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The Chinese "Yangtze" alligator is a rare reptile that has been listed as an "endangered species" by the United Nations, so its preservation has become an urgent task. A study of its habitats through analysis of their Landsat images will provide a scientific basis for the government departments concerned to select the best locations for its breeding.The'Chinese alligator is a subtropical reptile of freshwater rivers, lakes and ponds. Found only in China, it is now distributed only in the border region between the three provinces of Anhui, Zhejiang and Jiangsu. On the basis of previous investigations by Chinese scientists, and from an analysis and interpretation of their Landsat images, we made a special study, review, and classification of the natural environment of the alligator's present habitats (and the modern changes in the natural background of these hatitats) so that the government departments concerned with the preservation of the reptiles may have a scientific basis for determining the best loc 相似文献
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黄津海平原上的河流、湖泊和海岸线,千百年来发生着巨大的变化。研究这些变化的规律,对该地区的水资源开发,国土规划和工农业生产有着重要意义。利用多时相的多种遥感资料,结合光学与计算机匹配和增强分析,可以比常规调查方法更快,更准确地识别出水域演变的“痕迹”,与历史记录资料进行对比,可以恢复古代水域的演变特征。对于水域短期内变化的定量监测,遥感技术更具有明显的优越性。通过多时期遥感资料分析,黄河三角洲自1855年以来,平均造陆率为23.7平方公里/年;白洋淀的水面从1961—1985年减少了426.6平方公里。通过遥感资料系统分析黄准海平原水域的变化表明,本区河流的改道频率在人工控制下越来越小;湖泊的水面逐年减少;海岸线在河口地区继续向海淤进。在整个水域变化过程中,历史时期,黄河的演变影响着其它水域的变化;而近代以来,人类的活动对水域的演变起着越来越大的作用。如白洋淀近年的干淀就与工农业用水增加、大量围垦等人类的主要活动有关。 相似文献
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黑白象片一般不能反映自然彩色，只能通过密度的差异反映被摄目标的形状和明暗程度。由于人们的眼睛对黑白影象的分辨能力是有限的，据实验证明，肉眼对彩色信息的分辨力较对黑白信息的分辨力高100倍。我们曾应用黑白航摄负片，分层浮雕染色合成假彩色图象，初步试验表明，运用此种方法将普通黑白片变成假彩色图象，能增强图象的分辨力，扩大黑白片使用范围。 相似文献
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近十年来,我国在卫星影象地图的编制研究工作上取得了显著成绩。我们在总结了以往编制经验的基础上,以快速、实用、节省为宗旨,采用光学合成镶嵌方法,先后编制了海南岛、京津唐地区、宁夏、辽宁、黄淮海平原地区等不同区域的假彩色卫星影象图。图版IV为黄淮海平原地区的假彩色卫星影象图。在编制工作中我们采用传统工艺和新技术相结合的方法,对卫星象片的平面位置误差进行了平均配赋和控制,同时对合成颜色进行协调处理,取得了良好的制图效果。基本上满足了区域环境及其动态变化研究的需要。本文谨就编制工作的几个技术问题,作一些初步探讨。 相似文献
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Study results on changes of rivers, lakes and coastlines have great significance for water resource exploitation, land use planning, industry, and agriculture.Recognition of traces of changed water areas can be done more quickly and correctly by processing multi-time and multi-type remote sensing data and image matching and enhancement with computer and optical equipments than by using conventional methods.Features of water area changes in ancient times can be recoverd by comparing Landsat data and air-photos with historical records.Remote sensing technique is very efficient for monitoring short-term quantitative changes of water areas.Systematic analysis of the remote sensing data of this region shows that river changes have become less frequent, that the area of lakes has decreased year by year, and that the coast line at the river mouth has continually moved seaward. Huanghe river activity caused changes of water areas here in ancient times. But human activities have been playing an increasingly impo 相似文献
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本文对编制“新疆维吾尔自治区卫星影像图”的方案设计、卫星资料的选择、MSS底片的处理,彩色合成和银嵌整饰等技术方法作了全面介绍.并利用影像图上丰富的干旱区地理信息、农林牧业分布、水系变迁,地图修饰等领域进行了应用性的初步分析。 相似文献
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