成都市避震疏散公园绿地面积指标

An analysis on area of park and open land for evacuation and refuge during earthquake in Chengdu

城市公园绿地作为城市生态系统的重要组成部分,在避震疏散中发挥了重要作用。以5.12汶川大地震灾害对成都市中心城的影响为例,通过计算地震后避难人数和避震疏散所需公园绿地面积,从而探讨研究区现有公园绿地面积是否满足避震疏散需求。研究结果显示,成都市中心城区在5.12汶川大地震中长期避难人数为30.92万人,所需紧急、固定避震疏散场所总面积分别为441.82hm2、77.31hm2,所需紧急、固定避震疏散公园绿地面积分别为300.85hm2、46.26hm2。研究区现有不同规模的公园绿地表现出景观分布格局差异。除高新区和武侯区外,其余4个区的公园绿地面积均不能满足紧急避震疏散需求,而6个区可作为固定避震疏散公园绿地的面积均能满足长期避震需求。研究结果体现了避震疏散公园绿地面积指标体系的可行性和合理性,以此作为城市建设和公园绿地规划的参考,在提高城市绿地率的同时也满足避震疏散需求。

As a vital component of urban ecosystem, urban park and open land plays an important role in evacuation and refuge during earthquake. Aiming to understand whether the existing parks and open lands can meet the demand of seismic refuges for evacuation, this paper taking the impacts of 5.12 Wenchuan Earthquake on the central zone of Chengdu City as an example, analyzed the population of refuge and the area of park and open land needed for evacuation and refuge during earthquake. The results showed that, the total population of long-term refuge suffered from 5.12 Wenehuan Earthquake was 309.2 thousands. The total area of urgent and permanent seismic refuges for evacuation is 441. 82 hm^2 and 77. 31 hm^2 respectively. The area of urban park and open land available for urgent and permanent seismic refuges for evacuation 300. 85 hm^2 and 46. 26 hm^2, respectively, and they are spatially unhomogeneous distributed. Except Gaoxin and Wuhou districts, the urban park open area in other four districts could not meet the demand of evacuation and refuge during earthquake. Whereas, the area for permanent refuge in six districts could all meet the demand of refuge after earthquake. In a summary, the results infer that it is feasible and rationale to use the area of urban park and open land as an indicator for assessing land available for evacuation and refuge during earthquake. This provided an indicator for urban construction and park planning, and it could not only enhance the greening ratio, but also meet the demand of seismic refuges for evacuation.