秦淮河流域城镇化的洪水响应研究

城镇化高速发展对下垫面、水文循环和洪水过程的影响越来越大。以城镇化程度高、速度快的秦淮河流域为例,其中秦淮河下游片、秦淮河中游片为重点研究区,以1986、1996、2002、2006、2010年5个城镇化发展阶段为代表,基于HEC-HMS水文模型定量分析同等降水条件下城镇化对流域出口洪水过程的影响,模拟得出各种设计暴雨与不同城镇化发展阶段的下垫面相组合情景下的洪水过程。结果表明,在所有组合情景下,洪峰及洪量均随着不透水面积率的增加而增大;城镇化发展最快的秦淮河中游片产生的水文响应大于城镇化水平最高但并非速度最快的秦淮河下游片,且整个流域城镇化的洪水响应多半源于两个重点研究区的城镇化发展洪水响应。

Study on Flood Response of Urbanization in Qinhuai River Basin

The impact of the urbanization on the underlying surface, the hydrological cycle and the hydrological process is a matter of great concern in the current hydrographical study. In this paper, the Qinhuai River Basin, which has the rapid development of urbanization and high flood defenses pressure, was selected as the research object, in which the lower Qinhuaihe River and the middle Qinhuai River were the key research areas. The influence of urbanization on the flood hydrological effect in the watershed under the same precipitation condition was quantitatively analyzed with the HEC-HMS hydrological model by the representatives of the five urbanization development stages of 1986,1996,2002,2006 and 2010. The flood process under the combination of various design rainstorm and the underlying surface of different urbanization development stages is simulated. The results show that under all the combined scenarios, the flood peak and flood volume increase with the increase of impervious surface coverage rate. The hydrological response of Qinhuai River, the fastest developing Qinhuaihe River, is larger than that of the lower Qinhuaihe River, which has the highest but not the fastest urbanization level, and the flood response of urbanization in the whole basin is mostly due to the flood response of urbanization development in the above two key research areas.