2000-2012年中国地级以上城市空间弹性分析

中国快速城镇化进程中土地城镇化与人口城镇化的不协调导致城市土地蔓延、集约程度低,研究城市土地的扩张速度和程度,并进行城市间的横向对比分析,对于城市增长边界划定、统筹城市空间规划具有重要意义。城市在发展过程中,城市用地面积、人口数量变化表现为城市人口密度随时间变化,一定程度上反映了城市土地的扩张程度和内部发展潜力,称之为城市空间弹性。以中国263个地级以上城市为样本,以2000-2012年间城市人口密度及其变化率为基础,采用位序评分法构建计算简便、横向可比的城市空间弹性指标。根据弹性计算结果将城市划分为高弹性、较高弹性、中等弹性、较低弹性和低弹性5个等级。中国东部地区高弹性城市占比较高、中部地区以较高弹性和中等弹性城市为主、西部地区城市弹性主要为中等以下水平。研究期内绝大多数样本城市人口密度降低,城市空间弹性增加,在2000-2006年间尤为明显。进一步结合中国五大城市群分析看出,总体上经济发达地区城市空间弹性较大,但是城市群中的核心城市弹性中等或较小。根据城市空间弹性计算结果可以更加合理确定城市增长边界划定的优先次序以及进行刚性和弹性边界的程度控制。

The spatial resilience of prefecture-level cities in China from 2000 to 2012

China is experiencing rapid urbanization and land urbanization and population urbanization have led to urban land sprawl and low-efficiency land use. Analysis of urban spatial resilience and regional differences is of significance for urban spatial planning in China. During urban development,changes in urban construction land area and population cause changes in urban population density over time,reflecting change in urban spatial resilience. We selected 263 cities at the prefecture level and above,and used total population at the year-end and urban construction land area to calculate population density,to calculate the rate of change in density using indicators rank scoring methods to determine urban spatial resilience indicators. We found that all cities can be divided into higher spatial resilience,high spatial resilience,medium spatial resilience,less spatial resilience and low spatial resilience using the natural breaks classification method. Urban spatial resilience decreases from east to west and the highest proportion of higher spatial resilience cities are in eastern China. In central China,high and medium spatial resilience cities are found at a higher proportion. In western China,cities of medium and lower spatial resilience are more common. Along with the urban development,China’s urban population density reduced but urban spatial resilience increased,particularly 2000 to 2006. From the five urban agglomerations in China it is clear that economically developed areas have higher spatial resilience,but the cores of urban agglomerations have medium or low spatial resilience. The application of urban spatial resilience analysis can assist in the design and definition of urban growth boundaries in China.