摘要
通过利用分形理论计算出昌九地区137个城镇城市首位指数,测算出城镇规模级别分布维数、聚集维数、网格维数,从而揭示昌九地区城镇体系的空间分布状况。研究表明:1)利用城区常住人口规模测算出两、四城市指数,分别为3.56、2.36,均高于正常值,表明昌九地区城镇体系属于首位型分布;从城镇体系规模级别测算出分维数为0.758 8,验证了昌九地区城镇体系呈极核型结构,城镇规模分布不均衡;2)南昌市区、九江市区的集聚维数为0.755 9、0.614 4,中心城区在昌九地区城镇体系自组织演化过程中核心作用显著;3)昌九地区城镇分布的容量维与信息维分别为1.754 5、1.510 6,城镇分布均衡性偏低,城镇稀疏的地区分形形态不佳。昌九地区城镇体系结构呈现不平衡状态,首位城市的垄断性较强,小城镇发育不完全,影响了城镇体系功能的充分发挥,提升中小城镇功能是今后昌九地区今后城镇体系的主要发展方向。
In order to study the spatial distribution of urban system in Nanchang-Jiujiang area, fractal model has been applied to calculate the urban primacy index of 137 towns in this area, then meas- ured the distribution fractal dimension of town scale, aggregation dimension and grid dimension. The result shows that the urban system of this area appears to be the first-place distribution, and the Two and Four city indexes were higher than normal （ Two and Four cities indexes were 3.56 and 2.36）, which is calculated from the urban resident population. The fractal dimension calculated from the scale level of the urban system was 0. 758 8 ,which verified the urban system of study area was Polar karyotype structure with an unbalanced urban size. Nanchang and Jiujiang played central roles during the urban system self-organizing evolution （the aggregation dimensions were 0. 755 9 and 0. 614 4）. The uniformity of town distribution in study area is relatively low, and the fractal shape of sparse area is unsatisfactory （conducted by capacity dimension 1. 754 5 and information dimension 1. 510 6）.Due to the unbalanced urban system structure, the strong monopolization of primate city and the un- complete development of small towns, the function of urban system in study area can not be fully played. Therefore, enhancing the function of small and medium cities will be helpful to the develop- ment of the Nanchang-Jiujiang area＇s urban system.
出处
《江西科学》
2017年第1期171-179,共9页
Jiangxi Science
基金
江西省数字国土重点实验室开放基金(DLLJ201611)
关键词
分形理论
城镇体系
空间结构
昌九地区
fractal theory
urban system
spatial structure
Nanchang-Jiujiang area
