四个可持续发展实验区绿地系统可达性比较研究

我国可持续发展实验区所在城市均十分重视绿地系统对其可持续发展的重要支撑作用。布局合理的城市绿地系统不但能提高城市生态空间容量,也能充分满足不同位置城市居民的需求,这使得城市绿地与其被服务对象——城市居民之间的可达性成为评价城市绿地系统服务价值的重要指标。以高德公司生产的电子导航地图中居民区点和绿地系统数据为基础,采用GIS缓冲区分析法,分别探讨了我国4个有代表性的国家可持续发展实验区西城区、石景山区、绍兴市和日照市这4个城市的城市绿地系统斑块特征,以及5,5—15,15—30min时间距离内所覆盖城市居民点数量,对其绿地可达性及其服务能力进行比较分析和研究。研究结果表明:4个可持续发展实验区内的绿地系统分布均比较合理,覆盖面广,尤其是30min时间距离内可达的绿地满足了95%的住区;80%以上的住区居民可以在15min内到达周边任意绿地,为城市绿地管理部门打造"一刻钟生活圈"提供了良好的基础。但同时也发现,提供服务的绿地斑块面积比较细碎,大型绿地的配置率相对较低;而且多数绿地斑块从属于多个时间距离半径内,承受较大人口压力。最后,建议城市规划过程中,注重绿地系统与住区从时间尺度上的协调分析。此外,尝试性地采用日常生活中普遍使用的电子导航地图开展城市绿地系统可达性分析,研究结果与城市居民的生产生活密切相关,对城市绿地系统规划具有实际指导意义。

A comparative study of green system accessibility in four sustainable development experimental zones

Cities located in sustainable development experimental districts value the vital supporting role played by their corresponding green space systems. A rational layout of an urban green space system can increase the urban ecological space capacity and meet the various demands of populations in different locations. Citizens are an important indicator for evaluating the success of an urban green space system. This study used residential points and green space systems in electronic navigation maps produced by and the GIS buffer analysis method to analyze the patch characteristics of urban green space systems in the four representative national sustainable development experimental districts. These were-Xicheng district, Shijingshan district, Shaoxing City, and Rizhao City. In addition, a comparative analysis of the amount of people within different time distances from green spaces (< 5 min, 5-15 min, and 15-30 min) in urban residential districts was used to assess green space accessibility and service ability. The results showed that the distributions of the green space systems in the four sustainable development experimental districts were reasonable and that they were widely accessible, especially with regards to people who lived within 30 min of green space, which covered 95% of the local residents. More than 80% of the residents could reach any nearby green space within 15 min, which provided a good foundation on which the urban green space management department could build "a quarter of an hour life circle." However, at the same time, we found that the green spaces providing services were dispersed and small and that large green space areas were limited. Most of the green areas within the different time/distance radii were subject to higher population pressures. The results from this investigation suggest that urban planning processes should consider the time/distance factor for residents when planning a green space system. In addition, this study used electronic navigation maps, which are widely available, to analyze urban green space system accessibility. The results of this study are relevant to areas where urban residents were living and working, which will have practical significance when planning an urban green space system.