长三角城市土地扩张与人口增长耦合态势及其驱动机制

The coupling and driving forces between urban land expansion and population growth in Yangtze River Delta

长三角是中国城市土地快速变动和人口快速集聚的热点地区,厘清并协调城市土地扩张与人口增长间的关系,对统筹区域土地资源合理配置,调控人口流动及实现新型城镇化意义重大。以长三角16个城市为研究对象,采用重心耦合模型和基于人均约束性构建的协调性系数,对1994-2012年城市土地扩张与人口增长的总体耦合态势及演变、空间耦合特征及格局进行分析,并探讨影响城市土地扩张与人口增长耦合的驱动机制。结果表明:1长三角城市土地扩张速度整体快于人口增长速度,二者增长具有明显的阶段特征和显著的空间差异特征。2长三角城市土地扩张与人口增长耦合关系处于不断变化过程中,人地耦合关系整体上呈现出增强—减弱—增强的态势,土地重心与人口重心间的距离不断缩小,土地扩张与人口增长间协调性逐步增强;城市土地扩张与人口增长空间耦合类型中,人口过快增长型和人地基本协调型数量有所减少,但其在空间分布上呈现集中的趋势;土地快速扩张型的数量有所增加,在空间上呈现扩散的趋势,各城市人地配置协调程度不高。3经济发展、产业结构升级调整、交通发展与区位条件变化、政策因素等是影响长三角城市土地扩张与人口增长及其耦合变化的重要驱动因素。

The Yangtze River Delta is a hotspot with rapid change of urban land and population agglomeration. Understanding the coordination between urban land expansion and population growth will be of great significance to optimize the allocation of land resources, regulate population flow and facilitate the implementation of new urbanization. This study analyzes the relationship between urban land expansion and population growth in the Yangtze River Delta using gravity coupling models and coordination models. Our results show that：（1） The speed of land expansion is faster than the rate of population growth, which shows significant periodic and spatial difference;（2） The coupling between land expansion and population growth generally shows a tendency of＂first strengthened, then weakened and last strengthened＂from1994 to 2012, and the distance between the center of urban land gravity and population gravity was shortened, which indicates that the coordination between urban land and population growth was enhanced. The number of cities with rapid population growth has decreased, so does the coordination between land expansion and population growth, although cities of these two types show a spatial agglomeration tendency. Meanwhile, the number of cities with land expansion has increased significantly, and the distribution has showed a trend of expansion. The results demonstrate that there is no high level of coordination between land expansion and population growth.（3） Economic development, changes in industrial structure and zone bit, transportation development and government policy may have contributed to urban land expansion and population growth as well as to their coupling relationship.