以广州市城区为例,基于分形理论,借助GIS技术手段,测度广州市城区1957、1982和2008年交通网络的盒子维数。结果表明:①广州市城区路网具有明显的分形特征,不同区域的盒子维数均有不同程度的增加,城市路网覆盖度不断提高,道路密度和通达性不断增强;②根据不同时期不同行政区路网盒子维数的差异和增幅大小,把广州市城区路网发育划分为3种不同类型:成熟型(东山区、越秀区、荔湾区),发展型(黄埔区、芳村区、白云区),拓展型(海珠区、天河区);③建立不同区域盒子维数与年代的线性、指数和幂指数函数关系,经对比发现指数函数关系拟合度最好,其相关系数R2〉0.8,表明广州市城区交通网络近50年来发展迅速,而且这种态势还将持续下去。
With the Fractal Theory and GIS technology, this paper utilizes the box counting estimators to analyze the development characteristics of transport network in the urban areas of Guangzhou in the years 1957, 1982 and 2008. The result shows that: 1) Guangzhou transport network exhibits prominent fractal characteristics. The box counting estimators in different areas are all increasing, that manifests the improvement of coverage of urban road system and the enhancement of urban road density and accessibility; 2) The development stages of transport network system could be classified into 3 types: mature stage (Dongshan District, Yuexiu District, Liwan District), developing stage (Hangpu District, Fangcun District, Baiyun District) and expanding stage (Haizhu District, Tianhe District); 3) Urban rosd system in Gangzhou has developed rapidly in the past fifty years and this trend will continue in the near future. Comparison between linear, exponential and power-exponent development models of box counting estimators in different aeras indicates that exponential model achieves optimal fitting degree with a correlation coefficient of 0.8.