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1.
国际全球变化研究发展态势文献计量评价 总被引：1，自引：0，他引：1
全球变化研究是国际上地球系统综合研究的重大跨学科研究领域.随着全球环境问题的日益突出,国际上先后组织发起了全球环境变化研究的四大科学计划WCRP、IGBP、IHDP、DIVERSITAS及其组成的地球系统科学联盟ESSP,开展对全球变化和地球系统科学的研究.当前,全球变化问题不仅是科学界关注和研究的问题,也是政治界、经济界都关注的重大问题.科技文献能够反映科学前沿的发展动态.对SCIE和SSCI数据库收录的全球变化研究文献进行统计,从文献计量学的角度,分析国际全球变化研究领域的发展态势,了解中国全球变化研究的国际影响力.可以看出:国际上全球变化研究的论文数量一直呈增长趋势,以地球科学多学科、生态学、环境科学、自然地理学、植物学等学科领域为主.中国自2000年以来在该领域的发文数量增长较快,特别是中国科学院的发文量已进入国际前列,但中国在该研究领域尚缺少高影响力的论文. 相似文献
2.
国际及中国地球科学发展态势文献计量分析 总被引：7，自引：0，他引：7
以SCI、ESI（基本科学指标数据库）、GEOREF等数据库为统计分析源,对1993—2003年国际及中国地球科学的发展现状和发展态势从文献计量学的角度进行统计分析,分析了国际地球科学论文产出的主要领域、国家、机构、科学家和期刊,对中国地球科学论文产出的主要领域进行比较分析,并通过论文产出、被引频次、篇均被引频次和国际1%顶尖论文数量对比反映中国的科学影响力。结果表明,国际环境科学和生态学研究论文增长很快,占地球科学相关主题领域论文的比例也比较大,但中国生态学研究论文无论从占国内22个学科论文产出的比例,还是从占全球该领域的比例来说都有较大差距;中国地质科学领域研究重点在地球化学、金属矿产和能源的经济地质学,但在环境地质学领域研究相对较少,而国际上环境地质学研究论文的发展已经大大高于传统的地质学论文。 相似文献
3.
对科研成果产出的定量科学评价,可以了解科研队伍的现状和科研的影响力。利用文献计量学方法,采集了2000—2004年SCI数据库中中国学者发表的地球科学论文,统计分析中国地球科学SCI论文的产出和被引用情况,以了解中国当前具有国际学术交流能力和SCI论文发表能力的地球科学研究队伍的现状和科研成果的国际影响力。分析结果表明,2000—2004年中国的国际地学研究论文数量以年均21.87%的速度递增,5年的论文篇均被引频次为2.57。地球科学二级学科领域SCI论文产出数量从高到低依次为：地质科学、地理科学、空间物理学、环境科学、地球物理学、大气科学、海洋科学、地球化学。在中国地学研究队伍中,中国科学院系统和教育部系统发表的论文数量最多,论文数量合计占中国国际地学论文总数的83.58%。中国当前具有国际学术交流能力和SCI论文发表能力的地球科学研究队伍人数在8 000人左右。 相似文献
4.
本文基于Web of Science数据库，针对2000-2019年钻井液领域文献进行对比和可视化分析，梳理了钻井液年发文量、发文国家、研究热点和研究机构等信息。结果表明：从年发文量来看，2012年之前全球钻井液发文量增长较慢，而2012年之后钻井液发文量出现猛增。美国发文数量最多，达到1803篇，篇均被引频次达到22.06次。中国发文量为1586篇，但是篇均被引频次只有8.55，论文质量与美国差距巨大。从研究方向来看，能源燃料是钻井液领域的重点研究方向。从关键词共现来看，流变性能、纳米材料、天然气水合物等是钻井液研究的相关热点。期刊《Journal of Petroleum Science and Engineering》在钻井液领域的刊文量最大，达到426篇，是钻井液领域最具影响力的期刊。 相似文献
5.
卫星重力与地球重力场研究是国际大地测量学的重要研究领域,不仅带动了大地测量学本身的发展,也在其他相关研究领域取得了重要的科学应用.以2000年1月至2020年9月的20年Web of Science核心合集数据库中关于该领域的科学论文为研究对象,使用文献计量的方法,应用CiteSpace软件对当前研究现状、近年来发展脉络以及研究热点进行分析.结果 表明,关于卫星重力和地球重力场的文献数量总体上逐年上升,2016年以来维持较高的水平,其中美国、德国以及中国的发文量位居前三位;发文量排名前三的研究机构分别为中国科学院、加州理工学院和美国国家航空航天局;我国在卫星重力及地球重力场领域的研究力量相对集中,中国科学院、武汉大学以及中国科学院大学发文数占中国总数的75.36％;利用GRACE数据和球谐函数构建高精度地球重力场模型,反演局部质量变化是当前国际研究热点.得益于卫星重力观测数据,全球重力场模型得到了实质性改进. 相似文献
6.
区域研究：全球变化研究的重要途径 总被引：7，自引：1，他引：7
区域研究是全球变化研究的重要途径。国际上南部非洲、南亚、东亚、东南亚4个地区及若干重大区域研究项目如 LBA、AMMA、MAIRS及ProMed等典型案例研究表明：区域研究是全球变化研究的基础，区域的实验、模拟、分析是全球环境变化研究的有效方法。区域研究应关注：陆地表面过程、海岸带的陆—海相互作用过程、区域气候变化过程等关键过程对全球变化的响应及作用；区域边缘现象、阈值与突变问题；区域人类活动对全球变化的有序适应等。有必要制订国际区域研究计划，实施地球系统的区域观测，建立区域研究的集成新方法、区域实验与尺度转换方法，建立基于数理基础的区域地球系统模型和数值模拟等新方法。 相似文献
7.
全球变化与人类活动的相互作用--我国下阶段全球变化研究工作的重点 总被引：28，自引：7，他引：21
全球环境变化与可持续发展是当今人类社会面临的两大重要挑战。IGBPⅡ在探索地球系统变化规律的同时,力图将全球变化与可持续发展更紧密地结合,为人类社会的可持续发展提供科学背景和依据。根据国际全球变化研究发展的动向与我国的具体情况,今后我国全球变化与人类活动相互作用研究的重点应放在那些兼备显著区域特色和国际影响力的重大科学问题上。其中值得着重解决的10个科学问题包括：水循环与水问题、人类活动与区域碳循环过程、季风亚洲的人类活动与气候集成、土地利用/土地覆盖变化与陆地生态系统变化、人类活动与大气气溶胶、边缘海及海陆过渡带与人类活动、全球变化的影响与适应性、过去环境变化与中华文明、建设全面小康社会与温室气体减排国际谈判的科学支持、全球变化与人类活动相互作用研究基础信息平台建设。 相似文献
8.
我国的地球系统科学研究向何处去 总被引：27，自引：8，他引：19
近15年来,全球变化与地球系统科学研究在中国广泛开展,我国科学家越来越积极地参加各项国际计划。当前,一些重大的国际计划正在进入其新阶段（如IGBP-II,IODP）,恰好我国也正在制定科技发展中长期规划,迫切需要回顾我国地球系统科学的现状并探讨其今后方向。尽管中国作者的国际论文数量在增长,我国地球系统科学落后于国际的差距仍有拉大的趋势：国际前沿的许多热点问题,在中国尚未提上日程;中国学者在国际计划中早期多有贡献,但在项目总结中却很少有份。为此,提出 3点建议：（1）中国地球科学家应当扩大视野、立足本国、面向全球;（2）应当注意国际前沿动向,促进地学与生命科学在分子水平上的结合;（3）中国的地球科学,应当从以描述为主向探索理的方向发展。我们不应当满足于向国际学术界输出"原料",而要积极参加地球系统科学中关键问题的理论探讨。 相似文献
9.
国际生态系统研究发展态势文献计量分析 总被引：4，自引：0，他引：4
生态系统研究是地球系统科学的重要组成部分,近年来,各国和各相关研究机构对生态系统的研究力度不断加大.利用Thomson Data Analyzer、NetDraw和Aureka等文献计量工具,结合Pathfinder算法对SCIE和SSCI数据库中国际生态系统研究相关文献进行了分析.在对主要国家和机构的发文进行统计分析后发现:美国、德国和英国等国的生态系统研究论文的综合影响力较高,其中美国是国际生态系统研究合作的中心;加州大学伯克利分校、美国国家海洋与大气管理局和法国农业科学研究院等机构的论文影响力较大;美国农业部、德国马普学会、华盛顿大学和瑞典隆德大学是国际生态系统研究的中心;中国生态系统研究论文在总量上优势明显,但整体论文质量不高;国际生态系统研究的主要研究热点集中在珊瑚礁生态系统研究、气候变化研究和生态系统管理等方面. 相似文献
10.
冻土是冰冻圈的重要组成部分，其对全球变暖敏感且对工程稳定性影响显著，近年来全球科学家更多地关注这一研究领域。作为世界冻土大区的中国，对冻土学科的发展和动态尤其重视。本文基于文献计量的方法，对近五年（2012-2016）冻土学领域发表的SCI（E）/CPCI收录论文进行统计分析，得到该领域在全球的研究力量分布。同时，分别从冻土工程、冻土力学、冻土环境、冻土物理这四个方向加以区分，得到其不同机构与科学家论文发表情况。从论文产出的角度，宏观地反映了冻土科学在这五年中的发展脉络与国际影响力。这一工作可为全面了解近期该领域的研究发展动态提供数据参考。 相似文献
11.
记述了新生代深海冷水碳酸盐泥丘近期的9个重要研究事件;总结了冷水泥丘具有全球海洋(大陆斜坡为主)分布、形态各异、冷水枝状珊瑚构筑泥丘的特点;介绍了冷水泥丘形成的(地质流体渗流和微生物作用)内因及(海底牵引底流作用)外因两种主要观点.对2005年IODP 307航次实施的北大西洋Porcupine Seabight冷水泥丘大洋钻探工作初步成果进行了编译,公布了中国科学家在碳氧同位素方面的初步实验结果.实验结果显示上新世中期以来的2 Ma里冷水碳酸盐泥丘启动和发育过程中存在2次碳氧同位素偏移事件(Ⅰ和Ⅱ),碳氧同位素偏移事件Ⅰ与泥丘的启动相呼应,暗示北大西洋古海洋气候发生巨大变化,可能与北极冰盖极盛有关. 相似文献
12.
A. Foubert D. Van Rooij D. Blamart J.-P. Henriet 《International Journal of Earth Sciences》2007,96(1):141-158
Three provinces, characterized by the presence of carbonate mounds interpreted as cold-water coral banks have been reported
in Porcupine Seabight, SW of Ireland and were recently subjected to many detailed studies. This contribution discusses the
use of X-ray imagery and physical properties in deciphering palaeoceanographic, sedimentological and biological processes.
Physical property core logging and X-ray imagery are used to identify and describe sedimentation regimes and so their respective
palaeoceanographic and palaeoclimatological settings in two mound provinces, respectively the Belgica mound province and the
Magellan mound province. Both provinces show at present time clear differences in the hydrodynamic environment. This study
confirms that also during the past the oceanographic and sedimentological environment of both provinces differ clearly. Impacts
of glacial–interglacial variations and locally derived ice rafting events (IRE), comparable with the North Atlantic Heinrich
events (HE) have been recognized in both provinces. Moreover, the combination of X-ray imagery, magnetic susceptibility, gamma
density and P-wave velocity makes it possible to estimate the coral content and coral distribution in unopened cores localized
on top of carbonate mounds. A comparison between on-mound and off-mound cores in both provinces allowed revealing some mechanisms
of mound evolution and coral growth versus time. 相似文献
13.
L. Maignien D. Depreiter A. Foubert J. Reveillaud L. De Mol P. Boeckx D. Blamart J.-P. Henriet N. Boon 《International Journal of Earth Sciences》2011,100(6):1413-1422
The Gulf of Cadiz is an area of mud volcanism and gas venting through the seafloor. In addition, several cold-water coral
carbonate mounds have been discovered at the Pen Duick escarpment amidst the El Arraiche mud volcano field on the Moroccan
margin. One of these mounds -named Alpha mound- has been studied to examine the impact of the presence of methane on pore-water
geochemistry, potential sulphate reduction (SR) rate and dissolved inorganic carbon (DIC) budget of the mound in comparison
with off-mound and off-escarpment locations. Pore-water profiles of sulphate, sulphide, methane, and DIC from the on-mound
location showed the presence of a sulphate to methane transition zone at 350 cm below the sea floor. This was well correlated
with an increase in SR activity. 13C-depleted DIC at the transition zone (−21.9‰ vs. Vienna Pee Dee Belemnite) indicated that microbial methane oxidation significantly
contribute to the DIC budget of the mound. The Alpha mound thus represents a new carbonate mound type where the presence and
anaerobic oxidation of methane has an important imprint on both geochemistry and DIC isotopic signature and budget of this
carbonate mound. 相似文献
14.
Xianghui Li Chiduru Takashima Akihiro Kano Saburo Sakai Yunhua Chen Baoliang Xu Iodp Expedition Scientists 《第四纪科学杂志》2011,26(2):178-189
Stable isotopes and element compositions of the fine‐grained matrix were measured for IODP Expedition 307 Hole U1317E drilled from the summit of Challenger Mound in Porcupine Seabight, northeast Atlantic, to explore the palaeoceanographic and palaeoclimatic background to development of the deep‐water coral mound. The 155 m long mound section was divided into two units by an unconformity at 23.6 mbsf: Unit M1 (2.6–1.7 Ma) and Unit M2 (1.0–0.5 Ma). Results from 519 specimens show a difference in δ13C value between Unit M1 (?0.6‰ to ?5.0‰) and Unit M2 (?1.0‰ to 1.0‰), but such a distinct difference was not seen in δ18O values (1.0‰–2.5‰), CaCO3 content (40–60 wt%), Sr/Ca ratio (2.0–8.0 mmol mol?1), and Mg/Ca ratio (10.0–20.0 mmol mol?1) through the mound. Positive δ18O and negative δ13C shifts at the mound base are consistent with the oceanographic changes in the northeast Atlantic at the beginning of the Quaternary. The positive δ13C regression in Unit M2 suggests a linkage to the mid Pleistocene intensified glaciation in the Northern Hemisphere. Warm Mediterranean Upper Core Water of Mediterranean Outflow Water, Eastern North Atlantic Water and cold Labrador Sea Water of North Atlantic Deep Water are key oceanographic features that cause spikes and shifts in stable isotope and element composition. However, the stable isotope values of the sediment matrix could not primarily record the glacial–interglacial eustatic/temperature change, but indirectly indicate current regimes of the intermediate oceanic layer where the coral mound grew. Similarly, elemental ratios and CaCO3 content may not represent the productivity and temperature of surface sea water, respectively, but superpose the fractions from both surface and bottom water. It is concluded that palaeoceanographic change coupled to the Pleistocene glacial/interglacial cycles is a key control on the geochemical stratigraphy of the matrix sediments of the carbonate mound developed in Porcupine Seabight. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
15.
Carbonate budget of a cold-water coral carbonate mound: Propeller Mound,Porcupine Seabight 总被引：1，自引：0，他引：1
Boris Dorschel Dierk Hebbeln Andres Rüggeberg Christian Dullo 《International Journal of Earth Sciences》2007,96(1):73-83
High resolution studies from the Propeller Mound, a cold-water coral carbonate mound in the NE Atlantic, show that this mound
consists of >50% carbonate justifying the name ‘carbonate mound’. Through the last ~300,000 years approximately one third
of the carbonate has been contributed by cold-water corals, namely Lophelia pertusa and Madrepora oculata. This coral bound contribution to the carbonate budget of Propeller Mound is probably accompanied by an unknown portion of
sediments buffered from suspension by the corals. However, extended hiatuses in Propeller Mound sequences only allow the calculation
of a net carbonate accumulation. Thus, net carbonate accumulation for the last 175 kyr accounts for only <0.3 g/cm2/kyr, which is even less than for the off-mound sediments. These data imply that Propeller Mound faces burial by hemipelagic
sediments as has happened to numerous buried carbonate mounds found slightly to the north of the investigated area. 相似文献
16.
Morphology and environment of cold-water coral carbonate mounds on the NW European margin 总被引：6，自引：0，他引：6
A. J. Wheeler A. Beyer A. Freiwald H. de Haas V. A. I. Huvenne M. Kozachenko K. Olu-Le Roy J. Opderbecke 《International Journal of Earth Sciences》2007,96(1):37-56
Cold-water coral carbonate mounds, owing their presence mainly to the framework building coral Lophelia pertusa and the activity of associated organisms, are common along the European margin with their spatial distribution allowing them
to be divided into a number of mound provinces. Variation in mound attributes are explored via a series of case studies on
mound provinces that have been the most intensely investigated: Belgica, Hovland, Pelagia, Logachev and Norwegian Mounds.
Morphological variation between mound provinces is discussed under the premise that mound morphology is an expression of the
environmental conditions under which mounds are initiated and grow. Cold-water coral carbonate mounds can be divided into
those exhibiting “inherited” morphologies (where mound morphology reflects the morphology of the colonised features) and “developed”
morphology (where the mounds assume their own gross morphology mainly reflecting dominant hydrodynamic controls). Finer-scale,
surface morphological features mainly reflecting biological growth forms are also discussed. 相似文献
17.
The Magellan mound province in the Porcupine Basin 总被引：5，自引：0，他引：5
V. A. I. Huvenne W. R. Bailey P. M. Shannon J. Naeth R. di Primio J. P. Henriet B. Horsfield H. de Haas A. Wheeler K. Olu-Le Roy 《International Journal of Earth Sciences》2007,96(1):85-101
The Magellan mound province is one of the three known provinces of carbonate mounds or cold-water coral banks in the Porcupine
Seabight, west of Ireland. It has been studied in detail using a large and varied data set: 2D and 3D seismic data, sidescan
sonar imagery and video data collected during ROV deployment have been used to describe the mounds in terms of origin, growth
processes and burial. The aim of this paper is to present the Magellan mounds and their setting in an integrated, holistic
way.
More than 1,000 densely spaced and mainly buried mounds have been identified in the area. They all seem to be rooted on one
seismic reflection, suggesting a sudden mound start-up. Their size and spatial distribution characteristics are presented,
together with the present-day appearance of the few mounds that reach the seabed. The underlying geology has been studied
by means of fault analysis and numerical basin modelling in an attempt to identify possible hydrocarbon migration pathways
below or in the surroundings of the Magellan mounds.
Although conclusive evidence concerning the processes of mound initiation proves to be elusive, the results of both fault
analysis and 2D numerical modelling failed to identify, with confidence, any direct pathways for focused hydrocarbon flow
to the Magellan province. Diffuse seepage however may have taken place, as drainage area modelling suggests a possible link
between mound position and structural features in the Hovland-Magellan area. During mound development and growth, the interplay
of currents and sedimentation seems to have been the most important control. Mounds which could not keep pace with the sedimentation
rates were buried, and on the few mounds which maintained growth, only a few corals survive at present. 相似文献
18.
Cold-water corals represent an intriguing paleoceanographic archive with a great potential to reconstruct high-resolution paleoenvironmental changes. Compared to those of shallow-water corals, proxies derived from cold-water corals have been complicated by biologically mediated vital effects. The oxygen and carbon stable isotope compositions of cold-water coral skeletons are more depleted than the expected carbonate-seawater equilibrium values by 4‰~6‰ and about 10‰, respectively. Therefore, it is necessary to correct for the vital effects before using δ18O as a temperature proxy. The principles and methods of reconstructing paleotemperature variations of intermediate and deep oceans using oxygen and carbon isotopes of cold-water corals are reviewed, as well as three existing cold-water coral calcification models and their advantages and disadvantages. It is suggested that further micro-scales analysis and targeted experiments are required to clarify the calcification processes of cold-water corals. 相似文献
19.
D. Van Rooij V. A. I. Huvenne D. Blamart J.-P. Henriet A. Wheeler H. de Haas 《International Journal of Earth Sciences》2009,98(4):849-863
The genesis and evolution of cold-water coral banks along the Northeastern Atlantic margin is known to be influenced by several
factors, among which the palaeotopography and nature of the coral settling surface, the presence of bottom currents and sediment
supply. In this paper, a case study is presented of the Enya mound cluster, located in the southernmost tip of the Belgica
mound province, west of Ireland. Below this mound cluster, seismic stratigraphy revealed a yet unmapped local unconformity
RD1b, being part of a composite erosion event (RD1). As such, from the Late Miocene to Late Pliocene, at least two erosional
events have incised the margin, ending with the final RD1a “moundbase” unconformity, acting as a base for the Enya mounds.
During the Quaternary the mounds became outgrown and were covered by a mounded contourite drift. In addition, they are closely
associated with a cluster of seabed pockmarks. The bottom current regime which became active since the Middle Pleistocene
has certainly influenced the fate of this mound cluster. The occurrence of the pockmarks seems to be related to relatively
recent fluid migration processes, however leaving an open question if any previous seepage phases were involved in the growth
or initiation of the coral banks. 相似文献
20.
Judith Totman Parrish Ethan G. Hyland Marjorie A. Chan Stephen T. Hasiotis 《Sedimentology》2019,66(1):32-52
Carbon, oxygen and clumped isotope (Δ47) values were measured from lacustrine and tufa (spring)‐mound carbonate deposits in the Lower Jurassic Navajo Sandstone of southern Utah and northern Arizona in order to understand the palaeohydrology. These carbonate deposits are enriched in both 18O and 13C across the basin from east to west; neither isotope is strongly sensitive to the carbonate facies. However, 18O is enriched in lake carbonate deposits compared to the associated spring mounds. This is consistent with evaporation of the spring waters as they exited the mounds and were retained in interdune lakes. Clumped isotopes (Δ47) exhibit minor systematic differences between lake and tufa‐mound temperatures, suggesting that the rate of carbonate formation under ambient conditions was moderate. These clumped isotope values imply palaeotemperature elevated beyond reasonable surface temperatures (54 to 86°C), which indicates limited bond reordering at estimated burial depths of ca 4 to 5 km, consistent with independent estimates of sediment thickness and burial depth gradients across the basin. Although clumped isotopes do not provide surface temperature information in this case, they still provide useful burial information and support interpretations of the evolution of groundwater locally. The findings of this study significantly extend the utility of combining stable isotope and clumped isotope methods into aeolian environments. 相似文献