汉水流域城市空间分布的分形研究及优化举措

流域空间结构研究是空间结构理论研究的深化，是基于具体区域类型的空间结构理论研究尝试。而流域城市空间结构是流域空间结构的重要组成部分。以汉水流域为例，对其城市规模结构、空间分布进行了研究，得出：城市体系比较完整，但城市首位度大，规模结构失衡；城市密度较大，空间分布很不均衡；城市分布的轴向特征明显。接着用差异度（表征城市等级规模的分形参数）和关联维数（刻画城市空间分布的分形参数）进行了验证，最后对优化城市群体结构提出了几点建议：强化武汉一级中心城市的龙头作用；构建襄（樊）十（堰）南（阳）成长三角；积极发展地方性中心城市；加快区域空间结构轴的建设。

A FRACTAL STUDY AND OPTIMIZATION ON SPATIAL DISTRIBUTION OF URBAN IN HANSHUI VALLEY

Valley spatial structure study is beneficial for the further development of spatial structure theories based on the concrete region type.Research on urban spatial structure is an important part of valley spatial structure.Taking Hanshui valley as an example,urban scale structure and spatial distribution are studied,and some conclusions are drawn: urban system is relatively perfect,but the urban primacy index is too big,scale distribution is lopsided;urban density is comparatively big,spatial distribution is seriously unbalanced;characteristics along axis direction of urban distribution is obvious. The important characteristics of urban spatial distribution is proved by using difference degree and correlation dimension.Some proposals are put forward for the optimization of urban system such as strengthening bibcock status of Wuhan as primary central urban;building growth triangle in Xiangfang-Shiyan-Nanyang; developing actively local level central urban and increasing the construction of regional spatial structure axis.