基于投影寻踪原理的四川省洪灾评估

以四川省1976—2006年洪灾资料为基础,选择体现洪灾损失特性的相对受灾人口、死亡人口、洪灾经济损失和农作物受灾面积4个指标数据,采用投影寻踪法建立了四川省洪灾程度评估模型,并利用该模型计算了四川省洪灾程度综合指标,对其进行分级评估。计算结果表明:四川省是洪灾较为严重的省份,近30年来每10年期受灾程度分布类似,在各期内均发生特大灾害1次,大灾害3～4次,且灾害程度随时间并未出现减弱、减小的趋势;同时,洪水量级排序和灾害级别大小并不一致。

Assessment on flood disaster in Sichuan Province based on the principle of projection pursuit method

Based on the data of the flood losses in Sichuan Province from 1976-2006, a model for assessing the degree of flood disaster in Sichuan Province based on pursuit projection method is established. In the model, the population of disaster area, the number of dead, the comparative economic loss due to the floods and the stricken agricultural area by flood are the main indexes. The result indicates that Sichuan Province has been severely suffered from flood disaster, and the distribution of flood is similar every 10 years in recent 30 years. It also shows that disaster happens in each 10 years, in which 3 or 4 are severe. The degree of disaster does not change with time. The flood volume and the disaster grade are not compatible.