖中的噬菌体治疗研究现状和存在的主要问题进行了简要论述,为了解学科进展,促进噬菌体在治疗中的成功使用提供了理论依据。  相似文献   

13.
对虾细胞培养及对虾病毒体外培养研究进展   总被引:1,自引:0,他引:1  
随着对虾病毒病研究的不断深入迫切需要建立连续性的对虾细胞系来揭示对虾病毒致病机理等关键问题。文章介绍了用于细胞培养的对虾种类、组织。用于细胞培养的对虾种类包括中国明对虾Fenneropenaeuschinensis、斑节对虾Penaeusmonodon、日本囊对虾Marsupenaeusjaponicus、凡纳滨对虾Litopenaeusvannamei等。用于培养的对虾组织包括甲壳下表皮、心脏、肝胰腺、鳃、肠上皮、淋巴、血淋巴、卵巢、神经、肌肉、造血组织等。同时重点介绍了离散细胞的方法和培养的方式,温度、pH、渗透压的选择,目前对虾细胞培养所用的培养基及促生长添加物,以及如何控制污染。探讨了目前在对虾细胞培养及建系中存在的问题和可能的解决途径,为对虾与其它甲壳类动物细胞培养及细胞系的建立提供参考。此外还介绍了对虾病毒体外培养的研究现状并探讨了可能的解决方案。  相似文献   

14.
Viral hemorrhagic septicemia virus (VHSV) and marine birnavirus (MABV) are the causative pathogens for some of the most explosive epidemics of emerging viral diseases in many Asian countries, leading to huge economic losses in aquaculture. Rapid molecular detection for surveillance or diagnosis has been a critical component in reducing the prevalence of pathogen infection. The loop-mediated isothermal amplification (LAMP) of DNA is currently one of the most commonly used molecular diagnostic tools, as it is simple, quick, and easy to amplify target DNA under isothermal conditions. In the present study, a novel and highly specific LAMP assay for the sensitive and rapid detection of VHSV and MABV infection in fish was developed. Using a set of synthesized primers matching a specific region of the genome, the efficiency and specificity of the LAMP assay were optimized in terms of the reaction temperature and DNA polymerase concentration, as they are the main determinants of the sensitivity and specificity of the LAMP assay. In particular, we demonstrated that our assay could be applied to efficient detection of VHSV and MABV infection in the wild fish, Paralichthys olivaceus. Our results demonstrate the simplicity and convenience of this method for the detection of viral infection in aquatic organisms.  相似文献   

15.
养殖锯缘青蟹呼肠孤样病毒粒子的电镜观察   总被引:2,自引:0,他引:2  
经过对患病青蟹Scylla serrata的组织进行了超薄切片电镜观察,在病蟹的鳃上皮细胞、心肌细胞、胃和肠道上皮细胞中发现了大量的呼肠孤样病毒粒子。该病毒粒子的大小为60 nm左右,二十面体对称,无囊膜,在感染组织细胞浆中呈晶格状排列。根据病毒的形态特征和组织分布形态,初步认为该病毒为水生呼肠孤病毒,暂将其命名为青蟹呼肠孤病毒(Scylla serratareo-like virus,Ss-REO)。  相似文献   

16.
Viruses are hypothesized to maintain diversity in microbial assemblages by regulating the abundance of dominant competitors and thereby allowing less-dominant competitors to persist in assemblages; however, there have been few empirical data sets to support this idea. In this study, we examined the relationship between the ratio of viral abundance to bacterial abundance, viral production, and the relative richness and diversity of bacterial assemblage fingerprints, in samples taken from geographically widespread locations (North Pacific gyre, the Amazon River plume and adjacent North Atlantic gyre, Gulf of Mexico, Southern California Bight and Arafura—Coral Seas) which are oligo- to mesotrophic. Bacterial assemblage richness and diversity as measured by automated rRNA intergenic spacer (ARISA) fingerprinting were significantly and positively correlated with the ratio of virus abundance to bacteria abundance (VBR) and to the rate of virus production only in the oligotrophic North Pacific gyre. ARISA fingerprint richness/diversity were not significantly correlated to viral parameters when assessed across all samples in surface waters, suggesting there is not a singular global quantitative relationship between viral pressure and host diversity within well evolved host/virus systems in different geographic locations in plankton. In sediments off Southern California, viral parameters significantly and negatively correlated with ARISA diversity, suggesting strong viral interactions in this habitat. To examine covariation of viral parameters and the relative abundance and diversity of rarer bacterial taxa (i.e., less-dominant competitor), the richness and diversity of diazotroph communities was measured using terminal restriction fragment length polymorphism (TRFLP) of a portion (nifH) of the nitrogenase gene. The richness and diversity of diazotrophic communities were significantly and negatively correlated with viral parameters across all locations. Since diazotrophs include many opportunistic taxa (e.g. Vibrionaceae), and because these bacteria may be more susceptible to viral attack due to enhanced resource uptake abilities and potentially rapid localized growth, it is possible that this negative effect was due to enhanced viral lysis. Consequently, virus infection may have positive effects upon bacterioplankton diversity in the oligotrophic ocean, by regulating the abundance of dominant competitors, and allowing rarer taxa to coexist; however, some rarer taxa (such as diazotrophs) may be more susceptible to viral attack due to opportunistic lifestyles.  相似文献   

17.
A study on relation between heterotrophic bacteria and shrimp disease¥//INTRODUCTIONHeterotrophicbacteria,whichobtainnutrient...  相似文献   

18.
It is known that by the general ‘geostrategy’ for the oceans we mean the behaviour of countries of the world in defending their own vital economic interests as projected on different oceans. The means for protecting national interests can be economic, political, diplomatic or military. This paper dwells in particular on these last aspects, offering in the first part some useful reflections on the analysis of regional seas. The second part gives elements for the understanding of the complex Mediterranean situation where the East-West confrontation is accentuated by widespread economic, political, ideological and ethnic contrasts between coastal states. For these reasons this sea can be defined as one of the most unstable and belligerent regions in the world.  相似文献   

19.
Glyn Ford 《Marine Policy》1983,7(2):122-123
India continues to be a paradox. It is a country that at one and the same time has mass urban and rural poverty and deprivation, and is among the world leaders in some sectors of high technology. This is typified by India's proud membership of the small group of nations who possess the atomic bomb. Attitudes towards high technology are also evident in government support for marine technology.  相似文献   

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