摘要
西南山区低频山洪泥石流灾害时常引发村寨群死群伤。该文以2024年四川汉源“7·20”山洪泥石流为例,采用实地调查与无人机影像信息挖掘相结合的方式,研究剖析灾损构成及灾害成因。结果表明:该灾害演化呈“点暴雨—山洪—泥石流”链式过程,导致临沟建筑物、农田及交通基础设施系统性损毁。桥梁选址于汇流节点、建筑侵占洪道等规划失序问题,加剧了“冲击—淤埋—堵溃”复合致灾强度,主支沟交汇区能量叠加,导致损毁建筑物核密度达到峰值,低频灾害中支沟风险突出;地震与山洪泥石流风险博弈失衡、社会认知缺位、预警响应脱节及工程适灾不足,显著提升承灾体脆弱性。研究结果可为西南山区村寨综合防灾减灾策略的制定提供科学依据。
Low-frequency mountain torrent and debris flow disasters in southwestern China's mountainous regions frequently trigger catastrophic village casualties.Taking the"7·20"debris flow in Hanyuan,Sichuan(2024)as a representative case,a combination of field investigation and unmanned aerial vehicle(UAV)image information extraction is adopted to analyze disaster damage composition and causation mechanisms.Results indicate that the disaster evolved through a"localized torrential rain--mountain torrent--debris flow"chain process,causing systematic destruction of gully-adjacent buildings,farmland,and transportation infrastructure.Planning irregularities such as bridges placement at confluence nodes and buildings encroaching flood channels exacerbated compound disaster intensities characterized by"impact--siltation--blockage".Energy accumulation at maintributary gully confluence zones led to peak kernel density of destroyed buildings,with tributary gullies demonstrating pronounced risks under low-frequency events.Key factors included imbalanced seismic-debris flows risk management,lack of low-frequency disaster preparedness,societal awareness deficits,disjointed early warning-response systems,and inadequate engineering resilience,are collectively heightening the vulnerability of disaster-bearing systems.These findings offer scientific foundations for formulating integrated disaster prevention and mitigation strategies tailored to southwestern mountainous villages.
作者
谢雨岑
骆晓龙
牛志攀
李鑫蕾
张斌
贺文
彭巧巧
孟祥瑞
第宝锋
XIE Yucen;LUO Xiaolong;NIU Zhipan;LI Xinlei;ZHANG Bin;HE Wen;PENGQiaoqiao;MENG Xiangrui;DI Baofeng(Institute for Disaster Management and Reconstruction,Sichuan University–The Hong Kong Polytechnic University,Chengdu 610207,China;Center for Archaeological Science,Sichuan University,Chengdu 610045,China;Bureau of Emergency Management of Ya'an,Ya'an 625000,China;School of Geographical Sciences,China West Normal University,Nanchong 637009,China)
出处
《灾害学》
北大核心
2025年第4期157-164,共8页
Journal of Catastrophology
基金
国家重点研发计划项目“重大自然灾害防控与公共安全”(2024YFC3012702)
国家重点研发计划项目“九寨沟遗产地震损物源输移与湖泊淤积智慧防控策略”(2023YFE0121900)
国家自然科学基金项目“气候干湿循环作用与区域泥石流重现准周期的遥联关系研究”(42377168)。
关键词
山洪泥石流
点暴雨
灾损特征
灾害成因
综合减灾
mountain torrent and debris flow
localized torrential rain
disaster damage characteristics
disaster cause
comprehensive disaster reduction
