SPOT卫星数据图像处理方法及应用

使用ENVI图像处理软件进行SPOT卫星数据与TM数据进行复合制作卫星影像图技术研究，经反复试验，成功地研制成了既有明显色彩差异，又具有较高分辨率的假彩色遥感图像，为卫星遥感影像图开发利用提供方法技术。文章主有关的图像处理方法及其应用作简单介绍，仅供同行参考。     

利用光学图像与雷达图像提取地质构造信息的IHS融合方法研究

光学图像和雷达图像的IHS融合方法是提取构造信息的一种较好的信息增强方法,这种方法既可以保留波谱信息,又可以增加图像的立体效果。本文以鄂尔多斯盆地杭锦旗—东胜地区一带为研究区,选用光学TM图像和雷达JERS图像进行了IHS融合处理,重点研究了光学图像波段的选取以及雷达图像的预处理过程,并在融合过程中注意通过光学TM图像和雷达JERS图像之间的直方图匹配,以降低其融合后图像的变化差异度,从而使此种融合方法更适用于研究区的构造信息提取。     

长江三峡库区地质灾害遥感图像信息处理及其监测和评估

长江三峡作为世界上最大的水利工程,引起了世界的广泛关注。水库堤岸的长度、水库容载力、三峡移民数量以及其对生态环境的影响都成为议论的焦点。最引人注目的是长江两岸存在大量的地质灾害,如：滑坡、崩塌等,其中有些大型灾害体目前仍处于活动状态,这将给三峡工程的安全与库岸稳定性以及库区生态环境带来深远的影响。因此,采用3S和多时相TM、SPOT、ERS—SAR和RADARSAT等图像集成新技术来快速有效地监测、研究和评估地质灾害对三峡工程以及周边环境的影响,为地质灾害的预防和治理提供科学依据,本成果具有重要的学术意义和实用价值。     

西昆仑山崇测冰川区多源遥感影像的冰川信息提取方法研究

冰雪独有的性质与特性使得基于遥感影像对其进行信息提取成为可能,如何进行精准的冰雪信息提取是冰雪时空变化研究的关键和基本要求。利用多源遥感影像（TM、IRS-P5和SAR）对西昆仑山崇测冰川区的冰川进行信息提取,采用不同分类方法和数据融合方法,分别针对光学影像和微波影像进行处理,提取冰川信息并进行比较分析。结果表明：面向对象分类方法是最优的冰川信息提取方法;图像融合处理有助于提高冰川信息的提取精度,特别是多光谱和高分辨率图像融合后再分类,提取效果更为理想。     

Regional assessment of landslide impact in the Three Gorges area, China, using ASTER data: Wushan-Zigui

This paper is focussed on the hazard impact of landslides in the Three Gorges, and represents the progression of our ongoing study on regional land instability assessment in the Three Gorges area using imagery data from the Advanced Spaceborne Thermal Emission Radiometer (ASTER). The key development here is the establishment of a model that integrates land instability with several factors that can relate hazard to human life, such as slope failures occurring in proximity to built-up areas and roads, and areas of high landslide risk along the bank of Yangtze and its major tributaries. The method correctly identifies some of the known destructive landslides in the region, like Qianjiangping and Huangtupo, as belonging to areas of potentially high landslide impact. Our results suggest that several population centres, including the towns of Wushan and Badong, are rated at high landslide hazard levels. This study highlights the importance of differentiating between landslide types within susceptibility assessment, and identifies those locations in the Three Gorges where the probability of landslide occurrence with negative impact to life and property is greatest.     

三峡库区重庆市丰都县滑坡灾害危险性评价

在对三峡库区丰都县滑坡灾害调查和统计分析的基础上,初步概括了滑坡灾害的分布特征和主要影响因素,进而利用综合信息模型评价了丰都县滑坡灾害的危险性,将丰都县滑坡灾害的危险性划分为高危险区、中危险区、低危险区和基本安全区4个等级。其中,高危险区和中危险区分别占全县总面积的2.6%和23.2%,主要分布在长江干流及其支流两岸的居民相对集中区,不同规模的滑坡灾害经常发生,因此潜在危害也很大;低危险区占全县总面积的47.5%,偶有小规模的滑坡灾害发生;基本安全区占全县总面积的25.5%,在人为因素的诱发下可能偶有小规模的滑坡灾害发生,适合于大型工程建设和城镇居民点建设。     

三峡水库建成后长江中下游防洪战略思考

三峡水库建成后,长江中下游防洪形势显著改善,但由于经济社会发展,防洪要求的提高和江湖关系的变化,长江防洪形势发生了一些新的变化。以1954年和1998年典型大洪水为例,分析了三峡水库建成后长江中下游防洪形势出现的新变化,讨论了长江中下游蓄滞洪空间格局调整及江湖关系变化对于防洪的影响。根据长江水沙变化、河道演变、水库群调控和分蓄洪区使用几率变化等出现的新问题,提出未来防洪战略及对策。结果表明:三峡建成后,百年一遇以下洪水防御形势明显好转,而百年一遇以上特大防洪的防洪形势仍然严峻,洪水风险主要转移到水库群上;今后需要在加强蓄滞洪区建设的基础上,重点推动防洪非工程措施建设,以减轻特大洪水带来的灾害损失。     

The regional distribution regularity of landslides and their effects on the environments in the Three Gorges Reservoir Region, China

On the basis of research and analysis of the landslide system of the Three Gorges Reservoir area, this paper systematically analyzes and studies the temporal–spatial distribution law of landslides of this reservoir area and their impacts on environment of this area. The paper puts forward that the temporal–spatial distribution of this area’s landslides is mainly controlled by lithologic characters of strata, geological structure, valley landscape, and types of bank slope structure; landslide deformation and failure have such characteristics as simultaneity, laggardness, cyclical instability, and stage. Besides, the paper systematically analyzes and studies the main impacts of landslide on environment and points out that landslides and collapses will bring about relatively serious impacts on relocation and layout of cities and towns along the banks. These impacts mainly include the increase of relocation investment, number of migrants, and compensation for losses. Much attention and evaluation should be paid to the impacts of Xintan Landslide and Lianziya Landslide—large landslides near the Dam—on the construction and safety of the Three Gorges Project. However, landslides have relatively small impacts on shipping and reservoir capacity. The above-mentioned research is of great guiding significance for the construction of the Three Georges Project, planning and construction of cities and towns along the banks, and protection of geological environment.     

三峡库区巫山县城二郎庙小区岩溶引起的地质灾害危险性研究

三峡库区移民迁建中发现的岩溶问题是一个重大工程地质问题。巫山县新城二郎庙小区是地质灾害监测预警示范区,那里的三叠系嘉陵江组灰岩在特殊的气候、水文和地质环境下遭受了强烈的岩溶作用,岩体结构变得非常复杂,完整的灰岩变为层状碎裂岩体、岩溶角砾岩、泥质条带和残坡积角砾层。不同的地貌部位具有不同的岩溶特点和强度,总体规律性是由西向东、剖面下部至上部岩溶作用增强,其中陡坡下地形由陡变缓的转折地带和冲沟下部是岩溶作用最强烈的地带。岩溶作用形成了各种微地貌和特殊的岩体组合格局。岩溶导致岩体的力学强度和稳定性不断降低,加上其他自然因素和人为因素作用可能产生地面不均匀沉降、地裂缝、滑坡、崩塌、泥石流和地面塌陷地质灾害,这些问题必须在移民迁建以及将来城镇运行过程中引起高度重视。     

Assessment and zonation of regional crustal stability in and around the dam region of the Three Gorges Project on the Yangtze River

 The scale of the Three Georges Project (TGP) on the Yangtze River ensures that it will have enormous social and economic consequences. Determining the safety of the TGP is an essential consideration, and conducting the assessment and zonation of regional crustal stability has a crucial role in determining the success or failure of the TGP in the future. In this paper, the assessment of regional crustal stability, places much emphasis on tectonic stability and the stability of partial foundations (rock and soil masses) and surface slopes (which include landslides, collapses, etc.) related to fracture activity is also taken into consideration. The evaluation and zonation of regional crustal stability was conducted on two scales and scopes: the dam region and the vicinity of the TGP (about 310 000 km²), and the dam region of the TGP (about 30 000 km²). On the basis of tectonic zonation and present crustal stress field analysis, fuzzy mathematics was used to perform quantitative and comprehensive evaluations of crustal stability, and then the zonation of crustal stability in the study region, combined with a theoretical geological study, was made. The results of the assessment and zonation of the crustal stability can be summarized as follows: (1) the general crustal stability of the dam region is in a less stable-stable state and the Sandouping dam site is on a relatively stable landmass; and (2) the Sandouping dam site is on an ancient integrated granite body belonging to a stable (I) landmass. Therefore, from the view of assessment and zonation of regional crustal stability, a large-scale hydropower station can be constructed at Sandouping. Received: 8 September 1995 · Accepted: 25 February 1997     

长江三峡库区土壤与水系沉积物Cd地球化学特征

对长江三峡库区段不同介质中Cd的分布特征和长江水系沉积物在垂向、横向剖面上的元素分布特征的研究发现，残坡积型土壤与长江干流水系沉积物Cd含量差异较大，水系沉积物具明显的高Cd异常；各个沉积时期的水系沉积物中均存在Cd异常，上游来源的Cd是引起三峡库区水系沉积物高Cd异常的主要因素；人类活动对土壤和水系沉积物中Cd的含量影响明显，在厂矿、码头、生活垃圾场等地区土壤中Cd的含量远高于一般地区土壤中Cd的含量，城市排污水系沉积物Cd的含量也高于长江干流水系沉积物Cd的含量。自然源是沿长江流域Cd异常普遍存在的根本原因，而人为源却有可能是高Cd异常主要沿长江干流及支流两岸大中城市分布的重要影响因素。     

江汉平原周老镇钻孔砾石统计及其与长江三峡贯通的关系

对江汉平原周老镇钻孔砾石层砾石的粒度和砾态进行统计和分析的结果表明：砾石的风化程度普遍较高,砾石的扁度、球度、磨圆度、砾态参数（F／ψ）和各轴分选系数均符合河流相沉积物的特征。通过分析砾石粒度和砾态的变化曲线,可将其划分为3个阶段。阶段Ⅰ和Ⅱ的平均砾径、中值砾径、扁度、球度和砾态参数（F／ψ）相差不大,而阶段Ⅲ与阶段Ⅰ、Ⅱ相差很大,阶段Ⅲ的水动力条件、沉积物比阶段Ⅰ、Ⅱ显著增强并混杂了远源物质。结合周老镇钻孔岩性及钻孔砾石含量和江汉平原第四系岩相剖面特征判断,在阶段Ⅲ109．5-117．0m（0．97～1．12Ma．B．P．）处钻孔的沉积环境发生了重大改变,江汉平原水系发生了重要调整,可能是长江贯通三峡。