全国区域洪水风险评价与区划图绘制研究

利用近300年水灾资料序列及当前自然和社会经济基础数据,采用统计学和模糊聚类的方法,在数据库和GIS技术支持下,完成了区域洪水风险分析及全国洪水风险区划图的绘制。本论文的主要进展是:提出区域洪水风险评价的指标体系,即自然特性(水文和地形)、社会经济(人口、GDP和土地面积)、洪水灾害(灾害场次和最大淹没面积)、减灾能力(防洪标准)4类特性指标;以县为区域洪水风险分析的基本单元,组成区域洪水灾害的10个影响因子和2400个县的分析样本,从而取得了宏观定量的区域洪水风险评价及洪水风险分区成果;采用历史水灾频率法界定了重点风险区边界,从而完成了以县为边界的全国洪水风险区划图的绘制。

Research on regional assessment of flood risk and regionalization mapping in China

Based on 300 years' (1700 to 1999 A.D.) historical records of floods and the data-base of present natural and socio-economica situations, the authors conducted regional flood risk analysis and established a characteristic indicator system for flood risk regionalization mapping by applying the methods of statistics and fuzzy classification. The proposed characteristic indicator systems included 4 kinds of indices: natural characters (hydrological data and geomorphologic element); social and economical characters (population, GDP and land area); flood disasters characters (disaster events and largest inundation areas over 300 years' period) and disaster mitigation character (flood control criteria). In the analysis, county was taken as the basic element and the whole mapping system involved 2400 counties and 10 influencing factors. The historical flood frequency method was employed for defining the major risk zones and ranking hazardousness of the 2400 counties.