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生物多样性 2004年第1期12卷 206-212页

作者：王襄平王志恒方精云北京大学环境学院生态学系

基于我国的地貌特征、数字高程模型 (DEM )以及数字地形模型 (DTM)等资料 ,参考以往的研究文献 ,给出了我国主要山峰和山脉的分布图及相关的地理信息 ,为我国的宏观生态学和生物地理学研究提供基本的山地资料。

关键词：山峰山脉地貌中国分布图地理信息中国

福建武夷山自然保护区地形对毛竹(Phyllostachys pubescens)林分布的影响

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生物多样性 2004年第1期12卷 75-81页

作者：郑成洋方精云何建源北京大学环境学院生态学系福建武夷山国家级自然保护区管理局武夷山354300

用PC ORD 4 .0软件对保护区内 31个毛竹 (Phyllostachyspubescens)林样方进行聚类分析 ,把毛竹林划分成9类。利用保护区 1980年航空相片、1998年和 2 0 0 0年LandsatTM卫星影像 ,并结合保护区森林资源调查资料 ,绘制武夷山保护区毛竹林... 详细信息

用PC ORD 4 .0软件对保护区内 31个毛竹 (Phyllostachyspubescens)林样方进行聚类分析 ,把毛竹林划分成9类。利用保护区 1980年航空相片、1998年和 2 0 0 0年LandsatTM卫星影像 ,并结合保护区森林资源调查资料 ,绘制武夷山保护区毛竹林分布图。利用保护区 1 5 0 0 0 0的地形图数字化 10 0m等高距生成数字高程模型 (DEM ) ,并从中获取海拔、坡向、坡度等地形参数 ,对毛竹林分布进行空间叠加分析。结果表明 :保护区内毛竹纯林和毛竹—甜槠 (Castanopsiseyrei)林面积最大 ,分别占毛竹林总面积的 4 0 .6 %和 2 0 .3%。分析毛竹林与海拔的关系时得出 ,海拔 5 0 0 - 70 0m范围内毛竹林面积最大 ;随着海拔升高 ,毛竹林面积逐渐减少 ,Shannon Wiener指数 (H′)增加 ;毛竹最大胸径减小。毛竹在东南坡和西北坡分布的面积比例最大。随着坡度的增加 ,毛竹分布的面积减少。

关键词：毛竹地形影响生物多样性武夷山分布图

河北小五台山主要植被类型的分布与地形的关系:基于遥感信息的分析

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生物多样性 2004年第1期12卷 146-154页

作者：刘增力郑成洋方精云北京大学环境学院生态学系

小五台山是河北省最高峰 ,具有较完整的暖温带植被垂直带谱。本文通过野外群落植被调查 ,结合由TM遥感影像解译 1 5 0 0 0 0地形图制作的DEM数据而得到的植被图 ,分析了小五台山主要植被群落的分布状况及其与地形的关系。结果表明 ,... 详细信息

小五台山是河北省最高峰 ,具有较完整的暖温带植被垂直带谱。本文通过野外群落植被调查 ,结合由TM遥感影像解译 1 5 0 0 0 0地形图制作的DEM数据而得到的植被图 ,分析了小五台山主要植被群落的分布状况及其与地形的关系。结果表明 ,小五台山从低海拔到高海拔 ,依次出现灌丛、阔叶林、针阔混交林、暗针叶林、矮林、灌丛、草甸等植被类型。森林景观的面积最大 ,占总面积的 6 0 .7% ;平均斑块面积最大的是阔叶林和亚高山草甸 ,斑块破碎化最严重的是水体和针阔混交林。不同的植被类型在不同的地形条件下分布特点不同 ,林地在北坡所占面积比例 (占总面积的 75 % )远大于南坡 (4 6 % ) ,说明水分条件是小五台山森林分布的限制因子之一 ;灌丛和草甸与林地相反。随海拔高度的变化 ,不同植被类型的分布面积比例发生变化 ,出现替代现象 ,形成植被垂直带谱。由于坡度的影响 ,增加了带谱内植被组成的复杂性。

关键词：小五台山植被 DEM 遥感植被图多样性

高黎贡山种子植物物种丰富度沿海拔梯度的变化

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生物多样性 2004年第1期12卷 82-88页

作者：王志恒陈安平朴世龙方精云北京大学环境学院生态学系

物种丰富度沿海拔梯度的分布格局成为生物多样性研究的热点。为探讨中尺度区域物种丰富度沿海拔梯度的分布 ,本文以高黎贡山为研究对象 ,利用该地区的地方植物志资料 ,结合通过GIS生成的区域数字高程模型(DEM)数据 ,分析了该区域全部种... 详细信息

物种丰富度沿海拔梯度的分布格局成为生物多样性研究的热点。为探讨中尺度区域物种丰富度沿海拔梯度的分布 ,本文以高黎贡山为研究对象 ,利用该地区的地方植物志资料 ,结合通过GIS生成的区域数字高程模型(DEM)数据 ,分析了该区域全部种子植物和乔木、灌木、草本三种生活型种子植物物种丰富度的垂直分布格局以及物种密度沿海拔梯度的变化特征。结果表明 :(1)全部种子植物和不同生活型植物物种丰富度随着海拔的升高呈现先增加后减小的趋势 ,最大值出现在海拔 15 0 0 - 2 0 0 0m的范围 ;(2 )物种密度与海拔也呈现单峰曲线关系 ;(3)物种丰富度和物种密度分布格局的形成主要受海拔所反映的水、热状况组合以及物种分布的边界影响。

关键词：物种丰富度物种密度生活型垂直格局海拔梯度地形植物

Advances on Active Tectonics Research

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earthquake Research in china 2001年第4期15卷 346-353页

作者： Chen Yong, Chen Qifu, and Li Juancenter for Analysis and Prediction, china Seismological Bureau, beijing 100036, china center for Analysis and Prediction China Seismological Bureau Beijing 100036 China

The tectonic movement at human scale has not been fully understood yet, especially for active tectonics, although it is the basis to study natural hazards and environmental variations. Many national and international scientific plans related closely to active tectonics research have been made in the past ten years. This paper briefly summarized the background of the undertaking of active tectonics research, its advances and existing problems, and the key points in its future studies are also pointed out. The emerging of new technologies like the earth Observing System, digital Seismology and so on provides unusual opportunities for tectonic research. It is emphasized, however, that careful analyses and building up of new theoretical frame are sill the key problems for studies of active tectonics, especially for active tectonics in china’s continent.

关键词： Active tectonics

River Boundaries Extraction in Mountain Areas for SAR Images with Fusing GIS Information

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River Boundaries Extraction in Mountain Areas for SAR Images...

CENOZOIC BASIN EVOLUTION, STRUCTURAL STYLES OF THE QAIDAM AND AN ESTIMATE OF DENUDATION IN ADJACENT MOUNTAIN SYSTEMS, NORTHEAST QINGHAI—TIBETAN PLATEAU

2011 CIE International Conference on Radar(RADAR 2011)

作者： Wang Xiaoliang 1 2 Li Chunsheng 2 and Wu Renbiao 1 3 1 Tianjin Key Laboratory for Advanced Signal Processing Civil Aviation University of china Tianjin 300300 P.R.china 2 School of Electronics and Information Engineering Beihang University beijing 100191 china 3 Defence Key Laboratory for ATR Shenzhen University Shenzhen 518060 china

River boundaries extraction on SAR images is valuable for flood monitoring. Traditional methods usually failed in high relief areas. We proposed a river boundaries extraction method to conquer the difficulty to discri... 详细信息

关键词： SAR Information Fusion Segmentation Active Contour Model Level Set

来源： cnki会议评论

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地学前缘 2000年第S1期7卷 212-212页

作者： Tang Liangjie, Jin Zhijun, Zhang Mingli (Basin & Reservoir Research center, University of Petroleum, beijing 102200, china)

Qaidam basin is located at northeast Qinghai—Xizang (Tibet) plateau, and surrounded by east Kunlun, south Qilian and Altun mountain systems. The purpose of this paper is to study the Cenozoic basin evolutionary stages, structural styles of the Qaidam, and the denudation in adjacent mountain systems through seismic profile interpretation and complemented by field observation. The Qaidam basin has experienced two tectonic stages of Paleogene—early Miocene (65～12Ma) and late Miocene—present (12～0Ma). The former is characterized by differential uplift of the mountains and subsidence of the basin, and the latter by intense compression, wrench, thrusting and folding. The compressional structural styles are mainly distributed in the Circle Hero—Range Depression of southwest Qaidam, such as Nanyishan, Youquanzi, Younan, Youshashan anticline belts and thrust faults. The wrench structural styles of the northern Qaidam include en echelon uplifts (fault—block outcrops) such as Seshitengshan, Luliangshan, Xitieshan and Eimnikshan, which are mainly composed of pre\|Sinian and Paleozoic rocks; en echelon anticlines such as Lenghu—Nanbaxian belts; and en echelon depressions such as Kunteyi, Senan and Yibei depressions, which are mainly composed of Mesozoic and Cenozoic rocks.

关键词： basin evolution structural styles denudation Qaidam basin Qinghai—Tibetan plateau

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数字省建设技术体系研究

计算机科学 2003年第2期30卷 52-54页

作者：池天河王雷王钦敏陈崇成中国科学院地理科学与资源研究所北京100101 福建省空间信息工程研究中心福州350002

The construction of digital Province and digital City is the base and important factor of digital earth. During the construction of digital Province,the technology framework of digital province is one of the key problems. This paper summarizes current construction status of digital province technology framework and content and key technology of digital fujian.

关键词：数字省建设技术体系信息基础设施信息共享计算机网络 “数字福建”

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超巨磁电阻薄膜在光探测上的新应用

物理 2004年第5期33卷 367-371页

作者：常雷蒋毅坚王茺朱绍将张国勇张鹏翔昆明理工大学光电子新材料研究所昆明650051 北京工业大学国家产学研激光技术中心北京100022

混合价态钙钛矿锰氧化物在外界温度变化和磁场作用下表现出巨大的磁电阻 (colossalmagnetoresistance,简记为CMR)效应 ,引起了人们的广泛关注 .由于CMR材料在传感器、探测器以及硬盘读出磁头等应用器件研发上极具潜力 ,科学家们对其进... 详细信息

混合价态钙钛矿锰氧化物在外界温度变化和磁场作用下表现出巨大的磁电阻 (colossalmagnetoresistance,简记为CMR)效应 ,引起了人们的广泛关注 .由于CMR材料在传感器、探测器以及硬盘读出磁头等应用器件研发上极具潜力 ,科学家们对其进行了大量研究 .文章在简单介绍CMR材料结构和机理的基础上 ,着重报道了作者利用CMR薄膜的激光感生热电电势 (LITV)制备激光功率 /能量探测器和利用电阻在室温附近的巨大变化研制光热辐射探测器 (bolometer)

关键词：超巨磁电阻薄膜光探测器激光感生热电势效应能量探测器

PRELIMINARY RESULTS OF earthQUAKE MOMENT TENSOR INVERSION IN WESTERN china

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地学前缘 2000年第S1期7卷 172-172页

作者： Gao Yuan 1, Suzan van der Lee 2, Domenico Giardini\+2, Jochen Braunmiller\+2, Zheng Si\|hua\+3[WT5,5”BX](1 center for Analysis and Prediction, CSB, beijing 100036, china,E\|mail:gaoyuan @ seis,*** 2 Institute of Geophysics, ETH\|Honggerberg, 8093

The goal of this study is to determine earthquake source processes of moderate to strong earthquakes in Western china using data recorded by the digital broadband stations in and near china. There are 12 broadband stations on the chinese mainland. This paper used a kind of moment tensor inversion method to study the large earthquakes in the Xizang (Tibet) region of *** this study, we first ported and tested a moment\|tensor inversion code and then applied the technique to a large (magnitude M s=7.9) earthquake in Xizang region of china. The inversion for the earthquake moment tensor is performed in the frequency domain by fitting long\|period observed spectra to synthetic spectra calculated. For details of the method refer to Giardini and Beranzoli (1992). As part of the project, we extended the library of synthetics by including local (>100km) and teleseismic distances (2000kmearth rising, on average, more than 4000 meters above sea level. The high topography is the result of the collision between the Indian and Asian tectonic plates which is also the cause for the area’s high seismicity rate. As a preliminary study, the moment tensors were obtained for the large earthquake ( M s=7.9) of 8 Nov 1997 in Xizang region using data from five stations. The result is similar to the Harvard CMT solution; for strike, dip and rake, this paper obtained 343, 76 and -177 degrees, respectively, while the Harvard CMT values are 348, 88 and 159. The moment magnitude estimate of Harvard is only 0.1 unit larger than my estimate of M w=7 4.. The fit in the frequency domain (phase and amplitude) suggests the reasonable result. At long periods the earthquake depth is generally not well resolved. Inversions for several trial depths, however, show a clear variance minimum for centroid depths (the average depth over the entir

关键词： earthquake moment tensors magnitude topography Western china