甘肃省河东地区气象干旱灾害风险评估与区划

干旱灾害是世界上危害最为严重的自然灾害之一。通过对干旱灾害风险成因的深入分析,结合灾害学理论,从干旱灾害的致灾因子危险性、孕灾环境脆弱性、承灾体暴露性和防灾减灾能力等4个方面入手,构建干旱灾害风险评估模型,然后依据甘肃省河东地区相关气象、生态和社会经济数据,在GIS平台下将干旱灾害的自然属性和社会属性统一起来进行干旱灾害风险评估与区划。结果表明:(1)研究区致灾因子危险性等级有自中部向东西两边逐渐降低的趋势,7个地区中干旱灾害危险性自大到小依次是天水、平凉、陇南、定西、临夏、甘南和庆阳。(2)研究区孕灾环境脆弱性有自北向南逐渐降低的趋势,脆弱性自大到小依次是庆阳、临夏、定西、平凉、天水、甘南和陇南。(3)研究区承灾体暴露性自大到小依次是天水、平凉、临夏、定西、陇南、庆阳和甘南。(4)防灾减灾能力自大到小依次是临夏、天水、平凉、定西、陇南、庆阳、甘南。(5)河东地区自北向南干旱灾害风险逐渐降低,干旱风险自大到小依次是定西、天水、庆阳、平凉、临夏、甘南和陇南。

Assessment and Regionalization on Meteorological Drought Disaster Risk in the Hedong Area of Gansu Province,China

Drought disaster is one of the most hazardous natural disasters on earth. Through the in-depth analysis of causes of drought risk, combined with the principles of natural disaster system, a drought disaster risk assessment model was constructed according to the dangerousness of disaster-inducing factors, vulnerability of disaster-breeding environment, exposure of disaster-bearing body, and disaster prevention and mitigation capabilities. Then, an assessment and regionalization of drought risk was conducted in Hedong area of Gansu Province with ArcGIS platform by integrated consideration of the natural and social characteristics of drought disaster, based on local meteorological, ecological and socio-economic data. The results showed that: (1) The dangerousness of disaster-inducing factors decreases gradually from the middle to both west and east sides of Hedong area, and from large to small is Tianshui, Pingliang, Longnan, Dingxi, Linxia, Gannan and Qingyang. (2) The vulnerability of disaster-breeding environment decreases gradually from north to sourth, and from large to small is Qingyang, Linxia, Dingxi, Pingliang, Tianshui, Gannan and Longnan. (3) The exposure of disaster-bearing body is the highest in Tianshui, followed by Pingliang, Linxia, Dingxi, Longnan, Qingyang and Gannan. (4) The disaster prevention and mitigation capabilities from large to small is Linxia, Tianshui, Pingliang, Dingxi, Longnan, Qingyang and Gannan. (5) The meteorological drought disaster risk decreases from north to south and the highest in Dingxi, followed by Tianshui, Qingyang, Pingliang, Linxia, Gannan and Longnan.