中文摘要：

利用石羊河流域区1960-2011年气候要素资料，分析了石羊河流域干旱灾害空间分布、年际和年代际变化特征；结合致灾因子的危险性、孕灾环境脆弱性、承灾体的暴露度和防灾减灾能力评价等指标进行基于 GIS的石羊河流域干旱灾害风险评估与区划。结果表明：1960-2011年，石羊河流域春旱发生频率在21．2％～67．3％之间。春季特旱发生频率下游区域大于中上游区域。初夏干旱发生频率在13．5％～61．5％之间。初夏特旱发生频率下游区域也大于中上游区域。伏旱发生频率在21．2％～86．5％之间。伏期特旱发生频率下游区域亦大于中上游区域。石羊河流域干旱综合风险高风险区为民勤县和金川区大部、凉州区中北部、永昌县东部，位于石羊河流域的中下游区域。就各县区而言，干旱灾害综合风险最大的区域为石羊河下游的民勤县，金川区次之，天祝县风险低。

英文摘要：

Based on the meteorological observational data in Shiyang River basin from 1961 to 2010 ,the character-istics of spatial ,interannual and decadal drought disaster distribution were analyzed .According to the dangerousness of disaster factors ,vulnerability of disaster bearers ,exposure degree of hazard-bearing bodies and capability of disaster pre-vention and mitigation ,the assessment and regional division of drought hazard risk in Shiyang River basin were conducted based on GIS .The results showed that the frequency of drought in spring ,early summer and hot summer during 1960 -2011 was 21 .2% ~ 67 .3% ,13 .5% ~ 61 .5% and 21 .2% ~ 86 .5% ,respectively ,and the frequency of particular drought in spring ,early summer and hot summer in down - stream areas was wholly higher than that in up-middle stream areas .The areas with high comprehensive drought risk included Mingqin County ,most part of Jinchuan District ,north and central part of Liangzhuo District and east part of Yongchang County ,where were located in the mid-down stream of Shiyang River basin .Among the studied counties and districts ,Mingqin County located in the down-stream was the high-est in comprehensive drought risk ,followed by Jinchuan District ,and Tianzhu County was the lowest in drought risk .