区域山洪灾害预警难度评价——以长江流域为例

Assessment of the Difficulty of Warning Mountain Torrent Disasters: Case Study of the Yangtze River Basin

灾害预警难易程度评价是我国山洪灾害防治研究的一项基础性课题。基于历史灾害、地理背景、社会经济等数据资料,利用地统计分析方法,从设备投入使用维护环境、致灾过程类型和下垫面复杂性3个方面,初步构建山洪灾害预警难度评价指标体系;并采用层次分析法对各项指标进行打分定权,建立评价模型;最后以长江流域为例,对其山洪灾害预警难度进行评价。结果显示:预警难度较大的区域主要集中在甘肃南部、四川中部、云南北部、贵州东北、湖北西北以及重庆大部分地区,这些地区为滑坡、泥石流多发区,山高坡陡可达性差,设备布设、使用和维护成本高或难以执行,以及经济建设相对比较落后、地区财政压力较大;青海、四川盆地、长江中下游山洪灾害预警难度相对较小,评价结果与典型区实地调研情况有较高一致性。研究结果可为我国山洪灾害防治宏观决策提供新的分析视角和依据。

Assessing the difficulty of early-warning mountain torrent flood disaster is a basic research in the study of mountain flood disaster prevention in China.In this study,we built the assessment index system by using geostatis-tics method based on historical disasters,geographical background,and socio-economic data.The assessment index system includes the types of the torrent flood processes,underlying surface complexity and maintainability and per-formability of equipment.Analytic Hierarchy Process was employed to give weights to various indicators and the as-sessment model was obtained.The model was applied to assess the difficulty of early-warning torrent flood disaster in the Yangtze river basin.Results showed that areas difficult to warning are mainly concentrated in the south of Gansu Province,middle Sichuan province,the north of Yunnan,northeast of Guizhou,Northwest of Hubei,and large parts of Chongqing.These areas are frequently subjected to landslides and debris flows with high mountains and steep slopes unaccessible and high costs of installing and maintaining equipment as well as fiscal difficulty. Qinghai,Sichuan basin,and the middle and lower reaches of Yangtze river are less difficult to warn.The assess-ment results are consistent with field investigation of typical regions.The research results may provide new perspec-tive and basis for policy-making on the control of torrent flood disasters in China.