城市雾霾灾害链演化模型及其风险分析

Evolution model and risk analysis of urban haze disaster chain

采用灾害系统理论及复杂网络理论,开展了城市雾霾灾害链演化模型构建及其风险分析。基于雾霾的成因及危害,从致灾因子、孕灾环境和承灾体特征出发,分析了城市雾霾灾害链的成灾机制及其灾害链的类型与特征。通过构建城市雾霾灾害链演化网络模型,基于网络节点的出入度及其子网节点数、最短路径和平均路径与包含节点的支链数进行了定性风险分析,进一步确定关键环节,提出了断链减灾的控制建议。风险分析的结果表明：在城市雾霾灾害链演化系统中,雾霾事件与其他危机事件之间联系十分紧密,通过几次过渡,其危害影响就能蔓延到整个网络,其中大气能见度下降、空气质量下降或空气污染、交通堵塞或瘫痪、交通事故、城市大气酸雨、危害城市绿化、经济损失和危害人身体健康是关键环节。

Evolution model and risk analysis of urban haze disaster chain are carried out on the basis of disaster system theory and the complex network theory in this paper. Through the information gathering and analysis of the causes and harm of urban haze disaster, the disaster chain mechanism of urban haze is analyzed, as well as the types and characteristics of disaster chain, according to the characteristics of disaster-causing factors, hazard-formative environment and hazard-affected bodies. By building the urban haze disaster chain evolution network model, qualitative risk analysis is made based on the out-in degrees and number of nodes in its subnets, the shortest path and average path, and the number of branched chains. Finally, the key steps are found and the solutions on disconnecting chains are presented. The results of risk analysis show that in the urban haze disaster chain evolution system, the haze event closely relates to the other crisis events. Through several times of transition, the harm effect might spread to the entire network, and the key links are the decline in atmospheric visibility, the decline in air quality or air pollution, traffic jams or paralysis, traffic accidents, resulting in urban atmospheric acid rain, urban greening, economic losses and endanger human health.