海南山洪灾害调查评价成果及规律分析

Analysis on the Results and Laws of Investigation and Evaluation of Flash Floods in Hainan

海南是我国的暴雨中心之一,降雨主要受热带气旋影响,强度大、时空分配不均,易形成山洪灾害。全省共有18个市县划入国家实施的山洪灾害调查评价范围。通过调查评价,掌握了山洪灾害防治区的范围、人员分布、下垫面情况等特征,以此为基础分析了小流域洪水特征,分析了重点沿河村落的现状防洪能力和预警指标。在此基础上,通过分析防治区、人口、历史山洪灾害、承灾能力的空间分布规律,得到了海南岛山洪灾害易发区主要集中在北部、东部沿海人口密度高、经济较发达、地形平缓的地带,分布于万宁、儋州、文昌、琼海、临高、琼中、昌江等地的特征。因此,需进一步加强这些地区山洪灾害防治非工程措施和工程措施的体系建设,同时拓展山洪灾害调查评价成果数据的应用,不断提高山洪预警和防御能力。

Hainan is one of the rainstorm centers in China;rainfall is mainly affected by tropical cyclones,large intensity,and uneven temporal and spatial distribution,easy to form flash floods.A total of 18 cities and counties in the province were included in the scope of investigation and evaluation of flash floods implemented by the state.Through investigation and evaluation,the scope,personnel distribution and underlying surface of flash floods prevention and control area were grasped,on the basis of which the flood characteristics of small watershed were analyzed,and the current flood control capacity and early warning index of key villages along the river were analyzed.On this basis,through the analysis of the spatial distribution law of flood prevention and control area,population,historical flash floods and disaster bearing capacity,the characteristics of mountain flood disaster in Hainan were summarized:the mountain flood disaster prone areas of Hainan Island are mainly concentrated in the northern and eastern coastal areas with high population density,developed economy and gentle topography,and distributed in Wanning,Danzhou,Wenchang,Qionghai,Lingao,Qiongzhong,Changjiang and other places.It is necessary to further strengthen the system construction of non-engineering measures and engineering measures for the prevention and control of mountain torrents disasters in these areas,expand the application of data from the investigation and evaluation of mountain torrents disasters,and constantly improve the ability of mountain torrents early warning and prevention.