Preliminary Study On The Flooding And Drought During The MIing And Qing Dynasties Of China In Mingjiang Drainage Basin

The historical period flood and drought research is not only an important aspect of the history of disasters,but also the main content of historical geography.This article to collect data from the Minjiang river basin of Ming and qing dynasties local Chronicles, archives, the survey data, the compilation of historical materials, drought and flood inundation and so on. On the basis of using the research methods of historical geography, to quantify the flood and drought during the Ming and qing dynasties of Minjiang river basin is statistical analysis.The preliminary conclusion is about the level of flood and drought during the Ming and qing dynasties in Mnjiang river basin and the characteristics of time and space distribution.Then to analyze the reasons of flood and drought disaster and their effects.Studies show that during the Ming and qing dynasties,the flood and drought was a trend of increase gradually, the characteristics of time and space distribution is not equilibrium, and the flood is more serious than drought. the flood and drought disasters is mainly mild and moderate.On the time distribution of flood and drought disaster, the Qing dynasty is more than the Ming dynasty, which is suitable for a peak period of flood and drought disaster in the18th and19th centuries, particularly in the19th century.Flood occurs mainly in summer and fall, mainly in June; Drought occurred in the summer, then in the spring and fall,less in winter.On the spatial distribution,the middle and lower of Minjiang river.Qingyijiang river and the downstream of Dadu river is the flood epicenter.As a representative of Dujiangyan,Chongzhou,Leshan,Qianwei,Yingjing,Hanyuan.the drought in the middle and lower reaches of Minjiang river is frequently.then the Qingyijiang river,the last is Dadu river.Rengshou,Leshan,Qianwei,Jinyan is the severely afflicted area of drought.