城市群空间结构效益评价与优化研究——以长株潭城市群与环洞庭湖城市群为例

从城市群规模效益、距离效益和空间联系效益3个方面出发,运用ArcGIS和城市相互作用强度模型对长株潭城市群和环洞庭湖城市群空间结构效益进行评价比较分析。结果表明：环洞庭湖城市群在外在规模上具有相对优势,具体表现为人口规模、空间规模以及城市数量较大,但城市群的紧凑度不高,城市规模等级结构优势不够明显,空间可达性较差,重要城市之间的空间联系不够紧密,呈现“大而散”的特征;相对而言,长株潭城市群城市数量、人口规模及用地较小,但其紧凑度及规模效益较高,城市规模等级结构优势度相对较高,可达性较好,重要城市之间的空间联系较为紧密。在此基础上,以实现城市群空间结构效益最大化为目标,构建了以长沙为中心城市的“一心两圈三轴”结构体系。

Comparison and Optimization of the Spatial Structure Benefits of Urban Agglomeration: A Case Study of Changsha-Zhuzhou-Xiangtan Urban Agglomeration and Dongting Lake Urban Agglomeration

Urban agglomeration is an important space carrier to promote new urbanization, and the spatial structure is the spatial reflection of the degree, stage and process of urban agglomeration. From the 3 aspects of urban agglomeration benefit, distance benefit and spatial connection benefit, this article use ArcGIS and urban interaction intensity model to compare the spatial structure benefits of the Changsha-Zhuzhou-Xiangtan urban agglomeration and Dongting Lake urban agglomeration in the development stage. The results show that Dongting Lake urban agglomeration has a comparative advantage in external scale including the population scale, land area and the city quantity. However, the compactness of urban agglomerations is low, the advantages of urban scale structure are not obvious enough and the spatial connection between important cities is not tight enough. It shows a more obvious "big and scattered" characteristics, and the quality of development and the degree of development are not good. Changsha-Zhuzhou-Xiangtan urban agglomeration is relatively small in terms of number of cities, population size and land use, but its compactness and scale benefits are relatively high, and the scale structure has a relatively high degree of dominance. On this basis, aiming at maximizing the efficiency of urban agglomeration spatial structure, the spatial structure system of “one heart, two circles and three axes” and “1+5” urban agglomeration with Changsha as the center city is proposed, which to provide references for the optimization and development of the urban agglomeration spatial structure.