川滇地区城市地震风险变化分析

Analysis of Urban Earthquake Risks Changes in Sichuan-Yunnan Region

为了研究川滇地区城市地震风险变化,通过分析土地利用数据提取研究区城镇建设用地的变化,并采用以景观指数为基础的城市空间分布变化特征分析方法,获取川滇地区2000~2010年城市空间分布变化特征。再结合研究区地震动峰值加速度数据,采用地震风险时空变化识别方法,分别计算川滇地区2000年与2010年地震风险指数,并以区县为单位统计地震风险变化指数及变化率。结果表明:城镇呈现出离散型增长的地区,地震风险变化指数增长越明显;相较于其他地形,山地对地震风险变化指数的影响更大;相比于未发生过地震的地区,遭受过严重地震的地区的地震风险变化指数降低更明显。本次研究对川滇地区的防灾减灾工作有一定的参考价值。

In order to study the changes of urban seismic risk in Sichuan-Yunnan region,firstly,the change of urban construction land in the study area was extracted by analyzing land use data,and the change characteristics of urban spatial distribution in Sichuan and Yunnan region from 2000 to 2010 were obtained by using the analysis method of urban spatial distribution change characteristics based on landscape index.Secondly,combined with the seismic peak acceleration data of the study area,the seismic risk index of Sichuan Yunnan region in 2000 and 2010 were calculated by using the method of temporal and spatial change identification of seismic risk,and the seismic risk change index and change rate were calculated by taking districts and counties as a unit.The results show that in areas where cities and towns show discrete growth,the increase of earthquake risk change index is more obvious.And compared with other terrains,mountainous areas have a greater impact on earthquake risk change index.Moreover,the decrease in the index of seismic risk is more pronounced in areas that have experienced severe earthquakes than in areas that have not experienced earthquakes.