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1.
简述陆地卫星多光谱扫描(MSS)影象的特点,着重介绍陆地卫星多光谱扫描影象适用于中、小比例尺的土地资源凋查  相似文献   
2.
INTRODUCTION Land use and land cover change (LUCC) has become an increasingly important aspect of global environmental change and is a multi-disciplinary subject where geophysicist, bio-physicists and socio-economists meet one another. Land cover is an expression of human activities and, as such, changes with changes in land use and management (Louisa and Antonio, 2001), and land cover change could be regarded as change in biotic diversity, actual and potential productivity, soil quality…  相似文献   
3.
Abstract

Internet access to Landsat and other remotely sensed data sets, at little or no cost to the public, is an important emerging trend. This has many implications, including more widespread application of remotely sensed data and improved educational opportunities at all levels. The overall goal of improving public access is the “demystification” of remote sensing, which will result in a greater awareness about the benefits and limitations of the technology and its more frequent inclusion in public discourse. This paper outlines several programs that provide the public with access to free or inexpensive Landsat data sets via the Internet.  相似文献   
4.
蒋世章  季青  汪康  董玉娟 《大众科技》2009,(10):100-102
以福州市为研究区,采用单窗算法,对Landsat ETM+第6波段的遥感数据,进行地表温度反演,得到地表温度分布图,分析了地表温度分布规律,并提出减轻热岛效应措施。结果表明:福州市城市热岛效应显著,单窗算法可以较好的反映城市热场的空间分布,地表温度与归一化植被指数(NDVI)有良好的负相关关系,与地面下垫面密切相关。  相似文献   
5.
东江流域近20年土地利用变化的时空差异特征分析   总被引:8,自引:2,他引:6  
任斐鹏  江源  熊兴  董满宇  王博 《资源科学》2011,33(1):143-152
根据1990年、2000年和2009年3期LandsatTM/ETM影像的土地利用分类结果,综合运用地理信息系统空间分析工具、变化指数对比分析等技术和方法,对东江流域1990年-2009年间的土地利用变化及其区域差异特征进行了分析。结果表明:①1990年以来,东江流域土地利用变化的特点表现为城市化过程显著、非城镇用地结构变化明显,以及林地和灌草地大为减少的总体特征;②流域的上游、中游、下游三个区域在1990年-2000年和2000年-2009年两个时段,城镇用地增加量表现出相同的空间分异特征,而年增长率却表现出不同的空间分异特征,其中非城镇用地的转化在3个区域差异明显,自然植被退缩的程度表现为下游>上游>中游;③东江流域2000年-2009年时段的土地利用变化速度较之1990年-2000年时段整体上有所缓和,但在程度上仍具有区域差异性,显示出土地利用程度进一步向高度集约化发展;④人口增加、经济增长、区域发展政策的变化叠加在区域自然差异之上是东江流域土地利用变化及区域差异产生的主要原因。  相似文献   
6.
Archive Fever     
Abstract

The science of cartography went through revolutionary changes in the post-World War II period. In the near future the new types of artifacts and materials produced by the cartographers of this period will form the basis for the study of the history of modern cartography. Computer software, new computational devices, computer hardware, and complex mathematical algorithms all need to be preserved in a way that allows researchers access to the concepts and techniques that make up the cartography of today and the future. The following paper is a case study in the preservation of collections that are typically not part of the traditional materials found in map libraries. Although this paper is pragmatic in nature and focuses in particular on the software and algorithms found in the John Snyder Collection of satellite mapping materials now in the Library of Congress, it also addresses the many conceptual and theoretical problems that arise in the preservation of what the author calls “foundational collections” in the history of cartography.  相似文献   
7.
吴溪  郭斌  陈忠升  史文娇 《资源科学》2018,40(11):2260-2269
不透水面是影响城市生态环境的关键因子,及时、精确地掌握不透水面的动态变化对城市的发展规划具有重要指导意义。本文以环胶州湾为例,基于1990年、1995年、2000年、2005年、2011年Landsat TM影像和2016年Landsat OLI影像,采用线性光谱混合分析和决策树相结合的方法分析了环胶州湾不透水面格局演变过程。结果表明:①本文提取的1990—2016年环胶州湾不透水面丰度与验证数据的决定系数R2均在0.70以上,均方根误差RMSE均在16.70%以下。②环胶州湾不透水面面积由1990年的105.17km2增长到2016年的620.02km2,总的扩展方向为由南向北、向东和向西移动。③1990年城阳区成为辅助市区发展的重心,现由城阳区逐渐向黄岛区、崂山区、即墨区和胶州市发展。  相似文献   
8.
Lakes have played a critical role in providing water and ecosystem services for people and other organisms in China for millennia. However, accelerating climate change and economic boom have resulted in unprecedented changes in these valuable lakes. Using Landsat images covering the entity of the country, we explored the changes in China’s lakes and the associated driving forces over the last 30 years (i.e. mid-1980s to 2015). We discovered that China’s lakes have changed with divergent regional trends: in the sparsely populated Tibetan Plateau, lakes are abundant and the lake area has increased dramatically from 38 596 to 46 831 km2 (i.e. increased by 8235 km2, or 21.3%), whereas, in the densely populated northern and eastern regions, lakes are relatively scarce and the lake area has decreased from 36 659 to 33 657 km2 (i.e. decreased by 3002 km2, or 8.2%). In particular, severe lake decreases occurred in the Mongolia-Xinjiang Plateau and the Eastern Plain (−2151 km2). Statistical analyses indicated that climate was the most important factor controlling lake changes in the Tibetan Plateau, the Yun-Gui Plateau and the Northeast Plain. However, the strength of climatic control on lake changes was low in the Eastern Plain and the Mongolia-Xinjiang Plateau, where human activities, e.g. impoldering, irrigation and mining, have caused serious impacts on lakes. Further lake changes will exacerbate regional imbalances between lake resources and population distribution, and thus may increase the risk of water-resource crises in China.  相似文献   
9.
Abstract

Since the late 1960s, the United States government has invested more than $1 billion in designing, launching, and operating the Landsat (land satellite) series of Earth-observing satellites. Global change researchers, geologists, and environmental scientists have used images gathered by the satellites for purposes ranging from human health research, energy exploration, and pollution detection to agricultural assessments, urban growth monitoring, and earthquake lineament studies.

The earliest data were captured on a digital medium called wide-band video tape (WBVT). However, two decades of unsound media storage conditions and a poorly maintained processing system have left the physically deteriorating WBVTs with no mechanism for interpretation. A national treasure was in jeopardy. With seed money from the National Aeronautics and Space Administration (NASA), the U.S. Geological Survey (USGS) began a project to rescue the data. More than 21,000 tapes from the 1970s have been transcribed to stable, archival media, preserving the data for future studies in Earth System Science.  相似文献   
10.
基于决策树分类的云南省迪庆地区景观类型研究   总被引:3,自引:0,他引:3  
李亚飞  刘高焕  黄翀 《资源科学》2011,33(2):328-334
决策树分类是基于空间数据挖掘和知识发现的监督分类方法。本研究利用遥感TM数据和DEM数据,构建分类决策树,并通过ENVI软件实现决策树分类,得到迪庆地区的景观类型分布图。同时利用传统的监督分类的方法进行分类,得到该地区景观类型分布图。利用野外实地采样的数据对两种分类方法进行精度评价,结果表明,两种分类方法的总体分类精度分别为85.5%和67.4%,决策树分类方法的总体分类精度比传统监督分类提高了近20%。在此基础上,研究云南省迪庆地区的景观类型分布状况,可得到以下结论:迪庆地区的景观类型主要有河谷灌丛面积约占5.5%,针叶林面积约占36.16%,亚高山灌丛草甸面积约占3.4%,高山冰雪面积约占3.7%,裸地面积约占25.4%,水体面积约占4.4%。除裸地和水体外,其他景观基本都沿着山体按海拔高度和坡向分布,其中面积最大的为针叶林景观。这与该地区高山峡谷地貌吻合。  相似文献   
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