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831.
我国湿地景观研究现状、存在的问题与发展方向 总被引:11,自引:0,他引:11
湿地景观研究是近十余年来新兴的热点领域,极大地推进了湿地学科发展.但是,由于湿地景观研究体现的是湿地与景观方法有机结合,其在发展过程中还存在许多问题.本文在对我国湿地景观研究现状系统分析基础上,重点阐明了湿地景观概念、分类、遥感信息提取精度、多源数据可比性、结构与格局研究方法、景观过程与功能研究内容与尺度等制约湿地景观研究的主要问题.并指出了未来发展方向:(1)重视湿地景观分类研究;(2)重视湿地景观破碎化研究;(3)重视发展基于过程和功能的景观格局研究方法;(4)重视多尺度湿地生物多样性研究;(5)重视湿地景观管理研究. 相似文献
832.
热液区沉积物接受了大量热液物质的输入,其矿物组成及地球化学空间分布特征是多金属硫化物勘探的有效指标。由于重力作用,洋中脊区域沉积物主要分布于低洼和平坦地形区。为了探索地形因素对热液区沉积物分布的影响规律,本文通过ArcGIS提出了一种基于地形数据的海底热液区沉积物分布趋势预测方法,并对西南印度洋中脊龙角区地形数据进行了分析,包括沉积物重力搬运方向提取、沉积物汇集量估算、海底沟谷提取和沉积物源区划分。通过与研究区底质解译结果进行对比验证发现,预测结果与研究区内沉积物的实际分布范围较为吻合,表明本方法在一定程度上可以有效地指示地形影响下海底热液区沉积物的分布情况。本方法对海底硫化物矿产勘探工作具有一定指导意义,可为海底沉积物取样站位设置与海底硫化物成矿远景区圈定提供参考依据。 相似文献
833.
月球测绘在月球探测中的应用 总被引:7,自引:1,他引:7
根据探月历史概述了月球测绘与月球探测的关系、月球探测的焦点和我国探月计划;分析研究了月球 测绘的关键技术;论述了月球测绘在月球探测中的应用。 相似文献
834.
835.
随着海洋调查技术的发展和海洋研究的深入,基于深潜器平台的近海底调查在海洋调查与研究中的综合应用日趋常态。基于这一背景,本文介绍了搭载于"发现"号缆控水下机器人(remotely operatedvehicle,ROV)的近海底综合声学调查系统及其在台西南冷泉区的应用实例。基于"发现"号ROV平台的近海底综合声学调查系统主要由R2Sonic2024多波束测深系统,模块一体化的侧扫声纳-浅地层剖面系统和水下综合定位与导航系统构成。该系统的配置极大地扩展和完善了"发现"号ROV的近海底调查能力,实现了近海底多波束、侧扫和浅剖等声学数据的同步采集和快速融合处理。基于本套系统在南海冷泉区的综合应用,本文对其工作流程进行了介绍,并对所获得一系列成果进行了初步分析。结果表明,近海底综合探测系统的应用为南海冷泉区的识别、海底地形地貌特征分析以及空间规模量化研究等内容提供了不可或缺的基础资料。本套系统的配置和成功应用,有效地提高了我国的近海底调查和作业能力。 相似文献
836.
Michael P. Bishop John F. Shroder Jr. Radoslav Bonk Jeffrey Olsenholler 《Global and Planetary Change》2002,32(4)
Globally significant interactions between climate, surface processes, and tectonics have recently been proposed to explain climate change and mountain building. Assessing climate-driven erosion processes and geomorphic change in high-mountain environments, however, is notoriously difficult. In the western Himalaya, the coupling of climate, surface processes, and tectonics results in complex topography that frequently records the polygenetic nature of topographic evolution over the last 100 ka. Depending upon the erosional history of a particular landscape, temporal overprinting of geomorphic events can produce unique topographic properties which define the spatial complexity of the topography. Field work coupled with analysis of the topography using digital elevation models (DEMs) enable low- and high-frequency spatial patterns and scale-dependent properties of the topography to be detected and associated with geomorphic events caused by climate and tectonic forcing. We conducted spatial analysis of the topography at Nanga Parbat in northern Pakistan to demonstrate the utility of geomorphometry and to characterize dramatic geomorphic change over the past 100 ka. Results indicate rapid river incision, extensive glaciation, and variable denudation rates by mass movement, glaciation, and catastrophic flood flushing. Furthermore, topographic and chronologic evidence indicate that glaciation is strongly controlled by the southwestern monsoon, and that modern fluvial systems are still responding to tectonic forcing and deglaciation. Scale-dependent analysis of the topography revealed that different erosion processes uniquely alter the spatial complexity of the topography, such that the greatest mesoscale relief appears to be caused by glaciation. Collectively, our results indicate that topographic development in the western Himalaya is inherently polygenetic in nature, with glaciation, fluvial and slope processes all playing important roles at different times, and that they can do so sequentially on the same portion of the landscape. Given the rapidity of major changes in climate and glaciation over the last 100 ka, the landscape cannot be in steady-state. 相似文献
837.
838.
S.A.P.L. Cloetingh P.A. Ziegler P.J.F. Bogaard P.A.M. Andriessen I.M. Artemieva G. Bada R.T. van Balen F. Beekman Z. Ben-Avraham J.-P. Brun H.P. Bunge E.B. Burov R. Carbonell C. Facenna A. Friedrich J. Gallart A.G. Green O. Heidbach A.G. Jones L. Matenco J. Mosar O. Oncken C. Pascal G. Peters S. Sliaupa A. Soesoo W. Spakman R.A. Stephenson H. Thybo T. Torsvik G. de Vicente F. Wenzel M.J.R. Wortel TOPO-EUROPE Working Group 《Global and Planetary Change》2007,58(1-4):1
TOPO-EUROPE addresses the 4-D topographic evolution of the orogens and intra-plate regions of Europe through a multidisciplinary approach linking geology, geophysics, geodesy and geotechnology. TOPO-EUROPE integrates monitoring, imaging, reconstruction and modelling of the interplay between processes controlling continental topography and related natural hazards. Until now, research on neotectonics and related topography development of orogens and intra-plate regions has received little attention. TOPO-EUROPE initiates a number of novel studies on the quantification of rates of vertical motions, related tectonically controlled river evolution and land subsidence in carefully selected natural laboratories in Europe. From orogen through platform to continental margin, these natural laboratories include the Alps/Carpathians–Pannonian Basin System, the West and Central European Platform, the Apennines–Aegean–Anatolian region, the Iberian Peninsula, the Scandinavian Continental Margin, the East-European Platform, and the Caucasus–Levant area. TOPO-EUROPE integrates European research facilities and know-how essential to advance the understanding of the role of topography in Environmental Earth System Dynamics. The principal objective of the network is twofold. Namely, to integrate national research programs into a common European network and, furthermore, to integrate activities among TOPO-EUROPE institutes and participants. Key objectives are to provide an interdisciplinary forum to share knowledge and information in the field of the neotectonic and topographic evolution of Europe, to promote and encourage multidisciplinary research on a truly European scale, to increase mobility of scientists and to train young scientists. This paper provides an overview of the state-of-the-art of continental topography research, and of the challenges to TOPO-EUROPE researchers in the targeted natural laboratories. 相似文献
839.
张赤军 《大地测量与地球动力学》1997,(1)
根据近年来精化大地水准面的研究结果,对人们比较关心的5个方面的问题加以综述和探讨:(1)大地水准面的定义;(2)精化大地水准面的作用;(3)由似大地水准面改化为大地水准面;(4)海面地形对大地水准面的影响及其改正;(5)高程异常中的零阶项及其误差 相似文献
840.
The increasing need for distributed hydrological modelling leads to an intense use of spatially distributed predictions of physically based models, such as TOPMODEL as addressed here. The ability of these models to reproduce the internal behaviour of catchments physically is increasingly tested through field experiments (geochemical investigation, distributed measurements network, etc.). This paper will show that, in the case of TOPMODEL, an implicit approximation remains in the classic derivation of the equations that consists in neglecting the surface of saturated areas with respect to the total surface of the catchment. This simplifying, though unnecessary, approximation leads to a systematic underestimation of the catchment water storage deficit and to divergence in the water budget accounting. This may also significantly change the predicted ratio between subsurface and surface water fluxes in the total discharge. An analytical solution is suggested that leads to water balance accounting which is better defined, and more consistent in comparison with field water storage recording. It is expected that this work will ensure more accurate TOPMODEL predictions, consistent with the assumptions of the model. This will then improve the interpretation of comparisons between results of simulation and field experiments. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献