摘要
基于自然灾害风险理论,借助GIS强大的空间分析功能,采用归一化和层次分析法,对中国全国范围尺度进行了洪涝灾害危险性评估。通过对洪涝灾害危险性因子分析,分别提取当天降雨量、前3 d降雨量、地形高程、地形标准差、河湖网络等因素作为评估因子,提出了各因子危险性指数计算方法,以及全国洪涝灾害危险性指数计算模型公式。根据统计分析危险指数的最小值、最大值,结合历史灾情,利用阈值分割法确定了风险等级分割值分别为0.3、0.45及0.6,将洪涝灾害等级划分为高风险、中风险、低风险与无风险四个等级,从而建立了类似于天气预报模式的全国洪涝灾害危险性评估模型,并以2010年8月22日为例进行了洪涝灾害危险等级评估的实际应用。最后,基于洪涝灾害的危险性评估的结果,结合危险区内人口分布、交通设施等基础数据,生成相应的预警产品。对可能发生的洪涝灾害发出预警与预测,为危险区人们乃至相关政府管理部门采取有效的防灾、减灾措施提供参考依据。
based on the theory of natural disaster risks and by means of the powerful spatial analytic tool of GIS as well as the normalization and analytic hierarchy process,national-scale assessment of flood disaster risk in China is conducted.According to analysis on flood hazard factors,precipitation of the current day and last three days,topographic elevation,topographic standard deviation,net work of rivers and lakes respectively are extracted as assessment factors,methods of flood hazard factors’ computation and the models of flood hazard indexes in China are put forward.Combined with disasters records,and based on analysis of the minimum and maximum of hazard indexes by statistic method,risk level split value are determined as 0.3,0.45 and 0.6 by using thresholding method,and the flood hazard degrees are divided into four levels： high,medium,low and zero.A flood hazard assessment model,similar to weather forecast,was thus established,and its first practical application is in the assessment of flood hazard on 22nd Aug.2010.Finally,based on basic data as results of flood hazard assessment in hazard areas,transportation facilities and so on,corresponding warning products are generated.Early warning and prediction are done to possible floods for people as well as governments to take effective disaster prevention and mitigation measures.
出处
《灾害学》
CSCD
2011年第3期8-12,17,共6页
Journal of Catastrophology
基金
国家自然科学基金“洪泛湿地水文生态过程的防洪效应研究”(40701172)
国家“八六三”计划(2009AA12Z124)
国家科技支撑计划(2008BAC44B03)
关键词
评估模型
洪涝灾害
洪涝预警
地理信息系统
assessment model； flood disaster； flood early warning； Geographic Information System（GIS）
