摘要
利用浑浊理论，计算长江流域和黄河流域中下游地区近５００年旱涝时间序列资料表明，旱涝系统是一种浑沌系统，其吸引子维数约为３．３～４．５，确定性的可预报时间尺度约为１１～１６年。
The time series data of recent 500 years in the middle and lower reaches of Huanghe andChangjiang river valleys are calculated in the chacol theory. This shows that the drought and waterlogging system is a chaotic one with the attractor dimension 3．3～4． 5 and the definite time scale ofpredictability 11～16 years.
关键词
旱涝
分维结构
可预报性
河流域
中下游地区
：Drought and water logging system；Fractal dimension structure；Predictability.
