Analysis of the impact of urbanization on regional flood risk: A case study in the Qinhuai River Basin, China

Qinhuai River Basin is located in the lower reaches of Yangtze River. With acceleration of urbanization, the flood risk of basin has increased and threatened blood and treasure of people. Based on RS and GIS methods, the impact of urbanization on the flood risk was analyzed in space and time. The study showed that, (1) Urbanization aggravated the flood risk. The space distribution of urbanization and flood risk showed consistency. (2) From 1994 to 2001, the flood risk of south of Nanjing city proper and areas along Yangtze River increased. From 2001 to 2008, areas of increased flood risk migrated upwards along Qinhuai mainstream. Until 2008, the flood risk along Qinhuai mainstream was higher. (3) The flood prevention pressure of Nanjing city proper and new urban region of Jiangning district augmented. Construction and control of integrated water conservancy project should be strengthened and meteorological forecast ability should be promoted.