基于GIS的承德市终霜冻灾害等级划分与风险区划

The Final-frost Disaster Grade Division and Risk Zoning in Chengde City Based on GIS

利用19652018年承德市各县区气象站点的地面0 cm最低温度观测数据、承德市民政局提供的乡镇历史灾情数据及社会经济数据,从终霜出现的时间和强度2个方面构建综合霜冻指数,采用加权评价法与标准差分级法制定适应于山区的终霜灾害危险等级评价标准。在此基础上,从致灾因子、孕灾环境、承灾体3个方面建立终霜灾害风险评估模型;采用层次分析法结合GIS空间分析技术,制作精细化的终霜灾害风险区划图。综合霜冻指数与农作物受灾面积的相关系数为0.67,承德市终霜灾害的高风险区与次高风险区主要位于平泉市、围场县、丰宁县大部、滦平县大部和隆化县北部,低风险区位于市区、营子区、宽城县、承德县中西部和兴隆县中南部地区。综合霜冻指数评价法能根据灾情科学地划分霜冻灾害危险等级,承德市中北部县区的终霜冻灾害风险大于承德市南部地区的风险等级。

Using the observation data of lowest temperature of 0 cm above surface ground at the weather stations in various counties and districts of Chengde City from 1965 to 2018,the historical disaster data of villages and towns as well as the socio-economic data provided by the Civil Affairs Bureau,the comprehensive frost index is constructed from the time and intensity of the end frost.The weighted evaluation method and the standard difference classification method are adopted to formulate the final frost hazard evaluation standards suitable for mountainous areas.On this basis,a final frost disaster risk assessment model is established from the three aspects of hazard factors,disaster-pregnant environment and disaster-bearing body.Moreover,a refined final frost disaster risk zoning map is made by using analytic hierarchy process and GIS spatial analysis technology.The correlation coefficient between the comprehensive frost index and the affected area of crops is 0.67.The high-risk and second-high-risk areas of Chengde City’s final frost disaster are mainly located in Pingquan City,Weichang County,most of Fengning County,most of Luanping County,the northern part of Longhua County,while the low-risk areas are the urban area,Yingzi District,Kuancheng County,the central and western part of Chengde County,and the central and southern part of Xinglong County.In general,this comprehensive frost index evalua-tion method can be used to scientifically classify the risk of frost disaster according to the disasterous situ-ation.The risk of final frost disaster in the north-central counties of Chengde City is greater than that in the southern part.