均衡和效率双重视角下武汉市主城区公园绿地空间布局优化研究

公园绿地是城市公共服务设施的重要组成部分,其空间布局与城市居民生活息息相关。根据布局现状,以2020年为优化时间结点,兼顾布局效率和布局均衡,首先以居民出行成本最小化为效率性目标,构建选址模型以对新增公园绿地进行选址;再以可达性差异最小化为均衡性目标,构建面积优化模型以确定公园绿地的合适规模。两种模型共同实现了公园绿地的布局优化。研究表明:(1)现状条件下,公园绿地布局不能满足居民的基本游憩需求,空间效率性和均衡性较低;(2)要实现本文的优化目标,需新增全市性公园绿地28座,共计1 100 hm2;需新增区域性公园绿地34座,共计868. 01 hm2;(3)区位选址模型显著降低了居民到达公园绿地的出行成本,人均出行成本由1 311. 24 m降低到了915. 93 m;(4)区位选址和规模优化模型能够显著提高公园绿地布局的均衡性,使得公园绿地布局与居民人口比配达到均衡,居民至整体公园绿地可达性差异系数由0. 71降低到了0. 54。

Study on the Spatial Distribution Optimization of Park Green Spaces in the Main City of Wuhan from the Perspective of Both Equilibrium and Efficiency

Park green space is an important part of urban public service facilities, whose spatial distribution is closely related to the life of urban residents. According to the status of the layout, this paper takes 2020 as the optimal time node and takes into account both the efficiency and the equilibrium of layout. First, this paper takes the minimization of residents travel cost as the efficiency goal, and constructs the location optimization model to locate the newly added park green spaces. Then we take the minimization of accessibility difference coefficient as the equilibrium goal, and construct the area optimization model to determine the appropriate scale of park green spaces. The two models have jointly realized the layout optimization of the park green spaces. The conclusions of this study show that: (1) Under the present conditions, the layout of the park green spaces cannot meet the basic recreation needs of the residents, and the spatial efficiency and equilibrium are quite low.(2) To achieve the goal of the optimization, we need to add 28 urban park green spaces（1 100 hectares）and 34 regional park green spaces（868.01 hectares）.(3)The location model can significantly reduce travel cost of the residents to park green spaces, and the per capita travel cost can be reduced from 1 311.24 to 915.93 m. (4) The location and area optimization model can significantly improve the equilibrium of park green spaces’ layout, making it balanced with the population of residents.The accessibility difference coefficient of the residents in different regions to the park green spaces has been reduced from 0.71 to 0.54.