基于Voronoi图的新疆塔里木盆地城镇影响范围分析

确定塔里木盆地城镇影响范围,是新疆城镇体系规划、城市经济区划的一项基本工作,具有现实意义.建立城镇综合实力指标体系,运用Voronoi图在空间分割和地图制图应用中的诸多特性,提供一种新的城镇空间影响范围的划分方法,来实现对塔里木盆地城镇空间影响范围的生成和界定.结果表明:综合实力指数较高的城镇的影响范围一般会超过其所在市县的行政范围,较低的则小于其行政范围;盆地北部、西北部城镇密度较大的区域,城镇的辐射半径较小,影响范围绝对面积不大,南部、东南部城镇密度较小的区域,城镇的辐射半径大,影响范围绝对面积较大.此外,塔里木盆地南部县域的中心城镇的辐射范围呈现为竖向的条块状,并与其行政区划基本吻合,反映出塔里木盆地南部绿洲经济相对的独立性和完整性.

Influenced area of towns in Tarim Basin based on Voronoi diagram

The towns of Tarim Basin have grown by oases around the Tarim Basin brim in Xinjiang as a strain of bead. The development of those towns is a miniature of the evolution of tradition cities system in Xinjiang. In the Tarim Basin, the urbanization level is low, the speed of urbanization advancement is slow, and the types of urbani-zation regions are different obviously. Simultaneously the economy of the towns characters the oasis economy. The function of the towns is homologous strongly. The delimitation of influenced area of towns in Tarim Basin is an im-portant content of urban system planning and also the important aspect of urban science building of Xinjiang, which has practical sense. The paper built the system of indices of urban general strength, calculated and compared syn-thetic strength of the 42 towns in Tarim Basin through principle component analysis by setting up a series of inde-xes, including 13 indexes. On the analysis, by normalizing the indexes with Statistical Software SPSS13.0, rota-ting them by the method of varimax, analyzing the component matrix, five components were draw. And then, by multiplying each component score and corresponding component proportion, summing the consequences, the syn-thetic power of the towns was calculated. From high to slow, they are Korla, Aksu, Kuqa, Kashgar, Luntai, Ho-tan, Artux and so on. Analyzing as a whole, the paper takes Korla as the start point of urban general power, and then descend it gradually along counter-clockwise. Considering geometric particularity of Voronoi diagram, the ra-tionality for dividing up space and the solvability by computer, the paper tried to apply it in the studying of delimi-tation of influenced area, and gave an analytic demonstration taking the towns in Tarim Basin of Xinjiang as an ex-ample. Some conclusions have been obtained as follows: (1) The urban influenced area of the towns which have a higher integrative strength index, usually covers a wider area than its actual administrative region, on the contrary, the urban influenced area of the towns which have a lower integrative strength index, covers a smaller area than its actual administrative region. (2) The north and the north-west districts of Tarim Basin with a bigger city density have a smaller urban influence radius, and the absolute urban influenced area is not so wide. Situation of the south and the south-east districts of Tarim Basin go to the opposite. (3) Further more, the radiate range of the towns in the south of Tarim Basin presents as a vertical-bar shape. This is inosculated to the administrative region of this dis-trict. And it shows the relative independency and integrality of the southern Tarim Basin's oasis economy.