湄公河干流洪水洪灾特点及防洪对策研究

湄公河是一条著名的雨洪河流,单位面积洪峰流量接近全球雨洪河流的极限值,洪灾频繁。为了减少洪灾损失,对湄公河干流的水系特征、洪水特性和洪灾特点进行了全面分析和分段论述;在此基础上探讨了洪灾成因,总结了防洪特点,并结合国内外防汛实践,提出了防洪对策。结果表明:湄公河干流洪水峰高量大,历时较长,河道洪水来量与泄洪能力不足的矛盾十分突出;洪水地区组成复杂,洪水来源以左岸支流为主,洪水类型以区域性洪水为主;湄公河三角洲漫滩、回流及潮流运动巨大,左右岸、河湖之间防洪关系非常复杂,宜按照"以人为本,人水和谐"的治理原则和"以泄为主,泄蓄兼筹"的防洪方针,科学处理蓄泄关系和河湖关系,对上下游、干支流洪水治理做出全面规划,并以中下游、三角洲地区和洞里萨湖区为规划重点,在充分利用河网、湿地、湖泊蓄泄洪水的基础上,因地制宜采取堤防护岸、河道整治、防洪水库等工程措施与非工程措施相结合的防洪体系;加强湄公河流域各国的防洪减灾合作,做到河湖两利,左右岸兼顾,上下游、干支流相协调相结合,保证重点防洪保护区人民群众生命财产安全,使得防洪减灾由被动防汛到主动迎汛,由单纯抵御洪水到安全管理洪水转变。

Flood characteristics and flood control countermeasures in mainstream Mekong River

Mekong River is a rain-fed river, which is prone to heavy rainfall and flooding. Peak flow per unit area is close to the upper limit value of global rain-fed rivers. To reduce the flood damages, drainage and flood characteristics of Mekong River were thoroughly analyzed and discussed in sections. We also discussed the causes of flood, flood control features and put forward the countermeasures by referencing the flood control practices at home and abroad. The result show that:① the flood process of Mekong River is characterized as high peak, large quantity and long duration, the contradiction between flood quantity and flood discharge capacity is prominent. ② the flood area composition is complex, the main source of flood is from the left bank tributaries, and the main type is regional flood.③ the back flow and tidal movement of the flood plain in the Mekong Delta region are furious, making the flood control more complicated in Mekong river banks and the Tonle Sap lake; therefore, flood control should comply with the principles of “people-oriented, human-water harmony”, and policy of “discharge-oriented, and to have both discharge and storage functions”, storage-discharge relationship and river-lake relationship should be treated in a scientific manner. ④ it is necessary to have a comprehensive plan regarding the flood control in the upstream, downstream, mainstream and tributaries of the river, while more efforts should be put to its middle and lower reaches, as well as Mekong Delta region and Tonle Sap lake area; ⑤on the basis of making full use of flood control function of existing river network systems, wetlands and lakes, a comprehensive flood control system including both non-engineering and engineering countermeasures, such as embankments and revetment, river regulation and reservoirs. ⑥ deepening international cooperation in flood control and disaster mitigation so as to achieve a coordination in rivers, lakes, and the whole basins, to ensure people’s lives and property in the key flood control protection areas,to be more initiative and active in flood controlling, and to improve safety management level.