基于雷达卫星图像的黄淮海平原城镇体系空间结构研究

基于雷达卫星ScanSAR遥感图像分析 ,根据中心地理论 ,对黄淮海平原不同地貌、水文等要素影响下的城镇体系空间结构进行研究。结果表明 :1)利用雷达遥感对结构信息的灵敏反应和雷达卫星ScanSAR合适分辨率 ,在图像上直接显示出建成区的分布和范围 ,直观反映出城镇相对等级 ,这也表明雷达遥感在城市地理研究中的应用潜力 ;2 )黄淮海平原城镇空间结构深受自然条件特别是地貌尤其是水文 (河流、古河道、湖泊 )的影响 ,城镇体系可划分为 5种类型区 ;3)发展了河流影响下的中心地体系由六边形向五边形或四边形演化的构建模型 ;4)无论六边形还是五边形的中心地体系 ,本区体现了理论上对中心地间的距离构建法则与实际情况的良好关系 ,实证了克氏的中心地理论在黄淮海平原重要农产区的某种存在。

On Spatial Structwre of Urban System of Huang-Huai-Hai Plain Based on Radarsat Mosaic Image

Differ from optical remote sensing, Radar remote sensing has theability of imaging all-time, all-weather and penetration to cloud and dry sand and soil. Besides penetration, Radar can also detect micro-relief, building , vegetation distribution, surface roughness and water content sensitively, thus is superior to other remote sensing means for these studies. It has become one of the most important techniques for earth observation. Canadian Radarsat was launched in 1996, and is the first commercial operating SAR system. It has seven kinds of beam mode and twenty-five imaging modes, of which ScanSAR mode can obtain images with swath of 300 km (Narrow) and 500 km (Wide), and resolution of 50m and 100m. It conforms to analyses of regional urban geography. Based on central place theory, the spatial sturctre of Hrban system of Huang-Huai-Hai Plain is studied by using Radarsat ScanSAR narrow mode mosaic image.spatial structre of The results are: 1) Radarsat ScanSAR data are suitable for automatic extraction of building-up area and has meaningful potential for urban geographic study. 2) The urban system of Huang-huai-hai plain, which is deeply influenced by physical factors, especially hydrographic factors( such as river, paleochannel and lake), can be divided into five categories.They are: urban system of equal distance between central places on fluvial fan region by Mt. Taihangshan; hexagonal urban system in central part of Hebei plain; pentagonal urban system in Huanghe River fluvial fan; quadrilateral urban system in the vicinity of Huaihe River system; and scattered new towns in the places of rolling hills in central and southern in Shandong Province. 3) A evolution model of central place system from hexagon to pentagon and to quadrangle governed by river is suggested. 4) No matter hexagonal or pentagonal urban systems, this study has demonstrated that there are good relationship between the model of distance structure of central place and the real -life instance.