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Susceptibility Assessment of Landslides Caused by the Wenchuan Earthquake Using a Logistic Regression Model

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Journal of Mountain science 2010年第3期7卷 234-245页

作者： SU Fenghuan key laboratory of Mountain Hazards and Land Surface Processes Chinese Academy of Sciences Chengdu China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Graduate University of the Chinese Academy of sciences Beijing China

The Wenchuan earthquake on May 12.2.08 caused numerous collapses,landslides,barrier lakes,and debris *** susceptibility mapping is important for evaluation of environmental capacity and also as a guide for post-earthquake *** this paper,a logistic regression model was developed within the framework of GIS to map landslide *** County,a heavily affected area,was selected for the *** of landslides was prepared by interpretation of multi-temporal and multi-resolution remote sensing images(ADS4. aerial imagery,SPOT5 imagery and TM imagery,etc.) and field *** Certainly Factor method was used to find the influencial factors,indicating that lithologic groups,distance from major faults,slope angle,profile curvature,and altitude are the dominant factors influencing *** weight of each factor was determined using a binomial logistic regression *** susceptibility mapping was based on spatial overlay analysis and divided into five *** faults have the most significant impact,and landslides will occur most likely in areas near the *** of the area has a high or very high susceptibility,located in the northeast,south and southwest,including 65.3% of all landslides coincident with the *** susceptibility map can reveal the likelihood of future failures,and it will be useful for planners during the rebuilding process and for future zoning issues.

关键词： Landslide susceptibility WenchuanEarthquake GIS logistic regression certainty factor

Assessment of coral bleaching using symbiotic zooxanthellae density and satellite remote sensing data in the Nansha Islands,South{2. Sea

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Chinese science Bulletin 2011年第10期56卷 1031-1037页

作者： LI Shu,YU KeFu,CHEN TianRan,SHI Qi & ZHANG HuiLing CAS key laboratory of Marginal Sea Geology,South{2. Sea Institute of Oceanology,Chinese Academy of sciences Guangzhou 510301,{4. CAS key laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China

Coral bleaching,characterized by a significant loss of symbiotic zooxanthellae,is the primary cause of mass coral mortality and reef degradation throughout the *** characteristics,processes,and resistance of corals to bleaching varies significantly and is dependent on environmental *** documented a mass coral bleaching event in June 2.07 at the Meiji and Zhubi Reefs,Nansha Islands (NS),South china Sea using ecological surveys and measurement of coral zooxanthellae density and sea surface temperatures (SST).More than 35 species of corals (between 0-2. m in depth) were *** bleached corals accounted for 15.6% of total corals in the investigated *** branching corals Pocillopora and Acropora were the most vulnerable species whereas the massive corals Porites and Favia were more tolerant of the high ***,we found no evidence of bleaching in Agariciidae corals suggesting that this family is resistant to thermal *** bleached corals had lost 72.-90% of their symbiotic ***,corals that had no visual signs of bleaching had also lost 31%-53% of their zooxanthellae suggesting that most corals were experiencing the early stage of *** monthly mean SST during June 2.07 was 30.8°C,the highest since *** on measurements of SST and the Hotspots and DHW data (NOAA),we conclude that it the extremely high SSTs triggered this coral bleaching *** results suggest that the previously accepted temperature thresholds used to predict coral bleaching based on satellite data are likely to underestimate the extent and intensity of coral bleaching,at least in the NS.

关键词：珊瑚礁南沙群岛中国南海卫星遥感数据漂白黄藻密度共生

APPLICATION OF TWO-DIMENSIONAL WAVELET TRANSFORM IN NEAR-SHORE X-BAND RADAR IMAGES

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Journal of Hydrodynamics 2011年第2期23卷 179-186页

作者： FENG Xiang-bo YAN Yi-xin, ZHANG Wei state key {2. of Hydrology-Water Resources and Hydraulic Engineering and College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

Among existing remote sensing applications, land-based X-band radar is an effective technique to monitor the wave fields, and spatial wave information could be obtained from the radar images. Two-dimensional Fourier Transform （2.D FT） is the common algorithm to derive the spectra of radar images. However, the wave field in the nearshore area is highly non-homogeneous due to wave refraction, shoaling, and other coastal mechanisms. When applied in nearshore radar images, 2.D FT would lead to ambiguity of wave characteristics in wave number domain. In this article, we introduce two-dimensional Wavelet Transform （2.D WT） to capture the non-homogeneity of wave fields from nearshore radar images. The results show that wave number spectra by 2.D WT at six parallel space locations in the given image clearly present the shoaling of nearshore waves. Wave number of the peak wave energy is increasing along the inshore direction, and dominant direction of the spectra changes from South South West （SSW） to West South West （WSW）. To verify the results of 2.D WT, wave shoaling in radar images is calculated based on dispersion relation. The theoretical calculation results agree with the results of 2.D WT on the whole. The encouraging performance of 2.D WT indicates its strong capability of revealing the non-homogeneity of wave fields in nearshore X-band radar images.

关键词： non-homogeneity X-band radar two-dimensional Wavelet Transform (2.D WT) dispersion relation nearshore wave field

博斯腾湖流域山区地表径流对近期气候变化的响应

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山地学报 2010年第2期28卷 206-211页

作者：孙占东 Christian Opp 王润高前兆中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室马尔堡大学地理系中国科学院城市环境研究所中国科学院寒区与旱区环境与工程研究所

近年来,在全球和区域气候变化影响下,新疆博斯腾湖主要产流区开都河出山径流呈现异常波动,引起气候变化研究的关注。鉴于产流区复杂地形和径流补给特征以及传统观测资料的不足,借助雷达、微波及可见光等多源遥感数据从山区降水、积雪和... 详细信息

近年来,在全球和区域气候变化影响下,新疆博斯腾湖主要产流区开都河出山径流呈现异常波动,引起气候变化研究的关注。鉴于产流区复杂地形和径流补给特征以及传统观测资料的不足,借助雷达、微波及可见光等多源遥感数据从山区降水、积雪和冰川等方面与出山径流变化关系进行比较来揭示径流突变原因。结果表明,产流区平均径流深与降水量关系的转变是引起出山径流异常波动直接原因;进一步的冰川变化分析显示,径流深的波动主要由冰川融水径流变化引起:2.世纪80年代中期后的温度上升加速了山顶冰川消融,导致1987～2.02.的径流增加和湖泊水位升高;1984.2.00年间,流域山顶冰川面积消退近4.%,随着分布在较低海拔,对温度升高最敏感的中小冰川的消失,冰雪消融带来的径流增加效应开始减弱;2.02.后,在流域气温、降水等变化并不显著的情况下,出山径流量却急剧降低,反映了特定冰川分布条件地区在气候变暖中融水径流先升后降的现象。

关键词：天山博斯腾湖气候变化地表径流水文响应

Ocean primary productivity estimation of china Sea by remote {2.

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Progress in Natural science:Materials International 2005年第7期15卷 627-632页

作者： PAN Delu, GUAN Wenjiang, BAI Yan and HUANG Haiqing (laboratory of Ocean Dynamic Processes and Satellite Oceanography, Second Institute of Oceanography of state Oceanic Administration, Hangzhou 310012.{2.) laboratory of Ocean Dynamic Processes and Satellite Oceanography Second Institute of Oceanography of State Oceanic Administration Hangzhou 310012 China

Ocean primary productivity is a key parameter in the research of global carbon cycle, ocean biological resources, and in evaluation of the feature and quality of ocean biological environment. Traditional shipboard measurement which is costly and time-consuming is impossible to obtain the spatial and temporal information on primary productivity on a large scale in a short period of time. Satellite remote {2. is an effective strategy to acquire the ocean information in near real time. Here we propose a model special for china Sea based on the concept of primary productivity using in situ primary productivity and environmental data from 1984.to 1990, and discuss every modeling parameter which can be retrieved by remote {2. in detail. The reliability of this model is tested by in situ data, and the comparison of other primary productivity models is made. We also analyze the temporal and spatial distribution of china Sea primary productivity in 2.00. From our analysis the satellite remote {2. data have been proved very useful for ocean primary productivity study.

关键词： remote sensing ocean primary productivity.

Bi-directional normalized difference vegetation index: concept and application

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Progress in Natural science:Materials International 2002年第2期 37-41页

作者： LI Xiaowen , GAO Feng , WANG Jindi , YANG Hua, A. STRAHLER and C. SCHAAF( Research Center for remote sensing and Department of Geography, Beijing Normal University, Beijing {2., china Department of Geography and Center for remote sensing, Boston University, Boston MA02.15, USA) Research Center for remote sensing and Department of Geography，Beijing Normal University，Beijing {2.，china Department of Geography and Center for remote sensing，Boston University，Boston MA02.15，USA Department of Geography and Center for remote sensing，Boston University，Boston MA02.15，USA Research Center for remote sensing and Department of Geography，Beijing Normal University，Beijing {2.，china

The data products of land surface bi-directional reflectance distribution function (BRDF) from the space-borne Polarization and Directionality of the Earth Reflectance (POLDER) of France and the Moderate Resolution Imaging Spectroradiometer (MODIS) of USA are available recently, but the atmospheric correction for meeting the requirement of quantitative remote sensing is still a very difficult problem. This paper presents a concept: bi-directional normalized difference vegetation index (Bi-NDVI), in order to consider simultaneously the effects of both land surface BRDF and atmospheric path scattering. An atmospheric quality index is thus defined for satellite multi-angular observations. The quality of MODIS/BRDF data products can be improved notably through iterative inversion weighed by this index.

关键词： bi-directional reflectance normalized difference vegetation index atmospheric correction.

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三维地形数据的简化和空间分析的研究

系统仿真学报 2004年第3期16卷 608-611页

作者：张立强杨崇俊刘冬林中国科学院遥感应用研究所遥感科学国家重点实验室北京100101

全球地形场景的建模是一个极富有挑战性的课题。地形动态简化是构建三维地形场景和虚拟现实的重要内容,基于视相关的地形裁剪技术是动态简化庞大地形数据的重要方法。本文根据地球椭球的特性,提出了在当前LOD层次下,实时裁剪视景体中的... 详细信息

全球地形场景的建模是一个极富有挑战性的课题。地形动态简化是构建三维地形场景和虚拟现实的重要内容,基于视相关的地形裁剪技术是动态简化庞大地形数据的重要方法。本文根据地球椭球的特性,提出了在当前LOD层次下,实时裁剪视景体中的地形数据的算法。精确拾取地形点的三维大地坐标是进行正确的三维空间分析和查询操作的基础,也是3DGIS研究中的一个难点;而可视性分析是三维空间分析的重要研究内容。本文给出了这些的问题的算法。实验证明,这些算法具有较好的实用性。

关键词：全球地形可视化地形裁剪 3D大地坐标可视域分析

Satellite SAR interferometric observations of displacements associated with urban subsidence in Suzhou, Eastern china

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Progress in Natural science:Materials International 2002年第10期 80-82+84页

作者： WANG Chao, ZHANG Hong, LIU Zhi, CHENG Suozhong and LU Guonian(1. LARSIS, Institute of remote sensing Applications, Chinese Academy of {2.s, Beijing 100101, china 2. Department of Geography, Nanjing Normal University, Nanjing 2.0097, china) LARSIS Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101China Department of Geography Nanjing Normal University Nanjing 210097 China

SAR interferometry (InSAR) has a high potential for surface displacement mapping in the range from millimeter to meter. In this paper the potential of ERS-1/2.SAR interferometry for mapping subtle land subsidence has been investigated. A time series of ERS-1/2.SAR data from February 1993 to February 2.00 is collected from measurements taken in Suzhou city, Jiangsu Province, china, eight ERS-1/2.SAR images are used to create seven interferograms, and three differential interferograms are produced using the three-pass method, which clearly show the spatial extent of land subsidence. The deformation maps are validated by leveling surveys, the correlation coefficient and standard deviation between them are 0. 94. and 0.1706 respectively. Based on seven benchmarks, the subsidence rates are estimated, the overall trends are in close agreement with InSAR results. The results of study show that for the mapping of land subsidence in urban environments InSAR has a strong potential due to its cost-saving, high res

关键词： SAR interferometry land subsidence Suzhou.

Saline-alkali land in the Yellow River Delta: amelioration zonation based on GIS

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Journal of Geographical sciences 2001年第3期11卷 313-320页

作者： GUAN Yuan-xiu, LIU Gao-huan, WANG Jin-feng (state key {2. of Resources and Environment Information System, Institute of Geographic sciences and Natural Resources Research, CAS, Beijing 100101,{4.) state key {2. of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research CAS

Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present situation of saline-alkali land is monitored by remote sensing image processing. Causes for land salinization are analyzed, especially the two {2. factors, ground water depth and its mineralization degree, are analyzed by using long-term observation data. Previously, zonation of saline-alkali soil was made descriptively and artificially. Based on the present situation of saline-alkali land, ground water depth and ground water mineralization degree, the zonation of saline-alkali land for amelioration in the Yellow River Delta was completed quantitatively. Four different types of saline-alkali land amelioration zones are delineated, namely, easy ameliorated zone, relatively difficult ameliorated zone, difficult ameliorated zone and unfavorable ameliorated zone. Countermeasures for ameliorating saline-alkali soils are put forward according to ecological conditions of different saline-alkali land zones.

关键词： GIS the Yellow River Delta saline-alkali land zonation