长沙市区灾害性洪水形成机制分析

Causing Mechanism Analysis of Disastrous Flood in Changsha City

长沙市区灾害性洪水所造成的损失十分严重 ,是全国 31个重点防洪城市之一 .从气候特征、湘江中上游洪水沿程迭加、区间洪水的复合作用、洞庭湖洪水抬高顶托、湘江河道堵支和洲滩围垦、城市建设侵占河道和滞洪洼地、防洪工程存在较多问题、城市防洪减灾管理体制不够完善等方面综合分析了长沙市灾害性洪水的形成机制 ,为灾害性洪水的预测预报。

The loses caused by disastrous flood is far too serious in Changsha city where is among the important cities of flood prevention in China. It is caused by many natural and man-made factors Such as follows: climate features, the addition of flood in the up and middle valley along the Xiang River, the compound function of flood in local region, the supporting function of flood level from Dongting Lake, the blockage of branches and development of beach, the invasion and occupation to the river valley and low-lying land, there being many problems in the prevention engineering, the administrative system of urban flood prevention being still less better. This study will serve as the scientific basis for flood forecast, plan-making of flood prevention and formulating countermeasures of disaster reduction.