城市水涝灾害的生态机理分析和思考——以杭州市为主要研究对象

Analysis of ecological mechanism of urban flood and waterlog--Research based mainly on Hangzhou City

随着城市化建设快速发展 ,水涝灾害也日趋严重 .杭州市是一个典型例子 .城市水循环系统是自然循环系统与人工循环系统的合成体 ,是城市居民重要的生存环境 ,利用生态学的系统整体原理去分析城市化对自然水文系统产生的严重影响 ,可以了解城市水涝灾害发生的机理 :城市热岛使气候变化、暴雨增加 ;湿地占用导致滞留容量急减 ;地表硬质化、排水管网化、河堤人工化导致地表径流增加 ,汇流时间缩短 ;水土流失、围湖造田、建闸筑圩抬高了外河水位使排水堵塞 ;供、排水量的失衡与随意引水配水导致流域水文失调 .建议加强城市建设管理的科学性、注重生态系统的整体性 ,尊重自然 ,更新观念 ,建立新的人工水循环系统 .

With the development of urbanization, the city water logging problem becomes more and more serious. Hangzhou is an example. The artificial and natural water cycle system comprise the city's water system, which is an important habitation environment for residents. The authors applied ecological theory to analyze the hydrological influence of urbanization and studied the mechanism of the city's waterlog. Head island effect leads to rainy climate. The filling of many everglade areas has reduced the city's flood holding capacity. Harder urban surface, pipe drainage and remedy riverbank improve the drainage capability, and the conflux time decreases and the surface runoff increases. Soil and water loss, and impoldering of lakes are main causative causes of the city's waterlog. The authors suggest that people should improve the management of the city's civil construction program and keep water environment balanced.