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141.
为了研究上海国际航运中心洋山深水港区四期工程导流堤工程对周边海域流场的影响,采用MIKE21里面的HD模块构建杭州湾及长江口海域整体潮流数值模型,分别对导流堤建成前后附近海域流场进行数值模拟,分析导流堤建成后工程附近海域流场特征。研究表明:导流堤建成后,四期码头前沿较大范围的回流区和缓流区基本消失,导流堤和四期码头前沿海流流向基本与码头走向保持一致,流速有所增大,导流堤的建设使码头前沿海流得到很好的改善,起到了归顺潮流的作用,有利于码头前沿水深的维持及船舶靠离港的安全。  相似文献   
142.
正由中国高科技产业化研究会海洋分会和中国海洋学会科技开发与产业化工作委员会共同策划的"2014中国(天津)国际海洋水文气象监测技术及仪器设备展示交易会"将于2014年5月23—25日在天津滨海新区会展中心举办。交易会将为我国海洋科技领域提供更为有利、有效和便捷的技术服务。凡从事海洋水文气象仪器生产商、贸易商、代理商、服务商及相关海洋技术专业的企事业、机关职能管理等单位均可参与技术交流和合作。会议展示内容涉及4个方面:1)海洋水文气象监测系统及仪器设备、水文气象海洋传感器技术、数据采集技术、数据传输技术、系统软件应用技术、水质自动监测、野  相似文献   
143.
<正>《海洋工程》于1983年创刊,是由中国科学技术协会主管,中国海洋学会主办,南京水利科学研究院、上海交通大学承办的综合性学术刊物。已被美国剑桥科学文摘(CSA)、联合国《水科学和渔业文摘》(ASFA)、日本科学技术振兴机构中国文献数据库(JST)、中国科技核心期刊(中信所)、中国科技期刊精品数据库(中国知识资源总库)、中国核心期刊(遴选)数据库(万  相似文献   
144.
正《海洋科学进展》是由中国海洋学会和国家海洋局第一海洋研究所共同主办,国内外公开发行的全国性海洋科学学术期刊。主要刊登国内、外在海洋科学基础、应用基础和应用研究以及与海洋有关的交叉学科领域最新的学术成果。主要栏目:院士论坛、学术论文、研究报道、学术讨论、专题评述与综述、实验室介绍、海  相似文献   
145.
To determine the optimal salinity for growth and first sexual maturity of ExopaIaemon carinicauda, the effects of salinity on growth and reproductive performance of early juvenile prawns of E. carinicauda were evaluated under laboratory conditions. Postlarvae from the same female broodstock were reared at six salinity levels (5, 10, 15, 20, 25, and 30) for 12 weeks. The specific growth rate (SGR) and survival rate (SR) under different salinity levels in the first 6 weeks were calculated and compared. SGR was significantly influenced by salinity. Prawns reared in salinity of 10 grew significantly faster (P〈0.05) than those reared in salinities of 5, 20, 25, and 30. However, ANOVA confirmed that there was no significant effect among the six salinity levels on SR. For the next 6 weeks, the body length (BL), body weight (BW) at the first sexual maturity, and the age at median sexual maturity (As0) of females were measured and compared. Female prawns reared at salinity of 10 presented significantly shorter A50, but no significant differences among the six salinity levels for BL and BW at the first sexual maturity were observed. Based on the above information, the optimal salinity for growth and first sexual maturity of juvenile E. carinicauda is approximately 10.  相似文献   
146.
The northern Indian Ocean (NIO) experienced a decadal-scale persistent warming from 1950 to 2000, which has influenced both regional and global climate. Because the NIO is a region susceptible to aerosols emis- sion changes, and there are still large uncertainties in the representation of the aerosol indirect effect (ALE) in CMIP5 (Coupled Model Intercomparison Project Phase 5) models, it is necessary to investigate the role of the AIE in the NIO warming simulated by these models. In this study, the authors select seven CMIP5 models with both the aerosol direct and indirect effects to investigate their performance in simulating the basin-wide decadal-scale NIO warming. The results show that the decreasing trend of the downwelling shortwave flux (FSDS) at the surface has the major damping effect on the SST increasing trend, which counteracts the warming effect of greenhouse gases (GHGs). The FSDS decreasing trend is mostly contrib- uted by the decreasing trend of cloudy-sky surface downwelling shortwave flux (FSDSCL), a metric used to measure the strength of the AIE, and partly by the clear-sky surface downwelling shortwave flux (FSDSC). Models with a relatively weaker AIE can simulate well the SST increasing trend, as compared to observation. In contrast, models with a relatively stronger AIE produce a much smaller magnitude of the increasing trend, indicat- ing that the strength of the AIE in these models may be overestimated in the NIO.  相似文献   
147.
无震脊或海山链俯冲对超俯冲带处的地质效应   总被引:3,自引:1,他引:2  
鄢全树  石学法 《海洋学报》2014,36(5):107-123
全球海底分布着众多的无震脊或海山链,且在太平洋、印度洋及大西洋均存在靠近俯冲带的海岭。除小安德列斯弧外的巴拉克达脊和蒂勃朗脊起源自转换断层外,一般认为它们由与板块构造动力学迥异的地幔柱动力学所形成的。在板块汇聚边缘处,与扩张脊处所形成的正常洋壳一起,无震脊或海山链俯冲于陆缘弧或洋内弧之下,其对弧及弧后地区的地质效应(构造、地貌、地震以及岩浆作用等)有别于正常洋壳俯冲。无震脊或海山链的俯冲通常造成俯冲带地区的上驮板块的局部异常抬升、俯冲剥蚀作用效应的加强、海沟的向陆迁移以及地震强度的增加。同时,无震脊或海山链俯冲时,其携带的具富集地球化学特征的物质不仅影响着地幔地球化学,也对弧及弧后火山熔岩化学产生明显影响,并对超俯冲地区的热液矿床的形成产生重要影响。最后,本文指出了我国有关无震脊或海山链俯冲的可能的研究方向包括黄岩海山链俯冲对吕宋岛弧的可能影响、印度洋无震脊俯冲对青藏高原局部地区的影响,有我国学者参与的IODP344航次的研究对象——科科斯脊俯冲对哥斯达黎加地震成因的效应以及位于西太平洋地区靠近俯冲带的一些无震脊等。  相似文献   
148.
<正>"第七届海洋强国战略论坛"定于2014年10月31日在江苏省南京市召开。本次论坛旨在紧紧围绕党的十八大作出的建设海洋强国的重大部署和习总书记关于建设海洋强国的指示精神,以"依海富国、以海强国、人海和谐"为主题,充分交流近一时期为落实海洋强国战略,推动经济社会发展,我国科学家在海洋自然科学及社会人文科学领域所取得的新观点、新成果、新  相似文献   
149.
A sediment sample was collected from a deep-sea hydrothermal vent field located at a depth of 2 951 m on the Southwest Indian Ridge. Phylogenetic analyses were performed on the prokaryotic community using polymerase chain reaction(PCR) amplification of the 16 S rRNA and nifH genes. Within the Archaea, the dominant clones were from marine benthic group E(MBGE) and marine group I(MGI) belonging to the phyla Euryarchaeota and Thaumarchaeota, respectively. More than half of the bacterial clones belonged to the Proteobacteria, and most fell within the Gammaproteobacteria. No epsilonproteobacterial sequence was observed. Additional phyla were detected including the Actinobacteria, Bacteroidetes, Planctomycetes, Acidobacteria, Nitrospirae, Chloroflexi, Chlorobi, Chlamydiae, Verrucomicrobia, and candidate divisions OD1, OP11, WS3 and TM6, confirming their existence in hydrothermal vent environments. The detection of nifH gene suggests that biological nitrogen fixation may occur in the hydrothermal vent field of the Southwest Indian Ridge. Phylogenetic analysis indicated that only Clusters I and III NifH were present. This is consistent with the phylogenetic analysis of the microbial 16 S rRNA genes, indicating that Bacteria play the main role in nitrogen fixation in this hydrothermal vent environment.  相似文献   
150.
南大西洋沉积物中多环芳香化合物的组成特征研究   总被引:1,自引:0,他引:1  
10 samples of sediments obtained from the South Mid-Atlantic Ridge were measured for the abundances and distributions of polycyclic aromatic compounds(PAHs). The total concentrations of PAHs(∑PAHs) ranged from 2.768 to 9.826 μg/g dry sediment. The ∑PAHs was higher in sample 22V-TVG10 and sample 26V-TVG05 which were close to hydrothermal fields, with the lowest value in sample 22V-TVG14 which was farthest from hydrothermal fields, suggesting a probable hydrothermal origin of ∑PAHs of samples. Approximately nine kinds of PAHs were identified, and low molecular mass tricyclic and tetracyclic aromatic compounds were predominant in the samples. The concentrations of fluoranthene which were typical as hydrothermal alteration compounds were the highest among PAHs with dry weight between 0.913–3.157 μg/g. The phenanthrene homologue was most abundant in the samples, and the ratios between parent phenanthrene and methylphenanthrene which probably reflected the degree of hydrothermal alteration ranged from 0.097 to 1.602. The sample 22V-TVG10 possessing a maximum ratio value showed the intense influence of the hydrothermal alteration on this sample, which might further imply that PAHs in sediments were mainly derived from the hydrothermal alteration.  相似文献   
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