土地利用变化对洪湖流域洪涝灾害影响

The Impact of Land Use Change on Flood Disaster in the Honghu Lake Watershed

洪湖流域是著名的鱼米之乡,长期遭受洪涝渍害威胁,也是我国血吸虫病流行最严重地区,搞清该地区洪涝的致灾因子很有必要。利用历史上两个典型相似的暴雨强降水过程气象数据、土地利用资料,采用暴雨洪涝淹没模型模拟计算,以及实际洪涝灾情资料进行对比分析。结果表明,洪湖流域水域面积从1995年的11.70%上升至2010年的14.95%,增加的水域面积主要为水产养殖面积;水产养殖导致对洪水承载能力下降,鱼塘面积的大量增加对洪涝灾害确有放大作用,加剧洪涝灾害;真正落实国家"退田还湖"政策,对于保护湿地生态环境十分重要。

The Honghu Lake watershed is a district with abundant fish and rice.The area has suffered long-term flood damage and the most serious schistosomiasis epidemic in China.It is necessary to determine the cause of flooding in this area.Based on meteorology and land use data of two locations with a similar history of heavy rainfall,a“torrential rain flood submergence”model was used to simulate,compare and analyze scenarios.The results showed that the water area ratio in the Honghu Lake watershed increased from 11.70%(in 1995)to 14.95%(in 2010),which is mostly aquaculture area.It also showed that it was aquaculture which lead to a decline in bearing capacity for flooding,which was amplified by an increase in fish pond areas.We conclude that protection of ecological environment in wetland should be carried out by implementation of policy of restoring the lake from the land.