摘要
地震堰塞湖的破坏性不亚于地震灾害的直接破坏,开展堰塞湖的危险性评估,对灾后重建具有重要的参考意义。利用高分辨率遥感数据,结合辅助数据,确定了汶川灾区52处主要堰塞湖的名称、空间位置,识别出其鲜明的线状空间分布特征。堰塞湖的危险性评价,分为极度危险(1个)、高度危险(5个)和危险(46个)3个等级。遵循溃坝威胁区确定原则和方法,对堰塞湖溃坝威胁区进行了分析和划分,结果表明,重灾区受堰塞湖溃坝威胁的总面积为963.27km2,涉及18个县市(区)的134个乡镇。最后,对汶川地震重灾区的重建规划和堰塞湖风险规避提出了初步的建议。
Wenchuan Earthquake has seriously caused many huge landslides in the rivers in Si Chuan Province.As a result,huge water volume was blocked in the rivers and numerous dammed lakes appeared in the following days,which may result in inundation on the lake area and flooding disaster in the lower reaches.Therefore,it is urgent to reconnoitre the exsited dammed lakes and its spatial distribution,to monitor the stability of these dams and to evaluate the potential inundation area when the dam-break events occur.Incorporating the basic information of dammed lakes provided by other ministries,high resolution remote sensing imageries(including Spaceborne,Airborne and Unmanned Aerial Vehicle) from May,12 to June,12 2008,were used to confine the spatial distribution and to reconnoitre these dammed lakes.Based on the 'Atlas of Sichuan Province in 2001',combining with 'Sichuan Electronic Map in 2008' and '1∶50000 topographic map'as well,most of the dammed lakes were named from the nearest village at the same riverside,while other dammed lakes located deeply in the mountains with scarce villages were named from a nearer village,with serial numbers.Up to June 12,2008,we have identified total 52 dammed lakes in the heavily-affected area of'Wenchuan Earthquake'.The spatial distribution with high precision longitude and latitude of the dammed lakes,indicates a significant linear feature,which is consistent with earthquake faults.The risk evaluation of the dammed lakes in the heavily-affected area of 'Wenchuan Earthquake',was carried out mainly by using the monitoring results of high resolution remote sensing datasets and the authoritatively published results.According to the scale,the composition of the dams,the size and water storage capacity of these lakes,the distribution of the downstream cities and towns,population status and economic development levels,the possible affected area and the potential impact,the risk of the dammed lakes were divided into three levels: Extremely Dangerous,High Dangerous and Dangerous.Of the 52 dammed lakes,Tangjiashan is the only one in the Extremely Dangerous level,while the XiaoJiaqiao,Laoyingyan,Shiban'gou,Tangjiaba(Nanba),Changtan(Xiaogangjian) are 5 dammed lakes in the High Dangerous level,and the rest 46 dammed lakes are in Dangerous level. Principles for determining the potential flooded area when dam-break occurs were developed: 1.the safety,is taken as the most important objective;2.the inundation area should be determined in accordance with sufficient and reliable monitoring results and basic datasets;3.the region should not be over-extended.Further,we also developed the methods for confining the potential inundation area,by which the total acerage of the potential inundation area determined amount to 963.27 square kilometers,involving the 134 townships of 18 counties(districts).At last,preliminary suggestions were proposed to avoid risks of the secondary disasters of dammed lakes in the reconstruction planning for heavily-affected area in 'Wenchuan Earthquake'.
出处
《遥感学报》
EI
CSCD
北大核心
2008年第6期900-907,共8页
NATIONAL REMOTE SENSING BULLETIN
基金
中国科学院知识创新重要方向性项目“国家汶川地震灾后重建规划编制--资源环境承载能力评价”的支持
关键词
汶川地震
堰塞湖
遥感分析
危险性评价
Wenchuan Earthquake
dammed lakes
remote sensing analysis
risk evaluation
