A networked risk perspective for analysing debris flow losses factors considering mitigation measures

ABSTRACT As debris flow disasters are becoming increasingly severe worldwide, it is necessary to deepen the research on disaster losses, especially the impact and role of disaster mitigation measures. Based on the regional disaster system theory, this paper sets an influencing factor system of debris flow losses. Then, from the perspective of networked risk, the risk propagation network is established through the Delphi method. Finally, the social network analysis method is introduced to discuss the risk propagation relationship between these factors from two aspects of the overall network analysis and node centrality analysis. The results reveal the chain-like influence characteristics of factors and clarify the main points relevant departments should emphasise in disaster risk reduction. Environmental and engineering mitigation measures strongly influence other factors, thus dominating the risk propagation in forming debris flow losses. The peril of debris flow, residents’ escape ability, and emergency rescue can be easily influenced by other factors, so increasing the resistance of these sensitive factors to the source of influence would support loss reduction. The research results can be applied to risk assessment and loss reduction of debris flow disasters.