The Basic Study Of Floods And Droughts In Tuo River Basin During The Ming And Qing Dynasty

Tuo river is an important tributary of the upper reaches of the Yangtze River north bank, which is running through the northern Sichuan mountain, Chengdu Plain, the Sichuan middle basin and hills and the other terrain units. The topography of this basin is sophisticated which makes the basic place of floods and droughts occurred in Tuo river basin. This situation makes the trait of the floods and droughts of Tuo river to be diversified, sophisticated and regionalized. The research of the floods and droughts occurred in Tuo river has an important reference value and significance for our understanding of the characteristics in time and space and the way of floods and droughts happened in Yangtze River.In order to analyze the basic situation of the floods and droughts in Tuo river basin during Ming and Qing dynasty, I am trying to analyze and do research in the following steps:The first, in order to acquire the basic statistics sample, I’ve thumbed the local chronicles of Tuo river basin, archival materials, a record of the Ming Dynasty’s events, a record of the Qing Dynasty’s events, data in newspapersand periodicals, statistical data of neoteric researchers and survey data. I referred the following books: Chinese ancient chronology of major natural disasters and abnormal collections, Chinese meteorological records of three thousand years collections, Chinese historical flood survey data compilation, Chinese meteorological disasters records(Sichuan), southwest international rivers historical archives of the Qing dynasty Yangtze river basin floods, Sichuan flood historical compilation of two thousand years, Sichuan ancient natural disasters brief, the floods and droughts compilations of Sichuan before the Qing dynasty, Sichuan water conservancy compilations of the late Qing and the early republic, A preliminary study of the historical records of climate in Sichuan, Severe floods and droughts in Sichuan century historical(1962).Then sorting out the annual sequence of floods and droughts occurred in Tuo river during the Ming and Qing dynasty. For the quantitative analysis of the statistics, I try to through the number of the county with disaster, the area of the place with disaster and the number of the population with disaster to make the annual index table of the Tuo river basin’s floods and droughts during the Ming and Qing dynasty. the quantity of disaster reflect the frequency of certain disaster, and the index of disaster can count the extent of the disaster of the county. These content makes the chapter one what is “the source and quantization of data and the analysis of disaster index.Chapter two is “the distribution of floods and droughts in Tuo river during the Ming and Qing dynasty”. I analyze the basic trait in time and space of the distribution of floods and droughts in Tuo river during the Ming and Qing dynasty. In the time aspect, I analyze the dynastic traits, annual traits and seasonal traits. In the space aspect, I analyze the county traits, secondary basin traits and the basin traits. With the analysis of the trait of distribution, I can have a preliminary understanding of the basic law of the floods and droughts in the Tuo river during the Ming and the Qing dynasty which can be the foundation of disaster prevention and disaster relief in the basin.Chapter three is to analyze the reason of the occurrence floods and droughts in Tuo river basin during the Ming and Qing dynasty. The occurrence of floods and droughts is the comprehensive action of natural environment and humanities and social environment that makes the dual properties of disaster, which is natural properties and social properties. I want to analyze the reason of the occurrence floods and droughts in Tuo river basin during the Ming and Qing dynasty from the these two aspects. The natural geographic features like topography, vegetation, hydrological environment, climatic fluctuations and its change is the mechanism of ecological environment of floods and droughts which is called disaster-pregnant environment. From the aspect of the subject of disaster, the occurrence of disaster is a circulation process of the disaster-pregnant environment, disaster-inducing factors and element at risk. And the element at risk is the human society. The abilities of its bearing the disaster-inducing factors have an important influence of the extent of the disaster. So I try to have an understanding of the ability of social bearing in Tuo river basin from the agricultural industry, warehouse construction, disaster relief, the ritual of pray god asserting disaster.