中文摘要：

基于长江经济带1988、2001、2012年路网数据,在Arc GIS软件支持下,以长江经济带110个地级以上城市为基本研究单元,平均可达性为测度指标,对长江经济带城市及城市间可达性进行测算,探讨其格局演变特征。结果表明：（1）长江经济带区域整体可达性改善明显,但东部地区可达性水平优于西部地区的现象未得到有效改善;（2）区域内任一栅格到达最近城市所需时间逐步缩短,1 h圈空间格局由散点分布逐步向网络分布转变;（3）可达性改善状况区域差异显著,西部地区改善值远高于中部地区,平均可达性值越大其改善值越大;（4）城市间可达性水平得到显著提升,可达性水平主导频率由1988年的12-36 h逐步转向2012年的3-12 h,城市间可达性结构改变显著。

英文摘要：

Based on the road network data of the Yangtze Economic Zone in 1988, 2001 and 2012, we mainly probed into the cities in the zone as well as the accessibilities between them, and analyzed about the pattern evolution features of those cities＇ accessibilities. Using the Arc GIS software, we studied 110 prefecture-level cities（the basic research unit in the Economic Zone）, and took the average accessibility as the measurement index. The results are briefly shown as follows.Firstly, the accessibilities in the Yangtze Economic Zone had a significant improvement, while with huge regional disparity, the accessibilities in the eastern part were still far higher than the west part. Secondly, the time required to the nearest city was gradually reduced, the spatial pattern ＂one-hour circle＂ was progressively transformed from a ＂dot＂ to a＂net＂ structure. Thirdly, the regional difference of accessibility improvement was significant, and the improvement of the western region was much higher than that in the central region. The greater the accessibility value, the greater the degree of improvement is. Fourthly, the inter-city accessibility was enhanced greatly. The dominant frequency of the accessibility changed from 12-36 hours in 1988 to 3-12 hours in 2012 step by step, and the accessibility structure of cities changed significantly.