地形影响下的贵阳城市避灾绿地可达性研究

Study on the Accessibility of Disaster Avoidance Green Space in Guiyang Under the Influence of Topography

避灾绿地可达性可以间接反映城市地形特征及布局。用实地勘察、文献检索等方法,对贵阳市自然环境、绿地建设情况进行调查;借助ArcGIS软件平台对贵阳市地形及居住点、绿地分布、服务范围及可达性进行研究,分析地形对绿地避灾可达性和有效避灾面积的影响。通过对贵阳市17个城市绿地的研究发现:1)基于1998—2018年遥感影像分析,发现贵阳市1998—2018年期间城市绿地呈现减少趋势,累积减少136.61 km2;2)对避灾可达性的影响:公园可达性在5 min内能够到达的只占总可达面积的1.65%;10 min可达占比4.36%;20 min可达范围占比13.18%;60 min占比63.67%。3)黔灵山公园等6个公园的有效避灾面积占比不足1%,观山湖公园等8个公园的有效避灾面积占比不足10%。同时还发现:城市广场占比较高,但数量较少,难以满足贵阳市总人口的避灾需求。

The accessibility of disaster avoidance green space is an important factor that indirectly reflects the urban topographical characteristics and layout.Use the methods such as field survey and document retrieval to investigate the natural environment and green space construction of Guiyang;use the platform of ArcGIS software to study the topography and residential areas,green space distribution,service range and accessibility of Guiyang,and analyze the impact of topography of green space disaster prevention and accessibility of effective disaster avoidance area.Through the 17 urban parks from Guiyang,it is found that:1)Based on the analysis of remote sensing images from 1998 to 2018,it was found that the urban green space in Guiyang showed a decreasing trend from 1998 to 2018,with a cumulative decrease of 136.61 square kilometers;2)Impact on disaster avoidance accessibility:Park accessibility can only account for 1.65%of the total reachable area within 5 minutes;10 minutes can account for 4.36%;20 minutes can reach 13.18%;60 minutes accounted for 63.67%.3)Six parks,including Qianlingshan Park,accounted for less than 1%of the effective disaster-avoided area,and 8 parks including Guanshanhu Park accounted for less than 10%.At the same time,it was also found that the urban squares account for a relatively high proportion,but the number is small,which is difficult to meet the disaster avoidance needs of the total city.