灾害链型巨灾风险评估方法研究——基于汶川地震、西南特大连旱案例

This study discussed the characteristics of sudden and slow-onset large-scale disasters (LSD) based on the case studies of Wenchuan Earthquake in 2008 and tremendous drought disaster in SW China during 2009-2012; and the definition and division criterion were explored based on the LSD cases of the world in recent years. The conceptual model of hazards chain (one hazard induced by another one) and the vulnerability change of the disaster-affected bodies under the hazard-formative environment's mutations was built, based on the regional disaster systematic theory. The study also built a three-dimension model of LSD risk assessment, consisting of "comprehensive stability of disaster formative environment", "comprehensive hazard", and "comprehensive vulnerability of disaster-affected bodies". The LSD risk was implemented on the three scenes, including sudden and slow-onset disaster chain, normal and sudden mutation environment, and different types of disaster-affected bodies, e.g. population, houses and crops. And the measures to reduce the regional LSD risk was discussed from the aspects of hazards chain and vulnerability of disaster-affected bodies, and then the LSD adaptation suggestions and strategies based on "breaking the hazards chain" and "reducing the vulnerability " were proposed in the study. It can provide an important reference to accelerate the development of disaster risk science and regional disaster systematic theory, and to enhance the LSD risk governance at the national and regional scale.

以汶川特大地震灾害、2009-2012年西南特大连旱灾害为案例，梳理突发性与渐发性巨灾特征；结合近年来全球重特大自然灾害案例，界定巨灾定义与划分标准；基于区域灾害系统理论，构建孕灾环境突变情景下致灾因子链发及承灾体脆弱性变化过程的概念模型；建立灾害链巨灾风险评估的"孕灾环境综合稳定性"、"致灾因子链综合危险性"和"承灾体综合脆弱性"的"三度"模型，分突发性与渐发性灾害链情景、孕灾环境常态与突变情景以及人口、房屋和农作物等承灾体类型情景开展巨灾风险评估。从致灾因子链和承灾体脆弱性两方面，探讨区域减轻巨灾风险的举措，提出"断链"与"降低脆弱性"相结合的巨灾风险综合适应策略。以期为推动灾害风险科学的发展和灾害系统理论的深化与创新，提升国家巨灾风险防范水平提供科学依据。

中国作为世界上少数几个自然灾害频发、损失严重的国家之一，近年来巨灾时有发生。巨灾事件多数是由高强度的单一（或多个）致灾因子引起的灾害链所致，灾害链在灾情形成过程中起到了明显的放大效应。实践证明，巨灾虽不可避免但可以防范，掌握巨灾风险格局及变化规律，就可在与巨灾风险共存中求得可持续发展，从而降低灾害损失。本研究以汶川特大地震灾害、2009-2012年西南特大连旱灾害为案例，梳理突发性与渐发性巨灾特征，基于区域灾害系统理论，界定巨灾概念与标准，首次明确渐发性巨灾标准，填补了渐发性巨灾划分标准的空白。开展地震灾害链巨灾过程研究，建立基于“Newmark”的地震灾害链孕灾环境敏感性分析指标与阈值确定方法；开展干旱灾害链巨灾过程研究，建立基于“压力—状态”的干旱灾害链承灾体敏感性分析指标与阈值确定方法；开展灾害链脆弱性变化分析，构建基于“国际上通用风险分析框架”的灾害链巨灾风险概念模型。构建汶川地震灾害链巨灾风险评估概念模型，完成极重灾区地震—地质灾害链风险评估；构建西南特大连旱灾害链巨灾风险评估概念模型，引入“S型曲线”完成案例区灾害链风险评估。基于致灾因子链发与动态脆弱性特征和全过程视角，构建灾害链型巨灾风险适应策略分析框架；从脆弱性、恢复性等关键科学问题入手，提出突发性巨灾“风险—应急—危机”适应策略，渐发性巨灾“风险∪危机—风险”适应策略。本项目丰富和完善了区域灾害系统理论，为推动灾害风险科学的发展和灾害系统理论的深化与创新、提升国家巨灾风险防范水平提供了重要理论支持与案例实践。截至2015年12月31日，共公开发表研究论文7篇，其中SCI期刊论文2篇，撰写专著1部，联合培养博士研究生1名。