中文摘要：

基于沂沭河流域近600年历史洪水资料的搜集、整理和分析，对该流域洪涝灾害发生的时空分布特征以及形成原因进行了研究，结果表明：自公元1368年至1950年的近600年间，历史文献记载了该流域共发生洪涝灾害102次，平均每6年发生一次，其中轻度涝灾45次，占洪涝灾害总数的44．1％；中度涝灾37次，占36．2％；大涝灾16次，占15．6％；特大洪涝灾害4次，占4．1％．“明清小冰期”频繁变化的气候特征、流域地貌特征和河道变迁是洪涝灾害发生的主要原因．

英文摘要：

Through collecting, sorting and analyzing data of flood occurrences in Yishu River Basin in the past 600 years ,the spatial and temporal distribution as well as the causes of the flood disasters in this basin were studied. The result showed that there were 102 flood disasters recorded according to historical documents during about 600 years from AD 1368 to AD 1950,occurred once every six years. There existed 45 mild flood disasters which accounted for 44. 1% of the total amount of flood disasters,37 moderate flood disasters made up 36. 2% and 4 catastrophic flood disasters consisted in 4. 1%. It was found that the frequent change of climatic characteristics, the features of geomorphology in the fiver basin and the change of river channel during the ＂Little Ice Age in Ming and Qing Dynasties＂ were the main factors to cause flood disasters.