湖南湘江流域城镇体系空间结构特征及优化

湘江流域是湖南省经济发展条件最好、经济发展水平最高、生产要素最密集的地区，是连接珠江三角洲开放区和长江沿岸开放带的纽带，其空间结构不仅直接影响湖南省的产业空间布局，而且对整个南中国地区的区域经济空间格局的形成和演化有重要影响．湘江流域分布有6个地级市、9个县级市和534个建制镇，其城镇体系空间结构处于极化阶段，点轴走廊式空间结构特征明显．城镇密度较大，但分布不均匀，存在着明显的轴线特征和核心边缘结构．为了实现湘江流域城镇体系空间结构的整体优化，应采取点轴式空间开发模式，使水系成为区域联系开放性通道，并加强不同等级的城镇建设，构建“一区三圈四轴”的开放性城镇体系空间结构．

Study on the Characteristics and Optimization Strategy of the Spatial Structure of Urban System in the Xiang River Reaches Hunan

The Xiang River reaches, which has the best conditions for economic development, is a district with the highest level of economic development and the most intensive productivity elements in Hunan Province. The region is the corridor which links the Pearl River Delta Region and Yangtze Basin Region. The spatial structure of urban system in this region has been undergoing constant evolution and development and it not only directly affects the spatial distribution of industries, but also it has a major impact on the formation and evolution of regional economic spatial pattern in entire South China Xiang River reaches, which now has 6 cities at prefecture level, 9 cities at country level and 534 designated towns, it has formed a spatial structure with cores and axis.The spatial structure of urban system in Xiang River reaches with higher urban density but uneven spatial distribution is at the polarization phase and it has obvious characteristics of axis distribution and core-periphery. In order to optimize the spatial structure of urban system in Xiang River reaches, the point-axis spatial development model is advisable,which makes the river system as an open corridor for the regional economic connection, at the same time, the urban system consisting of diffrent levels of central cities and should be constructed and a open urban system consisting of ＂one core, three spheres, four axis ＂should be formed.