杭州城市建设用地扩张的时空演变分析

基于杭州市1914—2018年间6期近代地图与遥感影像数据，通过目视解译数字化的近代地图，使用面向对象的分类方式对CORONA、Landsat TM和OLI影像进行分类并提取建设用地数据，计算扩张速度、重心变化、景观格局指数和增长类型，分析建设用地的扩张过程与扩张模式。结果表明：（1）近百年来杭州城市建设用地扩张明显，扩张过程主要集中在改革开放后。（2）杭州城市重心经历了“北—西北—北—东南—南”的变化过程，由向单一方向扩张转变为多方向均衡发展的态势。（3）建设用地扩张过程基本符合“扩散—融合”假说；城市核心区呈现蛙跳增长、填充增长、边缘增长依次主导的螺旋式发展过程，研究区域整体表现为边缘增长始终占相对重要地位的特征。（4）通过近代地图与遥感影像的集成分析，为长时间尺度的城市研究提供了一种路径。

Spatiotemporal changes of construction land expansion in Hangzhou city

This study is based on historical maps and remote sensing images of Hangzhou in 6 time periods from 1914 to 2018, construction land data is extracted through visually interpreting digital historical maps and classifying CORONA, Landsat TM and OLI images using object-oriented method. Construction land expansion process and expansion mode are investigated by calculating expansion speed, gravity change, landscape metrics and growth types. The results show that: (1) Hangzhou's construction land has been significantly expanded during the past hundred years, and the expansion process took place mainly after the beginning of reform and opening up. (2) Hangzhou's urban gravity has moved along the way of "north-northwest-north-southeast-south", from single direction expansion to balanced development in multiple direction. (3) Construction land expansion process basically conforms to the "diffusion-coalesce" hypothesis. A spiral process excessively dominated by leapfrogging, infilling and edge-expansion is shown in the urban core area, while the mode of edge-expansion always occupies a relatively significant role in the whole research area. (4) The integrated analysis based on historical maps and remote sensing images provides a feasible way for long-term urban research.