轨道交通建设对金华城镇可达性格局的影响

The impact of rail transit construction on the spatial pattern of city accessibility in Jinhua

为了定量分析轨道交通建设对金华城镇可达性的影响,首先基于金华市公路路网结构和最短时间路径选择算法,运用Arc GIS 9.3软件对轨道交通建设前后的城镇可达性进行了对比分析.结果表明:金华各城镇的整体可达性较好,其中87%以上的区域可达性在1 h以内,并随着轨道交通建设而均得到不同程度的优化;可达性分散图在地域分布上呈现以城镇为中心的圈层分布结构;可达性较好的区域主要分布在"兰溪—金华市区—武义—永康"和"浦江—义乌—东阳—磐安"这2条轴线上,而2条轴线间城镇横向间的区域可达性较差,而且并未随着轨道交通的建设而得到明显改善;此外,因轨道交通线未贯穿磐安县,因而无论其县域内还是与其他县市间区域的可达性几乎没有发生变化.最后在上述分析的基础上,提出相应的优化措施.

In order to make a quantitative study about the impact of rail transit construction on the spatial pattern of city accessibility in Jinhua,it was firstly used the software Arc GIS 9. 3 to carry out an empirical research about the accessibility of city in Jinhua based on the highway network structure and calculations of optimal road routes and time to city of Jinhua. With the generated accessibility diffusion graph before and after the rail transit construction of Jinhua,a comparison and analysis of the graph and chart was made and analyzed. The result showed that the overall accessibility of cities was fairly good before the rail transit construction in Jinhua,and currently the accessibility time of 87% of Jinhua area was within 1 h. The accessibility of all the cities of Jinhua would be optimized on different levels as rail transit would be constructed. However,as to the regional distribution,the accessibility diffusion graph took on a laver structure taken cities as the center. The regions of better accessibility was showed to be distributed in two axes,specifically including″Lanxi-Jinhua City-Wuyi-Yongkang″ and ″ Pujiang-Yiwu-Dongyang-Pan′ an″. Despite all of this,the regions of worse accessibility were distributed in a zone between the two axes,and the accessibility of all the cities in Jin-hua was not going to be markedly improved as rail transit been constructed. Because rail transit lines in Jinhua would not run through Pan′an,the accessibility of the county region and the region between Pan′an and any other city had almost no change. On the basis of foregoing analysis,some corresponding optimization measures were suggested.