基于多源数据的长沙市半城市化地区识别与演变研究

Research on the Identification and Evolution of Semi-Urbanized Areas in Changsha City Based on Multi-Source Data

摘要: 半城市化地区是城乡职能混杂交织、城乡景观相互渗透的复杂地域结构，科学识别该类地区并探索其发展规律是优化国土空间格局、推进城乡融合发展的关键。在多源数据支持下，本文以中部特大城市长沙市为研究区，从社会经济、利用类型、景观特征、集聚水平四个特征切入，运用Densi-Graph核密度估计法、信息熵及G-统计量综合量化2010、2015、2020、2023年长沙市半城市化空间范围，分析其时空演变规律。研究结果表明：(1) 长沙市半城市化区域在不同年份展现出相似的分布模式，均呈现出以核心区为中心的圈层式分布格局；(2) 长沙县、望城区存在大量半城市化地区，其面积远高于其他区域，芙蓉区已实现完全城市化；(3) 长沙市的半城市化地区在2010~2023年呈现逐渐减少的趋势，半城市化地区以内圈收缩为主，并伴有少量的外圈扩张，表明长沙市城镇化发展趋于有序，乡村工业化及城市无序蔓延明显放缓。

Abstract: Semi-urbanized areas are complex regional structures with intermingled urban and rural functions and interpenetrating urban and rural landscapes, and the key to optimizing the spatial pattern of land and promoting the integrated development of urban and rural areas is to scientifically identify such areas and explore their development rules. With the support of multi-source data, this paper takes Changsha, a megacity in central China, as the study area, and analyzes its spatiotemporal evolution law by using the Densi-Graph kernel density estimation method, information entropy and G-statistic to comprehensively quantify the spatial scope of semi-urbanization in Changsha in 2010, 2015, 2020 and 2023 from the four characteristics of socio-economy, utilization type, landscape characteristics and agglomeration level. The results show that: (1) The semi-urbanized areas of Changsha show similar distribution patterns in different years, and all of them show a circle-like distribution pattern centered on the core area; (2) there are a large number of semi-urbanized areas in Changsha County and Wangcheng District, which are much higher than other areas, and Furong District has been fully urbanized. (3) The semi-urbanized areas of Changsha show a gradual decreasing trend from 2010 to 2023, and the semi-urbanized areas are mainly shrinking in the inner circle, accompanied by a small amount of expansion in the outer ring, indicating that the urbanization development of Changsha tends to be orderly, and the rural industrialization and urban disorderly sprawl have slowed down significantly.