摘要
针对城市用地无序扩张,城镇结构不合理等问题,在生态文明建设背景下,国家和地方政府提出划定城市边界管控城市扩张。该文综合白天光学遥感和夜光数据各自的优势,提出一种快速、精确的城市边界提取方法。一方面解决白天光学遥感数据提取城市边界的不连续问题,另一方面提高了基于夜光数据提取城市边界的精度。通过构建VANUI夜光指数,建立同心圈模型搜索方式,结合图像的空间差异确定粗略的城市范围,进而建立缓冲区,最后利用改进的边缘检测算法得到城市边界。研究表明,该文提出的方法获得了较好的精度。基于上述提取方法,以杭州为例,通过扩展强度指数、等扇分区法分析城市边界的时空动态变化。结果表明,研究期内杭州城市区域面积快速增长,其中2000—2012年城市区域面积年均增长率超过2012—2018的年均增长率。整个研究期间杭州主要扩张方向为正东、东北和正北方向。
In response to the problems such as disorderly expansion of urban land and unreasonable urban structure,under the background of ecological civilization construction,the central and local governments proposed the urban boundaries(UBs)to control urban expansion.Combining the advantages of both NTL data and traditional optical RS data,a fast and effective method for extracting UBs was proposed.This method not only solved the discontinuity of the UB extracted from the traditional optical RS data,but also enhanced the accuracy of UB extracted from the NTL data.The VANUI index were firstly constructed,and then based on the proposed concentric zones model(CZM)and the variance-based method,the rough urban extent was identified.The modified Canny edge detection method was adopted to obtain the UBs based on the buffer zones.UBs extracted by the proposed method achieved a good accuracy.Taking Hangzhou as an example,the temporal and spatial dynamic changes of the UBs were analyzed through expansion intensity index and spatial direction analysis based on the method above.The result indicated that the extent of urban area in Hangzhou increased rapidly during this period,the average annual growth rate of the urban area from 2000 to 2012 were more than that from 2012 to 2018.The main expansion directions are east,northeast and north.
作者
袁于评
花益平
薛星宇
王珂
YUAN Yuping;HUA Yiping;XUE Xingyu;WANG Ke(Zhejiang Academy of Surveying and Mapping Science and Technology,Hangzhou 311100,China;College of Environmental and Resource Sciences,Zhejiang University,Hangzhou 310058,China)
出处
《测绘科学》
CSCD
北大核心
2022年第2期110-116,共7页
Science of Surveying and Mapping
关键词
夜光数据
同心圈模型
城市边界
动态变化
nighttime light data
concentric zones model
urban boundaries
dynamic changes
