江苏省城镇间可达性及其格局演变研究

JIANGSU URBAN ACCESSIBILITY IN TERMS OF LAND TRANSPORT

可达性评价一般包括网络分析和栅格分析。借助ArcGIS的空间分析功能,采用栅格分析方法,以江苏省65个县(市)行政中心(城镇)为研究节点,利用1990、1996、2002和2008年的交通路网数据,对江苏省4个研究年度城镇间两两可达性进行了分析,探讨了其格局演变特征。结果表明:江苏省城镇间可达性改善明显;城镇间可达性结构由"纺缍型"向"倒金定塔型"转变;城镇间可达性总体差距在不断缩小,城镇间联系更加紧密;城镇间可达性改善并不均衡;交通建设的不均衡发展,导致城镇可达性和区位优势的改变。

The evaluations of accessibility generally include network analysis and raster analysis.With the spatial analysis function of ArcGIS and the VB programming language,by the method of grid analysis,to regard the 65 administrative center of counties or cities in Jiangsu Province as the nodes,under the help of traffic network data of Jiangsu Province in the year of 1990,1996,2002 and 2008,straight-line distance and accessibility data are extracted between each of the 65 cities in Jiangsu Province.Based on the accessibility data,the paper analyzed the accessibility of Jiangsu Province for four study years and discussed the evolution characteristics.The conclusions show： The accessibility between each of urban in Jiangsu Province is improved significantly,and the structure is evolved from ＂spindle type＂ to ＂down payments type＂,the gap of accessibility continued to narrow,the urban contact each other more strongly.Natural conditions and regional conditions are the factors of the accessibility＇s improvement.Differences in the development of transport infrastructure,lead to the changes of urban accessibility and regional advantages.