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1.
尹希刚  吕阳  沙忠利 《海洋科学》2020,44(8):239-251
利用文献处理工具Bibexcel和网络分析工具Pajek对SCIE和SSCI文献数据库1990—2020年全球海洋生态环境保护文献数据进行统计与可视化分析,以期揭示该领域的科研产出情况、领域知识基础、研究热点分布及前瞻发展态势。研究结果表明:海洋生态环境保护领域文献产出近30年来持续增长;美国、澳大利亚、加拿大、法国等国家在该领域内有着较强的科研竞争力和学术影响力,其中美国处于研究合作核心地位,美国加利福尼亚大学、法国国家科研中心等机构为主要发文机构;海洋生态环境保护研究的热点方向主要为海洋生态环境修复与管控、气候变化、生态系统服务、海洋保护区等;该领域研究学科交融趋势明显,研究者应充分借鉴、吸收其他学科理念和方法,加强海洋生态环境与气候变化、人为活动及生态物种等因素的制衡与协同。  相似文献   

2.
以Web of Science信息平台的SCIE数据库为数据源,利用文献计量方法,分析国际冷泉系统研究的年度变化、期刊分布、主要研究国家、机构的影响力及合作情况以及国际研究热点领域。研究结果发现:国际冷泉系统研究论文产量一直呈增长趋势;美国论文产出数量最多、合作中心性最强。德国亥姆霍兹国家研究中心联合会发文最多。中国近三年发文比例和第一国家发文比例均排名第一,其中发文最多的机构为中国科学院。微生物甲烷厌氧氧化、冷泉区生物多样性以及冷泉碳酸盐岩的矿物学和地球化学是研究热点。  相似文献   

3.
统计了1982-2014年国家海洋局被美国Web of Science核心合集数据库收录的4 466篇SCI科技论文,通过分析SCI论文产出数量和被引次数,了解国家海洋局与全球科研机构合作情况、热点学科分布和国际学术影响力状况。结果显示:国家海洋局的科研合作伙伴遍布全球大约60个国家和地区,1 560所大学和研究机构;在基础研究领域和应用研究领域都取得了许多国内外较高水平的成果;其优势学科向国际前沿延伸的态势较为明显,影响和辐射作用越来越大。这说明以国家海洋局为代表的我国海洋科学学术国际影响力呈现增长的态势。  相似文献   

4.
统计了1982-2014年国家海洋局被美国Web of Science核心合集数据库收录的4466 篇SCI科技论文, 通过分析SCI论文产出数量和被引次数, 了解国家海洋局与全球科研机构合作情况、热点学科分布和国际学术影响力状况。结果显示:国家海洋局的科研合作伙伴遍布全球大约60个国家和地区, 1560所大学和研究机构;在基础研究领域和应用研究领域都取得了许多国内外较高水平的成果;其优势学科向国际前沿延伸的态势较为明显, 影响和辐射作用越来越大。这说明以国家海洋局为代表的我国海洋科学学术国际影响力呈现增长的态势。  相似文献   

5.
红树林与气候变化耦合关系研究既是气候变化领域的研究热点,同时也是红树林领域的研究热点。本研究采用文献计量分析方法对中美红树林与气候变化耦合关系的研究现状和热点进行对比分析,探讨两国在该领域研究特征的异同。研究结果表明:(1)美国作为文献发表数量最高的国家,同样具有最强的学术影响力;中国拥有世界排名第三的发文数量,但在学术影响力方面与美国存在一定的差距。中美两国在该领域的发文量均呈现持续增长的趋势。(2)中美在该领域保持着较强的合作关系,且各自形成了较为广泛的国际合作网络。(3)中美两国的科学家均对气候变化背景下红树林生态系统的脆弱性以及红树林作为基于自然的解决方案在应对气候变化方面起到的作用等问题表现出浓厚的兴趣。但是,由于起步较晚,中国在红树林与气候变化领域相关研究的广度和深度较美国还存在一定的差距,需要进一步扩大国际合作,加强科研产出,提升学术影响力。本研究的相关成果将为我国红树林与气候变化领域的科研工作开展、政策制定及管理实践等提供信息参考。  相似文献   

6.
随着陆地金属矿产资源的日渐枯竭,深海多金属硫化物逐渐成为海洋矿产资源勘探的新趋势。文章介绍了全球主要海底多金属硫化物矿床的成因及分布特点,阐述了多个国际矿业公司和国际海洋组织对西南太平洋、大西洋和印度洋海底块状多金属硫化物勘探活动的最新进展。从海底多金属硫化物的金属品质、深海采矿的法律政策和环境保护等方面对海底多金属硫化物的开发前景进行探讨,并提出积极投身国际海底资源开发规章制定,进一步细化国内法律制度,为深海采矿提供良好的法律制度环境;提升深海治理能力,增强我国在深海领域的话语权;完善深海技术装备体系,提高深海开发创新能力等建议。  相似文献   

7.
国际海底矿产资源勘查与研究进展   总被引:2,自引:0,他引:2  
随着调查和研究的深入,世界各国对国际海底区域分布的多金属结核、富钴结壳、多金属硫化物和深海稀土几种深海固体矿产资源的关注程度日益增高,越来越多的国家为占有国际海底资源,加快了资源调查和评价的步伐,国际海底区域矿产资源的竞争形势愈加紧迫。通过调研的方式收集了大量资料,对国际海底区域多金属结核、富钴结壳、多金属硫化物和深海稀土几种深海矿产资源的分布和勘察现状进行评述,从而对国际海底矿产资源的研究趋势有所了解和把握。  相似文献   

8.
文章结合国际深海采矿的现状和中国现有国际海底区域矿区的情况,分析中国国际海底区域矿区采矿存在缺少法律依据、尚未完成矿区资源评价和"区域"放弃、深海采矿技术发展相对滞后、海洋环境影响评估尚有不足等问题;在此基础上提出未来发展建议,即开展与国际海底管理局的深度合作,在制定"区域"内矿产资源开发规章中有所作为;加快对中国国际海底区域的勘探工作,尽快完成矿区资源评价和"区域"放弃;跟踪国际深海采矿行业进展,加快推进中国深海采矿系统的建造并尽快试开采;继续加大深海采矿对海洋环境的影响研究,尽快形成深海采矿环境影响预测评价技术指南。  相似文献   

9.
21世纪是海洋的世纪。为探究进入21世纪后全球在海洋经济方面的研究演进路径和未来可能的研究热点,文章选取Web of Science核心数据库中主题为“Marine Economy”或“Marine Economics”的1 444篇期刊论文,利用Citespace软件分别进行科学合作网络分析、关键词共现分析和文献共被引分析。结果发现:进入21世纪以来,全球对海洋经济研究的关注度普遍提升。①美国、中国和英国构成了海洋经济领域研究的核心力量,但欧美国家之间机构合作较为密切,我国海洋研究机构国内外合作仍需加强,国际影响力仍需进一步提升;②现有海洋经济研究除聚焦渔业管理、海洋经济增长以及相关影响因素问题,还注重生态系统服务、环境保护等可持续性发展的问题;③近年来海洋经济研究相关热点开始转向小规模渔业管理、海洋生态环境保护、海洋产业空间布局和海洋休闲渔业,尤其是小规模渔业管理和海洋生态环境保护,是未来海洋经济研究需要重点关注的方向。  相似文献   

10.
吕阳 《海洋科学》2018,42(10):94-102
文章用文献计量与科学知识图谱方法呈现海洋药物研究态势与热点,旨在为海洋药物研究提供参考。本文以SCIE(Science Citation Index Expanded)为数据源,以1980~2017年海洋药物领域论文为研究对象,采用文献计量与知识图谱可视化分析方法,结合Excel、VOSviewer软件,对论文年代分布、研究机构、期刊、作者、高被引论文及研究热点进行分析。结果表明,海洋药物研究的热点方向为海洋天然产物、抗菌活性、细胞毒性、海绵等,应重点关注海洋天然产物及其抗菌药理作用的研究。世界范围内关于海洋药物研究的论文数量呈逐年上升趋势,美国在该领域研究占据绝对优势,其发文量、总被引和H指数均占绝对地位。该领域主要发文期刊为《Marine Drugs》、《Journalof Natural Products》。发文机构中中国科学院位列世界第一,但整体论文质量欠佳,中国在该领域研究水平有待加强,论文影响力仍需提高。  相似文献   

11.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

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A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.  相似文献   

15.
Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.  相似文献   

16.
A vertically integrated model has been used to study the tidal circulation and currents in the Gulf of Kachchh along the west coast of India. The model is fully nonlinear and uses a semiexplicit finite difference scheme to solve the basic hydrodynamic equations on a staggered grid. The model is forced by prescribing the tides along the open boundary of the model domain. The flow is simulated both with and without the presence of the proposed tidal barrage across the Hansthal Creek in the Gulf of Kachchh. The results show a considerable change in the behavior of the tidal flow in the presence of the barrage.  相似文献   

17.
<正>The typhoon,as a mature tropical cyclone that develops in the western part of the North Pacific Ocean with high wind speed and heavy rainfall,is one of the most lethal and costly of natural disasters for the densely populated countries of East Asia.It can be easily detected by space-borne sensors operated at microwave,visible or infrared bands(Liu et al.,2014).Synthetic Aperture Radar(SAR)is  相似文献   

18.
本文介绍了用国产D401型螯合树脂分离富集海水中铜、铅、锌、镉、铁、锰等痕量元素,并用原子吸收光谱仪测定其含量的方法。讨论了各元素的分离条件选择及干扰元素的影响,并与溶剂萃取法的结果作了比较。各元素检测的定量下限为:铜0.5μg/L、铅0.1μg/L、锌1.0μg/L、镉0.01μg/L、铁2.0μg/L、锰2.0μg/L。方法精密度在4—8%之间,回收率为90—102%。  相似文献   

19.
Soil core samples fromRhizophora mangleL. andAvicennia schauerianaStapf & Leech forests from south-eastern Brazil were analysed for their total organic matter content and their sugars, amino acid and amino sugars composition. Organic carbon and nitrogen contents were higher inAvicenniathan inRhizophorasoils. The contribution of sugars and amino acids to the total organic carbon pool was constant with depth inRhizophorasoils whereas inAvicenniasoils it increased. Spectral distribution of sugars and amino acids showed a dominance of Ca-affine monomers, particularly acidic amino acids, and the sugar arabinose. Biogeochemical indicators derived from ratios of individual sugar and amino acid monomers confirm previous studies which showed that organic matter in both soils is mainly of mangrove origin. The results further suggest accumulation of organic matter inRhizophorasoils and a continuing degradation of organic matter inAvicenniasoils. The latter may thus release more nutrients to adjacent ecosystems thanRhizophorasoils.  相似文献   

20.
Orange roughy Hoplostethus atlanticus are unusual fish. They form dense aggregations that have fuelled lucrative fisheries at great depths (600–1 400 m), especially off Namibia, New Zealand and Australia. They are thought to be very long-lived (>100 years, maturity at 22 – 40 years), and to have exceptionally low natural mortality (M = 0.045–0.064 year?1) and slow growth rates (K = 0.055–0.070 year?1). In addition, they spawn large eggs and have low fecundity. These factors combine to make orange roughy highly susceptible to overfishing; most stocks are below 30% of pristine levels. Assessments are obtained from indices of catch rate and trawl, acoustic and egg surveys. Acoustic estimates are the most direct, but are confounded by the species' low target strength (?50 to ?53 dB)–attributable to the wax-filled swim bladder. Extracellular wax esters are stored in abundance and comprise mostly mono-unsaturated fatty acids, with low concentrations of the ω-3 fatty acid family. This unusual composition (resultant from the species' diet) ensures neutral buoyancy. Stock separation has been inferred mainly from biological studies, but genetic studies have also found differences among stocks within New Zealand and Australia. Deep-water habitat may be damaged by trawling operations and may take many years to recover, so in some quarters there is a call for a portion of suitable habitat to be set aside for preservation. Although Namibian orange roughy are shallower, smaller and younger than those in other stocks, the Namibian fishery sustained high catches for only a few years before quotas were reduced, from 12 000 to 1 875 tons. Three management lessons are suggested for developing orange roughy fisheries based on the Namibian experience: (1) imposition of catch limits during exploratory fishing; (2) starting the acoustic surveys earlier in the fishery, if possible; (3) greater reliance on trends in catch rate until a survey series has been established.  相似文献   

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