山洪泥石流风险评估与风险管理理论与方法

山洪泥石流是中国常见的自然灾害,充分认识其形成机制与潜在风险是防灾减灾的关键。本文阐述了山洪泥石流形成机理,以及风险分析与管理的方法和内容,系统认识了地表产流流量激增、土体破坏物质供给激增、沟道堵塞体级联溃决流量放大和动床侵蚀规模增大等4个山洪泥石流的形成过程,介绍了基于动力过程的山洪泥石流风险评估方法和承灾体易损性评估方法,构建了基于灾害动力过程的风险评估与风险制图方法。进而,基于风险评估结果,提出可用于具体灾害点减灾的风险管理内容和风险调控技术、灾害防治的工程与非工程措施与制技术方案。最后,重点讨论了包括灾害风险预测、临灾预案、灾害防治工程方案等内容的风险处置对策,并形成一套基于山洪泥石流动力过程的风险评估与风险管理理论与方法体系。

Theory and method of risk assessment and risk management of debris flows and flash floods

Debris flows and flash floods are widely distributed mountain hazards in China. Effective hazard mitigation and prevention require understanding of hazards formation mechanisms and their potential risks. This article elaborates on the formation mechanism, risk analysis, and risk management of debris flows and flash floods. Surface runoff and material supply volume incensement, hazard scale amplification due to outburst of multiple channel blockages and bed erosion as hazard formation mechanism are discussed. Base on the dynamic process of debris flows and flash floods as well as vulnerability assessment of elements at risk, methods of risk assessment and mapping are proposed. Comprehensive engineering and non-engineering measures for hazards control shall be guided by the result of risk analysis that identifies the hazardous level of debris flows and flash floods and incorporates the vulnerability of different elements at risk. Finally, this article discusses strategies when facing risk of these hazards and puts forward a risk management system that involves the participation of local communities.