中文摘要：

准确掌握旱灾时空演变规律对旱灾防灾减灾具有重要意义.利用EOF对标准化降雨指数（SPI）做正交分析,得到松辽流域一年四季旱灾时间分布规律;同时,利用GIS技术与小波分析对松辽流域一年四季旱灾空间分布进行可视化及空间分布特征分析.研究结果表明：（1）从时间上表现为划分出三个震荡比较明显的时期;（2）从空间上春季旱灾具有东西向变化特征,东部与西部存在差异;夏季旱灾具有西南向东北走向,并且该特征的变化具有明显的6-12增减周期;秋季旱灾具有南北分异性,该分布差异强弱在1990年之前具有明显的4-8年周期震荡变化,1990年之后强弱变化周期不明显;冬季旱灾具有西北向东南的分异性,该分布差异强弱在1990年之前具有明显的6-10年周期震荡变化,1990年之后强弱变化周期变为2-6年,整体长期趋势为缓慢减弱趋势.研究结果可为当地旱灾防灾减灾及应急管理提供决策依据.

英文摘要：

Accurate grasp of the temporal and spatial evolution of drought has important significance for the drought disaster prevention and reduction. Using EOF to make the orthogonal analysis of the standard rainfall index （SPI） ,the time distribution of drought in the Songliao River Basin was obtained. Meanwhile, the spatial distribution of drought in the four seasons of the Songliao Basin was analyzed by using GIS technique and wavelet analysis. The results showed that：there are obvious differences between eastern and western, Eastern and western, and the change of 6 -12 has obvious 4 -8 years. In 1990,the difference is not obvious. In 1990,the difference of winter drought has obvious 6 ~ 10 years, and the long-term trend is 2 - 6 years, and the trend is slow and weak. The research results can provide the decision-making basis for the local drought disaster prevention and reduction and emergency management.