西南地区公路洪灾孕灾环境分区

ZONATION OF HIGHWAY-FLOODING IN SOUTHWEST CHINA BASED ON HAZARD-INDUCING ENVIRONMENTAL FACTORS

以西南地区公路洪灾为研究对象,在孕灾因子分析基础上构建由6个因子组成的孕灾环境分区指标体系,利用层次分析和专家效度相耦合方法确定各指标权重,采用综合指数法建立孕灾环境综合指数评价模型。在Arc-GIS软件平台支持下获取各评价指标数据,并计算得到各网格孕灾环境综合指数值,以县级行政区为单位进行公路洪灾孕灾等级区的划分。研究表明:西南地区孕育公路洪灾发生的环境条件较充分,孕灾环境综合指数值在33.13～77.46,孕灾分区主要集中在中易发区和高易发区,其中高易发区占整个研究区面积的57.18%,中易发区占40.39%,低易发区占2.43%,公路管理部门在汛期防治洪灾的任务较繁重。

The paper studies highway flooding in Southwest China,and 6 factors including developing conditions for geological disasters,geomorphological conditions,geological lithology,average annual rainfall,vegetation coverage and geological-tectonic conditions along the highway have been selected to construct the Index System of hazards inducing environment zoning.The index weight were obtained through the combination of AHP and expert reliability,and the comprehensive index evaluation model for hazards developing environment was built.Supported by ArcGIS,comprehensive index for hazards developing environment in each grid was calculated by the analysis data of each index precisely obtained through 1 km×1 km grids,then hazards developing environment of highway flooding in Southwest China were devided into different zones according to county administrative districts.The results show that Southwest areas have sufficient environment conditions for highway flooding,the comprehensive index of hazards developing environment ranges from 33.13 to77.46,and the hazards inducing environment zones are mainly distributed in high easy-happening area and medium easy-happening area,among which high easy-happening area,medium easy-happening area and low easy-happening area acounts for 57.18%,40.39%,4.42% of the total area.This brings a heavy burden to highway management and operation.