基于GIS的阿克苏地区冰雹灾害风险区划及评价

GIS-Based Hail Risk Zonation and Assessment in Aksu Prefecture

以阿克苏地区1984-2007年冰雹灾害、1959-2007年气象站点冰雹日数及DEM数字高程模型、土地类型等资料为基础,选取对雹灾有影响的高程、下垫面、冰雹路径、冰雹频率、雹灾次数、人口、GDP、耕地分布等作为评价因子;借助ArcGIS的空间内插、密度、叠加、缓冲区等分析功能,建立各因子图层,参与冰雹敏感性、危险性、易损性的分析运算;最终建立风险区划模型,进行叠加分析,完成阿克苏地区冰雹灾害风险区划。区划的结果体现了GIS的优势,比以前的区划更加明确,能更准确地定位各类风险区。对于不同的风险区域,采取针对性的防治措施,能最大限度地减少冰雹灾害带来的损失。

Aksu Prefecture is one of the regions where hail disaster occurs frequently in Xinjiang. In this paper, elevation, underlaying surface, hail routes, hail disaster frequency, times of hail disaster, population, GDP and farmland distribution affecting hail occurrence were chosen as the estimation factors in the zonation and assessment of hail disaster in Aksu Prefecture, Xinjiang based on the data of hail disaster during the period from 1984 to 2007, days of occurring hail from the meteorological stations during the period from 1959 to 2007, DEM, land use types, etc. All the factor layers were obtained by using the analysis methods of interpolation, density, overlay, buffer, etc. of ArcGIS, and then all the factor layers were taken into account in analyzing and calculating the hail sensitivity, disaster hazard and vulnerability. Finally, the mathematic models of hail risk zonation were developed to carry out the overlaying analysis and accomplish the hail risk zonation in Aksu Prefecture. The advantages of GIS were utilized in the zonation, and the various hail risk areas were delimited more accurately compared with other previous zonations. The losses caused by hail disaster could be farthest reduced by taking the proper measures.