城镇化背景下我国城市洪涝灾害演变特征

基于1990—2015年全国洪涝灾情数据，采用数理统计、GIS技术、灰色关联分析等方法，研究快速城镇化背景下我国城市洪涝灾害的时空分布演变特征，以及洪涝灾害指标与城镇化率之间的相关关系。研究结果表明:我国城市洪涝灾害呈南重北轻、中东部重西部轻的空间分布格局，洪灾频繁的城市主要位于长江中下游城市群、成渝城市群、珠三角城市群，分布在长江流域、珠江流域；随着我国城镇化进程的不断加快，各城市洪涝灾害总次数先减小后又逐步增加，洪灾频繁的城市由北向南转移；我国城市洪涝死亡人口和受灾人口年际变化较大，存在一定突发性，但总体上均表现出下降的趋势，直接经济损失随时间呈现增加的趋势，城市洪涝死亡人口、受灾人口和直接经济损失与城镇化率之间均呈较强关联。

Study on evolvement law of urban flood disasters in China under urbanization

Based on the national flood disaster data from 1990 to 2015, the evolvement characteristics of the urban flood disasters and the relationship between Chinese flood disaster and urbanization rate were explored mathematical statistics, GIS technology, gray correlation analysis and other methods. The results indicate that the urban flood disasters in southern and mid-eastern China were more serious than those in the northern and western regions. Cities suffering frequent floods were mainly distributed in the Yangtze River Basin and the Pearl River Basin, especially among the urban agglomerations of the middle and lower reaches of the Yangtze River, Chengdu-Chongqing region and the Pearl River Delta. With the rapid urbanization in China, the total number of urban flood disasters decreased first and then gradually increased. Meanwhile, the frequency of flood disasters dropped in the north and rose in the south. The interannual affected and dead population due to urban flood disasters had great and occasional variations, whereas both had a decreasing trend in general. However, economic losses have generally rose over the time. It was shown that the dead and affected populations and direct economic losses were strongly correlated with the urbanization rate.